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Journal of Engineering and Development, Vol. 17, No.1, Mar. 2013, ISSN 1813‐ 7822

Structural Behavior Of Self-Compacting Concrete Reinforced

T-Beams

Prof. Dr. Mohammed M. Salman Asst. Prof. Dr. Mohammed M. Rasheed Yahya S. Khudhair

AL-Mustansiriya University AL-Mustansiriya University AL-Mustansiriya University

College of engineering College of engineering College of engineering

Civil Engineering Dept. Civil Engineering Dept. Civil Engineering Dept.

[email protected] [email protected] [email protected]

Abstract The study is concerned with the structural behavior of (12) reinforced T-shaped cross-

section beams made of self-compacting concrete under flexural with two types of fibers

(polypropylene and steel fibers). Compression and tensile strengths, deflection, ductility and

cracking behavior are considered. Experimental results are compared with these evaluated

based on the (ACI 318 – 08). The variables studied are reinforcing ratio (%ρ) (between %4.4907

- %6.0434) using different sizes of reinforcing steel bars (Ф25mm, Ф20mm, Ф16mm, Ф12mm,

Ф6mm, Ф4mm, and Ф6mm wire mesh), in addition to two fibers, [polypropylene (RHEO-

FIBERS®) and steel fibers (FIBERFORCE®) at a rate of [(1kg/m3) & (0.5%)], respectively. The

tested T-Beams were categorized into three groups, each group includes (4) T-Beams of different

steel ratios (ρ %). In Group (G1), polypropylene fibers were used. In Group (G2), steel fibers

were used. The reference group (G3) is with the same reinforcement ratios as in the previous

two groups.

It was concluded that using polypropylene fibers (RHEO-FIBERS®)in addition to (1kg/m3)

in self-compacting concrete (SCC) improves the cracking control, ductility by (Δμd = 0.5846 –

4.0514). However, fibers have minor effect on the deflection behavior of T-Beams. On the other

hand, when steel fibers type (FIBERFORCE® steel fibers) of a volume rate of (Vf = 0.5% of

concrete volume Vc) are used in combination with self-compacting concrete, affects the flexural

behavior of T-Beams (reducing deflection, increasing ultimate loads' by (11.02% - 16.80%) and

improving the ductility by (Δμd = 4.9232 – 12.1238), but it has a minor effect on reducing the

crack width. Keywords: Self-Compacting Concrete; T-Beam; Steel Fibers; Polypropylene Fibers; Superplasticizer;

Silica fume; Limestone Powder; Flexural Behavior; Cracking Behavior; Deflection; Ductility Factor.

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mailto:[email protected]




(T)السلوك اإلنشائي للعتبات الخرسانية الذاتية الرص ذات المقاطع بشكل حرف

يحيى صابر خضير محمد محمد رشيد .محمد مصلح سلمان االستاذ المساعد د.االستاذ د ة المستنصريةعالجام ة المستنصرية ع الجام ة المستنصرية عالجام

لية الھندسة كلية الھندسة ك كلية الھندسة قسم الھندسة المدنية نية قسم الھندسة المد قسم الھندسة المدنية

:الخالصة ) عتب١٢( بعدد (T)أن ھذا البحث يھدف ألى دراسة السلوك األنشائي للعتبات الخرسانية ذات المقاطع بشكل حرف

مج عملي شامل ، مع األخذ وأن دراسة ھذا البحث تتضمن برنا, ) ألياف البوليمر وألياف الحديد(والمسلحة بنوعين من األلياف على سلوك الخرسانة الذاتية الرص ) ألياف البوليبروبيلين وألياف الحديد(بنظر األعتبار تأثير أضافة ھذين النوعين من األلياف

وتحسين المطيلية ، باألضافة ألى نمط وعرض , ومقدار الھطول , ومقاومة الشد , مقاومة األنضغاط (كتأثيرھا مثال على ومقارنة النتائج المستحصلة عمليا مع النتائج المحسوبة تخمينيا ) الذي ممكن أن يظھر في الخرسانة الذاتية الرصالتشقق

المتغيرات التي تم . وكل ھذا تم دراسته خالل ھذا البحث العملي , )٢٠٠٨( لسنة (ACI 318طبقا للمدونة األمريكية المرقمة وذلك %) ٦.٠٤٣٤ - % ٤.٤٩٠٧( حيث تم أخذھا بنسب تتراوح مابين (%ρ)دراستھا خالل البحث ھي نسبة التسليح

٦شبكة بقطر , ملم ٤, ملم ٦, ملم ١٢, ملم ١٦, ملم ٢٠, ملم ٢٥(بأستخدام أقطار مختلفة من قضبان حديد التسليح ھي / كغم ١(ضافة مقداره بمعدل أ) ®RHEO-FIBER(باألضافة ألى ذلك أنه تم أستخدام ألياف البوليبروبيلين من نوع , ) ملمكنسبة حجمية من الحجم الكلي للخرسانة ) ٠.٥%( بنسبة أضافة مقدارھا (®FIBERFORCE)وألياف الحديد من نوع , ) ٣م

كل مجموعة أستخدم فيھا أربع نسب , تم توزيعھا على ثالث مجاميع (T)كل العتبات ذات المقاطع بشكل حرف . الذاتية الرص وھذه النسب تم تكرارھا على المجاميع الثالثة مع أستخدام ألياف البوليبروبيلين , لفة من حديد التسليح من التسليح بأقطار مخت

بينما تم أستخدام ألياف الحديد , في خلطة الخرسانة الذاتية الرص لعتبات المجموعة األولى (®RHEO-FIBERS)من نوعأما المجموعة الثالثة فقد تم , لعتبات المجموعة الثانية في خلطة الخرسانة الذاتية الرص (®FIBERFORCE)من النوع

. صبھا بدون أستخدام أي نوع من األلياف لكونھا المجموعة التي سوف يتم المقارنة معھا / كغم ١(وقد أظھرت النتائج العملية لھذا البحث أنه بأضافة ألياف البوليبروبيلين من النوع أعاله وبنسبة أضافة مقدارھا

مع الخرسانة الذاتية الرص تؤثر بدرجة كبيرة على تحسين السيطرة على التشققات التي يمكن أن تحصل للخرسانة وتعمل ) ٣م، بينما ]٤.٣٥١٥ ألى ٢.٠٣٥٦) = Δμd(التغير بالمطيلية [وكذلك تحسين عامل المطيلية بمقدار يتراوح مابين , على تقليلھا

لكن عندما يتم أستخدام ألياف الحديد من النوع . ول للعتبات الخرسنية الذاتية الرص قليال يكون تأثيرھا على تقليل مقادير الھط(FIBERFORCE®) تظھر تأثيرا كبيرا ) من الحجم الكلي للخرسانة الذاتية الرص%0.5( وبنسبة أضافة حجمية مقدارھا

ألى % ١١.٧٨(ي بمقادير عالية تتراوح مابين على تقليل مقادير الھطول وزيادة مقدار الحمل األقصى لفشل العتب الخرسانولكنھا , ]١٢.١٢٣٨ ألى ٤.٩٢٣٢) = Δμd(التغر بالمطيلية [مع تحسين عامل المطيلية بمقدار يتراوح مابين %) ١٨.٤٢

تكون ذات تأثير قليل على تقليل عرض التشققات التي تظھر على العتبات الخرسانية الذاتية الرص ذات المقاطع بشكل حرف (T).

؛ الملدنات المتفوقة؛ )البوليبروبيلين(؛ ألياف البوليمر د؛ ألياف الحدي(T)الخرسانة الذاتية الرص؛ العتب ذو المقطع بشكل :دالةالكلمات ال؛ مسحوق حجر النورة الكلسي؛ السلوك المرن؛ سلوك التشقق؛ الھطول؛ )مادة بوزوالنية ذات خواص أسمنتية(مسحوق السيليكا الفعال

. مل المطيليةعا

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1. General Self-compacting concrete (SCC) represents one of the most significant advances in concrete

technology. Inadequate homogeneity of the cast concrete due to poor compaction or segregation

may drastically lower the performance of nature concrete at site. (SCC) has been developed to

ensure adequate compaction and to facilitate placement of concrete in structures with congested

reinforcement and in restricted areas(1).

2. Scope & Objectives Experimental work includes a comparison between three groups of twelve T-Beams, each

group contains four T-Beams having the same Self-Compacting Concrete mix of the same strength

in the same group, but with different reinforcement ratios for the four beams in each group.

Polymeric or polypropylene fibers of (1kg/m3) ratio and steel fiber of (Vf= %0.5) were used in the

first and second groups respectively, while the third group was without reinforcing fibers.

Comparison is made between flexural behavior and cracking behavior of the elements in each

group.

3. Details of Test Beams The used dimensions of test beams are (1500mm) in overall length and (250mm) in total depth,

the effective width of flange is (330mm), the thickness of flange is (40mm), the clear width of web

is (180mm) and the web depth is (210mm) as illustrated in Figure (1).

286


Stirrup Ф12mm@40mm (c/c).

The whole beams are made of the same type of concrete, with no cold joints between its web and

flange, the type of loading during the test of T-beam samples is of two-point loading as illustrated

in Figure (2). So, the third clear span of loading is (430mm) and the distance from the face of beam

edge to the center of supports is (105mm), there is the same distance to the two beam sides. The

type of beam supporting is simply supported. Plate (1) shows the T-Beam setup for testing stage

with three dial gauges under its web.

210

430m430m

(c) Details of Shear Reinforcement (Stirrup)

Figure (1): Details of Flexural T-Beam.

.T-Beam Cross-section) b(

(a) Details of distributed Stirrup Bars along T-Beam shear span length with

concrete covers.

250mm

105 105

1500 mm

Cc = 20mm Cc =

20mm

20

10mm

)mm20 = (Cc Cc= (20mm)

Bent up

70 140mm

220m

m

330mm

180 mm

20mm (Cc)

4٠m

m

250m

m

20 20

287


288

Plate (1): The T-Beam set up with Three Dial Gauges.

Point Load Point Load

330 mm

Flange

40m

m 40m

m

250 mm

250m

m

Web

180 mm

430mm 430 mm 430 mm 105mm 105 mm

1500 mm

Fig e. ure (2): Application of Two-point Loading upon T-Beam flang


4. Materials Materials were selected according to a mix design method taking into account material grading

& properties. Satisfactory SCC is achieved by more strength requirements of the ingredients in

selecting suitable materials, and good quality control and proportioning.

4.1. Cement MASS BAZIAN SULAIMANIA Portland cement type (1) was used. It was tested according to

the Iraqi Standard Specifications (IQS) No. 5/1984(2) for the physical and chemical properties, as

shown in Tables (1) and (2), respectively.

Table (1): Physical Properties (Composition) of Cement

Physical Properties Test

Results

Iraqi Specifications

No.5/1984

Fineness using Blain air permeability apparatus(m2/kg) 381 > 230

Initial setting time using Vicat's instruments (hr:min.) 1:55 > 00:45

Final setting time using Vicat's instruments (hr:min.) 4:25 < 10:00

Safety (soundness) using autoclave method (%) 0.01 < 0.8

Compressive strength for cement paste cube (70.7mm) at :

(3days) in (N/mm2) or (MPa) 25.85 > 15

Compressive strength for cement paste cube (70.7mm) at :

(7days) in (N/mm2) or (MPa) 28.0 > 23

4.2. Fine Aggregate Al-Ukhaidher natural sand with fineness modulus of (2.69) was used it is of rounded particle

shape and smooth textures and of a maximum size of (4.75mm),therefore, requires less mixing

water in concrete and for this reason it is preferable in SCC. Grading and sulfate content are shown

in Table (3).Which satisfy the Iraqi Standard Specifications No.45 / 1984(3)– Zone No. (2).

4.3. Coarse Aggregate Crushed gravel of maximum size of (19mm) was used from Al-Niba'ee quarry region. Table

(4) shows the grading and percentage of sulfate content of the aggregate, which confirms to the

Iraqi Standard Specification No.45 / 1984(3) – size of grading (5-20) mm.

289


Table (2): Chemical Composition of Cement

Numbering Compound

Name

Compound

Chemical

Composition

% (weight)

Iraqi Standard

Specifications

No.5/1984

1 Silica SiO2 19.80 -------

2 Alumina Al2O3 5.11 -------

3 Iron Oxide Fe2O3 3.28 -------

4 Lime CaO 64.53 -------

5 Magnesia MgO 1.78 < 5

6 Sulfate SO3 2.55 < 2.8

7 Insoluble

Residue I.R. 1.06 < 1.5

8 Loss on ignition L.O.I 3.11 < 4

8.29 (From X.Ray

diffraction) 9

Tricalcium

aluminates C3A

7.9983 (From Bogue

equations)

-------

10 Lime saturation

factor L.S.F 0.98 0.66-1.02

11 C4AF 9.9712 ----------

12 Tricalcium

silicate C3S 65.86 ----------

Dicalcium

silicate C2S 7.16756 ---------- 13

290


Table (3): The Grading and Sulfate Content of Fine Aggregate (Sand)

Sieve Size Iraqi specification No. 45/1984 for

grading Zone(2) of % passing of

fine aggregate

Deviation

% Cumulative of

passing fine

aggregate In

(μm)

In

(mm)

No.

100 0 100 10000 10 1

90-100 0 94 4750 4.75 2

75-100 0 82 2360 2.36 3

55-90 0 69 1180 1.18 4

35-59 0 55 600 0.6 5

8-30 0 24 300 0.3 6

0-10 0 7 150 0.15 7

<5 ----- 4.1 75 0.075 8

------ ----- 0 Pan 9

< 5 0 Summation of deviations 10

< 0.5 % Sulfates Content = 0.069 11

Table (4): The Grading and Sulfate Content of Coarse Aggregate (Gravel).

Sieve Size Limit of Iraqi specification No.

45/1984 for grading size (5-20)mm of

% passing of coarse aggregate

Deviation

% Cumulative of

passing fine

aggregate In

(μm)

In

(mm)

No.

75000 75 1

100 0 100 37500 37.5 2

95-100 0 99 20000 20 3

14000 14 4

30-60 0 30 10000 10 5

0-10 0 3 5000 5 6

2360 2.36 7

< 3.0 ----- 0.0 75 0.075 8

------- ----- 0 Pan 9

0 0.00 Summation of deviations 10

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< 0.1 % Sulfates Content = 0.05 11

4.4. Limestone Powder Limestone powder has been used as filler for concrete production for many years. It has been

found to increase workability and early strength, as well as to reduce the required compaction

energy. The increased strength is found particularly when the powder is finer than the Portland

cement particles. The fine limestone powder (locally named as Al-Gubra) of Iraqi northern zone

with fineness (411 m2/kg) is used to avoid excessive heat generation, enhance fluidity and

cohesiveness, improve segregation resistance and increase the amount of fine powder in the mix

(cement and filler). According to EFNARC(٤), the fraction less than 0.125 mm was of most

benefit. Typical properties of lime stone powder (L.S.P) are listed in Table (5).

Table (5): The Typical Properties of Limestone Powder (L.S.P)

Physical property Range

Fineness by using Blain apparatus (m2/kg) 411

Chemical Composition % Content

So3 1.63

CaCo3 94.90

4.5. Mixing Water Ordinary tap water was used for both mixing and curing.

4.6. Superplasticizer The superplasticizer or High Range Water Reducing Admixture (HRWRA), used in this type of

concrete, is one of the high performance concrete superplasticizer based on modified

polycarboxylic ether. GLENIUM 51(5)is the superplasticizer which was used, it is free from

chlorides and complies with ASTM C494 Type A and F.

GLENIUM 51 is compatible with all Portland cements that meet recognized international

standards. It is differentiated from conventional superplasticizers in that it is based on a unique

carboxylic ether polymer with long lateral chains. This greatly improves cement dispersion.

GLENIUM 51 is available in 208 liter drums and in bulk tanks upon request. Table (6) illustrates

some important typical properties of GLENIUM 51 according to the requirements of BASF Middle

East Technical Products Guide. The normal dosage of GLENIUM 51 is between 0.5 and 1.6 liters

per 100 kg of cement (cementitious material). Dosages outside this range are permissible subject to

trial mixes. The maximum effect is achieved when the GLENIUM 51 is added after the addition of

50 to 70 % of the water. GLENIUM 51 must not be added to the dry materials, through mixing is

292


essential, and a minimum mixing cycle after the addition of the GLENIUM 51, of 60 seconds for

forced action mixers is recommended.

Table (6): Typical Properties of GLENIUM 51(5).

Form Viscous Liquid

Colour Light Brown

Relative Density 1.08 – 1.15 @ 25°C

pH 6.6

Viscosity 128 +/- 30 cps @ 20°C

Transport Not classified as dangerous

Labeling No hazard label required

4.7. Reinforcing Steel All the reinforcing steel bars, used in this study, are deformed and of Ukrainian origin with a

nominal diameter (Ф) of (4,6,12,16,20, 25 and B.R.C Ф 6) mm.

Table (7): Test Results of Reinforcement Steel Bars

Bars Diameters

(mm)

Yield stress

(ƒy),(MPa)

Ultimate stress

(ƒt),(MPa)

Estimated Modulus

of Elasticity

(Es),(MPa)×103

4 445 670 200

6 460 662 200

B.R.C Φ6 529.25 960.95 200

12 476.13 680.86 200

16 489.57 734.36 200

20 505.17 727.44 200

25 486.36 719.81 200

4.8. Steel Fibers (SF) FIBERFORCE® is cold drawn wire steel fiber meeting the ASTM A820-96 Type 1

requirements as well as C1116 section 4.1.1 requirements.

4.9. Polymer or Polypropylene Fibers (P.F.)(5)

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Table (8) illustrate the typical properties of polypropylene fibers (RHEOFIBER®) which are used

in this experimental study.

Table (8): Typical Properties of RHEOFIBER®(5)

Specific gravity 0.91 g/cm3

Alkali content Nil

Sulphate content Nil

Area entrainment Area content of concrete will not be significantly increased

Chloride content Nil

Constituents Polymerized polypropylene

Fiber diameter 18 micron

Fiber length 12 mm

Surface area 230 m2/kg min.

Young’s modulus 3500-3900 MPa

Tensile strength Min 350 MPa

Melting point 160°C

4.10. Pozzolanic Additives (micro-silica)(5)

Table (9): Typical Properties of MEYCO® MS610 (5)

Form Powder

Colour Grey

Bulk density 550-700 kg/m3

Chloride content < 0.1%

5. Results of Fresh SCC Tests According to the fresh tests of the four self-compacting concrete mixes, the results are shown

in Table (10).

6. General Behavior of Tested T-Beams Test results that describe behavior of tested T-Beams are shown in Tables (11-13) as hereafter.

294


Table(10): The Fresh Tests Results of SCC.

V-Funnel L-Box

Mix

Slump

Flow

(mm)

T500mm

(sec) TV

(sec)

TV5

(sec)

Blocking

Ratio

T20

(sec)

T40

(sec)

SCC1 680 3.00 10 12 0.8 2 2.5

SCC2 780 2.5 7 8 1.0 1.0 2.0

SCC3 725 3.00 11.5 13.5 0.953 1.5 3.25

SCC4 760 3.50 9.00 10.50 0.94 0.9 2.0

permissible

limits

according to

EFNARC(4)

(650-800) (2-5) (6-12) (6-15) (0.8-1.0) ------ ------

SCC: Self – Compacting Concrete.

Table (11): the experimental and calculated first crack loads of tested T-Beams.

Beam No. Pcr , (kN)

(Exp.)

Pcr , (kN)

(ACI 318)

Pcr (Exp.) /

Pcr (ACI

318-08)

Pu , (kN)

(Exp.)

Pcr (Exp.) /

Pu (Exp.)

(%)

B1-G1 62 60.757 1.0205 595 10.420

B2-G1 63.5 62.772 1.0116 590 10.763

B3-G1 54 52.148 1.0355 745 7.248

B4-G1 61 60.048 1.0159 512 11.914

B1-G2 65 63.411 1.0251 665 9.774

B2-G2 65.5 64.982 1.0080 655 10

B3-G2 57 54.103 1.0536 647 8.810

B4-G2 51 48.969 1.0415 598 8.528

B1-G3 60 58.997 1.0170 592 10.135

B2-G3 58.5 57.642 1.0149 586 9.983

B3-G3 71 69.085 1.0277 678 10.472

B4-G3 66 64.140 1.0290 505 13.069

295


6.1. Ductility (μd) Ductility is usually defined as the energy absorbed by the material until a complete failure

occurs(8). In the present work, the experimental ductility factors are calculated according to the

deflection at ultimate load divided by the deflection at yielding (9) which can be found from the

load value in (the load-deflection curve) when this curve is transformed from elastic state to plastic

state, the deflection value which in this load value must be taken such as (B1,B2,B3 and B4 of G1),

the yield deflections values (δy = 2.15mm @ 300kN,δy = 1.65mm @ 225kN,δy = 1.83mm @

210kN and δy = 0.855mm @ 100kN), also the yield deflections values for (B1, B2, B3 and B4 of G2)

are (δy = 1.20mm @ 210kN, δy = 0.98mm @ 150kN,δy = 0.83mm @ 100kN and δy = 0.42mm @

70kN) and the yield deflections values for (B1, B2, B3 and B4 of G0) are (δy= 6.90mm @ 500kN, δy

= 4.35mm @ 425kN, δy = 3.97mm @ 435.71kN and δy = 1.5mm @ 150kN) respectively. As

shown in Table (12).

Table (12): the experimental deflection ductility factors of tested T-Beams.

Deflection (mm) Group No. Beam No.

δy δu

Ductility

Factor

(μd = δu / δy)

B1 2.15 7.05 3.2791

B2 1.65 7.33 4.4394

B3 1.83 10.22 5.5847 G1

B4 0.855 7.91 9.2515

B1 1.20 7.40 6.1667

B2 0.98 8.30 8.4694

B3 0.83 7.62 9.1807 G2

B4 0.42 7.15 17.0238

B1 6.90 8.58 1.2435

B2 4.35 7.40 1.7012

B3 3.97 9.20 2.3174 G0

B4 1.5 7.35 4.9

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Table (13): Mid-span Deflections at First Crack and Service Loads of all beams

Experimentally and According to (ACI 318 – 08) Code (6).

At first crack load At service load

Experimental ACI 318 Experimental ACI 318

Group

No.

Beam

No.

Pcr

(kN) δcr (mm) δcr (mm)

Psr = (Pu /

1.6),(kN)

δsr

(mm) δsr (mm)

B1 62 0.318 0.285 371.88 2.919 2.820

B2 63.5 0.372 0.286 368.75 3.768 2.615

B3 54 0.390 0.291 465.63 5.356 2.881

G1

B4 61 0.469 0.280 320 3.400 2.498

B1 65 0.275 0.225 415.63 3.913 2.871

B2 65.5 0.369 0.224 409.38 3.694 2.593

B3 57 0.496 0.282 404.38 3.944 2.852

G2

B4 51 0.305 0.272 373.75 3.785 3.117

B1 60 0.450 0.347 370 4.220 3.170

B2 58.5 0.510 0.345 366.25 3.594 3.241

B3 71 0.725 0.249 423.75 3.849 2.418

G0

B4 66 0.726 0.245 315.63 3.556 2.108

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7. Conclusions According to the test results,the following conclusions were obtained:

1. Adding polypropylene fibers of the type of (RHEO‐FIBERS®)(٥) in the rate of (1kg / m3) to the self‐

compacting concrete mix results in high improvement in the cracks patterns (a decrease in the

crackwidths, heights and the numbers of developed cracks.

2. Increasing the steel reinforcing ratio (ρ%) improves the ductility by increasing the ultimate

load as the ultimate deflection increased.Yielding deflection reduced due to high

reinforcement. The ductility factor increased by (0.2265 – 0.4577), but when the

polypropylene fibers are added in a combination with steel bar ratio (ρ%) they results in

good improvement in beam ductility by (0.5846 – 4.0514).Ductility of beams also increases

when the steel fibers of type of (FIBERFORCE® steel fibers)(7) are added in the range of

(4.9232 – 12.1238).

3. Adding the polypropylene fiber to the self-compacting concrete mix, has a minor effect on

the tensile strength (flexural strength) of concrete ( by the range of %4.53), however, these

fibers in combination with the self-compacting concrete makes the concrete mix more

cohesive, because the self-compacting concrete is with less voids and hence gaining high

cohesion.

4. Adding steel fibers of type (FIBERFORCE®)(7) at a volume range of (Vf = %0.5 from total

concrete volume) to the self-compacting concrete mix has major effect in improving the

flexural strength of the self-compacting concrete by the range of increasing of

approximately (%6.62). This value is larger than the effect of adding polypropylene fibers

to the same mix in the same compressive strength (ƒ'c).

5. All tested T-Beams of the three groups showed cracking load,between (7.248% - 13.069%)

of the ultimate loads and the first cracks were found to occur in the constant moment

region.

6. Adding steel fibers to SCC promotes slight gain in the ultimate load capacity and lowers

midspan deflection. Therefore, itwill lower deformations in the reinforcement bars in

comparison with the T-Beams produced with only SCC or PFRSCC.

7. Increasing the reinforcement ratios (%ρ) in combination with the steel fibers results in high effect

on the reduction of deflections and increasing the ultimate loads by (11.78% ‐ 18.42%) of self‐

compacting concrete T‐Beams, but when it is increased in combination with the polypropylene

fibers, the increase in the ultimate loads was found to be in the range (0.51% ‐ 9.88%).

298


299

References [1] Carolin, A., "Improvement of load-bearing capacity exiting bridges literature review",

Technical Report, Luleä University of Technology, Sweden, 1999.

[2] I.Q.S. No.5:1984, Iraqi Standard for Portland Cement. السمنت" , ٥رقم / المواصفة العراقية *

. ١٩٨٤., بغداد , الجھاز المركزي للتقييس والسيطرة النوعية , "البورتالندي األعتيادي

[3] Iraqi Standard Specification (IQS) No.45, 1984, "Natural Sources of Aggregate Used in

Building and Concrete". Baghdad. ركام المصادر الطبيعية المستعمل في" , ٤٥رقم / المواصفات العراقية *

. ١٩٨٤, بغداد , الجھاز المركزي للتقييس والسيطرة النوعية , " الخرسانة والبناء

[4] EFNARC: Eurpean Federation Dedicated to Specialist Construction Chemicals and Concrete

Systems “Specifications and Guidelines for Self-Compacting Concrete”, EFNARC, Association

House,99 West Street, Farnham, Surrey GU9 7EN, U.K., Feb.2002, 32pp.

[5] Product Guide & Technical Data Sheets of the chemical company of BASF®for admixture and

construction systems, 2010, p860.

[6] ACI Committee 318,"Biulding Code Requirements for Structural Concrete".(ACI318M-08)

and Commentary (ACI 318R-08), ACI Manual of Concrete Practice, American Concrete Institute,

Farmington Hills, U.S.A.

[7] Data sheet of FIBERFORCE Steel Fibers, "SPI company for Composite Systems".

[8]Hussain M., Alfarabi S., Basunbul A., Baluch M.H., Al-SulaimaniG.J.,"Flexural Behavior of

Precracked Reinforced Concrete Beams Strengthened Externally by Steel Plates" ACI Structural

Journal, Vol.92, Issue.1,1995.

[9] Mohammed Abdur Rashid and AhsanulKabir, "Behavior of Reinforced Concrete Deep Beam

Under Uniform Loading",Journal of Civil Engineering, The institution of Engineers, Bangladesh,

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