Recommendation for Self-Compacting Concrete

8/3/2019 Recommendation for Self-Compacting Concrete

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Recomm enda tion for Self-Compa cting Concret e

CONTENTS

Chapter 1 Genera l

1.1 Scop e............................................................................................................................................. 1

1.2 De fin itions(Ter min ology).............................................................................................................. 4

Cha pter 2 Perform an ce of Self-Compa cting Concrete

2.1 Ge n er a l......................................................................................................................................... 8

2.2 Se lf -compa ctability ....................................................................................................................... 9

2.3 Other performances.....................................................................................................................11

Chapter 3 Materia ls

3.1 General........................................................................................................................................11

Chapt er 4 P roport ioning

4.1 Ge n er a l....................................................................................................................................... 13

4.2 P roport ion in g.............................................................................................................................. 14

4.3 F orm for expr essin g mixt ur e P roport ions .................................................................................. 15

Chapter 5 Performance verification

5.1 Ge n er a l....................................................................................................................................... 16

5.2 Ver ificat ion of self -comp act abilit y ...............................................................................................17

5.3 Verificat ion of oth er per form an ce item s..................................................................................... 19

Chapt er 6 Pr oduction a nd Control

6.1 Ge n er a l....................................................................................................................................... 19

6.2 P r odu cti on .................................................................................................................................. 20

6.3 Qu a lit y cont rol du r ing pr oduction ............................................................................................. 21

Chapt er 7 Constru ction a nd contr ol

7.1 .Ge n er a l....................................................................................................................................... 21

7.2 Conveyin g, p lacing, finish ing, cur ing an d joint s........................................................................ 22

7.3 Form wor k ................................................................................................................................... 23

7.4 Qua lity cont rol du rin g cons tr uction ........................................................................................... 24

Chapt er 8 Inspection

8.1 Ge n er a l....................................................................................................................................... 24

8 .2 In spect ion of self-compacta bility ................................................................................................ 25

8.3 In sp ection of oth er per form an ce item s ....................................................................................... 26



R eco m m en d a t i o n fo r Se l f -C o m p ac t i n g C o n c re t e

C h a p t e r 1 G e n e r a l

1 .1 Scope

(1) This Recommenda tion sha ll apply to constr uction of concret e st ru ctur es us ing self-compa cting

concrete.

(2) As t o mat ter s n ot specified herein, t he J apa n S ociety of Civil Engineers' St an dar d Specificat ion

for Design and Const ru ction of Concrete S tr uctu res sh all a pply.

[Commentary]

(1) This Recomm enda tion is ap plicable t o concret e ha ving self-compa ctabilit y with wh ich it can be

placed in th e every comer of form work without vibra tion causing n o segregat ion. The per form an ce

evaluation method of fresh Self-Compacting Concrete widely differs depending on whether

vibration is given to the concrete during placing. For this reason, the scope of this

Recommenda tion is limited to Self-Compa cting Concret e tha t can be placed with out an y extern al

forces other th an gra vity. Accordin gly, concret e to which weak vibra tion is applied t o assist t he

compa ction, as in th e case of precast product plan ts, is beyond t he scope of this Recomm enda tion.

Self-Compa ct ing Concrete n ot only increa ses th e rel iabi li ty of s t ru ctu res bu t also r edu ces th e

num ber of worker s required at the constr uction site an d str eamlines the constr uction. I n pr ecast

product plant s a s well , Self-Compa cting Concret e is highly effective in r educing th e noise as i t

requ ires no vibra tion. This Recomm enda tion specifies its perform an ce, pr ovide met hods to verify

and inspect th e performa nce, an d also ha tter s tha t r equire att ention t o ensur e its perform ance in

selecting materials, proport ioning, pr oducing, a n d pla cing. In this Recommenda tion, the term

"verificat ion" refers t o a judgment for a scerta inin g the p erform an ce before a ctua l placing, and th e

term "inspection" refers to a judgment at each sta ge of actu al placing as to wheth er t he concrete is

acceptable.

The p roport ioning m eth ods to sat isfy th e per form an ce of Self-Compacting Concrete specified in

this Recommen dation ar e provided in t he Ma nu al for Mixtur e Pr oportioning; th e producing and

placing methods in th e Manu al for P roduct ion a nd P lacement . These ma nu als provide typical

methods to ensure t he required qualit ies based on th e previous experience, but concrete m ade by

other methods m ay be used as Self-Compa cting Concrete, provided th at th ey are judged as passing

the performance verification, inspection and also satisfying the production and p1.acement

requirement s specified in th is Recommend at ion. Cur ren tly the per form an ce verification has t o be

based on various experiments s imulat ing actu al p lacement , but th e work for th e perform an ce

verificat ion can be simplified by observing t he m an ua l based on t he pr evious experience. It sh ould

be noted that when applying Self-Compacting Concrete, an engineer who understands its

propert ies and h as m ast ered th e techn ology of using such concrete should man age the procedure a teach st age of th e mixtur e proport ioning design, production, an d placement.

(2) It is import an t in th e case of using Self-Compa cting Concrete a s well to form ulat e an adequa te

str uctur al design and production/placement plan t o impar t th e required properties to th e stru cture

and execute the construction in a streamlined manner. This h specifies the performance of

Self-Compacting Concrete as a material primarily in regard to the self-compactability.

Requirements for t he per form an ce an d const ru ct ion work of the s t r uctur e should prima ri ly be

based on t he J apa n Society of Civil En gineers. Sta nda rd Specificat ion for Design an d Constr uction

of Concrete Structures (JSCE Standard Specification).



Recommendation

Fig. 1. 1 Scope of Recommendation for Self-Compacting Concrete

As t he per form an ce requir ed of a st ru ctu re, serviceability an d sa fety ar e set in considerat ion of the

funct ion of the s t ru ctur e an d th e loads a fter the s t ru ctur e is put in to service an d environment al

1oads; th e perform an ce of concrete a s a ma ter ial should then be set to satisfy th ese requirem ent s.

In this case, th e perform ance of concrete is required t o be adequa tely set to sa tisfy the perform an ce

required of the s t r uctur e an d perform an ce expected of the constr uct ion in considerat ion of th e

relat ions with t he production/placing meth ods an d deta ils of the str uctu ra l design, as th ese also

affect th e perform an ce of the st ructur e.

Self-Compa cting Concrete is char acterized by th e a doption of a concret ing met hod th at does n ot

require vibra tion dur ing placing. This Recomm end at ion specifies the performa nce required of Self-Compacting Concrete, primarily the self-compactability, and provide verification and

inspection methods. They also provide important requirements in producing and placing

Self-Compacting Concrete. The Man ua ls for Mixtu re P roportioning an d for production/placement

provide how to select a nd pr oport ion ma ter ials an d how to form ulat e the pr oduction/placement

plan, r espectively, to fulfill the requir ement s.

The work flow is as follows: th e per form an ce of concrete is det e rm ined; concret e is proport ioned

an d the constr uction plan is form ulated r eferring to th e Manu als; the verificat ion is condu cted to

check if th e concret e at ta ins th e specified perform an ce; after being confin ed tha t all perform an ce

requirem ents a re met , the concret e is placed and t hen ins pected. When th e concret e does not pass

the verificat ion, th e concrete is r eproport ioned a nd t he const ru ction plan is r eform ulat ed. When it

does not pa ss t he inspection, the const ru ction is n ot completed.

In regard t o ma tter s not specified in t his Recommen dat ion, engineers ar e required t o refer t o the

J SCE Sta nda rd Specificat ion. However, items premised on normal concreting with vibra tion

should n ot be a pplied to Self-Compa cting Concret e. These in clude th e following:

Sect ion 2 .3 (2) of th e J SCE St an dar d Specificat ion [Const ru ct ion] requir es th at th e s lum p of

concrete a t t he t ime of p lacing be not more th an 12 cm. This upp er l imit for th e s lum p is not

applicable to Self-Compacting Concrete, as its deformability is significantly increased without

impairing the segregat ion r es is tance by the addi t ion of admixtu res , such as a i r-entraining and

high-range water-reducing admixtu res a nd/or v iscosi ty agent s a s wel l as by th e proport ioning

arrangement.

Section 4.7 of th e J SCE St an dar d Specificat ion [Const ru ction] specifies the st an dar d slum p. This is



not applicable to Self-Compa cting Concret e, as it is not evalua ted by slump t esting.

Section 7.4.2 of th e J SCE St an dar d Specificat ion [Const ru ction] specifies th e sta nda rd slump of

concrete t o be pum ped. This is not app licable to Self-Compa cting Concret e, as it is n ot evalua ted by

slump t esting.

Section 7.5.2 (3) of th e J SCE St an dar d Specification [Const ru ction] prohibits lat era l tra nsfer of

p laced concret e with in formwork. This is not appl icable to Self-Compa ct ing Concret e, as i t i s

expected t o fill in form work by its own weight an d is allowed to how to an extent th at it does not

cau se segregat ion.

Section 7.5.3 of th e J SCE St an dar d Specification [Const ru ction] requir es vibra tion. This is not

applicable to Self-Compa cting Concrete, wh ich is placed int o forms wit hout vibra tion.

Section 13.5.2 of the J SCE St an dar d Specificat ion [Const ru ction] requires slu mp t esting for t he

qua lity contr ol of fresh concret e. This is not applicable to Self-Comp actin g Concret e, as it is n ot

evaluated by slump test ing.

1 . 2 Defi n i t i o n s (T e r m i n o ro g y )

The defin itions of terms used in th is Recomm enda tion ar e as follows.

(1) Self-Compa cting Concret e--Concrete h aving self-compactability.

(2) Self-compactability--A capability of concrete related to the placeability of concrete, with which it

can be un iformly filled and compacted in th e every comer of form work by its own weight with out

vibrat ion dur ing placing.

(3) Resistan ce to segregation--A propert y of fresh concrete to m ain ta in it s un iform distr ibution of

concrete ingredients against segregating action induced by gravity and extemal forces.

(4) Deforma bility--A pr opert y of fres h concre te r epr esen tin g ease of being deform ed by gravit y an d

extern al forces.

(5) Passa bil ity th rough na rr ow spaces-A capabil ity of fresh concret e to pas s with out cau sing

segregat ion th rough n ar row spaces , e.g. , between r einforcing bars by i ts own weight u s ing novibration.

(6) Placeability--A capa bility of fresh concr et e r epr esen tin g eas e of tra nsport ing, placing, filling,

compacting, and finishing.

(7) Viscosity a gent--An adm ixtur e producing an effect of increa sing th e segregat ion r esista nce of

fresh concrete. Some ar e expected t o redu ce th e fluctua tion of the fresh concret e qua lities.

(8) Fu nction--The role and ser vice of th e str uctu re a nd its m at eria ls to fulfill th e pur poses of an d

requirements for th e structur e.

(9) Per form an ce--Capa bilities of th e stru cture t o be const ru cted and its ma ter ials demonst ra ted to

fulfill the pur poses of an d r equirements for the stru ctur e.

(10) Qualities--Quantifiable properties that the structure and its materials actually possess.

(11) Verificat ion--Judgment a t a pr e-execut ion s tage a s to whet he r t he de sign ed a nd p la ne d

content s sa tisfy th e perform ance r equirements.(12) Inspection-Exam ina tion to judge as t o whether th e pr oduced or placed concret e, member s, or

stru ctur es satisfy the per form ance requirements a nd ar e acceptable.

(13) Powder-type Self-Compa cting Concret e--Self-Compa cting Concrete proportioned t o provide th e

required self-compactability not by using a viscosity agent but primarily by reducing the

water-powder rat io ( in effect increa sing th e powder cont ent ) to imp ar t a dequa te segr egat ion

resistance and using an air-entraining and high-range water-reducing admixture or

super plasticizer to impa rt high deforma bility.

(14) Viscosit y a gen t-type Se lf -Compa cting Concrete--Self-Compa cting Concrete pr oport ioned to

provide the required self-compa ctabi l i ty by the use of a v iscosity a gent to impa rt segregat ion

resistance a n d a ir -entrainin g an d h igh-range wat er-reducing admixtur e or superplas t icizer to

impart high deform ability to the fresh concret e.

(15) Combination-type Self-Compacting Concrete-Self-Compacting Concrete proportioned toprovide the required self-compacta bili ty pr imar ily by reducing th e wa ter -powder ra tio (in effect



increasing the powder content) to impart adequate segregation resistance and using an

air-entr aining a nd h igh-ra nge water -reducing admixtur e to impar t high deform ability. A viscosity

agen t is also added to redu ce th e qua lity fluctuat ion of fresh concrete, so as t o facilitat e th e qua lity

cont rol of concrete .

(16) Belite-rich portland cement-Portland cement in which the belite (dicalcium silicate) content is

not less tha n 40% an d less tha n 70%, which is h igher t ha n in modera te-heat port lan d cement .

Low-heat portland cement specified in J IS is included in th is category.

(l7) Limestone powder-Finely ground limest one, whose ma in componen t is CaCO 3 (ca lcite). Ha ving

low chemical a ctivity, it is not rega rded as a binder.

(18) Powder-A generic term for solid mat erials including cement an d t hose having a fineness equal

to or higher th an cement.

(19) Unit a bsolut e volume of coar se aggrega te-The coar se aggregat e cont ent used for pr oducing 1

m3 of concrete d ivided by the d ensity of th e coar se aggrega te in a sat ur at ed sur face-dry condition;

in m3 /m3.

(20) Unit bulk volume of coar se aggr egat e-The bulk volum e of coar se aggrega te u sed for pr oducing

1 m3 of concret e . This is determin ed by dividing the un i t coarse a ggregate cont ent by th e un i t

weight of the a ggregate.

(21) Yield value-One of th e rheological const an ts of fresh concret e, fr esh m orta r a nd fresh past e

when they ar e regarded as Bingham fluids. The minimum str ess is required for m aking th e fluid

flow.

(22) Plast ic viscosity-One of the rh eological consta nt s of fres h concret e, fresh mort ar an d fresh

paste when t hey ar e regar ded as Bingham flu ids . The magnitu de of th e cha nge in th e appl ied

str ess required for chan ging t he un it now velocity.

[Commentary]

(1) The definition of Self-Compacting Concrete used by the Japan Concrete Institute and

Architectur al Inst itute of Ja pan is adopted unchanged. However, th is Recommenda tion deal with

only concret e h avin g self-compactability.

(2) P assa bili ty th rough spaces refers to a ca pa bili ty of fresh concr et e placed in form s to pa ssthr ough na rr ow spaces such as between r einforcing bar s only by its own weight with out being

vibrator-consol idated an d with out cau sing segr egat ion. Th is capa bi l i ty can be eva lua ted to a

certa in extent by filling tests using a U-type appar at us or box-type appara tus, or by funn el tests.

(8)-(10) When selecting concrete materials and designing concrete structures according to

performance requirements, it is necessary to accurately define such terms as “function,”

“perform an ce” an d “qua lity,” which ha ve been used with out clear definitions. For th is rea son, these

term s ar e defined in t his Recommenda tion in regard to concrete ma terials an d concrete str uctures.

Though t he t erm “high fun ction” is fre quen tly used , such expres sions as “high fun ction” or “low

function” ar e not relevan t, a s “function”. refers t o such qua litat ive ideas a s “role” or “service.” Such

expressions as ''multi-fun ction'' an d ''single function'' ar e appr opriat e.

Conversely, “perform an ce” is qu an tifiable, allowing su ch express ion as “high performa nce."

The difference between “performance” and “quality” is the involvement of human interest.

“Per form an ce” is determined a ccording to the pu rp oses or dem an ds people ha ve. Such a na tu re is

more evident wh en t he ter m “requir ed perform an ce” is substitu ted. “Qua lities” ar e properties th at

things possess independent of the pur poses an d dema nds people ha ve. The qua lit ies of aggregate

can be easily under stood by this concept. However, concrete an d str uctur es ar e more complicat ed,

as t hey a re pr oducts of proportioning, str uctu ra l design an d production/const ru ction accordin g to

the performa nce selected by people. h t his case as well, th ese qualities of concret e and st ru ctur es

should be under stood as t he qua nt ifiable properties th ey possess.

(13) This is a t yp e of Self -Compacting Concrete with segr egat ion re sist an ce incre as ed by th e



reduct ion of th e wat er-powder rat io with out u s ing a v iscosi ty a gent . As a r esu l t , th e powder

con ten t becomes h igher th an in n orma l concre t e . The type o f powder t o be use d shou ld be

adequately selected in consideration of the purpose of use of the concrete. The use of an

air-entr aining a nd h ig h-ra nge water-reducing a dmixture or su perplasticizer is essential. The

water-powder ratio by volume and unit absolute volume of powder of the powder-type

Self-Compa cting Concrete dealt with in th e Man ua l for m ixtu re pr oport ioning ar e 0.85 to 1.15 and

0.l6 to 0.19 m3 /m3, r espectively.

(14) This is a type of Self-Compa cting Concret e with segregat ion r esista nce increa sed by the u se of

a viscosity agent with t he powder cont ent being low compa red with th e powder-type. The mixtur e

proportions of such concret e ar e relat ively similar t o th ose of convent iona l concret e except t ha t a

viscosity agent an d an air-entr aining and high-ra nge water-reducing adm ixtur e or super plasticizer

are used.

(15) This is a type of Self-Compacting Concrete having a reduced water-powder ratio and

conta ining a viscosity a gent. The differen ce from t he viscosity agent-type is tha t th e pur pose Of

us ing a v is cosi t y agen t is to al leviat e the f luctu at ion of fresh concret e propert ies due to th e

fluctuat ion of surface moistu re cont ent, a ggregat e gra ding, etc. The mixture proport ion of th is t ype

is similar t o the p owder t ype except for t he u se of a viscosity agen t.

(16) Belite-rich port lan d cement is a type of port land cemen t r ecently developed for concret e with a

high binder cont ent , such as h igh s t r ength concrete a nd Self-Compa ct ing Concrete. This type

exhibits not only high deform ability and high str ength developmen t in t he low water -cement r at io

ra nges but also ha s significantly lower hydr at ion exoth erm t ha n convent iona l port land cement .

The propert ies of str ength developing and hydr at ion exoth emic propert ies can be varied by t h e

combin at ion of th e belite (dicalcium silicat e) cont ent a nd finen ess. Though J IS ha s sta nda rd ized

this type as low-heat portlan d cement , belite-rich port land cement available on t he ma rk et include

th ose out of th e J IS specificat ions a nd yet h ave good qua lity. This h gener ically refer to port lan d

cement containing not less th an 40% an d less th an 70% bel i te (d icalcium si l icate); including

low-hea t port land cement , as belite-rich portlan d cement .

Regar ding (17) Limestone powder is l imest one, whose prim ar y compone nt is CaCO 3 (calcite),

pulver ized to a specific surfa ce area by Blaine of 2500 t o 8000 cm 2 /g. It can be regar ded as being

chemically iner t , th ough mar ginally active. It is often u sed when a lower hydr at ion hea t a nd/or

str ength ar e desired without redu cing the powder cont ent . Limestone powder is included in th e

categories of powder and m inera l admixtu res, but n ot included in binder s.

(18) Powder is a generic term for cement and other solid concrete m at erials h aving a fineness equa l

to or h igher th an cement . These include cement , ground gran ulated blas t-furn ace s lag , fly ash ,

silica fume, and limestone powder.

(19) a n d (20) S ince t he s elf-compactability and p a ssa bili ty t hr ough sp a ces of Self-CompactingConcrete grea tly depend on its un it absolute volume or un it bulk volum e of coar se aggregate, th ese

should be considered in mixtu re pr oportioning. Genera lly speak ing, a lower un it a bsolut e volum e

or un it bulk volum e of coar se a ggregat e lead s t o a h igh er self-compactability an d pa ssa bi l ity

th rough spaces, as well as to a lower m odulus of elasticity. An adequa te value should, ther efore, be

established t o consider t hese propert ies. It should be noted th at concret e having the sam e un it

absolute volume of coar se aggrega te m ay ha ve different coar se aggrega te content s, depending on

the density of the coarse aggregates.

(21) an d (22) Both a re r heological const an ts of fresh concret e, fresh mort ar an d fresh pa ste wh en

th ey ar e rega rded as Bin gha m flu ids . Yield values corr elat e with s lum p flow and L-type flow

values, wh ereas plastic viscosity corr elates with funnel efflux time an d tim e to 500 mm flow when

th e yield value is const an t.



C h a p t e r 2 P e r f or m a n c e of S e l f -C om p a c t i n g C o n c r e t e

2 . 1 G e n e r a l

The performance of Self-Compacting Concrete shall be adequately established to satisfy the

perform an ce requirem ents of th e str uctur e in considera tion of th e str uctur al, const ru ctiona l and

other conditions.

[Commentary]

The performance of Self-Compacting Concrete should be adequately established so that the

performa nce required of the s t ru ctur e or members can be a t ta ined and t he requirement s for t he

const ru ction can be sat isfied, in considera tion of var ious conditions. These condit ions include t he

structural conditions, such as sha pes, dime ns ions an d re inforcemen t layout a n d construction

conditions, methods of tr an sport ing, placing, finish ing an d cur ing. Wher e the per form an ce of

Self-Compacting Concret e cannot be est ablished r at iona lly set, th e str uctur al conditions an d/or

const ru ction conditions should be modified. The ma intena nce plan an d recycling plan ma y also

ha ve to be considered, as t hey affect t he r equired perform an ce of th e str uctur e, such a s dur ability.

This chapter pr ovides the perform an ce required of Self-Compa ct ing Concret e as a ma ter ial to

satisfy the per form an ce requirement of the stru ctu re.

The performance specific to Self-Compacting Concrete is the self-compactability of fresh concrete.

This is premised on a construction plan without vibration. Other performances, such as

placeability, str ength a nd dur abili ty should be esta blished similar ly to norma l concret e. These

perform ances should be established in a ccorda nce with t he J SCE St an dar d Specificat ion.

Fig. 2.1 Relat ions between Per form an ce of Self-Compa cting

Concrete and Oth ers

2 . 2 Se l f - com p a c t ab i l it y

(1) The levels of self-compactability shall be adequately established in regard to concrete

immediately just before placing into forms in consideration of the shapes, dimensions and

reinforcement conditions of th e str uctur e to be placed.

(2) The following th ree ra nks sha ll be esta blished as levels of self-compa ctability:

Ran k 1: Self-compa ctabili ty int o mem bers or port ions ha ving complicated sh apes a nd/or small

cross-sectional area s with a m inimu m st eel clear an ce in th e ra nge of 35 to 60 mm.



Ran k 2: Self-compa ctability into reinforced concrete st ru ctures or mem bers with a min imu m st eel

cleara nce in th e ra nge of 60 to 200 mm.

Ran k 3: Self-compacta bility into member s or portions ha ving lar ge cross-sectional a rea s an d a

small am ount of reinforcement with a mdn imum steel clearan ce of more t han 200 mm.

(3) It is recomm ended th at th e st an dar d self-compa cta bili ty level of genera l reinforced concrete

stru ctur es or members be Ran k 2.

[Commentary]

(1) The r an k of self-compa ctabili ty of the r equired per form an ce var ies depending on t he sh apes,

dimensions a nd reinforcement conditions. The requir ed level of self-compa cta bility can also differ

depend ing on placing condit ions, su ch as t he dr op height , flow dista nce an d lift h eight. However, it

is rat her pr actical to adequat ely establish th e const ru ction conditions, such as dr op height, flow

distan ce a nd lift h eight , according t o the concrete t o be used t ha n t o design th e concrete a ccording

to the construction conditions. Where these conditions are particularly important in the

construction plan, they may be included in the performance requirements for concrete.

(2) Ran ks 1 to 3 ar e set a s th e levels of self-compa ctability of concret e. These r an ks a re set based

on th e dimensions a nd r einforcement conditions of the st ru ctures or member s. Rank 2 is defined as

the capability of concret e with which it can be self-compa cted th rough minimum bar cleara nce of

60 to 200 mm . This norma lly corr esponds to a st eel cont ent of 350 to 100 kg/m3. Rank 1 is a level

on which concrete meets severer requirements th an Ran k 2, fillin g t he spaces to meet th e

minimum cover depth an d clear an ce specified in th e J SCE St an dar d Specif icat ion. Ran k 3 is a

level on wh ich concrete meets easier conditions th an Ran k 2, demonstr at ing self-compactabili ty

where the minimum bar clear an ce is more th an 200 mm a nd ma ximum steel cont ent is less than

100 kg/m3.

(3) In normal concrete stru ctur es and members, minimu m bar clear an ce is 60 to 200 mm a nd t he

steel cont ent is roughly 100 t o 200 kg/m3. Therefore a self-compactability level of Rank 2 is selected

as a st anda rd for such structur es and members. Where the minimum bar clear ance is less tha n 60

mm or t he s teel content is more th an 350 kg/m3

, the self-compactabili ty level must be ra ised toRank 1.The cover depth an d bar clear ance should meet th e minimu m r equiremen ts specified in the

J SCE Sta nda rd Specificat ion. Where th e minimum bar clear an ce is more tha n 200 mm or less tha n

100 kg/m3 in te rm s of st eel conten t, th e self-compa ctabili ty level can be lower ed t o Rank 3. It

should be noted tha t concrete of a h ig h er se lf -compa cta bility ra nk is genera lly capa ble of

self-compacting u nder conditions corr esponding t o lower ra nks.

2 . 3 O t h e r p e r f or m a n c e s

Per form an ces of Self-Compa cting Concret e oth er t ha n self-compa ctability shall be established in

accorda nce with t he J SCE St an dar d Specificat ion.

[Commentary]In order t o sat isfy the perform an ce requirement s of th e stru cture an d constr uction r equirement s, it

is n ecessa ry t o select other performa nces t ha n t he self-compa ctability specific to Self-Compa cting

Concrete an d establish adequa te criteria for t hem. Since th ese perform an ces ar e similar t o norma l

concrete, they ar e required t o be in a ccorda nce with the J SCE St an dar d Specificat ion.

It is gener ally requir ed to esta blish the placeability for fresh concret e, stren gth a nd du ra bility for

ha rd ened concrete. The pla ceabili ty of fres h concret e is a capa bili ty requir ed of concret e from

immediately after i ts pr oduction t hr ough t he end of the placement. Concrete h aving t he required

placeability can be filled into forms uniformly and densely without causing segregation to

const ru ct a s t ru ctu re of th e required dimensions with th e required accur acy un der th e planed

constru ction conditions. The performa nces requir ed of ha rd ened concret e include st ren gth a nd

dura bility with which it can demonstra te t he r equired performa nce for the r equired period.



C h a p t e r 3 M a t e r i a l s

3 . 1 G e n e r a l

(1) Mat eria ls for s elf-compact ing concret e sha ll be of confT1rm ed qua lity.

(2) When ma ter ials for wh ich n o qua lity specificat ions a re pr ovided in J IS or J SCE St an dar ds ar e

to be used, shal l be confirmed t hat the mat erials sat is fy the qua l ity requirement s for h ar dened

concrete as well as th e self-compa cta bility requiremen ts.

[Commentary]

(1) Th e us e of suit able mat eria ls, ha ving th e required per form an ce, is necessar y for pr oducing

self-compa cting concret e. Mater ials specified in t he J SCE St an dar d specification can be judged a s

those whose qualities ha ve been confT1rm ed. Wheth er a ma terial is su itable can be judged by test s

or field experience.

(2) The self-compa ctability of mat eria ls not covered by th e J SCE St an da rd Sp ecification or of those

th at will be newly developed m ay be confT1rmed by t he veri f icat ion met hods provided in t h is

Recommendat ion. In th is case a s wel l , i t should be confirmed t ha t su ch concret e sat is f ies t h e

quality requirement s for har dened concrete specified in th e J SCE St anda rd Specificat ion.

Amongst th e ma ter ials not covered by JIS or t he J SCE St an dar d Specificat ion, th e following ar e

examp les of mat eria ls for s elf-compactin g concrete for which su fficient field experien ce has been

acquired:

a) Belite-rich port land cemen t

This is a type of portla nd cemen t developed for concret e proport ioned t o ha ve a high binder cont ent

Low-hea t portlan d cement specified in J IS R 5210 is included in t his t ype. The belite (dicalcium

silicate) cont ent of belite-rich port land cement is 40% to 70%, which is h igher t ha n m oderat e-heat

port land cement . This type of cement exhibits high deform ability a nd str ength development at a

low wat er-binder r at io, and is also cha ra cter ized by a lower hydra tion exoth erm th an convent iona lport land cement. For th is reason, it is used wher e high stren gth a nd/or low heat a re r equired.

b) Bina ry/terna ry system low-heat cement

This is a t ype of cement ma de of norm al or moderat e-heat port land cement mixed with ground

granu la ted blas t - fu rnace s lag an d /or f ly as h . Th is i s used wh ere des i red t ha t the hydra t ion

exother m be reduced without reducing the powder conten t.

c) Limest one powder

Limest one powder is l imest one consist ing prim ar ily of CaCO 3 (calcite) pulverized to a specific

sur face area by Blaine of 2500 to 8000 cm 2 /g. It can be regar ded inert , though m ar gina lly active,

and is used where des i red tha t the hydra t ion exoth erm a nd /or s t rength be redu ced wi thou t

redu cing the powder cont ent . For i ts qu alit ies, refer to the Qua lity Specificat ion for Limest onePowder for Concrete (draft) published by the J apa n Concrete I nstitute.

d) Viscosity a gent

Viscosity agent s ar e classified into two types: th ose used sim ply to impa rt segregat ion r esista nce to

fresh concrete a nd t hose used both for impa rt ing segregation resista nce and cur bing the effects of

fluctu at ing qua lit ies of th e m at erials. Glycol type a nd wat er-soluble a mide t ype liquid viscosity

agent s ar e beginn ing to be used in place of conventional powder types, such a s th e cellulose type,

acrylic type, polysaccha ride polymers, biopolymers an d in orga nic viscosity a gents.



C h a p t e r 4 P r op or t i o n in g

4 . 1 G e n e r a l

The mixtur e proport ions of self-compacting concret e sha ll be esta blished to sat isfy the per form an ce

requirement s provided in Cha pter 2.

[Commentary]

Self-compacting concrete is a concrete in which two normally incompatible properties of

deform ability an d segregat ion r esista nce are both r ealized to achieve self-compa ctability by such

meas ur es as t o increase th e powder cont ent an d/or u se of a viscosity agent. For t his rea son, a wide

variety of for mu las a r e poss ible for self-compa cting concrete sat isfying the self-compactability

requ irements as wel l as per form an ce requ i remen ts for ha rdened concre te , such a s dur ab i l ity

requ ired from environmen ta l conditions.

Concretes are therefore proportioned by selecting an adequate combination of materials in

consideration of the restricting conditions at production plants and economical efficiency including

their availability and tra nsporta tion cost.

It s hould be n ote d t ha t, in this Recommenda tion, the per form an ce items of self-compactin g

concrete, other than the self-compactability, are required to conform to the JSCE Standard

Specification [Construction].

Self-compactability is classified into three ranks corresponding to structural conditions of

structures. When proportioning self-compacting concrete, the self-compactability level is

determ ined from th e structural conditions of th e str uctur e to which t he concrete is applied, and

concrete is proport ioned t o att ain th is level.

The proport ioning meth ods, to atta in Self-compa cta bili ty of Rank 2 ea sily, are i l lust ra ted in th e

Man ua l for mixtur e proport ioning. These methods wer e for mu la te d on th e bas is of t he f ield

experience of using self-compa cting concret e up t o now with limited r an ges of mat eria ls. Therefore,when using mat erials other tha n t hose specified in th e Manua l, the m ixtu re proport ions must be

established separately so as to pass the performance verification provided in this

Recommendaition.

4 . 2 P r op or t i on i n g

When p roport ion ing self-compacting concret e, an appr opria te t ype of self-compa cting concret e sha ll

be selected. The ma terials an d their cont ents sh al l then be determ ined so th at the es ta bl ished

perform ance r equirements can be sat isfied.

[Commentary]

Self-compa cting concr ete m us t be pr oport ioned to achieve fil ling int o ever y comer of for ms t oensur e the performa nce of the stru ctur e. To th is end, it m ust be proport ioned to at ta in th e required

self-compacta bility imm ediat ely before being placed into forms in consider at ion of th e str uctu ra l

conditions, the construction conditions including the method and duration of transportation,

pla cing met hod and curing m ethod.

Self-compacting concrete is generally proportioned in a sequence as shown in Fig.4. 1. No

limita tions a re pu t on t he t echn ique of proport ioning, provided the r esulting concrete sa tisfies th e

perform an ce requirements.

The pr oportioning condition exam inat ion pr ocess in th e now cha rt is a pr ocess in which th e ta rget

perform ance requiremen ts a re es ta bl ished on the ba sis of the s t r uctur al condi t ions a nd, where

requir ed, const ru ction conditions of th e str uctur e.



The proportioning exam inat ion pr ocess in th e flow cha rt is a pr ocess in wh ich t ent at ive mixtu re

proportions (initial proportions) are calculated. Generally speaking, a suitable type of

self-compacting concrete is selected from am ongst t h e powder t ype, viscosit y age n t typ e and

combination t ype, based on t he per form an ce requiremen ts for t he concrete, production limita tions

an d economical efficiency. The ma teria ls are then selected, an d th eir cont ents ar e determ ined so

that the self-compactabil ity a nd per for m a nce of ha r den ed concrete can be at ta ined. Wherea s

var ious classificat ion system s a r e pos si bl e for self-compacting concrete, t his Re commen da tion

class ify it roughly into thr ee cat egories: the powder t ype, viscosity agent type a nd combina tion type,

as ment ioned in Chapters 1 a nd2.

Fig.4.1 Flow Cha rt of Mixtur e Pr oport ioning

In t he pr oport ioning confirmat ion Pr ocess , the tent at ively determ ined in i t ial proport ions a r e

checked if th ey satisfy th e perform an ce requir ement s. Unsat isfactory proportions ar e modified.

Trial mixtur es should, as a r ule, be produced to confT1rm t he qua lit ies of fresh, ha rden ing and

ha rden ed concret e. The self-compa ctability of fresh concret e ma y be conf1rm ed by the "test m eth od

for passa bility th rough spaces using a filling t ester ” described in Chap ter 5. Where t he ver ificat ionis possible by labora tory test s, th is confirm at ion process r epresent s t he verificat ion process. Where

test s usin g actua l equipmen t or full-scale models ar e to be condu cted, the verificat ion is carr ied out

after this process. This series of processes to determine t he ma ter ials and t heir cont ents is r eferr ed

to as pr oportioning.

4 . 3 F or m f or e x p r e s s i n g m i x t u r e p r o p or t i on s

The form for expr essing specified mixtu re pr oport ions s ha ll be gener ally as sh own in Table 4. 1.



Table 4. 1 Form for express ing mixtur e proport ioning

Notes 1 ) When more th an one m ater ia l of the sam e k ind i s used , each sha l l be ind ica t ed in a

separat e box.

2) The dosage of an a ir-entr aining and high -range water-redu cing admixtur e shall be expressed in

kg/m3 an d sha ll be included in the u nit wat er content .

3) Th e dosa ge of o ther chemical adm ixtur es sh am be expressed in ml/m3 or g/m3 an d s h a l l be

indicated un diluted an d u ndissolved.

4) The viscosity agen t cont ent sha ll be expres sed in kg/m3.

[Commentary]

The specified mixtur e proport ions sh all be expressed a s th e cont ent of each m at erial in t erm s of

mass per cubic meter of concret e . I t sh ould be noted t ha t t he wa ter -powder r at io by volume is

indicated in addition to t he wa te r -binder ratio, a s th e volum e of powder st r ongly a ffect s th e

deform ability a nd segregation r esistan ce of self-compacting concrete.

It is desira ble tha t t he form s include th e type of th e str uctur e, type of self-compacting concrete,

design s tr ength , age at which the design stren gth is assu red, type of cemen t, type and ph ysical

properties of minera l admixtures, type an d physical pr opert ies of coar se an d fine a ggregat es an d

type of chem ical adm ixtures. It is also desira ble th at i t includes th e str uctur al conditions of the

str uctur e, such as reinforcement condit ions, as well as th e constr uction condit ions, such as t he

transportation time, construction methods and seasonal conditions. The inclusion of the slump flow,

flow tim e to 500 mm an d funn el efflux time is recomm ended. These ar e useful for t he cont rol of

self-compactability.

C h a p t e r 5 P e r f or m a n c e ve r i f ica t i o n

5 . 1 G e n e r a l

(1) The proportioned self-compa cting concrete sh all be verified by a su ita ble meth od in r egar d to

the a tta inment of the esta blished performa nce.

(2) When t he a tt ain men t of th e esta blished perform an ce of th e proport ioned concret e is not verified,

the materials, m ixture proportions an d/or const ru ction condit ions shall be modi fied , a n d th e

resu lting concret e sh all be su bject to reverificat ion.

[Commentary]

(1) It is necessar y to verify th at th e concret e designed in a ccorda nce with Cha pter 2 possesses th e

designed per form an ce. This chapt er specifies th e met hods of such verification. The perform an ce

requirement s of concrete consist of various item s. All of th ese item s sh ould a s a ru le be verified, to

the extent t ha t t hey affect t he performa nce or constr uct ion plan of the s t r ucture. However, the

performance requirements for performance items are differently weighted depending on the

structur e a nd const ru ction conditions. In a ddition, the verification of one item can overlap th at of

an oth er. For this rea son, th e items an d meth ods of verification should be adequa tely selected.

The es ta bl ishm ent of non-tes t veri ficat ion methods is expected in t he futu re, s uch as physical

estima tion and n um erical simu lation. At pr esent, however, verificat ion by testing a nd inferrin gfrom field experience are m ore ra tional a nd r eliable in most cases. The met hods of verificat ion



should, th erefore, be selected su ita bly from a mong these.

(2) When the ch ecking for verification ha s r evealed t hat the concrete does not sat isfy th e

established perform an ce requirem ents , the mat erials should be reselected an d the concrete should

be reproportioned for r ever ification. If t h e concr et e ca nn ot be ra tiona lly pr oport ioned by th is

procedure, it may be necessary to review the construction conditions and, where required,

str uctur al conditions.

5 .2 Ver i f ica t ion o f se l f -compa ctab i l i ty

(1) The self-compa ctability of fresh concret e sh all be ver ified us ing full-scale m odels h aving sim ilar

stru ctur al an d constr uctional conditions simulat ing the a ctua l stru ctur e or members.

(2) Where test methods with established correspondence with the actual structural and

const ru ctiona l conditions a re a vailable, concret e ma y be verified by such test met hods.

(3) Where sta nda rd const ruction m ethods ar e to be a pplied, concrete m ay be verified by passability

test s using a filling test er with a n adequ at e obsta cle settin g accordin g to th e str uctu ra l conditions.

(4) In t he ca se of self-compa cting concret e with Ra nk 2 self-compa ctability, the concret e ma y be

verified by passability tests u sing a filling tester with obstacle R2.

[Commentary]

(1) Verificat ion of self-compa ctability of fresh concrete is import an t for ensu r ing th e per form an ce of

str uctur es. The verificat ion sh ould be carr ied out by prepar ing full-scale form s of th e str uctur e or

mem bers or model form s repr esent ing th e port ions wh ere t he placing is consider ed most difficult,

placing the proportioned concrete in them according to the assumed construction plan and

confirmin g t he sta te of filling of th e concret e.

(2) Where t he test met hods for the specific str uctu ra l and const ru ction condit ions h ave alrea dy

been established on th e ba sis of f ield exper ience, th e use of such me th ods for veri f icat ion is

permitted. In regard to the fresh concrete performance, the verification should include

confirmat ion t ha t t he concret e can be pumped a s planed, th at it does not segregate du ring placing

an d flowing lat era lly an d filled into every comer of forms wit hout clogging ar ound r einforcemen t inth e stru cture. It is difficult t o confirm th ese items by a single test m eth od. Therefore, th ese ar e

genera lly judged by combinat ions of multiple test meth ods, such a s pa ssability tests using a filling

tester combined with slump flow test s or funn el tests.

(3) an d (4) Wher e th e concret e is placed und er st an dar d constr uction conditions, verification by th e

test s specified in J SCE St an dar ds is permitted. These a re pa ssability tests u sing a fil ling tester,

shown in Fig.5.1, a ccordin g t o the Rank of th e concr et e est ab lish ed in considerat ion of t h e

structural conditions. This h as been concluded from field exper ience acquir ed to dat e (see th e

reference). The standar d constr uction conditions referred t o here ar e assu med t o be a m aximum

drop height of not more th an 5 m a nd m aximum later al flow distan ce of not m ore t ha n 8 t o 15 m. A

flow slope of 1/l0 to 1/30 an d pu mpin g th rough 4- or 5-inch pipes n ot m ore th an 300 m in lengt h are

also considered standard.



Fig.5. 1 Sha pes an d Dimensions of Appara tu s for

Self-Compa ctability Test

When Ra nk 2 self-compa cta bility is required, the concrete is judged as sat isfying th e requirem ent,

if i ts fi ll ing heigh t is not less t ha n 300 mm by a f il l ing tes ter with obsta cle m. When Ra nk 1

self-compactability is required, the concrete is judged as satisfying the requirement, if its filling

height is not less th an 300 mm usin g obsta cle R1. The met hods for concret e of Ran k 3 include

test ing by a filling tester without a ny obsta cle.

In t he cas e wher e th e self-compa cta bi li ty is veri fied at a s t age oth er th an imm ediately before

placing t he concrete in forms, it should be confT1rmed t ha t t he chan ges in concrete qu alities after

th e point of test a re su fficient ly small. The qua lities of fresh concret e ten d to cha nge over t ime, an d

their propert ies also chan ge depending on t he type an d size of mixers. Their qua lit ies may also

cha nge after pum ping. For this rea son, these changes should be thoroughly grasped when test s ar e

conducted a t a n earlier s tage th an sh ould be. However, wher e such cha nges can be gra sped

th oroughly by th e met hods indicated in the Placement Man ua l or from field exper ience, th e

concret e ma y be verified by laborat ory tests.

Fig.5.2 Timing of test for verificat ion of Self-compa ctability



5 . 3 Ver i fi ca t i on o f o t h e r p e r form an ce it em s

Fu lfil lmen t of performa nce items oth er t ha n self-compa ctabili ty shall be verified in accorda nce

with th e J SCE Sta ndar d Specificat ion.

[Commentary]

Where perform an ce items other th an self-compactabili ty are esta blished and ar e required to be

verified, th ey should be verified at appr opriat e t imes by suita ble methods. Though th e time a nd

met hod for such veri ficat ion a re n ot specif ied in th e cur rent J SCE Sta ndar d Specificat ion, the

perform an ce of concrete can be confirmed, e.g., by the met hods given in 13.5 an d 13.9 in t he J SCE

Sta nda rd Specificat ion [Const ru ction]. This can be regar ded as a su bstit ut e for verification.

C h a p t e r 6 P r od u c t ion a n d C on t r ol

6 . 1 G e n e r a l

Production plans for self-compacting concrete shall be adequately formulated to obtain the

required qualities and the production shall be adequately controlled according to the plan.

[Commentary]

Self-compa cting concrete differs from norma l concrete in t he ma ter ials a nd mixtur e pr oport ions,

and particularly in the properties at fresh state. Therefore, the processes of producing

self-compacting concrete, such as batching and mixing, should be properly carried out in

well-equipped plan ts so th at th e requ ired qu alit ies of fresh concrete can be obtain ed. Also, such

production sh ould be a dequat ely cont rolled so tha t th e expected cha ra cter istics of self-compa cting

concret e can be realized. Gener al items for pr oduction should be in accord an ce with t he J SCE

Sta nda rd Specificat ion [Const ru ction].

6 . 2 P ro d u c t i on

(1) The su rface moisture ra tio shall be adequat ely measur ed, and the surface moistu re corr ection

shall be ensur ed.(2) Self-compacting concrete shall be adequately mixed using equipment with the required

efficiency so tha t t he r equired qu alities of concret e can be obtained.

(3) Self-compa ct ing concrete pr oduced at p lant s sh al l be tes t ed t o conf1rm t ha t i t sa t is f ies t he

established performa nce requiremen ts for fresh concrete. If it does not sa tisfy the r equirem ent s,

th e mixtu re pr oportions sh all be modified.

[Commentary]

(1) Self-compa cting concret e is genera lly more suscep tible to fluctu at ion of un it wat er cont ent th an

norma l concrete. For th is reason, it is necessary t o cont rol fluctuat ion of the su rface moistu re r at io

of aggregate, particularly fine a ggre gat e, in order to pr oduce self -compacting concrete ha ving

stable qualit ies. In order t o redu ce th e advers e effects of such fluctua tion, the su rface moistur e

should be mea sur ed by an adequa te met hod and i ts corr ect ion should be made accur at ely an dpromptly.

(2) Self-compa cting concret e is char acter ized by the low yield value a nd h igh plast ic viscosity when

compa red with n orma l concrete. It should, th erefore, be mixed usin g a mixer with high m ixing

efficiency and t he order of charging ma ter ials, batch size and mixing time should be adequa tely

establ ished a ccording t o tes t resul ts or f ield experience, in order to obtain concrete h aving th e

required qualities.

(3) The pr operties of fresh self-compa cting concrete produced using t he pla nt to be used for actu al

construction may frequently differ from those of self-compacting concrete proportioned in advance

in labora tories . This resul ts from different mixin g eff iciency of the mixer. In s u ch a cas e t he

proportions a re n orma lly corrected by a djustin g th e dosage of an air -entra ining. and high -rangewater-reducing admixture. See th e Man ua l for Pr oduct ion an d Pla cemen t for det ai ls of su ch



adjustment.

6 . 3 Q u a l i t y c on t r o l d u r i n g p r o d u c t i on

(1) The de form ability, segrega tion r esista nce a nd self-compacta bility of self-compa cting concrete

sha ll be cont rolled as t he qua lity cont rol durin g production.

(2) Deform abilit y ma y be contr olled by slum p flow test ing. Resist an ce to segregation may b e

cont rolled by the flow time t o 500 mm or efflux tim e th rough fun nels. Self-compa cta bility may be

cont rolled by tests for passa bility th rough spa ces usin g a filling test er.

[Commentary]

Self-Compacta bility should be cont rolled in qu alit y cont rol tes tin g of self-compa cting concrete in

addition t o tests for norma l concrete, in order to exercise su fficient cont rol over its chara cteristics.

The percent age or a mount of bleeding wat er is an in dex to sta tic segrega tion resist an ce of concret e,

an d is useful for such qua lity cont rol. The power consu mpt ion of the m ixer dur ing mixing can also

be u sed for such cont rol.

Other qual i ty contr ol i tems and tes t m ethods are pr ovided in the J SCE Sta nda rd Specificat ion

[Construction]. These should be observed accordingly.

C h a p t e r 7 C on s t r u c t i on a n d con t r o l

7 . 1 G e n e r a l

In order t o at ta in the specified quality of th e entire str uctur e, an a dequat e const ru ction plan sha ll

be formulated for self-compacting concrete and adequate control shall be exercised so that

const ru ction can be car ried out a ccording to the pla n.

[Commentary]

There are a number of points of note specific to self-compacting concrete in the concreting work

from product ion to curing after p lacing. In order t o ensu re th e requir ed qual i t y of th e ent i re

stru ctur e, including the function, stren gth a nd dur ability, an adequa te const ru ction plan should beformulated in careful consideration of t he se point s. Also, cont r ol sh ould be exercised so th a t

concreting is carried out smoothly in accordance with the plan. General matters regarding

concreting should be carried out in accordance with the JSCE Standard Specification

[Construction].

7 . 2 C o n v e y in g , p l a c in g , f in i sh i n g , cu r i n g a n d j oi n t s

(1) The type an d nu mber of concret e pum ps a nd dia met er a nd length of pipelines sha ll be selected

with t horough consider at ion to the tes t resu lts an d field experience.

(2) The placing r at e of self-compa cting concrete should be est ablished a dequa tely according t o the

mixture proportions, geometry of members and reinforcement conditions on the basis of test

results a nd field experience.

(3) The ma ximum permissible drop height a nd flow dista nce should be established in a dvan ce forself-compacting concret e with d ue consider at ion t o th e mixtu re pr oport ions, st ru ctur al condit ions

an d const ru ctional conditions.

(4) The sta nda rd pum ping conditions sh all be as follows:

Diam et er an d l en g t h o f t h e p i p e l in e : 4 o r 5 i n ch es a n d n o t m o re t h an 3 0 0 m , r e s p ec t i v e l y;

ma ximum free drop height of concrete: around 5 m or less; and m aximum latera l flow dista nce: 8 to

15 m or less.

(5) Measu res t o preven t su rface drying should be ta ken for self-compacting concret e unt il finis hin g

operation is performed, and care should be exercised not to miss the time for taking such

measures.

(6) Tr ea tm en t a t constr uction joint s of self-compactin g concrete m ay be simp lified, provided it is

confirm ed tha t su ch joints h ave at ta ined the r equired perform an ce.



[Commentary]

When self-compacting concret e is conveyed by pumping, an in crease in t he pu mpin g rat e ten ds to

lead to a grea ter pressur e loss th an normal concrete. Also, pumping generally tends to reduce the

slump flow of self-compa cting concrete. Ther efore, t he t ype an d nu mber of pumps as well as t he

diameter and length of pipelines m ust be selected with thorough considerat ion to test results and

field experience. Pu mping t hr ough 4- or 5-inch pipes not m ore t ha n 300 m in length should be the

stan dar d pumping conditions.

Excessively quick placing of self-compact ing concret e can en tr ap air or cause d efective m1in g in

certain structures. It is, therefore, necessary to establish the placing rate adequately according to

the mixtur e proport ions, geometry of mem bers a nd r einforcemen t condit ions ba sed on test r esults

an d field experience. Wh en pla cing in t o closed spaces, it is importa nt to select th e m ixtur e

proport ions so as t o reduce the slope of th e flowing concret e an d select th e placing rat e adequ at ely.

Though self-compacting concrete is proportioned to provide high deformability and resistance to

segregation,segregat ion can occur w hen it is dr opped or flowed for an excessively long dista nce.

The p ermiss ible drop height an d f low dis ta nce should , therefore, be es ta bl ished in advan ce in

considera tion of the mixtur e proport ions a nd st ru ctura l and const ru ction conditions. The st an dar d

maximum free drop h eight an d ma ximum lat era l flow distan ce should be around 5 m or less and 8

to l5 m or less, respectively.

Finish ing work is difficult t o perform on self-compa cting concret e, due to its high viscosity a nd

lit t le am ount of bleeding wat er. It is , th erefore, necessa ry to ta ke meas ur es to prevent su rface

drying until t he t ime of finishing, an d care sh ould be exercised not to miss th e time t o take su ch

measures.

The small amount of bleeding water of self-compacting concrete forms less laitance on the

const ru ction joint su rfaces tha n norm al concrete. For th is reason, the r equired performa nce of th e

joint s ur faces can often be att ained even with simplified trea tm ent of th e surfaces.

7 . 3 Fo rm wo rk (1) The latera l pressur e of self-compact ing concret e act ing on t he formwork sh al l as a ru le be

designed as liquid pressure.

(2) When placing self-compacting concrete into closed spaces, vent holes shall be provided at

appr opriat e positions in th e top form s.

(3) For st ru ctures wh ose aest hetic appea ra nce will be jeopar dized by surface voids, car e sha ll be

exercised when selecting the ma ter ials of shea th ing and t ype of form rem overs.

[Commentary]

(1) The lat era l pressu re of self-compa cting concret e placed in th e form s acts s imilar ly to l iquid

pressu re on th e forms, due to its h igh deform ability. In addit ion, th e genera lly longer set ting t ime

than normal concrete tends to reta in the high lateral pressu re for a longer t ime. Therefore, th e

latera l pressur e of self-compacting concrete on th e form work should as a ru le be designed as liquidpressure.

(2) Air in closed spaces should be a llowed t o escape out of the form s a s concret e is filled in t hem . To

th is end, vent holes should be provided at a ppropria te positions in consider at ion of th e pla cing

meth od an d sha pes an d dimensions of th e port ions t o. be placed.

(3) Self-compa cting concret e can leave ma ny voids on t he form ed sur faces. For st ru ctur es on which

such voids will dam age th eir aest hetic appear an ce, the ma ter ials for sheat hing an d type of form

rem overs sh ould be selected with car e, as t hese can affect th e sta te of air -voids being left on form ed

sur faces. Light t appin g on th e sur faces of form s ma y be requ ired in cert ain cases.

7 . 4 Q u a l i t y c on t r o l d u r i n g c on s t r u c t i on(1) Qua lity cont rol dur ing const ru ction sh all as a ru le be exercised at t he t ime of concret e placing.



(2) Quality cont rol testin g on self-compa cting concret e ma y be condu cted at th e point of unloading

ta king account of the qua lity cha nges dur ing conveying from t he point of un loading t o the point of

placing.

(3) It is recomm ended th at th e deforma bility, segregation resista nce and self-compa cta bility shall

be cont rolled for qua lity cont rol of self-compacting concre te.

[Commentary]

7.4 Though t he qu ality cont rol of self-compa cting concret e dur ing const ru ction s hould a s a ru le be

exercised at th e tim e of concret e placing, testin g at th e point of placing is often difficult . For th is

rea son, qua lity contr ol tests a re norm ally conducted at t he point of un loading ta king into account

the qua lity cha nges dur ing conveyance from t he u nloading point to the placing point .

The deform ability, segregat ion r esista nce an d self-compactability should be cont rolled for qua lity

control of fresh self-compacting concrete. Whether the concrete attains the required

self-compa ctability a t t he point of unloading can also be judged by placing a passa bility a ppar at us

between th e agitat or t ru ck and t he mobile pump, with which the pa ssability of the whole tr uckload

can be aut omat ically tested.

Other qua lity contr ol it ems for fresh concrete include the air cont ent , tem pera tu re, unit mass an d

chloride ion content. These and other items and test methods of quality control during construction

are provided in the JSCE Standard Specification [Construction]. These should be observed

accordingly.

C h a p t e r 8 I n s p e c t i on

8 . 1 G e n e r a l

Inspection sha ll be conducted on pr oduced and placed concrete a t a n a ppropriate time t o check if it

satisfies the established performance requirements.

[Commentary]

Even if th e perform an ce of concrete sat isfies the est ablished requirement s at the verificat ion st age,

it normally undergoes changes, due to fluctuation in material qualities, fluctuation during

production an d quality cha nges durin g tra nsport at ion/conveyance. It is , therefore, necessar y to

conduct inspection a t a n a ppropriate t ime by a suita ble method to see if the produced and placed

concrete sa tisfies the esta blished perform an ce requir ement s.

8 . 2 In s p ec t i o n o f s e l f - co m p a c t a b il t y

(l) The self-compacta bility of concre te sh all be inspected before pla cing.

(2) The inspect ion for self-comp acta bi l i ty sha l l be car r ied out at leas t once for ea ch 50 m3 or

fraction th ereof of concrete by passa bility test s u sing a filling t ester .

(3) If all possible factors for qua lity fluctu at ion of concret e ar e iden tified an d if su ch factors can beinspected by a t est m ethod with est ablished correspondence with passa bili ty tests u sing a fill ing

tester, su ch t ests ma y substitut e for inspection t ests.

(4) Concret e rejected in th e inspection sh all be tr eat ed adequ ately. The causes for su ch rejects sh all

be identified to impr ove subsequen t pr oduction.

[Commentary]

(1) The per form an ce of concret e produced an d tr an sported for actu al const ru ction can differ from

th at of designed concret e. It is, th erefore, import an t t o condu ct inspection before placing, even if

the concrete ha s been verified at t he design sta ge. It is par ticularly importa nt to examine before

placing th at produced an d t ra nsported concrete a t t ains the es tabl ished Self-compactabi li ty for

ensuring reliabili ty of the str ucture. Since the chan ges in t he t emperatu re a nd t ran sporta tion t ime

dur ing the constr uct ion can al ter t he self-compa ctabi l i ty from t he designed level , i t ha s to beconfirmed by a suit able met hod by th e time th e placing begins.



The inspection is generally car ried out at th e point of unloading after pr oduction/tran sport at ion. In

th is case, i t sh ould be confirm ed th at th e chan ges in th e self-compa ctabili ty due to conveyance

within th e site, such as pum ping after un loading, are sufficiently small. The t ime a fter pr oduction

an d before shipping may be specified for in spection, if it is a lso confirm ed th at th e tr an sporta tion

after production causes only ma rgina l cha nges in t he self-compactability.

(2) Self-compactabi l ity may be inspected by passabi lity t es ts with a Bl1ing te s ter used at th e

verification stage. The obstacle conditions corresponding to the established self-compactability

ra nk should be used for t esting. An inspection frequen cy of at least once for ea ch 50 m3 or fra ction

thereof of concrete was adopted referring to the frequency of inspection specified for

superplasticized concrete.

(3) A s imple al terna t ive tes t met hod ma y be appl ied in p lace of th e inspect ion, if the possible

factors for qu ality fluctu at ion of concret e dur ing production ar e ident ified an d if such a Simple t est

meth od is esta blished, wher eby corr espondence can be esta blished with th e criteria for rejection in

the inspection by passability tests using a filling tester. Where the measurements during

production can be reviewed by prin ted r ecords a nd t he factors for possible qua lity fluctua tion ar e

limited to the fluctua tion in moistu re cont ent an d high-ran ge water -reducing agent, th e evalua tion

can be m ad e by a combinat ion of slum p flow an d flow tim e to 500 mm or fun nel efflu x time. In th is

cas e, it is necessary to establish judgmen t criter ia corr esponding to rejection by pas sability test s

using a filling test er.

When self-compacting concrete is applied to general reinforced concrete structures (Rank 2

self-compa ctabili ty), 100% test ing with a pa ssa bili ty test er m ay be a pplied for in spection. One

hundred percent testing with a passability tester can automatically judge if a Rank 2

self-compactability concrete possesses the required self-compactability, having established

correspondence with passa bility testin g with a filling test er. The whole tru ckload can be inspected

by ins ta l ling th i s t es te r be tween a n a g ita to r t r uck con ta in ing concre te an d a mobile pum p t o

receive it. This type of test er could also be u sed for concret e of oth er self-compactability ra nks byan adequ at e sett ing of the obsta cle conditions. Refer t o th e Manu al for P roduction an d Placement

for detailed descriptions of 100% test methods.

(4) When a n inspection ha s r ejected a concrete for low deform ability, th e concret e m ay be add ed

with a h igh-range water-reducing agent at a dosage in a predeterm ined ran ge for r einspect ion.

When rejected for segr egation, the concrete m ust not be used. In a ny case, the cau ses for r ejection

must be identified for adequat e an d prompt remedial measu res t o improve subsequent pr oduction.

8 . 3 I n s p e ct i on of ot h e r p e r f or m a n ce i t e m s

Inspection of performance items other than self-compactability shall be conducted in accordance

with th e J SCE Sta ndar d Specificat ion.

[Commentary]

Where r equirement s h ave been est ablished for perform an ce items other th an self-compactability,

for which inspection is r equired, it should be conducted a t a n a ppropriate t ime by suitable met hods.

The t ime an d meth ods for the inspect ion shou ld be in accorda nce wi th th e JSCE St an dar d

Specification.

Recommendation for Self-Compacting Concrete

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