The production of self compacting concrete with normal cement content

مقدم أطروحة جامعية

al-Rawi, Luma Abdul Ghani Zghair

الجامعة

الجامعة التكنولوجية

الكلية

-

القسم الأكاديمي

قسم هندسة البناء و الإنشاءات

دولة الجامعة

العراق

الدرجة العلمية

ماجستير

تاريخ الدرجة العلمية

2008

الملخص الإنجليزي

The main object of this work is to evaluate the possibility for using reasonable cement content and fine materials 10 reduce costs of expensive chemical admixtures needed for the manufacturing of self-compacting concrete (SCC). in this work, three values of cement content arc used (rich, medium and lean mixes) with cement content of 400, 300 and 250 kg / m3 respectively, Two maximum aggregate sizes of (10 and 20mm) for each cement content are used.

The powder content material is (cementations + filler ) is maintained constant (500kg/m3) while the W/cm ratio ranges from 0.43 to 0.6S.

10 % Reactive Metakaolin Class N is used as a partial replacement by weight of cement.

On the other hand, limestone dust was used as a partial replacement by weight of the powder content (100, 200 and 250 ) kg / m* with cement content of 400, 300 and 250 kg / m5 respectively Tests were carried out on all mixes to obtain the properties of fresh concrete in terms of viscosity and stability.

The results showed that increasing the percentage of filler (limestone dust) from 20 % in rich mixes to50% in lean mixes of the total weight of the powder content reduces the amount of cement in SCC without significant effect on the fresh properties of the SCC mixes.

This conclusion is significant from the economical point of view.

The mechanical properties of hardened SCC mixes are also assessed, (compressive strength, splitting tensile strength, modulus of rupture, dynamic modulus of elasticity, ultra pulse velocity and density) Test results show that it is possible to produce SCC using low cement (250 kg / m3 ) with maximum aggregate size of 20mm .

This type of SCC has (34 ) MPa cubit compressive strength , (3.3) MPa splitting tensile strength , (5.4) MPa modulus of rupture, (24 ) GPa static modules of elasticity, (34.67) GPa dynamic modules of elasticity, (3.9) km/sec. ultra pulse velocity and (2449.9 )kg / m3 density at 28 days, while increasing the cement content from (250) to (300) and (400) kg / m3 leads to increase in the compressive strength (15% and 59%), splitting tensile strength (18 %and 42 % ) , modulus of rupture (ll %and 24 %), static modulus of elasticity (11% and 36 %), dynamic modulus of elasticity (6 %and 36 %), ultra pulse velocity (3% and 15%) and density (1% anc 2 %) respectively.

The result also shows that using 10mm maximurr aggregate size leads to an increase in the compressive strength (2% , 4% and 20%) , splitting tensile strength(2% , 5% , and 23%) , modulus o rupture (2%,5% and 15%), static modulus of elasticity(7%,2% ant 14 %), dynamic modulus of elasticity (3 %, 11% and 12%), ultra puis* Velocity (l % , 5 % and 5 %), and density (0.3% , 0.3% and ] %) at 28 day for cement content( 250,300 and 400 kg / mJ) respectively.

On the othe hand the absorption percentage is reduced to (4 %, 3% and 1%) of cement content (250 ,300 and 400) kg/m'1 respectively. The results obtained from this work show that it is possible t produce SCC with different levels of cement content (250 to400kg/mJ using local available materials which satisfy the requirements of this typ of concrete .The test data collected indicate that these materials can b used in the manufacturing of economical SCC.

التخصصات الرئيسية

الهندسة المدنية

الموضوعات

• الخرسانة
• الخواص الميكانيكية
• الخرسانة المسلحة

• APA
• MLA
• AMA

لغة النص

الإنجليزية

نوع البيانات

رسائل جامعية

رقم السجل

BIM-305689