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CHNG 1 - H THNG QUN L KHAI THC NG T

1.1 - H thng mng li ng t - cc vn qun l

Chc nng, nhim v qun l khai thc mng li ng b

Qun l ng b xut pht t lp lun cho rng mng li ng b l mt ti sn cn c bo dng v ci to nhm t c kh nng phc v tt nht, gi gn c gi tr ti sn mc cao nht c th v tui th phc v ti a c th. Mc ch qun l ng l gip mng li c th chng li s pht sinh cc h hng , gim tc xung cp ca ng v m bo giao thng thng sut, an ton, hiu qu, tin cy v t gy nguy hi cho mi trng nht. Cc mc ch ny t c thng qua mt chui cc cng vic v hot ng, m do tnh hiu qu qun l ca n, ph thuc vo vic duy tr cc thng tin cp nht v c im v tnh trng ca mng li ng.

Cc hot ng qun l bo dng mng li ng b

Cc cng vic v cc hot ng c trin khai trong qu trnh qun l ng b thng c phn loi theo tn xut thc hin v c im ca ngun vn, th hin trong bng 1.1

Bng 1.1 - Cc loi cng vic qun l bo dng ng b

Tnh cht Mc

thng xuyn Ngun ngn sch V d

Thng xuyn Trong khong thi gian di 12 thng

Thng theo nh k - Bo dng theo chu k

- Bo dng sa cha

nh k Vi nm mt ln Theo nh k hoc ngn sch vn

- Bo dng d phng

- Lm li b mt

- Lp ph

- Thi cng li mt ng

c bit Khng th d on chc chn

Bo dng t xut trong ma ma, c th l nh k

- Cc cng trnh khn cp

- Bo dng ma ma l

Pht trin c lp k hoch ti cc thi im khc nhau

Thng l ngn sch vn

- M rng

- Ci to

- Xy dng mi

Cc chc nng qun l ca h thng qun l mng li ng b

H thng qun l ng b c thit lp tha mn cc chc nng nh sau:

Lp k hoch

Lp chng trnh

Chun b

Vn hnh

Bng 1.2 - Cc chc nng qun l

Chc nng Mc ch qun l Mc Thi hn Cp qun l

Lp k hoch

- Xc nh cc ngng, cc tiu chun thc hin qun l

- Xc nh ngun ngn sch

Ton b mng li Di hn (chin lc)

Cc nh hoch nh chnh sch

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Chc nng Mc ch qun l Mc Thi hn Cp qun l

Lp chng trnh

Xc nh chng trnh lm vic c th c thc hin trong phm vi k ngn sch

Cc hng mc c th cn c x l

Trung hn (chin thut)

Cc Ban qun l, cc Gim c D n

Chun b Thit k cc cng trnh

Chun b hp ng v ch dn thc hin

Hp ng hoc cc gi cng vic

Nm ngn sch

K s, k thut vin v cn b qun l hp ng

Thc hin Thc hin cc nhim v theo chng trnh

Cc n v c cc cng trnh ang c trin khai

Lin tc Cc k s gim st, cn b qun l hp ng

Qun l ng c th c xem l mt qu trnh lng ghp gm cc chu trnh hot ng tham gia vo tng chc nng qun l nh lp k hoch, lp chng trnh, chun b v vn hnh. Mc d mc tiu ca cc chc nng ny khc nhau nhng cc chc nng ny u hng n thng tin v mng li ng b. Ni cch khc, cn lin tc c cc thng tin phn hi v cc d liu trong phm vi chu trnh qun l v gia cc chu trnh lin tip.

Chu trnh qun l mng li ng

Qun l ng b cng nh bt k hot ng qun l no u bao gm cc nhim v nh sau:

- Xc nh cc hot ng

- Ln k hoch

- Phn b cc ngun lc

- T chc v huy ng nhn lc

- Kim sot cng vic

- iu khin v nh gi mc hon thnh

- Thu thp cc phn hi tm gii php ci thin

Tt c cc hot ng qun l bo dng ng b c th c thc hin theo cc bc nh sau v c th c hiu l chu trnh qun l mng li ng

Hnh 1.1 - Chu trnh qun l mng li ng

Xc nh mc tiu

nh gi nhu cu

Xc nh cc hot ng

Thc hin cc hot ng

Kim sot v kim ton

QUN L THNG TIN

(CC D LIU)

Xc nh cc chi ph v cc u tin

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Xc nh mc tiu

Chnh sch chung v th ch trong Qun l ng b c nh hng quan trng n cng tc qun l ng. Chnh sch s xc nh mc tiu ca qun l ng. Xc nh mc tiu l bc u tin cn thit trong chu trnh qun l ng xc nh mi chc nng quan l m t cc hot ng s c tin hnh t c mc tiu.

nh gi nhu cu

Bc c bn trong phn tch nh gi nhu cu l cng tc thu thp s liu. Cc thng tin thu thp c s gip xc nh cc hot ng cn phi tin hnh.

Xc nh cc hot ng

C th c nhiu gii php cho tha mn cc nhu cu xc nh c t c cc mc tiu t ra. Vn l cn phi xc nh cc hot ng ph hp c th tha mn c mc tiu qun l c t ra.

Xc nh cc chi ph v cc u tin

Cc hot ng xc nh c s yu cu cc chi ph tng ng. Thng thng cc chi ph c yu cu s ln hn ngun lc (ngun vn) c c. Vic xc lp cc u tin trong trng hp ny s gip cng tc phn b ngun vn mt cch hp l v c hiu qu v mt kinh t.

Thc hin cc hot ng

Bc ny bao gm ton b cc hot ng cn thc hin i vi chc nng qun l. Vic thc hin cn phi m bo rng cc hot ng c tin hnh theo ng cc tiu chun m bo thc hin c cc mc tiu qun l. Cng tc gim st c xem l quan trng trong bc thc hin ny

Kim sot v kim ton

Kim sot l chc nng thc hin cung cp cc phn hi cho quan trnh qun l thc hin tip tc cho mt chu trnh qun l sau. V d nh cc mc tiu c th c xc nh li cn c vo iu kin thc t, cc n gi c th sa i cn c vo iu kin thc ca hin trng hay cc gii php k thut c th c ci thin trn c s vic kim sot thc hin.

Kim ton bao gm kim ton k thut v kim ton ti chnh l thc hin cc cng vic kim tra xc nh li cc tiu chun hay cc qui trnh cn tin hnh.

Cc hot ng trn c gi l mt chu trnh, v n l mt qu trnh lp li. Cng tng t nh vy i vi chc nng qun l h thng mng li ng, cng c th xem nh l mt chu trnh c thc hin t : Xc lp mng li Lp k hoch thc hin, mi bc ny li l mt chu trnh qun l mng li ng (nh th hin trong hnh sau)

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Hnh 1.2 - Qu trnh lp ca chu trnh qun l mng li ng

Cc bc thc hin trong chu trnh qun l mng li ng b v cc chc nng qun l tng ng c lit k trong bng s 1.3 sau:

Bng 1.3 - Chu trnh qun l mng li ng b v cc chc nng qun l trong mi bc ca chu trnh

Cc bc trong chu

trnh qun l

Cc chc nng qun l

Lp chng trnh chin lc

Ln k hoch thc hin

Chun b Thc hin

Xc nh cc mc tiu

- Xc nh cc gii php chung nhm gim thiu tng chi ph (chi ph ton b vng i) cho c mng li.

- Xc nh tng chi ph yu cu thc hin cc gii php ra.

- Lp k hoch thc hin cc cng vic trong chng trnh hoc s dng ngun vn phn b cho nm ti

- Thc hin thit k

- Chun b cc ti liu hp ng v lp ch dn thi cng

Thc hin cc hot ng thi cng

nh gi nhu cu

- nh gi nhu cu c s dng cc kt qu kho st v tnh

- nh gi nhu cu bng cch so snh cc o c tnh

- nh gi qua tin hnh cc kho st chi tit v iu

Cc nh gi c thc hin :

LP K HOCH

THC HIN

LN CHNG TRNH - CHIN LC

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Cc bc trong chu

trnh qun l

Cc chc nng qun l

Lp chng trnh chin lc

Ln k hoch thc hin

Chun b Thc hin

trng mng li ng cho cc cng vic bo dng nh k, cc d liu lu tr cho cc cng vic mang tnh cht chu k hng nm v cc cng vic c bit (bo dng t xut)

trng mng li vi cc tiu chun ca bo dng nh k v ca mt s hot ng bo dng p ng v cc s liu lu tr cho cng vic mang tnh cht bo dng t xut

kin ca mng li ng thc hin cc thit k theo cc tiu chun.

- Chun b cc mu hp ng ph hp.

- kim tra chi tit cho cc cng vic mang tnh cht p ng v cc cng vic bo dng nh k

- lp tiu chun cho cc cng

vic mang tnh cht chu k

Xc nh cc hot ng

- Xc nh cc gii php sa cha theo tiu chun tnh ton nhu cu v ngn sch

Cc la chn cng vic duy tr tnh trng ng theo cc tiu chun c yu cu

- Thit k cc gii php sa cha, la chn gii php sa cha theo cc tiu chun c p dng cho d n

- La chn cc tiu chun, cc ch dn k thut thc hin ph hp vi mi hot ng

Xc nh chi ph v cc u tin

- p dng cc n gi a ra yu cu v ngn sch vi cc cng tc sa cha c u tin tha mn c cc hn ch v n gi

- p dng cc n gi xc nh yu cu v ngn sch trong trng hp khng xt n u tin

p dng cc n gi v cc phng n c u tin xy dng mt k hoch bo dng sa cha trong phm vi ngn sch

Cc n gi chi ph c p dng v cc u tin c khng nh li

- Chun b biu khi lng

p dng cc mc tiu, cc yu cu v ngun nhn lc, thit b v vt liu theo tiu chun

Thc hin cc hot ng

- Ban hnh cc tiu chun

- Ban hnh cc nhu cu ngn sch d kin

Trnh np k hoch thc hin cng tc bo dng sa cha

Thc hin cc thit k, cc bn v,..

Chun b cc hp ng v ban hnh cc ch dn thi cng

Thc hin cng tc gim st

Kim sot v kim ton

- Xem xt cc d kin trc khi tin hnh chu k k hoch tip theo

- Xem xt trnh t lp k hoch

Xem xt chng trnh trc khi bt u chu k sp ti

Xem xt cc trnh

t lp k hoch

R sot hay kim tra thit k, r sot hp ng hay ch dn thi cng

R sot qui trnh

thit k

R sot cc kt qu t c so vi mc tiu ra

R sot qui trnh

cho hot ng qun l thi cng

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Cc bc trong chu

trnh qun l

Cc chc nng qun l

Lp chng trnh chin lc

Ln k hoch thc hin

Chun b Thc hin

Thi gian ca chu k hot ng

- Thng thng 3 - 5 nm

Thng thng 1 nm

t hn mt nm Mt s ngy hoc mt s tun

Cht lng qun l khai thc ng

Mc tiu cao nht ca qun l khai thc mng li ng l m bo tha mn yu cu ca ngi s dng ng. Nh vy, cc yu cu ca ngi s dng ng phi c a vo cc chnh sch th ch v cc mc ch hot ng ca cc c quan qun l dng v c th ha cc yu cu ny trong cc k hoch thc hin cc hot ng qun l khai thc ng. Mt h thng qun l mng li ng m bo cht lng bao gm cc vn sau y:

- Xc nh trch nhim qun l: trch nhim qun l ca cc cp/ cc phng ban/ c nhn trong h thng qun l khai thc ng cn c xc nh r.

- Qui trnh qun l (cho mi mt hot ng bao gm trong qun l khai thc v bo dng mng li ng) cn phi c chun ha qua cc ti liu mang tnh php l v c qui trnh kim tra, kim ton.

- Cc hot ng khai thc, bo dng phi c kim tra, gim st v ph duyt theo mt qui trnh chnh thc mang tnh php l.

- C qui trnh chun, bt buc lu ghi cc hot ng bo dng c tin hnh

- Thc hin cc hot ng kim tra, sa i thng xuyn i vi cc hot ng qun l khai thc ng.

1.2 - H thng mng li ng t - cc vn v th ch

Phng thc thc hin qun l ng b v cc hn ch ca mi phng thc chu nh hng ca nhiu yu t, c chia theo nhm ni yu t v ngoi yu t tng ng vi . Cc ni yu t l nhng vn nm trong ni b h thng qun l khai thc ng, bao gm cc vn k thut v cc vn v th ch.

Cc vn v k thut phn nh nng lc ca n v qun l thc hin cc nhim v qun l v bo dng, c th xem nh l phn cng ca ni yu t:

(1) Kh nng c c v s dng c cc:

- s liu

- cc vt liu v cc ngun cung cp vt liu

- my mc v thit b thc hin cc hot ng qun l v bo dng

(2) Kh nng thc hin c:

- khai thc k thut mng li ng

- kim sot cc hot ng v cc phn hi t cc hot ng khai thc ng

(3) Kh nng tip cn c cc nghin cu v cc ngun thng tin lin quan n khai thc ng b.

Cc vn v th ch lin quan n h thng t chc qun l, ngun vn, ngun nhn lc,... y c th xem nh phn mm ca ni yu t, bao gm

(1) Qun l ti chnh v cc ngun vn, bao gm c li nhun, ngun ngn sch v cc chi ph

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(2) H thng t chc v qun l, bao gm vic thc hin chnh sch, c cu t chc qun l hnh chnh, lp k hoch, ln chng trnh thc hin, cng tc chun b cho cc d n bo tr, duy tu ng v qun l thc hin cc d n.

(3) Ngun nhn lc bao gm c cu thnh phn v qui m ca ngun nhn cng, pht trin ngh v o to trong cc c quan qun l khai thc ng.

Cc ngoi yu t l cc vn m bn thn cc c quan qun l khai thc ng khng th kim sot c, nhng c th gy tr ngi cho vic thc hin khai thc v qun l khai thc ng. Cc ngoi yu t bao gm:

(1) Cc yu t mi trng ng b (mi trng t nhin v hu ht cc yu t mi trng x hi)

(2) Khung chnh sch th ch

(3) Nn tng vn ha - x hi ca quc gia

(4) Tnh hnh chnh tr quc gia

(5) Cc vn v kinh t v m v ngun lc quc gia

(6) Chnh sch v nhn cng chung ca chnh ph

(7) Cc mi quan h vi cc c quan chnh ph.

Khung chnh sch trong qun l khai thc ng

Trong phn trnh by v chu trnh qun l, bc u tin ca chu trnh l xc nh chnh sch v mc tiu. iu c ngha l khung chnh sch to lp c s a ra cc quyt nh lin quan n qun l khai thc ng b. Cn phn bit khung chnh sch vi k hoch chin lc. Khung chnh sch gii quyt vn lm ci g v ti sao , cn k hoch chin lc l lm th no; ai lm; khi no lm v lm u. Chnh sch c th c hiu l bao gm:

(1) Cc iu lut v cc qui nh lin quan, c bit l cc vn bn v cc thng bo

(2) Cc quyt nh v cc vn quan trng

(3) Cc hng dn chnh sch v cc qui trnh c ban hnh lin quan n cc c quan qun l ng b.

Mt khung chnh sch c th ha cc qui nh v cc yu cu c bn trong cc quyt nh v k thut lin quan n mng li ng b. Nu khung chnh sch c xc nh tt, s c cc hng dn c th xc nh cc vn nh l phn b ngn sch, u tin v cc chc nng ca cc cp qun l hnh chnh mng li ng b. Vai tr v k thut v chuyn mn ca cc cp qun l l xut cc gii php k thut ph hp thc hin chnh sch. Chnh ph cn kim tra xem chnh sch c thc hin nh th no v nhn cc phn hi t cc cp qun l xem xt ci tin hoc sa i cc chnh sch trong tng lai.

Mt khung chnh sch thng thng c thit lp theo ba mc :

Tng th

Cc mc tiu

Cc tiu chun

Khung chnh sch mc tng th c thit lp bi cc chnh tr gia v cc nh hoch nh chnh sch. Chnh sch c thit lp c mi lin quan mt thit vi chc nng lp k hoch - chin lc trong qun l mng li ng. Mt khung chnh sch, mc tng th ni chung c th bao gm:

(1) Cung cp mc phc v chp nhn c cho ngi s dng ng, m bo an ton v kinh t

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(2) Gim thiu chi ph cho ngi s dng ng v chi ph qun l ng trong phm vi c th c ca ngun ngn sch

(3) Thc hin cc hot ng qun l khai thc mt cch y , hiu qu v an ton, m bo gim thiu cc nh hng ca cc hot ng n mi trng

Ty thuc mc pht trin kinh t ca mi quc gia, mc ch pht trin trong tng giai on, khung chnh sch tng th v qun l khai thc ng c th khc nhau. V d v mc tng th ca khung chnh sch trong qun l khai thc mng li ng b ti Anh, ban hnh nm 1996:

(1) Khuyn khch mt th trng qun l khai thc hiu qu phn nh chi ph thc trong giao thng.

(2) Cung cp nhiu c hi hn cho lnh vc t nhn

(3) Cung cp c hi ln hn cho ngi s dng la chn cc dch v vn ti c cht lng tt, an ton v c kh nng tip cn cao v thc y tng trng kinh t.

(4) Khuyn khch pht trin cc hnh thc vn ti c ng, an ton v m bo an ninh

(5) Gim thiu cc nh hng ca giao thng n mi trng

(6) Khuyn khch chnh sch pht trin giao thng lin vn quc t

(7) Khuyn khch s dng y , hiu qu cc ngun lc v nng cao trch nhim ca cc c quan qun l ng b

(8) Thc hin cc dch v cp php, ban hnh iu l v thanh ton mt cch hiu qu v kinh t, duy tr cht lng phc v cao cho sn xut v cho cng ng ni chung

hay mt v d khc v khung chnh sch mc tng th ti n :

(1) m bo giao thng thun tin, an ton v ph hp chung cho cng ng

(2) m bo cc u t vo ng, cu v cc thit b trn ng c bo tr

(3) m bo duy tr tnh thm m v s ph hp ca cc cng trnh giao thng n mi trng

(4) Cc chi ph cn thit v cc ngun lc cho mng li ng ph hp vi cc im nhn ca chnh sch pht trin kinh t mang tnh cht lin tc.

thc hin khung chnh sch tng th, cc mc tiu v cc tiu chun, cc nh mc thc hin cho mi mc ca khung chnh sch tng th cn c xy dng m bo cc hot ng qun l khai thc mng li ng c thc hin theo ng khung chnh sch.

Cc mc tiu v vy cn c thit lp m bo cc yu cu:

C th lng ha (o, m) c: cc mc tiu c lng ha c th xc nh xem c t c hay khng v xc nh khung thi gian t c

Mang tnh lin quan: cc mc tiu m bo ph hp v c th p dng i vi cc nhim v qun l v chu nh hng trc tiu cu cc hot ng nm trong cc nhim v ca cc c quan qun l khai thc ng

Mang tnh c th: cc mc tiu m bo r rng, c th v ring bit trnh gy ra s hiu nhm.

Cc mc tiu m bo c th t c: cc mc tiu mang tnh thc t, m bo cc c qun l ng c th thc hin c trong mt khong thi gian ph hp vi ngun kinh ph c c.

Cc tiu chun v cc ngng can thip c thit lp a ra cc tham s xc nh xem cc mc c t c hay khng trong mi tnh hung c th. Cc tiu chun v cc ngng can thip trong qun l khai thc ng c th khc nhau ty thuc mi quc gia, thm ch c th khc nhau i

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vi mi n v qun l ng khc nhau. V d, mt n v qun l ng c th a ra tiu chun v ngng can thip m bo cc mc tiu trong khung chnh sch chung c th t c, nhng c n v ch t ra tiu chun v ngng can thip m bo mc phc v ti thiu cho ngi s ng ng. Ngoi ra, cc mc tiu, cc tiu chun v cc ngng can thip c th khc nhau ph thuc vo chc nng ca ng v phc thuc vo mc giao thng trn ng, chng cng c th khc nhau theo iu kin c th v a hnh.

Tm li, khung chnh sch thit lp c ch cho vic a ra cc quyt nh ca cc cp qun l ng. Cc mc tiu, cc tiu chun v cc ngng can thip bao hm trong khung chnh sch l c s cho vic thc hin tt c cc hot ng qun l khai thc ng.

Ch s thc hin

Ch s thc hin qun l khai thc ng b cn c xc nh r mi cp qun l. Cc ch s ny cn phi phn nh c khung chnh sch, phc v cho cc mc tiu hot ng ca cng tc qun l khai thc.

Cc ch s nh gi thc hin c thit lp phc v cc mc tiu sau y:

- Lm cng c a ra cc quyt nh qun l

Cc ch s nh gi thc hin cung cp cc thng s u vo phc v cc cp a ra cc quyt nh v qun l nh l cc mc u t, cc chi ph bo dng v tn sut thc hin cc chi ph qun l, cc quyt nh khai thc mng li hng ny nh l qun l giao thng.

- Lm cng c d bo

Cc ch s nh gi thc hin cung cp kh nng xy dng cc h thng cnh bo sm xc nh v tr thch hp cho thc hin cc hot ng bo dng phng nga phng cc hu qu xu v hn ch tc xung cp ca mt ng.

- Lm cng c thc hin v kim sot

Cc ch s nh gi thc hin c dng nh gi mc v thch hp ca cc chnh sch qun l nh nc v qun l hnh chnh bng vic a ra c ch v phng php nh gi i vi thnh cng ca cc chnh sch v cc mc tiu xc nh trc.

- L h thng kim tra v cnh bo

Cc ch s nh gi thc hin cung cp thng tin cho ngi s dng ng, bao gm cng ng kim sot hiu qu i vi cng ng ca h thng mng li ng.

- Phn b cc ngun lc

Cc ch s nh gi thc hin h tr vic phn chia v kim sot hiu qu cc ngun lc bng cch nh lng hiu qu u t tng i ca cc gii php thc hin. V d c th dng tng quan cc ch s thc hin so snh vi t l chi ph u t gia cc khu vc hay ca cc a phng

- H tr hon thin cc h thng thng tin

Cc ch s nh gi thc hin c th cp nht trong cc h thng thng tin trong mi tng quan vi cc s liu v chi ph xy dng v cc chi ph khc trong xy dng v qun l c s h tng.

Ngn hng Th gii (WB) gi cc ch s thc hin nn c thit lp trn c s cc danh mc ch yu c lit k trong bng 1.4

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Bng 1.1 - Gi ca WB v cc ch s thc hin trong qun l khai thc mng li ng

Nhm Hng mc

Cung cp c s h tng

Qui m mng li

Gi tr ti sn

Tng s ngi s dng ng

Nhn khu hc v kinh t v m

Kh nng sn c

Mc s dng

Cht lng dch v

Mc thun tin cho ngi s dng ng nh gi

Him ha mt an ton cho ngi s dng ng

Tnh c ng

Tnh c th tip cn

Chi ph ca ngi s dng ng

Hiu qu thc hin

Tin gii ngn

Tin thc hin

Hiu qu thc hin

Hiu qu cc b (khu vc)

Chc nng ng

Hiu qu bo tr

An ton giao thng

H thng t chc

Khung chnh sch cng l c s cho c cu t chc qun l khai thc ng, ph hp vi cc yu cu ca khch hng l nhng ngi s dng ng. Mt t chc qun l mng li ng b cn c b tr bao qut cc lnh vc cng vic sau:

Xy dng chnh sch

Ch o chung v mt ng li v qun l t chc, thng thng l vai tr ca cp lnh o/ ban gim c.

Qun l ng b

- Ln k hoch, lp chng trnh lm vic, chun b v thc hin bo dng thng xuyn, bo dng nh k v cc hot ng pht trin mng li ng.

- Thc hin bo dng khn cp: bo dng ma ma l v sau tai nn

- Qun l hnh chnh,

Pht trin t chc

- Nghin cu v pht trin

- o to.

1.3 - H thng thng tin trong qun l mng li ng

1.3.1- Nhu cu thng tin

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Trong chu trnh qun l mng li ng b, qun l thng tin c t chnh gia chu trnh qun l. Tt c cc quyt nh qun l da vo u l cc thng tin ph hp v cp nht nhm h tr cc quyt nh ny. thc hin cc hot ng qun l mng li ng, cn thng tin v cc hng mc nh chi tit mng li, trng ti trc xe v lu lng giao thng, chi ph v tnh trng ca cc tuyn ng v.v. ngc li, cc hot ng ny chnh l cc d liu tng ng lm c s cho ngun thng tin. Nhu cu thu thp, lu tr v phn tch cc c tnh hnh hc, cc c trng mt ng, c im an ton, mc phc v v hiu qu vn hnh ca mng li ng c l cn thit khng ch cho cng tc qun l khai thc ng, m cn rng ri trong cng ng nhng ngi s dng ng. Bn cnh yu cu nhn bit cc c tnh vn c ca h thng mng li ng, kh nng d on qui lut pht trin v cc nh hng n kh nng xut cc chnh sch trong tng lai li cng c ngha quan trng hn. Kh nng d on gip cc nh hoch nh chnh sch th nghim cc phng hng hnh ng nhm quyt nh chnh sch v chin lc no s em li nhiu hiu qu nht nhm t c cc mc tiu mong mun trong phm vi cc ngun lc sn c.

Cc d liu cn phi cung cp c s cho cc quyt nh qun l trong cc lnh vc sau:

Quyt nh tnh trng ng ti u, cc chin lc qun l v cc chi ph cn t c iu kin ny

Quyt nh tnh trng ng ti u trong phm vi ngun ngn sch hn hp thc t

nh gi trnh trng ng v cu trong iu kin khai thc hin ti

Quyt nh mc u t ph hp

u tin ci thin vn v u t vo cng tc bo dng

D bo nh hng ca cc hot ng trong bo dng, nng cp n tnh trng mng li ng trong iu kin tng lai v kh nng phc v ca cc tuyn ng

D ton cho cc hot ng bo dng, nng cp ng

Kim sot chi ph ca cc hot ng c thc hin

Thng tin qun l loi ny cung cp c s nh lng ca cuc i thoi gia b phn qun l k thut v qun l ti chnh trong vic phn b ngun vn, ng thi cng c th cung cp c s i thoi gia i din ca ngi s dng ng v c qun qun l khai thc ng khi qu trnh qun l mng li ng ng c hot ng vi s theo di kim sot cng khai ca cng ng. Cc thng tin qun l v h thng lu tr thng tin cn phi d hiu cc nhn vin trong cc c quan qun l ng d dng tip cn v s dng. S lng ngi s dng thng tin ln t ra yu cu thng tin phi c trnh by di cc hnh thc ph hp vi cc yu cu khc nhau ca ngi s dng.

Cc nhm thng tin

Cc nhm thng tin trong h thng qun l bo dng ng bao gm:

ng k ng

Giao thng

Mt ng

Ti chnh

Cc hot ng

Cc ngun lc

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Bng 1.2 - Cc nhm thng tin trong qun l ng

Cc nhm thng tin Cc thng tin c xem xt

ng k ng Mng li/v tr trn mng li

Yu t hnh hc

Trang b/thit b h tr

iu kin mi trng xung quanh

Giao thng Lu lng

Ti trng

Cc v tai nn

Mt ng Kt cu mt ng

Tnh trng mt ng

Cc kt cu cng trnh ng k loi, v tr ca cng trnh

Tnh trng kt cu

Ti chnh Cc khon chi ph

Ngn sch

Li ch

Cc hot ng Cc d n

Cc gii php bo dng d phng/ sa cha

Cc hp ng

Cc ngun lc Nhn lc

Vt liu

Thit b

1.3.2 - Li ch ca vic vn hnh h thng thng tin qun l mng li ng b

Vic thit lp v vn hnh h thng thng tin qun l mng li ng b mang li nhiu li ch khng ch i vi ngi lm cng tc qun l, m cn c li i vi hiu qu qun l.

Qun l kinh t tt hn

- Khi s dng h thng thng tin qun l ng ng b, cc quyt nh u tin da trn c s li ch kinh t; cc bin php bo dng sa cha c la chn trn c s em li li nhun u t cao nht trong khun kh ngn sch hn ch. Vic s dng h thng qun l nh vy s em li hiu qu u t cao hn xt v kinh t.

- Cc u tin da vo d on xung cp ca tnh trng mt ng; cc bin php x l c la chn theo thi im cc bin php ny c p dng trn c s d on xung cp v tnh trng tuyn ng ch khng phi da vo tnh trng hin ti. Cc gii php v vy s ng v hiu qu hn.

C th a v cc khuyn ngh c ch hn

- sn c ca thng tin v cc xu hng xung cp ca ng trong tng lai v xu hng xung cp ca ng theo lch s pht trin nhm h tr vic to lp cc yu cu ngn sch v chnh sch u t.

H tr thit k tt hn

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- H thng thng tin v ng lu tr cc thng tin tnh trng mt ng bao gm cc h hng c phn chia: theo h hng b mt, h hng kt cu, hay h hng khe ni (i vi ng b tng),... s c th h tr vic la chn bin php x l thch hp v ng n

- C sn h thng d liu a vo thit k

- Cho kh nng xem xt cc cch kt hp d liu chuyn ho my tnh vi d liu hnh nh (trong mt s phn mm qun l ng cao cp)

H tr cng tc gim st

- Mt h thng thng tin qun l mng li ng c th h tr kim sot hiu qu ca cng tc gim st do lun lu tr c cc h hng ban u, cc thng tin thit k, cc quyt nh thit k v h s cng vic. Vic so snh i chng cn c th cho php nh gi hiu qu ca cc hot ng bo dng sa cha v ca cc k hoch bo dng sa cha.

Ci thin hiu qu chung cho qun l mng li ng

- Mt h thng thng tin hon chnh v ton din s c th c s dng trong mi giai on ca qu trnh qun l ng t quyt nh gii php n qun l thc hin. Vi mt h thng nh vy, vic qun l khng ch n gin, khng i hi h thng nhn s cng knh, tn km v cn gip chun ha cc bc thc hin m bo hiu qu ca cc hot ng.

- Kh nng phn cp ca chng trnh p ng nhu cu ca cc cp qun l khc nhau. Vi kh nng phn cp ca h thng t giai on vo, cp nht s liu s khuyn khch p dng kho st cp mng li v cp d n tn dng c cc ngun lc k thut cc cp khc nhau.

- H thng qun l nu c xy dng mt cch linh hot, c th p dng cho cc loi ng, c ng chnh v ng khu vc cc mc chi tit khc nhau. Vi mt h thng nh vy, c th yu cu thu thp d liu cc mc chi tit khc nhau tu vo tm quan trng ca c tnh ng b c a vo qun l.

- Cc thng tin u ra ca h thng thng tin qun l ng c th c xy dng trnh by theo cc mu d hiu c s dng vn bn v th kt hp vi cc ghi ch linh hot. Cc mu ny c th c lp trn c s biu mu lu tr, bo co h tr ngi qun l trong vic xut cc kt qu bo co nhanh chng, tit kim thi gian qun l.

2.3.3 - Cc i tng s dng h thng qun l ng b

Cc i tng s dung h thng qun l ng b bao gm:

i vi h thng thng tin mng li

- Tt c cc cn b qun l ng b

H thng lp k hoch

- Cn b qun l cao cp

- n v kinh t, n v lp k hoch trong ban qun l

- Cc n v ti tr

H thng lp chng trnh

- Cc chuyn gia trong phng bo tr/qun l ng b

- C quan qun l, phn b ngn sch

H thng chun b

- Phng bo tr/qun l ng b

- Phng thit k

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- Phng u thu/hp ng

H thng vn hnh

- Gim st cc cng trnh

2.3.4 - Cc chi ph chnh thit lp v vn hnh mt h thng qun l mng li ng b

Chi ph xy dng chng trnh

Chi ph xy dng thng thng ch l chi ph cho mt t vn xy dng phn mm qun l. Cc s liu phc v th nghim chng trnh thng thng do cc c quan qun l ng cung cp cn c d liu hin c trn h thng qun l hin ti ca c quan qun l ng

Chi ph vn hnh

Phn cng my tnh

Chi ph mua phn cng mi hoc nng cp thit b c t c tiu chun ging h thng mi bao gm my tnh, my in, thit b lu gi, ng truyn v.v

H thng

Chi ph ng k h thng

Cc ng k phn mm khc

Chi ph ng k cc phn mm mua v hoc chi ph ng k s dng vi h thng bao gm h thng qun l c s d liu, cc giao din h thng v.v.

Thit b thu thp d liu

Chi ph thit b dng km vi h thng nh thit b thu thp d liu (my ghi d liu), thit b o su ca rnh, bo h lao ng dng trong kho st tnh hnh; Chi ph cn phi bao gm chi ph phng tin nu cc phng tin ny ch dng vi h thng.

Thit lp mng li

Tt c cc chi ph thit lp hoc lng ghp mt mng li tham chiu c cho h thng

Cng mng li ti c s d liu

Chi ph nhn s v cc chi ph ng nhp vo mng li, truy cp vo c s d liu

Thu thp s liu thng k v ng Chi ph thu thp cc s liu thng k ng hoc cp nht cc bng thng k ng sn c

Cng t bng kim k ti c s d liu

Chi ph nhn lc v cc chi ph tip cn bng kim k, truy cp vo h thng c s d liu

o to cn b ban u

Chi ph o to cn b nhm to iu kin gii thiu h thng, bao gm c vic o to gim st vin, cn b my tnh, cn b xy dng v.v.

Chi ph vn hnh hng nm

Cn b h tr my tnh

Chi ph dnh cho tt c cc cn b tham gia h tr vn hnh my tnh

Cn b chuyn ngnh

Chi ph dnh cho tt c cc cn b chuyn ngnh bao gm gim st vin, k s, cn b kho st v.v. cho vic thu thp, cp nht v s dng h thng

Bo dng phn cng

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Chi ph bo dng my tnh, thit b b sung bao gm tt c chi ph mua my tnh

Bo dng phn mm

Chi ph bo dng h thng c s d liu cng nh bt c chi ph nng cp v bo dng phn mm cho bn th ba.

Bo dng mng li

Chi ph gi cho mng li tham chiu thng tin cp nht bao gm mi cng d liu v kho st

Bo dng cc bng k trong c s d liu

Chi ph cp nht d liu kim k lin tc, bao gm cc cuc kho st kim k v cng d liu

Bo dng thit b

Chi ph duy tr h thng thu thp d liu bao gm c cc phng tin i li

Lp h s v thuyt trnh

Chi ph thu thp v thuyt trnh h s

Lp chng trnh bo dng hng nm

Chi ph nhn lc

2.3.5 - Yu cu ca h thng thng tin qun l mng li ng

Cc yu cu c bn ca cc nhm thng tin:

- Tnh xc ng

- Tnh ph hp

- tin cy

- Kh nng p ng (cc ng dng v cc i tng s dng h thng)

Tnh xc ng

Mi hng mc d liu c thu thp v lu gi cn phi ph hp vi u ra do h thng yu cu. Cc hng mc d liu khc. c th xem l cc d liu mong mun, ng quan tm hoc c th c ch trong tng lai, cn c tch khi cc cc d liu cn thit, xc ng hoc c th s dng ngay tr khi c mt cch phn tch chi ph-li nhun tt phc v vic thu thp thng tin.

Tnh ph hp

Khi lng d liu v tn sut cp nht thng tin l hai nhn t chnh quyt nh chi ph vn hnh h thng qun l. Mt s loi d liu c cp nht ti cc thi im khc nhau trong mt qu trnh gm nhiu giai on. Yu cu v khi lng v mc chi tit ca cc d liu thu thp cc giai on khc nhau c th khc nhau, thng thng khng ngng b sung cp nht chi tit cho cc thng tin c bn quy nh ban u. V d, nhm phc v cho vic nh gi kt cu mt ng phc v lp k hoch chin lc bo dng ng, d liu tnh trng mt ng cn bao trm ton b mng li vi t l mu i din thp, cn i vi thit k cho mt d n giai on thc hin chng trnh, cn ly mu lng ghp trong phm vi gii hn ca d n thu thp s lng thit k v s lng hp ng.

tin cy

tin cy ca d liu do cc yu t sau quyt nh:

- chnh xc ca d liu, c xc nh bng vic kt hp tnh chnh xc (li lin quan n cc s o kch thc lp li c o c ti cc thi im khc nhau v cc v tr khc nhau).

- Mc bao trm: i vi cng tc lp k hoch cp mng li, cng ly mu thp l ph hp, ngc li i vi vic thit k cng trnh ca d n giai on chun b, cn ly mu tp trung trn ton b khu vc d n.

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- Tnh cht y ca d liu c vai tr rt quan trng v cc hng mc b mt s lm gim tin cy ca kt qu thu c.

- Tnh cp nht m bo cc d liu vn thay i nhanh chng theo tng nm hoc nhng d liu c nh hng ln n quyt nh cui cng c cp nht thng xuyn hn cc d liu thay i chm hn v t nhy cm hn.

Cn cn bng tin cy ca d liu vi chc chn ca kt qu. V d, chnh xc cao, ly mu tp trung ton b mng li, c th t c bng cch s dng thit b hin i, c th coi l u t qu mc nu kt qu thu c ch dng trong khu lp k hoch chung.

Kh nng p ng

S lng v cht lng ca cc hng mc d liu v thu thp d liu lin quan phi c th p ng c v mt ti chnh v ngun lc cn b sn c thu thp d liu v duy tr d liu trng thi cp nht. Phm vi v cht lng ca d liu l hai la chn cn c cn nhc vi cc ngun lc quy nh c th duy tr trong thi gian di v cn cn nhc vi gi tr ca cc quyt nh qun l ph thuc vo hai yu t ny.

Cc n v qun l c cc ngun lc, k nng khc nhau v c th thay i theo thi gian. i vi cc t chc nh hoc va c cc ngun lc v k nng hn ch th cc loi d liu c bn, n gin l ph hp. cc t chc c ngun lc v k nng tt hn c th thu thp phm vi d liu rng ln hn, bao gm c vic s dng cc phng php thu thp t ng ha. Tuy nhin, iu cn thit l cc d liu thu thp v lu tr phi p ng nhu cu qun l cc cp/ cc mc khc nhau.

2.3.6 - ng dng ca h thng qun l v cc m hnh trong h thng qun l

Cc s liu u ra ca h thng thng thng c c t vic kt hp d liu vi m hnh. Vic nh r cc d liu u ra ca h thng s quyt nh cc hng mc s liu s c thu thp v lu gi trong h thng, v loi m hnh c thit lp di dng cc thut ton v cc phng trnh tnh ton cn thit x l cc d liu ny. Do chi ph thu thp d liu thng cao gp 5 n 10 ln chi ph mua phn cng my tnh cho h thng, thit k d liu chnh xc l iu cn thit h thng qun l hiu qu.

Cc d liu u ra ca h thng ph thuc vo ngi s dng h thng, vi mi i tng s dng cc cp qun l khc nhau, c th c cc s liu u ra ca h thng khc nhau. Thng thng, cn phi cung cp u ra t nht hai mc chi tit: tng hp v chi tit. Hu ht cc d liu u ra s c trnh by di dng bng biu hoc c th l th. V d, u ra ca h thng lp k hoch, c dng trong qun l cp cao, thng s d tip nhn hn di dng th, biu . V d nh i vi tnh trng mt ng, c th th hin d liu u ra bng bnh dui thng c k hiu tnh trng mt ng trn cc on khc nhau. Mt s h thng trnh by u ra bng th dng bn m t tt c cc phn ca mng li, vi t l chnh xc theo c hai chiu. Cch th hin ny rt hu ch v th hin ton b mng li chnh xc, tuy nhin, c th c chi ph cao v vic s dng cng yu cu nhiu thao tc phc tp, yu cu my tnh lu tr c dung lng ln, cht lng tt m c th khng ph hp vi iu kin giao thng a phng.

Cc dng m hnh

Cc dng m hnh bao gm cc phng trnh quan h v cc thut ton thng gn vi phn thit k ca h thng. Rt nhiu cc dng m hnh trong mt h thng, t m hnh n gin ch mang ngha thng k phn nh thng thng, n cc m hnh rt phc tp d bo cc bin thay i theo thi gian, m li l h qu ca m hnh khc. Trong h thng qun l ng b, cc m hnh c th thit lp phc v cc mc ch:

- Phn nh cc hng mc ca tuyn ng, vi d liu u ra dng th hin cc thng tin ca tuyn ng, ca mng li ng di dng bn , biu hay cc bng thng tin

- Phn nh tnh trng tuyn ng theo dng ch s da trn cc h hng o c c. S liu u ra i vi mc ch ny cng c th dng bn , bnh dui thng th hin ch s

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h hng ca mt ng trn tng on hay bng thng k ch s h hng ca mt ng theo l trnh/ chiu rng

- D bo tnh trng tuyn ng theo thi gian. y l mt m hnh kh phc tp vi vic d bo pht trin h hng ca tuyn ng da trn cc phng trnh pht trin h hng ca ng ng vi cc iu kin khai thc nht nh: iu kin vng min, iu kin giao thng, tnh trng mt ng hin ti, ch bo dng p dng,...

- La chn bin php bo dng ph hp trn c s tnh trng tuyn ng. La chn bin php bo dng cng l mt m hnh phc tp, c th da trn mt ch tiu cht lng nht nh hay trn c s phi hp cc ch tiu bng ma trn hay bng cc hm s quan h.

- D ton chi ph cho cc hot ng l mt ni dung c thc hin trn c s bin php bo dng la chn. M hnh c s dng l m hnh tnh ton chi ph trn vi vic p dng cc nh mc cho cng tc sa cha v n gi vt liu, nhn cng, my mc,... D liu u ra chnh l chi ph bo dng sa cha ng vi cc hot ng bo dng c la chn tin hnh.

- D on lu lng giao thng: l m hnh da trn quan h pht trin lng giao thng (v d quan h hm s m, hay quan h hm s tuyn tnh vi h s tng trng giao thng hng nm). D liu u ra ty yu cu, thng thng l lu lng xe con quy i

- Phn tch tc ng vi cc d liu u vo l v tr v thi gian ch tc xe trn ng. Chi ph thi gian c th c tnh ton da trn d liu u ra ca phn tch tc ng.

- Phn tch chi ph ca ngi tham gia giao thng, thng thng bao gm chi ph khai thc phng tin v chi ph thi gian i li. y l m hnh rt phc tp do cc chi ph ny ph thuc vo nhiu yu t, trong c yu t bin i, chnh l tnh trng ng

- Chuyn ho u tin cng vic trong iu kin ngun ngn sch hn hp, vi m hnh la chn u tin kh phc tp, phi hp vi ngun ngn sch.

- Phn b ngun vn cho cc khu vc a l, ngn qu, d n,...

V d v d liu u ra ca h thng

Cc d liu u ra ca h thng nh c cp s b trn c phc v cc ng dng trong qun l ng. Ty thuc mc qun l, cp qun l v yu cu c th ca ng dng, c th thit k h thng c c d liu u ra mong mun. Mt h thng c th rt tng hp, bao gm nhiu m hnh, c th s dng p ng tt c cc ng dng ca ngi qun l, hoc c th phm vi hp, mc n gin.

- D liu u ra phn nh cc hng mc ca ng c th hin di dng bn a l bao gm nhn hng mc, chiu di hng mc, im u v im cui theo s tham chiu. Ngoi ra, c th bao gm mt biu thng k m t hng mc.

- D liu u ra ca h thng lp k hoch c th s bao gm:

+ Danh sch cc hng mc trnh by theo th t u tin v bin php x l cng nh d tnh chi ph tng ng c th c ti tr trong nm ngn sch trong iu kin vn c xc nh trc v ngun ngn sch hn ch. Ngi s dng h thng c th lm vic tng tc vi danh sch ny c th sa i cc bin php x l, chi ph v th t cc d n trong danh sch u tin.

+ Danh sch cc hng mc do ngi s dng la chn c trnh by theo th t cc hng mc, tnh trng v cc bin php x l xut.

+ Danh sch cc hng mc do ngi s dng la chn c trnh by theo th t cc hng mc, tng ng vi lu lng v ti trng trc xe v chi ph khai thc phng tin.

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Hnh 1.3 - u ra cho thng k mng li ng

+ Chng trnh cng vic c d on trong giai on 3 nm tng ng vi danh sch cc hng mc c sa cha.

- D liu u ra tng ng vi cng tc chun b cho d n bo tr c th bao gm:

+ Thng tin thit k chi tit (la chn gii php v thit k chi tit)

+ Cc gi cng trnh (theo nh c cn i phn chia)

+ Cc yu cu cng vic ca d n, bn k khi lng

Vit Nam khi ng kh nhiu d n c lin quan n thit lp phn mm qun l mng li ng b, tuy nhin, vic duy tr s dng pht huy hiu qu l km. Cha c mt phn mm chnh thc no c s dng ti Vit Nam, v thit k bo tr hin nay vn cha theo mt qui trnh chnh thc v la chn gii php. Cng tc lp k hoch, chn danh sch tuyn v vy cng cha c thc hin trn c s phn mm qun l v thit k bo tr c thit lp theo cc ch tiu hiu qu kinh t. Ngun vn hn hp cho bo tr v vy cng cha c s dng mt cch c hiu qu.

S chung cho m un h thng thng tin phc v qun l khai thc ng b

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Hnh 1.4 - M hnh thit k h thng d liu thng tin ng b

1.4 - Cng ngh mi trong qun l khai thc ng b

H thng giao thng thng minh ITS

H thng giao thng thng minh (ITS) l ng dng kt ni cng ngh in t, cng ngh my tnh, cng ngh truyn thng v cc thit b pht hin - nh v tin tin, lm tng tnh hiu qu v an ton cho h thng mng li ng. ITS bao gm cc cng ngh :

i. qun l v khai thc tt hn cc tuyn ng hin c, cc tuyn giao thng cng cng v h thng h tng ng st, lm gim mc ch tc v gii quyt cc vn v giao thng.

ii. to iu kin i li an ton v thun tin hn cho hnh khch

iii. chuyn ch hng ha hiu qu hn v m bo an ninh

Nu c s dng mt cch hiu qu, h thng ITS s m ra mt phng php mi cho vic qun l, khai thc, m rng, ci tin v nh hnh ha vic s dng h thng giao thng. ITS chng minh kh nng c th gii quyt c bn qun l khai thc ng cao tc. Kt hp vi cng ngh ITS, h thng qun l ng cao tc (FMS) bao gm h thng in, con ngi, cc thit b v cc chng trnh chin lc c s dng thc hin cc mc tiu ci tin trong khai thc mng li ng cao tc. Mt s cc hp phn ITS ph bin c m t nh sau:

- H thng thit b gim st v pht hin - Cc thit b ny thu thp thng tin v dng xe v v c trng ca ng cho php ngi vn hnh kim sot cc iu kin c th trn ng cao tc. Cc u cm bin in t c th thu thp d liu (lu lng, tc v thi gian xe chy), hay cung cp cc hnh nh qua camera. Cc s liu c thu thp h tr cc chc nng kim sot v ph bin thng tin, cho php ngi vn hnh can thip mt cch thch hp. Cc d liu cn c th c lu gi phc v cc phn tch v nh gi. Cng ngh cm bin cho th

S liu vo

ng k ng

Cc ngun lc bo tr

Cc hot

ng bo tr

Ti chnh

S liu giao

thng

Cng trnh

trn ng

Mt ng

Khung chnh sch

Cc tiu chun v cc ngng

can thip

H thng c s

d liu

X l s liu

S liu u ra

Thng tin

mng li

Lp k hoch

Ln chng trnh

Cng tc

chun b

Vn hnh - khai thc

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cho php h thng kim sot ng v cc iu kin mi trng nh iu kin thi tit v nhit mt ng. Cc thng tin v iu kin ng v mi trng thng c s dng quyt nh cc hot ng cn thit, s dng hiu qu cc ngun lc dnh cho bo dng sa cha ng.

- H thng my tnh v tch hp cc h thng - Cc h thng qun l ng cao tc ph thuc vo h thng my tnh vn hnh. Vic la chn nn phn cng v cc phn mm thch hp phc v cc chc nng nht nh, tch hp cc phn mm v phn cng ph tr thnh mt h thng hon thin, v duy tr h thng hon thin qun l mng li ng cao tc mt cch c hiu qu

- Trung tm qun l giao thng (TMC) - Cc h thng my tnh v cc phn mm ph hp, giao din ngi s dng v ngi vn hnh, giao din gia nhng ngi vn hnh v cc thit b, nhn lc h tr khc thng thng c lp t v vn hnh trong trung tm qun l giao thng, mc d chng cng c th c vn thnh thng qua mng li truyn thng m khng cn mt trung tm chnh thc. Trong mt h thng iu hnh, trung tm qun l thng tin ging nh b no trung tm iu hnh ton b cc hot ng trong khu vc.

- Cc h thng truyn thng - Vic khai thc hiu qu ton b cc chc nng c cp trn cn h thng truyn dn cc s liu, cc tn hiu video v tn hiu truyn thanh. Cc h thng truyn thng truyn cc s liu v cc tn hiu hnh nh, m thanh t hin trng n trung tm qun l giao thng, truyn cc lnh iu khin t trung tm n cc thit b hin trng, truyn s liu gia cc cp qun l, a thng tin n ngi s dng ng v cho php cc c nhn s dng ng c th lin h vi nhau trong mt khong cch nht nh.

Thit b theo di nh gi hin trng mng li ng

- Theo di tnh trng h hng b mt

- c trng cng

- bng phng v nhm mt ng

Cc ch tiu nh gi h hng ca mt s quc gia trn th gii

Tiu ch nh gi h hng mt ng theo Lin X v Cng ha Lin bang Nga hin nay

Cng ha Lin bang Nga hin nay s dng su tiu ch nh gi cht lng khai thc hay chnh l mc h hng ca mt ng, bao gm

- Cng chung ca kt cu o ng

- bng phng

- nhm

- hao mn

- Nng lc thng hnh

- Kh nng tim n gy tai nn

Trn c s cc tiu ch ny, cc ngng nh gi mc h hng v tng ng l cc loi hnh bo dng sa cha ng c quyt nh nh c th hin trong bng 1.5 di y.

- 21 -

Bng 1.3 - Cc tiu ch nh gi mc h hng ca mt ng v khung phn loi cng tc bo dng sa cha.

Cc tiu ch

Cc iu kin ng tng ng cc loi hnh bo dng

Bo dng thng xuyn+ sa cha nh

Sa cha va Sa cha ln

( khi phc)

Nng cp, ci to, lm li mi

1. Cng chung ca kt cu nn mt ng

Vt yu cu

(theo cng )

Vt hoc bng yu cu

Nh hn yu cu (thiu cng )

Nh hn yu cu

2. bng phng mt ng

t hoc vt yu cu

Khng t yu cu

C th t hoc khng t yu cu (tc l khng ph thuc bng phng)

3. nhm ca mt ng

t hoc vt yu cu

Khng t yu cu

C th t hoc khng t yu cu

4. hao mn ca mt ng

Mn bng hoc t di mc cho php

Mn qu mc cho php

Khng ph thuc hao mn

5, Nng lc thng hnh thc t

Vt so vi lu lng xe chy m c ti thi im nh gi mc quy nh*

Thp hn so vi mc quy nh

6. Kh nng tim n gy tai nn

H s tai nn

Rt t

10 - 20

t

21- 30

ng k

31- 40

Nhiu

> 40

Vi 6 tiu ch trn, vic nh gi kh nng phc v ca ng l kh ton din.

Mun s dng 6 tiu ch trn phi c phng php o c xc nh cc tiu ch, phi ch n vic thit lp cc ngng qui nh t yu cu. Cc ngng ny ty thuc vo iu kin pht trin kinh t x hi mi vng min.

Cch phn loi trn c mt s tiu ch khng h c mi lin h no vi h hng ca ng (tr tiu ch bng phng), trong khi i tng ca cng tc sa cha l cc h hng trc tip trn ng Tiu ch cng chung ca kt cu, nhiu trng hp m un n hi chung Eh thp nhng mt ng vn khng h hng, nu ch xt mt tiu ch cng chung ca kt cu quyt nh ngng phn loi sa cha ln i vi mt ng l cha hon ton hp l.

Ch s nng lc phc v ca mt ng theo AASHTO

Theo kt qu nghin cu ca AASHTO ( Hip hi nhng ngi lm ng v vn ti Hoa K) qu th nghim ng AASHO th PSI (h s mc phc v ca mt ng - Present Service Index) c xc nh tu thuc nhng h hng xut hin trn b mt kt cu o ng vi cc quan h thc nghim di y:

- Vi mt ng nha:

pcRDSVPSI 01.038.1)1log(91.103.5 2

Trong :

- 22 -

C - t l tng din tch mt ng xut hin cc khe nt cp 2 (cc khe nt pht trin thnh mng li nt) v cc khe nt cp 3 (nt thnh ming v ri rc), C tnh bng ft2 trn 1000 ft

2 (tng ng 92,9 m2)

P - t l din tch mt ng b v sa (ft2/1000 ft2)

RD - su vt hn bnh xe trung bnh ca 2 di vt bnh

SV - phng sai dc dc trung bnh ca 2 di vt bnh, vi

2

1

1 n

i tbSV i in

Trong :

n l s ln o dc dc trung bnh ca 2 di vt bnh;

ii l tr s o dc ln i;

itb l tr s dc dc trung bnh ca n ln o;

ch rng SV cng ln th dc dc vt bnh thay i cng nhiu, tc l mt ng cng khng bng phng

Trong qu trnh thc nghim, AASHTO cho cc nhm chuyn gia 7-10 ngi cng i trn xe chy qua cc on ng c tnh trng h hng khc nhau. Mi chuyn gia u cho im theo thang im 5; t 4 - 5 im l rt tt, t 3 - 4 im l tt, t 2 - 3 im l trung bnh, t 1 - 2 im l km, t 0 - 1 im l rt km. Trong s chuyn gia cn phi cc thnh phn nh nghin cu v ng, li xe, hnh khch i xe.... ng thi vi vic cho im, ngi ta xc nh nh lng cc yu t SV, RD, C, P ca cc on c cho im (ly im trung bnh cng ca tt c cc chuyn gia) t lp ra c cc phng trnh hi quy (cc tng quan thc nghim) ni trn.

Do phng trnh trn ta d dng nhn thy khi mt ng hon ho tc l khi RDSV , , C, P

u =0 th PSI = 5,0 (ring vi mt ng b tng xi mng PSI = 5,41 > 5,0 l do sai s khi lp phng trnh hi quy gy ra).

Sau khi tp hp cc kt qu cho im ca cc chuyn gia AASHTO tng kt :

Nu PSI = 0: mt ng h hng n mc xe khng th i c

PSI = 2.0 : 85% ngi s dng ng khng chp nhn

PSI = 2.5: 55% ngi s dng ng khng chp nhn

PSI = 3.0: 12% ngi s dng ng khng chp nhn

PSI = 4.2 - 4.5: ng mi va lm xong

PSI = 5.0 cht lng s dng ng hon ho

bng phng ca mt ng

y l mt tiu ch c ngha quan trng nh hng trc tip n cht lng phc v ca ng. bng phng l mt tiu ch hin c cc phng php o nhanh chng v thun li v c tiu chun quc t thng nht (IRI - Internationnal Roughness Index)

Nng lc chng trn trt ca mt ng

Nng lc chng trn trt ca mt ng ( bm ca mt ng) c th c xc nh bng nhiu th nghim khc nhau. Th nghim in hnh xc nh ch tiu ny l thit b chy lc (con lc Anh). Tiu chun Vit Nam s dng phng php rc ct (nh c trnh by Chng 2 - theo Quy trnh xc nh nhm ca mt ng bng phng php rc ct 22TCN - 279 - 2001

Ch s tnh trng mt ng v phng php ng dng ca Trung Quc

- 23 -

Ch s tnh trng mt ng PCI (Pavement Conditions Index)

Cch ny xut pht t M, c v cc nc phng Ty v nay cng c Trung Quc nghin cu p dng, theo cch ny, ch s tnh trng mt ng PCI c xc nh bng cch ly s im C = 100 cho mt ng loi hon ho, tr i tng s im phi khu tr do cc loi h hng quan st thy xut hin trn mt ng :

1 1

, , ,n m

i j i j

i j

PCI C a T S D F t d

Trong :

C - im s cho ti a vi mi on ng c mt ng hon ho( khng xut hin bt k h hng no trn mt ng). Tu nc c th ly C khc nhau nhng thng ly C = 100 im;

Ti - s loi hnh h hng ;

Sj - mc nghim trng ca loi hnh h hng. C m mc , thng m = 3 mc nghim trng nh, nghim trng va v nghim trng nng (gi tt l nh, va, nng);

a(Ti, Sj, Dij) l s im phi khu tr c xc nh tu thuc loi h hng Ti, mc h hng Sj v mt h hng hay phm vi ng b khu tr Dij;

F(t, d) l h s gia quyn phi xt n khi trn mt on ng c nhiu loi h hng vi mc nghim trng khc nhau cng pht sinh. V d:

- Nu trn mt on ch c 1 loi h hng ( ch c nt li nh) v khu tr t im th h s ny l 1,0

- Nu trn 1 on c 2 loi h hng: nt li nh (tr i t1 im) v g (tr i t2 im), tc l tng s im khu tr tch lu t = t1 + t2 v s ln khu tr tc l 2 th lc phi nhn vo s im khu tr mt h s F(t, d)=0.77 ~1.0 tu theo t ( t tng s im khu tr cng ln th h s F(t, d) cng nh, c th l khi t=130 th F(t, d) =0.77 v khi t=20 th F(t, d) = 1,0

- Tng t nu trn cng 1 on phi khu tr 3 loi h hng th F(t, d) = 0.59-0.71, nu trn mt loi phi khu tr ng thi 4 loi h hng th tng s im khu tr tch lu phi nhn vi h s F(t, d)=0.5-0.7

- Nu trn 1 on phi ng thi khu tr 5 loi h hng th h s F(t, d) tu ngi nh gi quyt nh

Theo nguyn l cch thc ni trn, Trung Quc nghin cu vn dng vo iu kin c th ca Trung Quc a ra tiu ch phn loi ung phc v vic lp k hoch sa cha theo ch tiu PCI nh bng 1.4, bng 1.6 l kt qu p dng cng thc theo cch phn loi h hng nh bng 1.4 vi s im khu tr th tu thuc loi h hng, mc h hng v mt h hng nh Bng 1.5

Bng 1.4: Phn loi cc loi hnh h hng kt cu mt ng

Cc loi hnh h hng(..trn b mt

ng)

Mt ng nha Mt ng BT

xi-mng

Mt ng dm

cp phi

Nt hoc nt gy Nt dc

Nt ngang

Nt li

Nt li ln

Nt dc

Nt ngang

Nt cho, xin

Nt giao nhau(ph

- 24 -

Cc loi hnh h hng(..trn b mt

ng)

Mt ng nha Mt ng BT

xi-mng

Mt ng dm

cp phi

Nt phn nh hoi)

Nt v gc tm

Bin dng b mt Vt hn bnh xe

Ln sng

Ln, st

Ni ln

y trt

Ln st

Tri ln

Vt hn bnh xe

Ln sng

Ln

Tri ln

Mt mui luyn hoc mui luyn ngc

H hng b mt Chy nha

Ri rc

g, hn su

Mi mn

L

Nt vn, bong trc

g

H hng khe ni Pht bn

Cp knh

St m khe ni

Tri ln

Vt liu chn khe khng cn tc dng

Bng 1.5: S im phi khu tr cho mt loi hnh h hng( i vi mt ung nha)

Loi hnh h hng Mc nghim

trng

Mt h hng (%)

0.1 1 5 10 50 100

Nt li nh Nh

Va

Nng

8

10

12

12

14

17

18

22

28

30

35

45

50

55

70

60

75

10

Nt li ln Nh

Nng

5

8

8

12

16

20

25

35

32

62

40

68

Vt bnh Nh

Nng

1

3

5

10

10

20

20

30

45

60

60

80

Ln Nh

Nng

2

4

10

12

20

27

33

40

65

75

75

100

g Nh

Nng

1

10

12

17

25

30

42

52

67

77

80

100

Ni nha Khng 1 5 10 12 20 30

- 25 -

Loi hnh h hng Mc nghim

trng

Mt h hng (%)

0.1 1 5 10 50 100

phn

mc

Bng 1.6: Tiu chun nh gi phn loi lp k hoch sa cha

Phn loi tnh trng h hng

Rt tt Tt Kh Trung

bnh Km Rt km

Ch s PCI 100-91 90-81 80-71 70-51 50-31

- 26 -

Loi hnh h hng

Cn c xc nh mc nghim trng

Cn c xc nh mt h hng

n v tnh Mt (%)

v sa Mc hon ho ca ming v S(m2)

A

S

Ghi ch bng 1.7

l - chiu di cc khe nt tnh bng m

b - b rng mt ng b nh hng ca khe nt c nc, ly b=0.3m, cn trong tiu chun song ng" thit k mt ng mm" 22TCN -270-01 ca nc ta ly b=1.0m

A - tng din tch mt ng ca on ng c iu tra (m2)

x - c tm b h hng

s- din tch c xut hin hin tng h hng (m2) theo AASHTO v theo 22TCN -270-01

- Vt hn bnh c o bng thc di 4ft (1,22) t ngang vt hn bnh ri sn vt hn so vi thc; c cch 25ft (7.5m) o 1 tr s v ly trung bnh. Nu vt hn sn trong bnh t 6mm-13mm c xem l mc nh, 13-25mm xem l mc va v >25mm xem l nng;

- Nt dc, nt ngang c xp mc nh nu b rng khe nt 6mm v gy xc xe, xp mc nng nu nt rng v sn gy va p mnh khi xe chy qua.

- Nt thnh li (mai ra) c xp mc nh: cc khe nt cha lin kt vi nhau, va: cc ng nt lin kt li thnh mnh; nng : nt lan ra ngoi phm vi vt bnh v lin kt vi nhau nh da c su.

Ch rng, tiu chun nh gi phn loi lp k hoch sa cha theo ch s PCI ( v d nh bng 2-3) c th s khc nhau tu theo iu kin kinh t - x hi ca mi vng trong mt nc hoc tu mi nc. Chng hn nh Trung Quc nu PCI = 51-70 ( bng 2-3) th vi vng c iu kin kinh t x hi kh ga c th

- Tin trnh sa cha va, cn nu km th ch p dng sa cha nh. Do , cc ngng phn loi sa cha ngoi s ph thuc vo vic xy dng thng nht cc tiu ch phn loi hnh sa cha, tiu ch khu tr im tu mc v mt h hng ra cn ph thc vo iu kin kinh t pht trin ca mi vng, mi nc

Do , phn loi cng vic sa cha ng theo phng php lun, mi nc cn phi t chc vic nghin cu ring cc tiu ch ni trn, sau cc nh qun l v chuyn gia ng b phi cn c vo tnh hnh thc t nh gi tnh trng mt ng bng ch s PCI xut cc ngng phn loi cng vic sa cha ph hp vi iu kin kinh t x hi ca nc mnh.

nh gi mt ng thng qua phi hp nh gi ch s kt cu ca mt ng CIstruct (Pavememt Structure Condition Index) v ch s tnh trng mt ng CIsurf (Pavement Surface Condition Index) ca Thy in

Hai ch tiu tng hp v c trng mt ng l ch s tnh trng kt cu (CIstruct) v ch s tnh trng b mt (CIsurf), c xc nh theo cc c trng c bn

CIStruct = [A/5], c gi tr ln nht l bng 5

CIsurf = [(C+R)/15], c vi gi tr ln nht l bng 5

vi: A: Chiu su vt ln trung bnh (mm)

C: Din tch xut hin vt nt trn mt ng (%)

R: Din tch xut hin bong bt/ bong trc mt ng (%)

- 27 -

Gii php sa cha mt ng c xc nh trn c s ma trn kt hp ch s CIstruct v ch s CIsurf , nh c th hin trong bng 1.8

Bng 1.8 - La chn gii php sa cha mt ng theo CIstruct v CIsurf

CIsurf CIStruct

0 1 2 3 4 5

0 - - - - - XD li

1 - - - - - XD li

2 Lng mt Lng mt Lng mt Lng mt XD li XD li

3 Lng mt Tng cng Tng cng Tng cng XD li XD li

4 Tng cng Tng cng Tng cng Tng cng XD li XD li

5 XD li XD li XD li XD li XD li XD li

i vi cc tuyn ng c lu lng giao thng ln, gii php xc nh t ma trn trn c phi hp vi gii php sa cha xc nh c theo ch tiu gh gh mt ng xt n chi ph vn doanh l chi ph ng vai tr quan trng trong tng chi ph ca ng (xem bng 1.9)

Bng 1.9 - Gii php bo dng sa cha theo gh gh ca mt ng cho tuyn ng c lu lng xe ln

gh gh IRI (m/km) Gii php

> 10 Xy dng li kt cu mt ng

4 - 10 Tng cng mt ng

< 4 Khng cn gii php sa cha

nh gi nng lc chu ti ca kt cu o ng quyt nh chiu dy mt ng tng cng

Khi mt ng c quyt nh tng cng m bo kt cu mt ng p ng c yu cu ca ti trng giao thng, chiu dy tng cng thng c quyt nh trn c s nng lc chu ti thc t ca mt ng c xc nh bng mt phng php o thch hp vi phng php tnh ton kt cu mt ng. C hai phng php nh gi nng lc chu ti tng ng vi cc phng php tnh ton chiu dy tng cng mt ng:

- Phng php tnh ton theo l thuyt n hi, s dng kt qu o vng bng cn o vng Benkenman;

- Phng php tnh ton chiu dy mt ng tng cng theo kinh nghim, trn c s vng o bng cn Benkenman, s dng cc ton ca Vin Asphalt;

- Phng php xc nh chiu dy tng cng theo phng php AASHTO - l phng php thc nghim theo vng o c trn mt ng bng thit b FWD.

S dng phng php o xc nh cng kt cu nn ng nhanh chng, thun li (dng cn Benkenmam hoc chy ri FWD - Falling Weight Deflectometor), phi c tiu chun nh gi cng l bao nhiu l t yu cu ti thi im o tng ng vi phng php o. Do vy phng php nh gi cng chung ca nn ng hay thiu s gn lin vi phng php tnh ton kt cu o ng m mi nc ang s dng v tin cy ca kt qu nh gi cng ph thuc vo tin cy ca phng php tnh ton cng o ng.

Ch tiu nh gi mt ng km theo thit b chuyn dng xc nh - ch s v thit b Viziroad - Cng ha Php

M t s lc thit b

- 28 -

Thit b ny c s dng ghi li d liu, nhng yu t, s h hng di y:

S h hng.

Nt dc ba cp

Ln theo vt bnh xe/s bin dng ba cp

Nt mu ra ba cp .

Ming v ba cp .

g ba cp

Lp v lng ba cp

Nt ngang ba cp .

Xi mn ng vin ba cp

Xc nh cc cp s dng vi tnh ho ch s VIZIR, c th c h tr bng phn mm chuyn dng km theo thit b

Cc cng trnh

Cu

Cng (Cng hp v cng ng hay np cng)

Cc vng th ho

Vai ng (3 cp)

Thot nc (3 cp)

GPS Centre Line.

Ghi li mt im ti cao xp x 25m.

Video.

C 25m li chp nh theo c hai chiu tng v gim.

Ch s VIZIR (Is)

Ch s Vizir l ch s cht lng mt ng c pht minh bi Mr Autret, lm vic ti Trung tm Th nghim Php, s dng mt s ma trn v s hnh cy quyt nh ch s mt ng c nh s t 1 n 7, theo hnh 1.4 di y

Phm vi v mc nghim trng ca vt nt

Ch s nt

Phn loi t 1 n 5

Phm vi v mc nghim trng ca bin dng

Ch s bin dng

Phn loi t 1 n 5

Phn loi tnh trng mt ng t 1 n 7

Hiu chnh

H s h hng mt ng IS (t 1 (tt nht) n 7 (km nht))

Hnh 1.4 - Ch s Vizir v h thng phn loi

- 29 -

Ch s Vizir c xc nh trn c s ch s h hng dng nt (If) v ch s h hng bin dng (Id) c phi hp vi nhau v hiu chnh c gi tr t 1 n 7 tng ng vi mc h hng ca mt ng tng dn.

Ch s h hng nt c xc nh theo 3 cp tng dn t 1 n 3, theo mc rng ca vt nt vi mc pht trin vt nt cng theo 3 cp l % ca din tch mt ng xut hin nt. Ma trn ch s h hng nt c thit lp vi 5 gi tr t 1 n 5 theo mc nghim trng ca h hng dng nt (xem hnh 1.8)

Tng t l i vi ch s h hng bin dng. Ch s h hng bin dng cng c phn cp tng dn t 1 n 3 v ng vi mc pht trin ca h hng bin dng c tnh bng % h hng bin dng so vi tng din tch ca mt ng (xem hnh 1.8)

Ch s h hng ban u c xc nh trn c s ch s h hng nt v ch s h hng bin dng v sau c hiu chnh theo mc v t l din tch mt ng h hng c sa cha (cc vt v) a ra h s h hng Vizir Is (hnh 1.5)

Hnh 1.5 - Nguyn l v trnh t xc nh ch s h hng Vizir

Ch

s h

h

ng n

t

Mc

0-10%

10% -

50% >50%

1 1 2 3

2 2 3 4

3 3 4 5

Ch

s h

h

n

g b

in d

ng

Mc

0-10%

10% -

50% >50%

1 1 2 3

2 2 3 4

3 3 4 5

C

h s

h

hng th

n

ht

If

Id

0 1-2 3 4 - 5

0 1 2 3 4

1-2 3 3 4 5

3 4 5 5 6

4-5 5 6 7 7

Hiu

chn

h ch

s h

h

ng

Mc

0-10%

10% -

50% >50%

1 0 0 0

2 0 0 +1

3 0 +1 +1

Is = 0 ~ 7 ly Is = 7 nu > 7

- 30 -

Lu , khi xc nh ch s h hng nt, c th xc nh vi nhiu loi hnh nt khc nhau, kt qu ch s nt s ly theo loi hnh nt no c ch s h hng nt ln hn.

nh gi cht lng mt ng theo ch s Vizir

Khi xy dng k hoch bo dng ng, ngi ta phi ng thi xc nh ch s Vizir v gh gh (IRI) ca mt ng phi hp a ra gii php bo tr tng ng vi tnh trng ca mi on tuyn.

Cht lng mt ng nh gi theo ch s Vizir Is

Is = 1 2: Nt t hoc khng nt hoc bin dng; tnh trng mt ng tt, khng cn bo tr ngay.

Is = 3 4: Nt mt cht hoc khng bin dng hoc bin dng m khng nt; tnh trng mt ng cp trung, cn phi bo tr nhanh m khng cn phi cn nhc thm na

Is = 5 7: Nt v bin dng trn phm vi rng; tnh trng mt ng km cn phi bo tr ln hoc tri thm

1.5 - Mt s cng ngh c p dng hiu qu trong bo tr mt ng nhng cha c s dng rng ri ti Vit Nam

1.5.1 - X l vt nt

Phn ni dung ny trnh by mt s cng ngh trong sa cha v bo dng ng b, m

khng mi so vi cng ngh ca cc nc pht trin v mt s nc trong khu vc, nhng cha

hoc ang trong giai on th nghim m cha c tiu chun thi cng nghim thu chnh thc ca

Vit Nam, v cha c trong ni dung Tiu chun k thut ca Chng trnh Bo tr Mng li

Quc l NPP. Phn ni dung ny c bn c tham kho t ti liu ca Vin Asphalt.

Lng bt vt nt

Lng bt vt nt khng phi l mt cng ngh mi v hin i. Lng bt vt nt nhm hai mc ch:

- Chng nc thm xung cc lp kt cu pha di, lm gim cng kt cu o ng

- Chng cc vt liu khng thch hp ri chn vo khe nt, gy pht trin vt nt khi vt liu mt ng gin n, co ngt khi nhit thay i.

C th lng bt vt nt bng cc loi vt liu nh va bitum, bitum lng hay nh tng bitum. Khi cc vt nt cn c duy tr trng thi c trm kn th mt ng gi c n nh. nhng khi vt nt b n ra hay co li qu ln, lm mt hiu qu ca vt liu trm v vt nt cn c trm li. Trong cc vng kh hu c bin thay i nhit ln, vic trm li vt nt ny cn c tin hnh thng xuyn hng nm. Lng bt vt nt c chi ph tng i thp, nhng khi thc hin thng xuyn l gii php ko di tui th ca ng kh hiu qu.

Theo kinh nghim s dng ca nc ngoi, tui th ca vt nt sau khi lng t c t 3 n 8 nm ph thuc vo loi vt liu s dng, tnh trng mt ng v k thut s dng.

Cng ging nh gii php thot nc, lng vt nt l hot ng bo dng quan trng. Nhiu dng h hng mt ng s nghim trng hn nu cho php nc ngm vo kt cu mt ng. Gi cho nc khng thm vo mt ng l gii php cn thit lm chm qu trnh xung cp ca mt ng hay l trnh mt ng h hng nghim trng hn.

Cc vt nt dm nh l cc vt nt c chiu rng nh hn hoc bng 3mm, l cc vt nt do qu nh nn rt kh trm. Nu vt rn nh ny xut hin trn phm vi rng, cn phi s dng gii php lng li b mt ng, c th bng cc gii php phun nh tng nha ng, lng nha mt lp, lng va nha hay lng nha ri ct. Gii php x l b mt chn lc cn s dng vt liu dnh bm c linh hot ( chy) tt c th lp knh cc vt nt dm.

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Cc vt nt nh l cc vt nt c b rng t 3mm n 12.5mm v thng c c rng n hoc ln hn 6mm to ch cho vt liu trm. Cc vt nt c lm sch v chn kn. Nu vt nt su hn 50 mm, c th t thanh chn bo v vt liu trm.

Cc vt nt trung bnh l cc vt nt c kch thc rng t 12.5 mm n 19 mm. Vi khe nt ny khng cn c rng m ch lm sch v chn kn bng vt liu trm. Thanh chn cng c t trc khi trm vt nt nu vt nt su hn 50mm

Cc vt nt ln l cc vt nt rng hn 19mm, c th c chn kn bng va nh tng bitum, hn hp b tng asphalt ct theo phng php nng.

Cc loi vt liu c th s dng cho mc ch lng bt vt nt bao gm:

- Bitum lng loi MC-30, 70 v 250

- Nh tng bitum:SS-1; SS-1h; CSS-1; CSS-1h.

- Bitum ci tin bng ph gia

- Hn hp b tng asphalt nng, va bitum v hn hp b tng asphalt ct nng

- Bitum (cc loi) ri ct thm.

Trnh t lng bt vt nt

Lm sch cc vt nt s dng p lc kh nn cao, my thi ct, my qut, thi kh nng hoc pht nc p lc cao.

Lm sch vt nt l bc thc hin quan trng, v nu vt nt nu khng sch v kh th vt liu trm vt nt s khng dnh c vo thnh ca vt nt. Phng php lm sch hiu qu nht l s dng my thi ct, nhng l phng php th cng. Thi kh nng c thc hin bng u thi kh nn nng kt ni vi my nn kh. Sau khi khe nt c lm sch, cn phi kim tra chiu su nt t thanh chn h tr i vi cc vt nt rng c chiu su ln. Thanh chn cn lm bng vt liu c kh nng nn, khng b trng n, khng thm ht vt liu v c nhit chy hn hn nhit chy ca vt liu chn khe. Thanh chn nn rng hn khe nt khong 25% khng b trt hay tri trong khe nt sau khi c chn.

Sau khi chun b xong, vt nt c chn bng nha trng thi lng bng vic s dng u rt cm tay. Lng vt liu chn ch c rt va y khe nt. Vt liu chn khe tha cn c qut sch bng loi chi thch hp v khe chn c ph mt lp ct thm.

Trnh t ny c p dng chn cc loi khe nt nh, khe nt trung bnh v khe nt ln. Ring vt nt dm do qu hp nn vt liu chn khe khng th thm xung khe vt. Vng xut hin vt nt dm nn c lng nha mt lp.

Cn phi thn trng khi p dng gii php lng vt nt i vi iu kin thc t ca Vit Nam, khi m hnh thc h hng nt ti Vit Nam c nguyn nhn khc vi cc nc pht trin khc, thng lin quan n cng cc lp mng, ngha l cng tng th ca kt cu o ng. Trong trng hp ny, gii php trm v vt nt khng c hiu qu.

1.5.2 - X l b mt ng c

X l b mt mt ng bng nha l gii php a nng, c s dng rng ri trong xy dng v bo tr mt ng ri nha. C mt s gii php x l b mt m i vi Vit Nam hin nay, ph bin l phng php lng nha nng, vi lng mt lp, hai lp v ba lp, v hin c tiu chun v bt u s dng nh tng bitum lng.

Lng nha c coi l gii php kinh t, d thc hin v c kh nng ko di tui th ca mt ng. Lng nha lm kn mt ng v ko di tui th ca mt ng, tuy nhin, mi phng php lng nha c th c cc mc ch c th khc nhau. Lng nha khng tnh vo kt cu mt ng, nhng c th to mng chng nc thm xung cc lp kt cu pha di v to lp hao mn. V vy, lng nha tuy l gii php a nng to lp b mt ng tt, nhng khng phi l

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gii php cho tt c cc h hng, c bit l h hng v kt cu ca mt ng. HIu c cc u im v cc hn ch ca cc gii php x l b mt l cn thit c th p dng gii php ny mt cch hiu qu nht. Trong mi trng hp c th, cn nghin cu v nhu cu giao thng, ng thi vi vic nh gi tnh trng mt ng xem c th p dng c gii php x l b mt ng hay khng.

Trong phn ni dung ny, ch gii thiu v cc phng php x l b mt m hin cha c s dng, cng nh cha c tiu chun k thut thi cng nghim thu c ban hnh Vit Nam.

Phun nh tng bitum ln b mt ng (Fog Seal)

Phun mt lp mng nh tng phn tch chm pha long vi nc ln b mt ng. C th s dng nhiu t l pha khc nhau - n t l mt phn nh tng trong nm phn nc, nhng t l ph bin s dng l 1:1. Cc loi nh tng c s dng l SS-1, SS-1h, CSS-1, hoc CSS-1h.

Phun nh tng c th c xem nh l mt gii php bo dng ty mc ch s dng k thut ny. Tuy nhin, y khng phi l mt bc trong lng nha hay lng va nha. K thut ny c th s dng hi phc li b mt mt ng b tng asphalt ri nng c b kh v gin do lo ha, trm vt nt v cc l rng trn b mt v ngn chn mt ng b bong bt.

Nh tng c ha tan trong nc c nht kh nh nn c th chy vo cc khe nt v cc l rng trn b mt ng d dng. Nh tng trng thi ny ng thi cng c th bao bc c cc ht ct liu trn b mt ng.

K thut ny c th lm ko di tui th ca mt ng v lm chm li yu cu bo dng ln hay ci to mt ng.

Tng lng nh tng pha long c s dng trong k thut ny l 0.45 - 0.7 lt/m2. T l s dng chnh xc c xc nh trn c s cu trc, kh b mt v t l b mt ng b nt hay b bong bt. Trnh s dng t l ln v c th gy hin tng trt v dnh bnh xe. Trong trng hp phun tha vt liu, cn khc phc bng vic ri mt lp ct mn v sch thm ht vt liu tha.

Cng tc phun ph b mt c thc hin vi iu kin mt ng kh, sch, nhit khng kh ti thiu l 160C, thi tit kh ro. Cn bo dng mt ng khng cho phng tin giao thng i li cho n khi nh tng phn tch xong v bitum thm ht xung b mt ng. Thi gian bo dng ny c th thay i t khong 1 h trong iu kin kh hu nng v kh ro n 3h hoc nhiu hn trong iu kin kh hu mt v m. C th s dng lu bnh lp lu ln b mt lm gim thi gian phn tch.

Phun cht phc hi bitum c trong hn hp mt ng

Chng ta bit, cht kt dnh bitum gm c hai thnh phn, asphaltenes l thnh phn rn v maltenes, l thnh phn lng. Trong qu trnh lo ha, maltenes b xy ha v t l thnh phn lng v thnh phn rn gim i v lm cho hn hp nha b kh v gin. Cht phc hi asphalt l cc loi nh tng ca thnh phn maltenes. Theo tiu chun k thut (ASTM D 4552), loi nh tng ny c th ch bao gm maltenes hay l hn hp maltenes vi lng khc nhau asphaltenes.

Cng ging nh k thut phun nh tng bitum b mt, cht phc hi bitum c trong hn hp mt ng c s dng nh l gii php bo dng mt ng. T l ti ln mt ng ng vai tr quyt nh. Cn phi th nghim trn on ti th xc nh lng ti ph hp m bo hp th xung mt ng c. Thc hin ti sau cn c kim sot m bo ng hm lng ti c xc nh.

Cht phc hi bitum mt ng c c th s dng trong trng hp ti ch mt ng lm dung mi ti ch phc hi lng bitum c trong hn hp ti ch.

Lng nha gm to nhm (Chip Seal)

Ti nha gm thc cht l k thut lng nha nh c hiu theo ngha lng nha truyn thng l gii php bo v mt ng di nh hng ca nh nng mt tri v nc. Mt tc dng na

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ca k thut ny l tng cng kh nng chng trn trt ca mt ng do ct liu gm trn b mt ti to cu trc nhm ca mt ng.

K thut truyn thng nh bit bao gm cc lp cht dnh kt (bitum nng hoc nh tng) c ph bng ct liu ng kch c, theo mt lp, hai lp hay ba lp. Cng ngh mi mun cp y chnh l cht dnh kt c ci tin v thit b lng t ng, hin cha s dng Vit Nam.

Cht dnh kt cn c la chn trn c s:

- Nhit ca b mt lng

- Nhit khng kh

- m v gi

- Tnh trng b mt lng

- Loi v tnh trng ca ct liu lng s dng

Loi cht dnh kt c xem l thch hp s dng nu:

- C linh ng ( chy) phun v bao bc u trn b mt lng, nhng phi nht dnh u, khng ng li thnh cc vng trn b mt ri v khng chy ht ra khi phn mui luyn ca mt ng.

- Sau khi ti, cht dnh kt cn li c lm m ct liu lng

- Cht dnh kt c kh nng ng c v pht trin dnh bm nhanh chng

- Sau khi c lu ln v ng c, tt c cc ct liu lng u dnh cht vi b mt ng, khng b bong khi c xe chy qua

- Cht dnh kt c ti vi t l khng gy hin tng chy nha mt ng hoc gy trt b mt.

Trong iu kin kh hu kh, nng bitum c c th s dng c, nhng tt nht nn chn nh thng bitum phn tch nhanh. Cc loi cht dnh kt thch hp cho lng mt ng l cc loi nh tng RS-1 v RS-2; CRS-1 v CRS-2; MS1 v cc loi nha c, nhng c phn loi theo Superpave l PG46-34; PG52-28; PG58-28; PG64-22 v PG-70-22. Tuy nhin, ti liu ca Vin Asphalt lu rng, khi s dng nha ng c theo phn loi ca Superpave (PG), ct liu lng cn c nung nng trc khi ri. Ngoi ra, hin nay ngi ta cn s dng cc loi bitum c hoc nh tng c ph gia polime cho k thut lng nha trong xy dng v bo dng mt ng.

Thit b lng nha t ng bao gm my ti bitum v ri ct liu.

My ti bitum l thit b quan trng trong k thut lng nha, gip ti bitum u vi t l chnh xc theo nh c xc nh trc. My ti bitum gm c xe ti hoc xe ko theo ch bn cha bitum dung tch t 3,000 - 20,000 lt. Hu ht cc my ti nha u c lp t h thng un nng t ng duy tr nhit ca cht dnh kt khi ri. My ti c th bao gm h thng bm t hnh bm c cc loi cht dnh kt t dng ngui nh nh tng bitum n loi bitum c c un nng n nhit ng vi nht phun. H thng phun bao gm thanh gn u phun phun cht dnh kt xung mt ng, vi chiu rng mt lt c th thay i t 1.8 m n 9.1 m, ph thuc vo chiu rng cn phun v cng sut bm.

Mt trong nhng b phn quan trng nht ca my ti l thanh phun. t c kt qu phun tt, kch c ca cc u phun phi ph hp vi loi cht dnh kt s dng v loi cht dnh kt la chn. Trc khi s dng, cc u phun cn c kim tra m bo thch hp v khng b h hng. Ngoi ra, gc ca trc dc vi m ca u phun cn c iu chnh m bo cc u phun phun va trong phm vi nht nh, khng trm ln nhau v cng khng c khong li gia. Chiu cao lp thanh phun cng cn lu , v n cng s nh hng n khong phun v t l phun.

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Thit b ri ct liu l b phn quan trng th hai sau my ti cht dnh kt, m bo ri mt lng ct liu u trn b mt vi t l yu cu. C ba loi thit b ri ct liu. Mt l thit b ri ko theo gn trc tip vi xe ti. Loi th hai v thit b ri c hc, cng l thit b ko theo nhng c bnh h tr ri ct liu. Loi th ba l loi thit b ri c hc t hnh, c th ko xe ti ch ct liu v cung cp nng lng vn hnh ri.

Thit b ri ct liu c th iu chnh tc ca cc bng chuyn cp liu v do iu chnh c dng ct liu vo trong phu thch hp vi dng ct liu c ri t phu. Cc sensor iu chnh mc vt liu trong phu rt, kt hp iu chnh tc ca bng chuyn s m bo vn hnh t l ri ng nht.

Lng va nh tng bitum (Slurry Seal)

Va nh tng bitum l hn hp bao gm ct cp phi tt, bt khong (nu cn), nh tng bitum v nc, dng x l mt ng. K thut ny c s dng cho c bo dng d phng v bo dng sa cha cho mt ng ri nha, nhng khng lm tng cng ca kt cu mt ng. Cc phn mt ng h hng v kt cu hoc c cng km u cn phi c sa cha trc khi lng va nh tng bitum. Cc dng h hng nh ln vt bnh, li lm, h hng mp ng, thiu mui luyn, gn sng hay tt c cc phn khng bng phng khc ca mt ng lm gim cht lng xe chy u phi c sa cha trc khi lng va nh tng bitum.

Lp va lng trn mt ng rt c hiu qu do lm gim cc h hng b mt lin quan n hin tng xi ha bitum lm hn hp mt ng ha gin. Lp va lng cn c th trm kn cc vt nt, ngn chn bong bt ct liu, to lp b mt kn nc v ci thin kh nng chng trn trt v tnh trng mt ng. K thut lng va c mt s u im:

- thi cng nhanh chng

- khng cn ct liu lng

- to b mt tt cho k cc vch v iu khin giao thng trn mt ng

- c kh nng sa cha b mt gh gh t

- t nh hng n cao va

- khng yu cu iu chnh cc h ga thot nc hay cc cng trnh k thut khc

- ci thin m quan b mt ng.

Vt liu s dng cho lng va nh tng bitum

Ct liu s dng cn sch, c gc cnh, bn v c cp phi tt. Cc tiu chun tng ng i vi ct liu cho lp va nh tng bitum c tm tt nh sau:

- ng lng ct ( AASHTO T 176) 45

- Ch s LogAngeles (AASHTO T 6) < 35

- Thnh phn cp phi yu cu: c th hin trong bng 2.4

Bng 1.10 - Thnh phn cp phi ct liu s dng lm va nh tng bitum

Loi va I II III

Cc iu kin s dng chung

Trm vt nt v lng nh

Dng lng, to b mt nhm trung bnh

C th lng mt hoc 2 lp, to b mt c

nhm cao

C sng (mm) Phn trm lt sng tch ly (%)

9.5

4.75

100

100

100

90-100

100

70-90

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Loi va I II III

Cc iu kin s dng chung

Trm vt nt v lng nh

Dng lng, to b mt nhm trung bnh

C th lng mt hoc 2 lp, to b mt c

nhm cao

C sng (mm) Phn trm lt sng tch ly (%)

2.36

1.18

600 m

300 m

150 m

75 m

90-100

65-90

40-65

25-42

15-30

10-20

65-90

45-70

30-50

18-30

10-21

5-15

45-70

28-50

19-34

12-25

7-18

5-15

Hm lng bitum, % so vi KL ct liu kh

10-16 7.5-13.5 6.5 - 12

T l ri (kg/m2), theo KL ct liu kh

6-10

(3 - 5.5)

10-15

(5.5 - 8)

15(8) hoc nhiu hn

Va nh tng bitum loi I c s dng trm cc vt nt ln v c th dng ri x l b mt trc khi ri gm hoc ri b tng asphalt. Ngoi ra, ri va nh tng bitum loi I cn c th dng lm lp b mt cho cc ng c lu lng xe thp, ng bng cho cc my bay loi nh, cho khu vc xe v gia c l.

Va nh tng bitum loi II c cp phi ct liu s dng rng ri nht. Nh tng bitum loi II c s dng lng sa cha phn mt ng b bong bt, lo ha do xi ha, mt mt ct liu v ti to nhm mt ng. Lng va nh tng bitum loi II c s dng cho ng c lng giao thng trnh bnh ph thuc vo cht lng ct liu s dng v vo thit k kt cu mt ng.

Va loi III c s dng sa cha b mt ng cho lp mt trn cng ca kt cu o ng nhiu lp cho ng c lu lng xe ln to b mt c nhm tt.

Cht dnh kt c s dng lm va nh tng bitum c th l nh tng loi SS-1, SS-1h, CS-1 hoc CSS-1h. Cng c th s dng nh tng phn tch nhanh trong trng hp cn thng xe nhanh. Trong trng hp cn thit c th b sung ph gia dng lng hay dng bt iu chnh thi gian phn tch ca hn hp va.

Trong hn hp va nh tng, cn thm vo mt s lng nh bt khong nh l vi thy ha, bt vi, xi mng Porlant, tro bay h tr s phn tch v n nh ca va. Lng nc s dng cn phi cn bng v cn i vi cc thnh phn khc trong hn hp.

Thit k thnh phn hn hp va c th tham kho theo tiu chun ASTM D 3910 - Hng dn thit k, th nghim v thi cng va nh tng bitum.

Qui trnh thi cng

Thit b thi cng

Thit b sn xut va nh tng l thit b trn lin tc t hnh, c kh nng xc nh trc chnh xc lng ct liu, bt khong, nc v nh tng a vo bung trn v x mt lng chnh xc va ri ln mt ng c chun b sn. C ch hot ng ca thit b trn hon ton tng t nh thit b trn theo m khc. Thit b c lp t nh b phn ko theo bao gm cc b phn ring bit nh bn cha, cc hc cha v b phn cn t ng xc nh lng cc vt liu thnh phn l ct liu, nh tng, nc v bt khong. Thit b cng bao gm b phn trn l bung trn

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n hay bung trn kp v x dng vt liu va lin tc t bung trn xung hc ri. Hc ri c lp t dng c ri dng chi mm v mt thit b iu chnh chiu rng ri. Cc hc ri c th c lp t cc thanh khoan thy lc rut g xoay trn cho hn hp linh hot v ri u hn hp trn chiu rng ri. Thit b c lp t theo hnh thc nh vy s gip s dng c nh tng phn tch nhanh.

Va nh tng bitum c ri vi chiu dy thay i t 3mm - 6 mm mt cch trc tip qua h thng lin hon trn - vn chuyn - ri lin tc trn mt ng.

Chun b hn hp

Trn cc loi vt liu thnh phn ca va nh tng bitum theo cc t l khc nhau trong phng th nghim la chn c thnh phn hn hp thit k.

Sau khi t l hn hp c xc nh trong phng th nghim, cng tc ri th c th c thc hin vi mt hay nhiu hn cc loi hn hp. Cc on th nghim phc v mc ch kp:

- Th h thng cp liu, cn v kim sot trong thit b thi cng lin hon. Dng ct liu c xc nh vi cc m ca cng cp liu khc nhau v lng nh tng bm theo t l ct liu t bng chuyn cp liu.

- m bo thnh phn ca hn hp va nh tng bitum c xc nh l hp l.

Ri hn hp

Trc khi ri hn hp va, b mt ng cn phi c lm sch bi, bn rc, cy c v cc loi vt liu c hi khc. Lp dnh bm bng vt liu nh tng cng loi vi vt liu trn trong hn hp c ri trc khi ri hn hp va. Vi mt ng lm mi, ri va nha to nhm ln trn b mt b tng asphalt mi, c th khng cn ri lp dnh bm.

Hn hp va ng u l rt quan trng, nu hn hp khng c trn u c th gy ra hin tng tha nha cc b v gy ra nhiu dng h hng i vi mt ng.

Trong qu trnh ri, cn thn trng i vi cc khe ni ngang v khe ni dc trnh ri li, ri trm ln phi ct gt phn ri tha. Tt nht l l ri phn khe ni khi m vt ri bn cnh va phn tch xong hay cn trong trng thi na chy. c b mt hon thin tt v bn, cc khe ni ln c x l khi vt ri bn cnh trng thi phn tch mt na. Cc nguyn tc ri tng t nh ri hn hp b tng asphalt thng thng khc.

Lu ln

Lu ln lp va nh tng bitum thc hin trong cc khu vc cn thit nh l ng ln ng bng sn bay, khu vc xe ti v nt giao ct c lu lng giao thng ng, l cc khu vc thng c lc ngang do r, phanh xe hay tng tc. lu ln hiu qu, c th dng lu bnh lp 5 tn vi p lc bnh 345 kPa. Lu ln c bt u ngay sau khi nc sch thot ra khi hn hp va c kim tra bng cch p giy ln trn hn hp va ri v giy khng i mu. Lu ln cng ch cn thc hin khi chiu dy va ln hn 6mm.

Bo dng/ iu khin giao thng

Va nh tng bitum ch c ri trong iu kin nhit ti thiu l 100C v khng ma. Thng xe ch c cho php khi hn hp va ng cng hon ton. Tuy nhin, s dng giao thng vi mc ch m nn, c th cho php thng xe ngay khi nc sch thot ra khi hn hp (kim tra bng cch t giy ln trn b mt va m giy khng b i mu), nhng phi iu khin xe chy chm u, khng phanh hay tng tc hoc r t ngt.

Ri hn hp ph mng

y khng hon ton l cng ngh mi trong iu kin ca Vit Nam, v c on th nghim v tiu chun cho lp b tng asphalt siu mng - Quy trnh cng ngh thi cng v nghim thu lp ph mng b tng nha c nhm cao - 22TCN - 345 - 06. Tuy nhin, lp ph mng theo tiu chun

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ca hin hnh ca Vit Nam s dng nha ng c ph gia polime dng c nng. Phn ni dung sau y gii thiu tm tt v yu cu vt liu v thi cng theo Ti liu hng dn ca Vin Asphalt cho lp siu mng s dng cht dnh kt l nh tng bitum c ph gia polime.

Lp ri siu mng cng tng t nh lp ri va nh tng bitum nhng c mt s iu ngoi l. u tin l s dng cht dnh kt c ph gia polime. Th hai, do cht dnh kt c ph gia polime cho hn hp cng hn nhiu v chiu dy ri gii hn l in. ( khong 2 cm). Cng do cng ca hn hp, yu cu thit b trn chc chn hn v h thng thanh ri kp xon rut g c th san dng hn hp u trong hc ri.

Hn hp cho lp ph mng bao gm nh tng bitum c ph gia polime, ct liu c cht lng cao, bt khong, cht ph gia v nc. Hn hp thng thng yu cu 82-90% ct liu v cc thnh phn vt liu sau y c tnh theo khi lng ct liu kh:

- 1.5 - 3.0 % xi mng Porlant s dng nh l bt khong

- 5.5 - 9.5 % b cht dnh kt (bitum ph gia polime).

Yu cu vt liu

Cht dnh kt l nh tng bitum c ph gia polime phn tch nhanh. Ct liu c s dng cho lp ph mng c yu cu nh ct liu cho hn hp va nh tng bitum loi II v loi III c trnh by trn. Bt khong l xi mng Porlant hoc vi thy ha. Loi v khi lng bt khong c xc nh nh thit k thnh phn trong phng th nghim. iu chnh lng bt khong trong phm vi 1% t c ng c v thi gian ng c ca hn hp. Cc nh gi vt liu v thit k hn hp theo Hng dn ca Hip hi Quc t vt liu va lm b mt ng - Hng dn thit k hn hp ph mng A143

Thit b

Thit b trn

Lp ph mng c trn trong thit b trn lin tc, c th cp liu mt cch chnh xc cc thnh phn ct liu, nh tng bitum, bt khong, ph gia kim sot phn tch vo thit b trn v x hn hp ph trn vo hc lin tc.

Thit b ri

Hn hp c dn u trong hc ri bng h thng hai thanh xon rut g.

Mt trong nhng ng dng ca hn hp mng l lng vt ln bnh xe v hn ch bin dng do. Hn hp c th s dng v cc vt ln v cc ln lm trn mt ng. Vt ln su in (12.7 mm) hoc su hn c th c v ring r vi loi hc ri dnh ring cho v vt ln vi chiu rng v t 1.5 m hay 1.8 m. Vt ln su hn 37.5 mm c th yu cu nhiu lp ri khi phc li hnh dng mt ct ngang ng. Cc vt liu v vt ln cn c ng c t nht 24h trc khi ri vt liu b sung thm.

iu kin thi tit

Khng thi cng lp ph mng khi c nhit mt ng v nhit khng kh di 100C v tri ma, nhng c th thi cng trong nhit khng kh ln hn 70C v tri nng.

Chun b b mt

Trc khi ri lp ph mng, b mt ng c cn c lm sch v chun b cn thn. Cc vt nt cn c lm sch v trm kn. B mt ng cn c qut sch ht rc bi v cc cht c hi khc.

Lp dnh bm c yu cu trong mt s cc trng hp s dng cc loi nh tng phn tch chm CSS v SS pha long vi t l 0.19 - 0.38 lt/m2.

Thi cng lp ph mng

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Sau khi chun b b mt, lp ph mng c ri bng my ri chuyn dng. Trnh t ri v x l mi ni tng t nh ri b tng asphalt thng thng.

Lng va gm (Cape Seal)

Lng va gm c th xem nh l lng mt lp, ngha l ri mt lp ct liu ln trn lp va nh tng bitum. Mt vn cn thit i vi k thut ny l vn tha va, v c th nh hng n cu trc nhm ca mt ng.

Yu cu vt liu va nh tng nha ng nh c trnh by phn trn v yu cu ct liu tng t nh i vi ct liu dng cho lng nha.

Lng vt liu s dng cho mt lp lng va gm nh sau (xem bng 2.5)

Bng 1.11 - Yu cu lng vt liu s dng cho k thut lng va gm

Chiu dy ri 12.5 mm Lp dnh bm (l/m2) Ct liu (kg/m2) Va nh tng (kg/m2)

Nh tng (RS-2; CRS-2)

1.4-2.0

Ct liu ri lng Kch c 12.5 mm - 4.75 mm

14-16

Va lng loi I 3-5.5

1.6 - Gii thiu kt qu nghin cu v cng ngh v vt liu trong bo dng sa cha ng thuc chng trnh SHRP

Chng trnh nghin cu trong lnh vc bo dng sa cha mt ng (b tng nha, b tng xi mng) ca SHRP l c s xem xt kh nng ng dng, bao gm cc bo co nghin cu cui cng:

- Qui trnh nh gi gii php bo dng sa cha bo dng mt ng: bo co nghin cu SHRP-H-322;

- Hng dn thc hin sa cha mt ng nha : bo co nghin cu SHRP-H-348;

- Nghin cu v th nghim vt liu mi v cng ngh trm - v vt nt trn mt ng b tng nha: bo co nghin cu SHRP -H-354;

- Nghin cu v th nghim vt liu mi v cng ngh v g trn mt ng b tng nha: bo co nghin cu SHRP -H-353;

- Hng dn thc hin sa cha mt ng b tng xi mng: bo co SHRP - H-349);

- Nghin cu v vt liu mi sa cha h hng mi ni v vt nt trn mt ng b tng xi mng: bo co nghin cu SHRP -H-355;

- Nghin cu v vt liu mi v cng ngh sa cha cc vt nt v cc b trn tm mt ng b tng xi mng: bo co nghin cu SHRP -H-356.

1.6.1 - Kt qu nghin cu ca SHRP v cng ngh bo dng phng nga cho mt ng b tng nha

Cc hnh thc bo dng phng nga cho mt ng b tng nha bao gm:

- Lng bt vt nt trn mt ng b tng nha

- V g trn mt ng nha s dng vt liu mi

Lng trm vt nt trn mt ng b tng nha

Lng trm vt nt c nghin cu th nghim trn 5 hin trng, s dng 15 loi vt liu vi 8 phng php thi cng, cho vt nt ngang v vt nt dc. Khi nim lng trm vt nt bao gm:

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- Lng vt nt (crack-sealing): s dng vt liu c bit trm bt vt nt ang hot ng (vt nt rng hn 2.5 mm, c th to ln khng u gia hai mp vt nt) bng cch vt liu vo trong vt nt hay ln trn vt nt trnh nc thm qua vt nt.

- Bt vt nt (crack-filling): vt liu c bit c phun lp y vt nt khng hot ng (l vt nt c chiu rng nh hn 2.5 mm, khng c ln khng u gia hai mp vt nt) gim nc ngm xung v gia cng kt ni vt nt.

Cc hin trng th nghim gm: kh - khng lnh; kh - lnh; m - khng lnh; m - lnh (khng lnh - ngha l khng c ng bng).

Cc phng php thi cng:

Bao gm 8 phng php thi cng sa cha lng trm vt nt trn mt ng b tng nha (cc kiu sa cha k hiu t A n H) th hin Hnh 1.6.

- Kiu A: c su trung bnh v lp bng mt ng.

- Kiu B: c su trung bnh, lp y v trm theo dng bng.

- Kiu C: c nng v trm theo dng bng.

- Kiu D: Trm theo dng bng n gin.

- Kiu E: c su vt nt v trm vi thanh trn gia c.

- Kiu F: c nng v trm vi thanh vung gia c.

- Kiu G: Phun bt vt nt bng b mt .

- Kiu H: Phun bt vt nt, trm vng.

Kiu A Kiu B Kiu C Kiu D

Kiu E Kiu F Kiu G Kiu H

Hnh 1.6 - Cc phng php thc hin lng - trm vt nt trn mt ng nha

Cc loi vt liu s dng trong th nghim vi mt ng b tng nha.

Cc vt liu s dng trong th nghim ni chung c chia thnh hai nhm chnh:

- Cc vt liu nhit do, thi cng theo phng php nng v ngui.

- Cc vt liu ho nhit.

Vt liu nhit do thi cng nng: l vt liu ho mm khi nng v ho cng khi ngui m khng c thay i v thnh phn ho hc. Tnh cht ca cc loi vt liu ny ph thuc vo nhit

- 40 -

v nh hng nhiu ca qu trnh ho gi khi khai thc. Cc vt liu mi dng ny u l vt liu c ph gia nh polyme, cao su lu ho, polyme dng si.

Vt liu nhit do thi cng ngui l vt liu m qu trnh hnh thnh cng chnh l qu trnh bay hi dung mi (vi nha lng) hoc nc (vi nh tng) vo trong khng kh. Cc vt liu dng ny s dng trong nghin cu u c s dng ph gia, tng t cng l polyme hoc cao su.

Vt liu ho nhit ninh kt bng phng php ho hc, ngha l vt liu chuyn trng thi t lng sang rn nh cc phn ng ho hc. Cc c tnh c bn ca loi vt liu ny l kh nng chng li nh hng ca kh hu, kh nng n hi v linh ng c nhit cao v nhit thp. Vt liu ho nhit t c s dng cho mt ng b tng nha v tnh khng tng thch. Trong sa cha mt ng ni chung cng t c s dng do gi thnh cao. Hin cng ang c nghin cu v loi vt liu ho nhit s dng cho mt ng b tng nha m u cho kh nng s dng vt liu ho nhit cho mt ng b tng nha. Silicon l mt in hnh ca loi vt liu ny.

Cc loi vt liu s dng cho nghin cu th nghim lng mt ng b tng nha bao gm:

1) Nha ng ph gia cao su lu ho (Rubberized Asphalt)

Nha ng cao su lu ho l sn phm c dng x l cc vt nt, c bit l vt nt ngang mt ng. Nhit thi cng t 199 n 2100C. Cc nghin cu thc nghim trn cc vt nt mt ng c thc hin vi c 4 phng php A, B, C, D nh m t trn cho kt qu kh quan.

2) Nha ng ph gia cao su lu ho ci tin

C ba loi vt liu dng nha ng ci tin l Crafco RS 515, Koch 9030, v Meadows-XLM. Nhit thi cng cho vt liu XLM t 177 n 1880C v hai loi cn li t 193 n 2040C. Thi gian kim sot hn ch giao thng c p dng cho th nghim thc t l 40 - 60 pht, tuy nhin kt qa nghin cu cho thy thi gian ny ch cn 15 - 20 pht.

3) Nha ng c ph gia dng si

Hai loi ph gia dng si l Kapejo Polyester Fiber (BoniFibers) v Hercules Polypropylene Fibers (Fiber Pave 3010) trn vi nha ng. Nghin cu th nghim c tin hnh bng cch dng hn hp si Polyester trn vi nha AC-20 lng trm vt nt ngang v hn hp si Polypropyelene v nha AC 85-100 lng trm vt nt dc. Kh khn v cng ngh thi cng dng vt liu ny l vic m bo nhit thi cng hn hp khng phn tng v vic duy tr phun nha u n.

4) Vt liu Silicon t m

5) Nha ng ph gia cao su: L hn hp nha ng trn vi cao su lu ho nhit cao. Nhit thi cng t 177 - 1990C

6) Nh tng c ph gia: Loi sn phm c tn Witco CRF. Thi cng nhit khng kh, dng bt kn cc vt nt.

Nghin cu trong phng th nghim trong phng i vi cc loi vt liu

Cc th nghim nghin cu trong phng thuc chng trnh nghin cu SHRP c tin hnh theo hai giai on:

1) Giai on 1:

Cc th nghim c bn kim tra cht lng vt liu tun theo cc thng s do nh cung cp a ra. Cc th nghim v kt qu th nghim ca cc thng s ban u trong giai on ny c th hin trong Bng 1.12 v Bng 1.13

Bng 1.12- Cc quy trnh th nghim p dng -giai on 1

- 41 -

Loi vt liu Tiu chun th nghim

Nha ng ph gia cao su lu ho ASTM D3407 v D70

Nha ng ph gia cao su lu ha ci tin ASTM D3407 v D70, c ci tin

Silicon t m ASTM C603, C679, D412, D1475 v D2240

Nha ng ph gia cao su ASTM D5078 v D70

Nha ng c ph gia dng si ASTM D1577, D3939, D2256, v D882

Nh tng ASTM D244

Bng 1.13 - Cc kt qu th nghim thng s ban u - th nghim giai on 1

Th nghim Quy nh ca D3405

Hi-Spec Quy nh ca D3405

ci tin

RS 515 9030 XLM

kim ln (250C), dmm - thit b cn

90 62.6 60 n 180 75.5 114.5 148.0

chy, mm (250C) 3 0 5 1.0 0.0 2.5

dnh, m rng 50% (-20

0F)

3 chu k t

dnh, m rng 100% (-20

0F)

3 chu k t t t

% n hi (250C) 60 63.7 35 38.3 83.7 16.0

Kh nng m Khng hng t Khng hng t t t

2) Giai on 2:

Th nghim cc c tnh s dng ca vt liu. Cc tnh cht th nghim v tiu chun tham chiu ca giai on th nghim ny th hin trong Bng 1.14.

Bng 1.14 - Cc th nghim c tnh s dng ca vt liu

Th nghim Tiu chun tham chiu

Tnh cht Chun th nghim

kim ln (00F) ASTM D3407 linh ng nhit thp

Tin hnh 00F

Nhit ho mm ASTM D36 Kh nng n nh nhit cao

Un ngui Utah D133 gn kt Tin hnh 00F

ko di ASTM D36 v Utah Test

linh ng Th nghim ko di 39.20F

dnh bm ko

- Khi BTXM

- Khi BTN kh

- Khi BTN ngm nc

ASTM D3583 dnh kt/gn kt

Th nghim tiu chun s dng cc khi BTXM. Vi BTN, s dng khi BTN ngm nc hoc khng ngm nc

- 42 -

Th nghim Tiu chun tham chiu

Tnh cht Chun th nghim

M un

- 75 F

- 39 F

- 0 F

ASTM D412 linh ng Tin hnh vi tc ring 2in/pht thay cho 20 in/pht. Cc th nghim tin hnh vi 750F, 39 0F, 0 0F.

M un sau 504 gi phong ha t nhin

ASTM D412 v

ASTM G23

bn/ linh ng

Tin hnh ti 750F ch vi silicon, nha ng ci thin cao su sau cc chu k phong ho t nhin

mi mn ASTM D3910 bn

Th nghim dnh bm tiu chun

ASTM D3407 dnh kt/gn kt

Cc khi BTXM v vt liu gn kt c m phng theo ng dng s dng. Cc mu chu ko gin 100% nhit 200F v nn li theo ng dng ban u

Cng ngh thi cng v cc thit b - dng c ch yu.

Cng ngh thi cng tu thuc vo mi loi hnh lng - v s dng, bao gm c th khng y cc bc sau y:

1. Chun b mt bng, chun b cc thit b iu khin v m bo an ton giao thng. Bc thc hin ny cng ging nh khi tin hnh cc hot ng bo dng mt ng thng thng khc.

2. Ct vt nt, vi yu cu thc hin l vt nt c ct vung thnh v ct theo ng tim ca ng nt. Thit b s dng dng c li ca hoc li bo c m t y v c h thng t iu chnh chiu su ct cho ph hp.

3. Lm sch v lm kh vt nt bng mt s thit b nh:

- Thit b thi kh nn p lc cao vi p lc kh nn n 620 kPa to lung kh 4.3 m3/ pht;

- Thit b thi kh nng, vi tc dng khng ch lm sch v lm kh vt nt m cn c tc dng lm nng thnh ca vt nt. Thit b ny cung cp mt lung kh nng m khng to la u phun.

- Thit b thi ct lm kh vt nt, vi p lc nn n 690 kPa . Thit b ny thng s dng phi hp vi thit b thi kh lm sch.

- Chi qut iu khin c hc.

4. t thanh gia c

5. Trm - bt vt nt, vi nhit ph hp vi mi loi vt liu. V d, vt liu nhit do thi cng nng th nhit thi cng cn n 188 - 2000C, cn vi thi cng ngui th c th lm nhit khng kh hoc c th un nng n nhit 52 - 660C.

Mt s hnh nh v thit b s dng trong hnh 1.7.

- 43 -

A. Thit b ct dng li ca B. Thit b ct dng bo xoay

C. Thit b thi kh nn nng D. Thit b thi ct

Hnh 1.7 - Mt s thit b s dng

Kt qu cng tc theo di, nh gi

Cc hin trng th nghim vt liu mi v vt nt c theo di thng xuyn theo cc gii hn thi gian: 1 thng, 3 thng, 9 thng, 12 thng v 18 thng. Vic theo di da trn vic pht trin ca cc vt nt c v. Cc yu t v mi trng, iu kin nn ng, iu kin giao thng cng c phi hp xem xt trong cc theo di ny. Cc c trng pht trin vt nt c theo di bao gm:

1. H hng (mn, v vn, bong bt) vt liu v

2. Vt liu v b dn mng (do vt nt pht trin rng)

3. Vt v b nt rng ra bn cnh

4. Mt mt dnh bm (gia vt liu v v mp vt v)

5. Mt mt dnh kt (gia 2 mp vt v)

6. Si bt ti vt v

7. H hng mp vt v

Cc ch tiu c dng nh gi bao gm:

1. gim chiu dy ca vt v dng di trn vt nt (%) (dng cho dng sa cha B, C, D)

2. % vt v b mt mt dnh bm (dng cho dng sa cha E,F)

3. % vt v h hng hon ton (dng cho dng sa cha A,D,H)

- 44 -

4. Dng sa cha G c nh gi theo mc h hng: t, trung bnh v nhiu.

Cc dng h hng c quan st theo mc pht trin qua cc ln th st theo cc khong thi gian nh k, nh gi v mc ph hp ca vt liu trong cc iu kin khc nhau, d kin tui th ca mi loi vt liu s dng.

Cc kt qu c bn ca nghin cu th nghim vt liu v vt nt trn mt ng b tng nha ca SHRP

Cc kt qu nh gi thu c qua nghin cu th nghim cc vt liu mi v phng php thc hin cc vt v trn hin trng:

1) nh gi chung

- Hu ht cc vt v thc hin u th hin c c trng s dng tt sau 18 thng phc v. Trong 82 vt v, c 64 vt v th hin h hng ton b

- 45 -

- Tuy cc on -c thi sch bng kh p lc cao th hin cc h- hng do mt dnh bm nhiu hn mt t so vi cc on s dng thit b thi sch bng hi nng, nh-ng khng thy s sai khc nhau cn l-u i vi hai cch lm ny

4) nh gi v thit b thi cng

- Thit b bo soi xoay s dng d l nhanh hn l dng c-a thng th-ng khi dng c cc vt nt

- Thit b thi hi p lc cao s dng kh nng t ra hiu qu tt hn khi s dng thi sch v kh vt nt tr-c khi trm vt liu.

Vi cc kt qu nghin cu th nghim, H-ng dn trm, v vt nt mt -ng b tng nha -c thit lp vi cc qui nh t vic la chn vt liu v cng ngh ph thuc vo iu kin vt v, cc h-ng dn tnh l-ng vt liu cn thit, tnh ton n gi cng nh- tnh hiu qu ca gii php...

Mt s kin ngh cu SHRP i vi nghin cu v vt liu v cng ngh sa cha vt nt trn

mt -ng b tng nha

- B tr k hoch thi gian tr-c khi tin hnh sa cha : B tr thi gian nh gi tnh trng mt -ng v vt nt, cng nh- l xem xt k hoch cho vic ci to, nng cp v kh nng thc hin. Cc vic lm ny s h tr tt cho vic