EXPERIMENTAL RESEARCHES CONCERNING REHABILITATION … · Debonding of CFRP vertical strip due to...

PRESENTATIONPRESENTATION:: PhD Eng.PhD Eng. Catalin Catalin BADEABADEA,,““Politehnica”University of TimisoaraPolitehnica”University of Timisoara

EXPERIMENTAL RESEARCHES CONCERNING EXPERIMENTAL RESEARCHES CONCERNING REHABILITATION METHODS REHABILITATION METHODS

AND THE USE OF NEW BULDING MATERIALS AND THE USE OF NEW BULDING MATERIALS USING INDUSTRIAL WASTEUSING INDUSTRIAL WASTE

ERASMUS PROGRAMME June 2007ERASMUS PROGRAMME June 2007

Into this lecture are presented the following Into this lecture are presented the following experimental researches:experimental researches:

C.C.Buildings rehabilitation methods Buildings rehabilitation methods

E.E.New bulding materials using industrial wasteNew bulding materials using industrial waste

A.A. Buildings rehabilitation methods contents:Buildings rehabilitation methods contents:

A1. Experimental researchesA1. Experimental researches

A2. Rehabilitation of existing structures:A2. Rehabilitation of existing structures:

A2.1. The Timisoreana BreweryA2.1. The Timisoreana Brewery

A2.2. Apartament House affected by an explosionA2.2. Apartament House affected by an explosion

A2.3. Ortodox ChurchesA2.3. Ortodox Churches

A2.4. Old Malting Tower of Timisoreana BreweryA2.4. Old Malting Tower of Timisoreana Brewery

A2.5. Masonry Buildings affected by recent eartquackeA2.5. Masonry Buildings affected by recent eartquacke

A1. A1. EXPERIMENTAL EXPERIMENTAL RESEARCHES RESEARCHES

Experimental programmeExperimental programme on RC structures on RC structures

Experimental RC frameExperimental RC frame + CFRP strengthening+ CFRP strengthening

ExperimentalExperimentalRC frameRC frame

φ

φ

φ

φ

φ

φ φ

φ

φφ

φ

φ

φ

Concrete C16/20Plain steel OB37

φ φ

φ

φ

φ

φ

φ φ

RC frame RC frame columns columns strengthened strengthened withwith CFRP: CFRP:

• longitudinal strips, SIKA Carbodur, anchored in foundations and at longitudinal strips, SIKA Carbodur, anchored in foundations and at the top jointsthe top joints::

• transversal confinement with SIKA wrap at both ends of the transversal confinement with SIKA wrap at both ends of the columns. columns.

Mechanical anchorageMechanical anchorage

Glued Glued anchorageanchorage

Wrap Wrap anchorageanchorage

BehaviourBehaviour and and failure offailure of CFRP CFRP strengtheningstrengthening::

Debonding of CFRP Debonding of CFRP vertical strip due to tensile vertical strip due to tensile

stressesstresses

Debonding of CFRP Debonding of CFRP vertical strip due to vertical strip due to compression stressescompression stresses

Pull-out of concrete and Pull-out of concrete and CFRP from foundationCFRP from foundation

BehaviourBehaviour and failure of and failure of RC frames strengthened with RC frames strengthened with CFRPCFRP::

• FRAME 1FRAME 1::-- ddebonding of CFRPebonding of CFRP vertical strip from glued anchoragevertical strip from glued anchorage due to tensile due to tensile

stresses at top joints;stresses at top joints;-- pull-out of CFRPpull-out of CFRP and concrete from foundation. and concrete from foundation.

• FRAME 2FRAME 2::-- ddebonding of CFRP vertical strip from wrap anchorageebonding of CFRP vertical strip from wrap anchorage due to tensile due to tensile

stresses at top joints;stresses at top joints;-- debonding of CFRP vertical stripdebonding of CFRP vertical strip due to compression stresses; due to compression stresses;-- pull-out of CFRPpull-out of CFRP and concrete from foundation. and concrete from foundation.

• FRAME 3FRAME 3::-- pull-out of CFRPpull-out of CFRP and concrete from foundation; and concrete from foundation;-- no debonding of vertical strips from mechanical anchorageno debonding of vertical strips from mechanical anchorage at top joints. at top joints.

Ratio edstrengthen-non

edstrengthenfor

Model State of Structure

Horizontal Load Level “S” (daN)

Top Maximum Displacement (mm) Loads Displacements

Non-strengthened 1600 * 5.44

1600 * 3.87

Frame 1

CFRP strengthened

4000 ** 30.20

- −

*71.0

1600 * 4.60 Non-strengthened

3600 ** 15.27

1600 * 4.50

Frame 2

CFRP strengthened

3800 ** 30.70

1.06 **00.2

*98.0

Non-strengthened 1600 * 7.60

1600 * 5.50

Frame 3

CFRP strengthened

3600 ** 29.80

- −

*72.0

Notes: * yielding stage of reinforcement ** ultimate stage

Experimental Experimental resultsresults

Top-displacement values for RC non-strengthened and CFRP strengthened Top-displacement values for RC non-strengthened and CFRP strengthened framesframes

0

400

8001200

1600

2000

2400

28003200

3600

4000

0 4 8 12 16 20 24 28 32

δ [mm]

S [daN]Frame 1: RC

Frame 2: RC

Frame 3: RC

Frame 1: RC+CFRP

Frame 2: RC+CFRP

Frame 3: RC+CFRP

Conclusions:Conclusions:

The experimental tests performed on RC framed The experimental tests performed on RC framed structure emphasized some main aspects of the CFRP structure emphasized some main aspects of the CFRP strengthening system:strengthening system:

- - the slight increase of bearing capacity and the decrease the slight increase of bearing capacity and the decrease ofof top-displacement up to the service stage;top-displacement up to the service stage;

-- peeling-off failure of CFRP strips at the top joint due to peeling-off failure of CFRP strips at the top joint due to debondingdebonding without a proper anchorage;without a proper anchorage;

-- debonding of CFRP strips in the compressed zone in debonding of CFRP strips in the compressed zone in case of proper transversal reinforcement absence.case of proper transversal reinforcement absence.

A2. A2. Rehabilitation of existing structuresRehabilitation of existing structures

A2.1 A2.1 The Timisoreana The Timisoreana BBreweryrewery

a) a) R.C. framed structureR.C. framed structure

COLUMN

b

b Carbodur S1012

60x60

230C 60x50 Sikawrap HEX

25

75

12

S1012 Carbodur

230C 60x50 Sikawrap HEX

b-b

1.20

Car

bodu

r S

1012

75

75

Sik

awra

p H

EX

230C

60x

50

1.20

Sikawrap HEX 230C 60x50

1.20

S1012 Carbodur Carbodur

S1012

Carbodur S1012

S1012 Carbodur

1.00

a-a a a

+3.45 1.40

70

75

+4.35

BE

AM

230C

60x

50

Sik

awra

p H

EX

(a)

(b)

COLUMN

BEAM

BE

AM

COLUMN

• CFRP strengthening solutionCFRP strengthening solution

• Strengthening performed for:Strengthening performed for:- one column (weakness of- one column (weakness of longitudinal reinforcement) longitudinal reinforcement)- many beams (weakness of- many beams (weakness of shear reinforcement, shear reinforcement, corrosion of many stirrups) corrosion of many stirrups)

CFRP strengthening of columnsCFRP strengthening of columns CFRP strengthening of beamsCFRP strengthening of beams

A2.1 A2.1 The Timisoreana The Timisoreana BBreweryreweryb) b) RC silosRC silos

Discharge Discharge funnelfunnel

Charging platformCharging platform

Main damagesMain damages::

• corrosion of the columns and beams steel reinforcement of corrosion of the columns and beams steel reinforcement of discharge funnel and silos cells due to humidity;discharge funnel and silos cells due to humidity;

• wide open cracks in RC walls of the charging platform wide open cracks in RC walls of the charging platform due due the temperature action on the frame-wall coupled systemthe temperature action on the frame-wall coupled system..

Reinforcement corrosion Reinforcement corrosion of discharge funnel of discharge funnel supporting columnssupporting columns

Silos cells reinforcement corrosionSilos cells reinforcement corrosionCracks in RC walls of Cracks in RC walls of charging platformcharging platform

Silos circular cellsSilos circular cells

Modern strengthening solutionModern strengthening solution::

CFRP strips as near surface mounted CFRP strips as near surface mounted reinforcement.reinforcement.

The SikaWRAP HEX-230C strips The SikaWRAP HEX-230C strips were placed on the most stressed zone were placed on the most stressed zone (+3.20…+13.20 m), outside of cells.(+3.20…+13.20 m), outside of cells.

This solution seemed to be more This solution seemed to be more advantageous than the near surface advantageous than the near surface mounted reinforcement of CFRP mounted reinforcement of CFRP rods.rods.

135

60

20

990

cm

SikaWRAP HEX-230C

730 cm

±0.00

RC cells - outside face

150

160

15

0 15

0 15

0

150

135

20 1

35 2

0 1

35 2

0 1

35 2

0 1

35 2

0

350

320

Charging platform cracked wallsCharging platform cracked wallsModern strengthening solution – CFRPModern strengthening solution – CFRP::

10 4

18 36 cm

10

100

Floor over cells

Roof floor

5 cm

5

cm

300

cm

Sik

a C

arbo

Dur

Lam

elle

S10

12

4 10

5 10 5

4 10 4 10

Circ

ular

RC

wal

l

Circ

ular

RC

wal

l

Sik

a C

arbo

Dur

Lam

elle

S51

2

The solution has the advantage of The solution has the advantage of easy technology, short period of easy technology, short period of refurbishment and small refurbishment and small rehabilitation cost. rehabilitation cost.

On the other hand, the buckling On the other hand, the buckling phenomenon of the phenomenon of the SikaCARBODUR strips is not SikaCARBODUR strips is not possible to show up.possible to show up.

A2.2 A2.2 Apartment house affected by explosionApartment house affected by explosion

Building descriptionBuilding description

• built in 1976built in 1976

• 5 stories with 100 bed-sitters5 stories with 100 bed-sitters

• in plane dimensions 43.55x14.75 m in plane dimensions 43.55x14.75 m and a sub-basement and fire story and a sub-basement and fire story of 2.72 m highof 2.72 m high

• vertical structure: longitudinal vertical structure: longitudinal and transversal reinforced (over and transversal reinforced (over the borders) concrete walls of the borders) concrete walls of 30 cm width for concrete facades 30 cm width for concrete facades and 15 cm of the interior wallsand 15 cm of the interior walls

• horizontal structure of 14 cm horizontal structure of 14 cm width precast reinforced concrete width precast reinforced concrete floorsfloors

• new reinforced concrete floors, with the same geometry and reinforcement new reinforced concrete floors, with the same geometry and reinforcement characteristics as for the existing members, at levels 3, 4 and 5, total 5 elementscharacteristics as for the existing members, at levels 3, 4 and 5, total 5 elements

• new reinforced concrete walls at levels 4 an 5 which represent 4 transversal walls new reinforced concrete walls at levels 4 an 5 which represent 4 transversal walls (with the same width as of the corresponding walls with new shirts) and 4 (with the same width as of the corresponding walls with new shirts) and 4 longitudinal – lateral wallslongitudinal – lateral walls

Rehabilitation solutionsRehabilitation solutions::

30 15 1.40 15 1.50 15 1.40 15 304.604.60

60x20column

20x30beam

+5.44

+8.16

+10.8814

2.58

1414

2.58

welded mesh fabric wire

welded mesh fabric wire

20x30beam

20x30beam

20x30beam

beam20x30

beam20x30

column60x20

column30x20

30x20column

• rehabilitation rehabilitation of the cracked of the cracked elements with elements with CFRP (Sika wrap)CFRP (Sika wrap)for 10 transversalfor 10 transversalwalls and 12 floorswalls and 12 floors

A2.3 A2.3 Orthodox churchesOrthodox churches

Main damagesMain damages: : aarches and vaults presented damages due to the foundationsrches and vaults presented damages due to the foundations settlement as well as earthquake actionssettlement as well as earthquake actions

Moldova Noua ChurchMoldova Noua Church• RC structural elements RC structural elements

(columns 30x60 cm and (columns 30x60 cm and beams / straps 30x60 cm), beams / straps 30x60 cm), which were connected with which were connected with the existing structure by the existing structure by steel anchors;steel anchors;

• CFRP wraps for the CFRP wraps for the arches. arches.

Strengthening solutionsStrengthening solutions::

S 1 60 x 30 cm

C 60 x 30 cmS 2 30 x 60 cm

Oradea ChurchOradea Church• near-surface-mounted-near-surface-mounted-

reinforcement technology reinforcement technology with High Adherence Steel with High Adherence Steel Bar PC52 and Brutt Bar PC52 and Brutt Helical System BHS.Helical System BHS.

PC52BHS

The system was applied The system was applied outside the walls at upper and outside the walls at upper and bottom part of the windowsbottom part of the windows..

A2.4 Old Malting A2.4 Old Malting Tower Tower of Timisoreana Breweryof Timisoreana Brewery

Building descriptionBuilding description

• old malting building, erected old malting building, erected between 1857-1876 at the between 1857-1876 at the “Timisoreana” Brewery“Timisoreana” Brewery

• a five storeys masonry structure a five storeys masonry structure and a tower and a tower

• walls of 140 – 50 cm thickness;walls of 140 – 50 cm thickness;

• inter-storey floors - brick masonry inter-storey floors - brick masonry vaults supported by steel profiles;vaults supported by steel profiles;

• a tower, of about 14 m height and a tower, of about 14 m height and 2.80 m diameter, supported by an 2.80 m diameter, supported by an interior dome.interior dome.

Main damagesMain damages::

• vertical cracks in the tower vertical cracks in the tower masonry structure;masonry structure;

• corrosion of steel members: corrosion of steel members: horizontal circular rings for horizontal circular rings for confining the tower; profiles confining the tower; profiles for supporting the floor for supporting the floor masonry vaults. masonry vaults.

Rehabilitation solutionRehabilitation solution::• for general stability of masonry tower: vertical reinforcement bars (4 x 3Φ20) for general stability of masonry tower: vertical reinforcement bars (4 x 3Φ20)

embedded at the upper side of the tower in a RC beam and welded on steel profiles embedded at the upper side of the tower in a RC beam and welded on steel profiles HE 240 M placed in the dome, at the tower base; vertical CFRP wrap (4 x 2 strips HE 240 M placed in the dome, at the tower base; vertical CFRP wrap (4 x 2 strips of 20 cm width) on the entire tower heightof 20 cm width) on the entire tower height;;

20

R=1.30

R=1

.50

3φ20

R=1.80

20

RC circular

verticalCFRP strips

20

Tower masonry wall

20

Conectors φ16

5φ16

+29,3220

3φ20

25

70

20

40

verticalCFRP strips

Tower masonry wall

• in masonry structure, at zones with stresses greater that masonry tensile strength, in masonry structure, at zones with stresses greater that masonry tensile strength, were placed horizontal RC straps: at the tower – dome crossing; at the base of were placed horizontal RC straps: at the tower – dome crossing; at the base of dome that supports the tower; at the level of steel profiles HE 240 M for its dome that supports the tower; at the level of steel profiles HE 240 M for its embedding into vertical masonry structure;embedding into vertical masonry structure;

• on the vertical cracked tower: corroded circular steel rings for confining the tower on the vertical cracked tower: corroded circular steel rings for confining the tower on outside face were replaced by horizontal CFRP stripson outside face were replaced by horizontal CFRP strips..

HE 240 ML=3.75m

HE

240

M

L=

9.40

m

φ

φ

φ φ

HE

240

M

L=

9.40

m

HE 240 ML=3.75m

HE 240 ML=3.75m

HE 240 ML=3.75m HE 240 M

L=2.60m

S1-

20x3

0cm

S1-

20x3

0cm

HE 240 ML=2.60m

8

Masonry dome

+15,65

8

8

8

8

Masonry tower

8CFRP strips

+29,32

30

A2.5 A2.5 Masonry buildings affected by a recent earthquakeMasonry buildings affected by a recent earthquake

Main damages due to earthquakeMain damages due to earthquake

• fracture of some precast strips of the floor over the sub-basefracture of some precast strips of the floor over the sub-base

• important damages of the longitudinal walls at the first floorimportant damages of the longitudinal walls at the first floor

• a lot of cracks on the longitudinal walls at 2a lot of cracks on the longitudinal walls at 2ndnd to 5 to 5thth floors floors

• inclined cracks on the interior longitudinal wallinclined cracks on the interior longitudinal wall

• vertical cracks on thevertical cracks on thetransversal walls near the jointtransversal walls near the jointwith longitudinal wallswith longitudinal walls

• horizontal cracks on thehorizontal cracks on thetransversal walls, at the first level,transversal walls, at the first level,under the floorunder the floor

Rehabilitation solutionRehabilitation solution::• general strengthening of the perimeter walls with RC framed structures consisting general strengthening of the perimeter walls with RC framed structures consisting

of columns (20x40 cm) and beams (20x40 cm), which were connected with the of columns (20x40 cm) and beams (20x40 cm), which were connected with the existing structure by steel anchors;existing structure by steel anchors;

• new reinforced concrete slab (monolith, 6 cm thickness) over the existing precast new reinforced concrete slab (monolith, 6 cm thickness) over the existing precast strip at the first floor;strip at the first floor;

1.40

2.05

3.302.30 3.00

3.40

3.30

8080

2.05

15

3.302.302.3028 3.30

3.00

3.40

1528

1.73

151.

755

1.20

2.00

5.08

2.30

Beam 20x40 cmColumn 20x40 cm

Strengthened elements:

40 2.30 40 2.06 40 3.30 40 3.26 40 1.20

28 28 28 28

CFRP Sika wrap

28 28 28 28 28

2824

90 2.10

90 2.10

• rehabilitation of the interior longitudinal wall using CFRP (Sika wrap)rehabilitation of the interior longitudinal wall using CFRP (Sika wrap)

B. New building materials using industrial waste:B. New building materials using industrial waste:

B1. Building materials realised with B1. Building materials realised with fly ash fly ash and microsilicaand microsilica

B2. Building materials realised with B2. Building materials realised with ultra fine fly ash ultra fine fly ash and and

microsilicamicrosilica

INTRODUCTIONINTRODUCTION ( (FLY ASHFLY ASH))

• FLY ASH FLY ASH is a waste product created when coal is burned to produce electric is a waste product created when coal is burned to produce electric

power. In the past, this fine, powder-like waste material was simply hauled to a power. In the past, this fine, powder-like waste material was simply hauled to a

disposal site near the electric power plant that produced it and dumped. disposal site near the electric power plant that produced it and dumped.

• In addition to the value of recycling, what was once a useless waste product, In addition to the value of recycling, what was once a useless waste product,

there are other advantages to using fly ash: it does not cost any more per load to there are other advantages to using fly ash: it does not cost any more per load to

use than sand; it does not have to be hauled a long distance even costs less than use than sand; it does not have to be hauled a long distance even costs less than

traditional fill materials; using fly ash instead of cement in concrete production traditional fill materials; using fly ash instead of cement in concrete production

reduces carbon dioxide emissions.reduces carbon dioxide emissions.

• The fly ash produced from the burning of pulverized coal in a coal-fired boiler is a The fly ash produced from the burning of pulverized coal in a coal-fired boiler is a

fine-grained, powdery particulate material that is carried off in the flue gas and fine-grained, powdery particulate material that is carried off in the flue gas and

usually collected from the flue gas by means of electrostatic precipitators, bag usually collected from the flue gas by means of electrostatic precipitators, bag

houses or mechanical collection devices such as cyclones.houses or mechanical collection devices such as cyclones.

INTRODUCTIONINTRODUCTION ( (MICROMICROSILICA SILICA ))

• MICROMICROSILICASILICA is a byproduct of producing silicon metal or ferrosilicon alloys. One is a byproduct of producing silicon metal or ferrosilicon alloys. One

of the most beneficial uses for silica fume is in concrete. Because of its chemical of the most beneficial uses for silica fume is in concrete. Because of its chemical

and physical properties, it is a very reactive pozzolan. Concrete containing and physical properties, it is a very reactive pozzolan. Concrete containing

micromicrosilica can have very high strength and can be very durable.silica can have very high strength and can be very durable.

• The use of industrial wastes like fly ash and The use of industrial wastes like fly ash and micromicrosilicasilica represent a positive represent a positive

position regarding the conservation and the protection environment.position regarding the conservation and the protection environment.

The experimental researches regarding the use of considerable quantity of fly ash The experimental researches regarding the use of considerable quantity of fly ash

((from power plantfrom power plant)) and microsilica and microsilica to obtain building materials to obtain building materials like heavy mortars like heavy mortars

or compacted lightweight concretes or compacted lightweight concretes are presentedare presented..

In this paper the author’s experimental researches regarding building materials In this paper the author’s experimental researches regarding building materials

like heavy mortars or compacted lightweight concretes obtained by using like heavy mortars or compacted lightweight concretes obtained by using

ultra fine fly ash and microsilica.ultra fine fly ash and microsilica.

The experimental researches were realized on mixtures with the following composition:The experimental researches were realized on mixtures with the following composition:

- water = - water = 2020%;%;

- dry material = 8- dry material = 800%.%.

The dry material was proposed with the next percent combination:The dry material was proposed with the next percent combination:

-sand 0-3 mm sort = sand 0-3 mm sort = 4040%;%;

-blended binders = blended binders = 660%.0%.

To establishing of blended binders was used the next model:To establishing of blended binders was used the next model:

%%Σ Σ blended binders = %blended binders = %Σ Σ (classic binders + F + M)(classic binders + F + M)

where: classic binders = cement (C) and lime (L);where: classic binders = cement (C) and lime (L);

F = ultra fine fly ash from power plant;F = ultra fine fly ash from power plant;

M = microsilica.M = microsilica.

B1. Building materials realised with B1. Building materials realised with fly ash fly ash and microsilica and microsilica

The composition mixture with industrial recycling waste (fly ash and microsilica)

No. BatchWater

[%]Lime[%]

Cement[%]

Silica fume[%]

Fly ash[%]

Sand[%]

1.Series 1L10 C10

22.4 4.7 4.7 - 37.2 31

2.Series 2L10 C10 M5

22.4 4.7 4.7 2.3 34.9 31


22.4 4.7 4.7 4.7 32.5 31


22.4 4.7 9.4 2.3 30.2 31


22.4 7.0 7.0 4.7 27.9 31


22.4 4.7 9.4 4.7 27.8 31

Physical and mechanical properties

Rcρa,

[ kN×mkg ]

No. Batch

Apparent densityρa, [kg/m3]

Tensile strengthfcf, [N/mm2]

Compression strength

fc, [N/mm2]

7 days 28 days 7 days 28 days 7 days 28 days

1.Series 1L10 C10

1726 1718 0.70 2.62 4.14 11.62 6.76


1735 1724 1.61 3.75 5.83 15.04 8.72


1747 1736 1.61 4.03 6.10 16.60 9.56


1774 1743 2.23 4.21 8.70 20.18 11.58


1754 1754 2.22 4.45 7.66 21.51 12.34


1784 1758 2.64 4.68 10.04 23.79 13.53

Σ(L+C+M)

2.62

3.754.03

4.214.45

4.68

0,70

2.64

2.222.23

1.61 1.61

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

5

20% Series 1 L10C10

25% Series 2

L10C10M5

30% Series 3

L10C10M10

35% Series 4

L10C20M5

40% Series 5

L15C15M10

40% Series 6

L10C20M10 BATCH

fcf [N/mm2]

7 days

28 days

Legend:

Tensile strength

Σ (L+C+M)

11.62

15.04

20.1821.51

23.79

10.04

4.14

5.83

7.668.70

6.10

16.60

0

3

6

9

12

15

18

21

24

27

20%

Series 1

L10C10

25%

Series 2

L10C10M5

30%

Series 3

L10C10M10

35%

Series 4

L10C20M5

40%

Series 5

L15C15M10

40%

Series 6

L10C20M10 BATCH

fc

7 days

28 days

Legend:

Compressive strength

[N/mm]2

6.76

8.729.56

11.5612.34

13.53

8.29

11.11

3.5

0

2

4

6

8

10

12

14

16

20% Series 1 L10C10

25% Series 2

L10C10M5

30% Series 3

L10C10M10

35% Series 4

L10C20M5

40% Series 5

L15C15M10

40% Series 6

L10C20M10

Mortar M100

ConcretC16/20

Ceramicbrick 50

mark BATCH

Rc/ρa

[kN∗m/kg]

%Σ(L+C+M)

fc/ρa

CONCLUSIONSCONCLUSIONS TO B1 TO B1

The main conclusions from these tests are presented below.The main conclusions from these tests are presented below.

• The apparent density at 28 days for different batches, have a value between 1718 and The apparent density at 28 days for different batches, have a value between 1718 and

1758 kg/m1758 kg/m33 which framed the materials in medium heavy mortars category or which framed the materials in medium heavy mortars category or

lightweight concretes. lightweight concretes.

• At 28 days the tensile strength At 28 days the tensile strength ffcfcf has values between 2.62 N/mm has values between 2.62 N/mm22 and and

4.68 N/mm4.68 N/mm22 anand the compressive strength d the compressive strength ffcc between 11.62 N/mm between 11.62 N/mm22 and 23.79 N/mm and 23.79 N/mm22

like M 100 mortar and C 16/20 lightweight concrete class.like M 100 mortar and C 16/20 lightweight concrete class.

• The technical efficiency coefficient show as that the new material with recyclable The technical efficiency coefficient show as that the new material with recyclable

industrial industrial waste have the same technical efficiencywaste have the same technical efficiency like classic bulding materials like classic bulding materials..

• The biggest increased values were obtained for increasing percent of cement (20%) The biggest increased values were obtained for increasing percent of cement (20%)

and and micromicrosilica (10%).silica (10%).


• The adding of 10% of The adding of 10% of micromicrosilicasilica (series 3 L10 C10 M10) by comparison with series (series 3 L10 C10 M10) by comparison with series

1 L10 C10 (control sample) without silica fume produced an increase of 1 L10 C10 (control sample) without silica fume produced an increase of

1.41 N/mm1.41 N/mm22 for tensile strength for tensile strength ffcfcf that means 53,8% and an increase of 4.98 N/mm that means 53,8% and an increase of 4.98 N/mm22

for compressive strength for compressive strength ffcc that means 42.9%. that means 42.9%.

• Increasing the percent of Increasing the percent of micromicrosilica from 5% (series 2 L10 C10 M5) to 10% (series silica from 5% (series 2 L10 C10 M5) to 10% (series

3 L10 C10 M10) let to an increase of the tensile strength with maximum 11.2% and 3 L10 C10 M10) let to an increase of the tensile strength with maximum 11.2% and

compressive strength with maximum 29.6%.compressive strength with maximum 29.6%.

• For a comparison between series 1 L10 C10 (control sample) and series 6 For a comparison between series 1 L10 C10 (control sample) and series 6

L10 C20 M10 which has with more 10% cement and 10% L10 C20 M10 which has with more 10% cement and 10% micromicrosilicasilica was recorded was recorded

the biggest increased value for the tensile strength (with 2.08 N/mmthe biggest increased value for the tensile strength (with 2.08 N/mm22 = 78.6%) and = 78.6%) and

the compressive strength (with 12.17 N/mmthe compressive strength (with 12.17 N/mm22 = 104.7%). = 104.7%).

The experimental researches were realized on mixtures with the following composition:The experimental researches were realized on mixtures with the following composition:

- water = 15%;- water = 15%;

- dry material = 85%.- dry material = 85%.

The dry material was proposed with the next percent combination:The dry material was proposed with the next percent combination:

- sand 0-3 mm sort = 25%;- sand 0-3 mm sort = 25%;

- sand 3-7 mm sort = 25%;- sand 3-7 mm sort = 25%;

- blended binders = 50%.- blended binders = 50%.

To establishing of blended binders was used the next model:To establishing of blended binders was used the next model:

%%Σ Σ blended binders = %blended binders = %Σ Σ (classic binders + (classic binders + UUF + M)F + M)

where: classic binders = cement (C) and lime (L);where: classic binders = cement (C) and lime (L);

UUF = ultra fine fly ash from power plant;F = ultra fine fly ash from power plant;

M = microsilica.M = microsilica.

B2. Building materials realised with B2. Building materials realised with ultra fine fly ash ultra fine fly ash and and microsilica microsilica

BatchWater

[%]Lime[%]

Cement[%]

Microsilica[%]

Ultra fine

fly ash[%]

Sand 0-3 mm

[%]

Sand 3-7 mm

[%]

Series 1 L10 C10

16.1 4.2 4.2 0 33.6 16.8 25.1

Series 2 L10 C10 M10

16.1 4.2 4.2 4.2 29.4 16.8 25.1


16.1 4.2 8.4 4.2 25.2 16.8 25.1


16.1 4.2 12.6 4.2 21.0 16.8 25.1

Note: was added 0.5% additive (polycarboxylatether) from blended binders quantities

The composition mixtures with industrial recycling waste (ultra fine fly ash and microsilica)

Rcρa,

[ kN×mkg ]

Physical and mechanical properties of hardened mixtures at 7 and 28 days

Batch

Apparent densityρa, [kg/m3]

Tensile strengthfcf, [N/mm2]

Compression strength

fc, [N/mm2]

7 days28

days7 days

28 days

7 days28

days

Series 1 L10 C10

1944 1931 2.23 3.75 9.74 20.81 10.78


1986 1965 2.65 4.08 10.40 21.31 10.84


2016 1986 3.16 4.80 12.14 26.53 13.36


2029 1992 3.80 5.39 16.53 31.56 15.84

The apparent density

2016 2029198619441992198619651931

0

300

600

900

1200

1500

1800

2100

2400

20% Series 1 L10C10

30% Series 2

L10C10M10

40% Series 3

L10C20M10

50% Series 4

L10C30M10 BATCH

ρ a [kg/m3]

7 days

28 days

Legend:

Σ(L+C+M)

The tensile strength [N/mm

2.23

2.65

3.16

3.83.754.08

4.8

5.39

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

5

5.5

6

20% Series 1 L10C10

30% Series 2

L10C10M10

40% Series 3

L10C20M10

50% Series 4

L10C30M10 BATCH

fcf [N/mm2]

7 days

28 days

Legend:

Σ (L+C+M )

The compression strength

[N/mm]

9.74 10.412.14

16.53

20.81 21.31

26.53

31.56

0

4

8

12

16

20

24

28

32

20% Series 1 L10C10

30% Series 2

L10C10M10

40% Series 3

L10C20M10

50% Series 4

L10C30M10 BATCH

fc [N/mm2]

7 days

28 days

Legend:

Σ(L+C+M)

10.78 10.84

13.36

15.84

8.29

11.11

13.2

0

2

4

6

8

10

12

14

16

18

20% Series1 L10C10

30% Series 2

L10C10M10

40% Series 3

L10C20M10

50% Series 4

L10C30M10

Mortar M100

ConcreteC16/20

ConcreteC20/25

BATCH

Rc/ρa

[kN∗m/kg

%Σ(L+C+M)

The technical efficiency coefficient

-1.80

-1.60

-1.40

-1.20

-1.00

-0.80

-0.60

-0.40

-0.20

0.00

0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34Time [days]

ε, [mm/m]

Series 1 L10C10

Series 2 L10C10M10

Series 3 L10C20M10

Series 4 L10C30M10

Legend:

The shrinkage


•• The apparent density at 28 days old for different batches, has a value between The apparent density at 28 days old for different batches, has a value between

1931 and 1992 kg/m1931 and 1992 kg/m33 which framed the materials in heavy mortars category or compacted which framed the materials in heavy mortars category or compacted

lightweight concretes. lightweight concretes.

•• At 28 days the mechanical resistances have big values: tensile strength At 28 days the mechanical resistances have big values: tensile strength

ffcfcf between 3.75 N/mm between 3.75 N/mm22 and 5.39 N/mm and 5.39 N/mm22, the compressive strength , the compressive strength ffcc between between

20.81 N/mm20.81 N/mm22 and 31.56 N/mm and 31.56 N/mm22 like M 100 mortar and C 12/15 - C 20/25 compacted like M 100 mortar and C 12/15 - C 20/25 compacted

lightweight concrete class.lightweight concrete class.

•• The technical efficiency coefficient show as that the new materials (with The technical efficiency coefficient show as that the new materials (with

recyclable waste) have the same technical efficiency like classical building materials.recyclable waste) have the same technical efficiency like classical building materials.

•• The biggest increased strength values were obtained for increasing percent of The biggest increased strength values were obtained for increasing percent of

cement (30%) and microsilica (10%) for series 4 L10C30M10.cement (30%) and microsilica (10%) for series 4 L10C30M10.

•• The limit of the water absobtion in function of mass for materials researched is The limit of the water absobtion in function of mass for materials researched is

under lightweight concrete limit and near to ceramic brick limit.under lightweight concrete limit and near to ceramic brick limit.

•• The shrinkage has the values between -1.02 mm/m and -1.53 mm/m which The shrinkage has the values between -1.02 mm/m and -1.53 mm/m which

are greater than ordinary building materials.are greater than ordinary building materials.

ADVANTAGESADVANTAGES

Two important advantages are obtained by using Two important advantages are obtained by using fly ash fly ash to produce building to produce building

materials:materials:

- the use an industrial waste (fly ash) which occupy large area for store - the use an industrial waste (fly ash) which occupy large area for store

resulting a good impact on environment;resulting a good impact on environment;

- obtaining building materials with low cost (ordinary characteristics involve - obtaining building materials with low cost (ordinary characteristics involve

more less ordinary binders) or with perceptible economy (over 25% economy more less ordinary binders) or with perceptible economy (over 25% economy

by comparison with materials with superior characteristics).by comparison with materials with superior characteristics).

Bulding material for pavment with ultra fine fly ashBulding material for pavment with ultra fine fly ash

REFERENCESREFERENCES (selection) (selection)

5. Nanni A., Tumialan J. G. – Fibre-Reinforced Composites for Strengthening of Masonry Structures, SEI Journal of IABSE, Vol. 13, No. 4, 2003

7. Bob C., Dan S. – The Increase of Building Performance to Seismic Actions, Bulletin AGIR, 5(4) (in Romanian), 2000

9. Bob C., Dan S. – Analysis, Redesign and Rehabilitation of Reinforced Concrete Framed Structures in Seismic Regions, fib Symposium: Concrete Structures in Seismic Regions, Athens, 2003

11. Bob C. – Evaluation and Rehabilitation of a Building Affected by a Gas Explosion, Progress in Structural Engineering and Materials, Vol. 6, No. 3, 2004

12. Töljsten B. – FRP Strengthening of Concrete Structures, New Inventions and Applications, Vol. 6, No. 3, 2004

14. Stoian V. et. all – Composite Materials for Construction, Ed. Politehnica, Timisoara, (in Romanian), 2004

REFERENCESREFERENCES (selection) (selection)

5. Bob C., Bob L., Florea V., Gruin A. – New Techniques for Rehabilitation of Masonry Structures, IABSE Symposium: Structures and Extreme Events, Lisbon, 2005

7. Bob, C., Dan, S., Gruin, A., Dan, Z., - Rehabilitation of Reinforced Concrete Structures in Seismic Zones by Using CFRP, Proceedings of the fib Symposium Keep Concrete Attractive, Budapest, 2005

9. Badea C., Bob C. - Experimental research on some new building materials realised with fly ash, Symposium Composite materials, elements and structures for constructions, Timisoara Academic Days, Timisoara, 2005

11. Badea C., Bob C., Building materials with fly ash and phospho-gypsum, International Symposium Interdisciplinary Universitaria SIMPRO 2005, Petrosani, 2005

13. Badea C., Bob C. - Use of fly ash to obtain building materials, The VI International Symposium Young People and Multidisciplinary Research, Timisoara, 2006

15. Civil Engineering Department researches, “Politehnica” University of Timisoara

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