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Article
EXPERIMENTAL INVESTIGATION ON THE FRESH AND HARDENED PROPERTIES OF CONCRETE INCORPORATING POLYVINYL

Author: Abo Dhaheer, M.S
Journal: Al-Qadisiyah Journal for Engineering Sciences مجلة القادسية للعلوم الهندسية ISSN: 19984456 Year: 2018 Volume: 11 Issue: 1 Pages: 134-147
Publisher: Al-Qadisiyah University جامعة القادسية

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Abstract

Polyvinyl alcohol (PVA) has undergone intensive research work that has led to confidence in its utilization in various applications. Nevertheless, its utilization as a construction material in the concrete industry still needs to be fully addressed. In this paper, an experimental study was dedicated to investigate the influence of PVA on the fresh and hardened properties of concrete. Three different strength grades, represented by water to cement ratios (w/c), of 0.4, 0.5 and 0.6, with four different PVA dosages of 1, 2, 3 and 4%, by mass of cement, were employed in the preparation of the concrete mixes. Concerning the fresh properties, results showed that there was a significant contribution of PVA to the workability in all produced mixes, irrespective of w/c ratio. In addition, the initial and final setting time of cement pastes modified with 2% PVA were longer than that of the control paste. In term of the hardened properties, results demonstrated that the compressive (fcu) and splitting tensile (fst) strengths of concrete are dominated by amounts of PVA in the mix and w/c ratios. With the high and moderate w/c ratios, they increased when up to 2% PVA was used, and thereafter decreased. However, with the low w/c, PVA did not provide any improvement in the strength, but instead, it decreased the strength when more than 2% was added. The findings revealed also that increasing PVA content resulted in a significant reduction in total water absorption (TWA) of concrete specimens. The larger the PVA contents the lower is the TWA of the specimens


Article
Investigation of Biological Activity, Open Porosity and Water Absorption of Ternary Polymeric Blend (Polymethylmethacrylate / Starch) used for Bone Scaffold
النشاط البيولوجي ، المسامية المفتوحة وامتصاص الماء للخليط البوليميري الثلاثي (بولي مثيل ميثا اكريلايت/ النشا) المستخدم في سقالة العظام

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Abstract

In this study a fabrication of three groups of biological system for bone scaffold, which consist of first group samples (Acrylic bone cement: % X poly methyl meth acrylate ), second group samples (poly methyl meth acrylate: % X Acrylic bone cement), with selected weight percentages of second material are (5, 10,15 and 20 % wt.) and third group, (Acrylic bone cement: 15 % poly methyl meth acrylate : % X starch) with selected weight percentage ratios of starch are (2, 4 and 6 %wt.). In vitro biological activity and water absorption have been studied. The results clarified that the in vitro biological activity test showed that all fabricated samples have no biological influence on the gram positive bacteria Bacillus subtilis and gram negative bacteria Escherichia coli . The results show that the first group of polymer blend have low open porosity and water uptake capacity than a second group. The increasing in starch weight fraction for the third group led to increasing in open porosity and water absorption

في هذه الدراسة تم تصنيع ثلاث مجاميع من النظام البيولوجي لسقالة العظم ,تكونت المجموعة الاولى من ( السمنت العظمي : % X بولي مثيل ميثا اكريلايت) , اما عينات المجموعة الثانية فتكونت من ْ% : (بولي مثيل ميثا اكريلايت السمنت العظمي X ) بنسب )في حين ان عينات المجموعة الثالثة تمثلت 20, 15 ,10 ,5 ( وزنية محددة من المادة الثانية و هي % 15 : ( السمنت العظمي بولي مثيل ميثا اكريلايت .)تمت دراسة النشاط البيولوجي وامتصاص 6 ,4 ,2( : % النشا) بنسب وزنية محددة من النشا و هي X الماء في المختبر .أوضحت النتائج أن اختبار النشاط الحيوي في المختبر لجميع العينات المصنعة ليس لها تأثير بيولوجي على البكتيريا إيجابية الجرام ( والبكتريا سالبة الجرام Bacillus subtilis (B. subtilis ( أظهرت النتائج أن المسامية المفتوحة وقدرة E. coli) أمتصاص الماء للمجموعة الاولى هي أقل مما في المجموعة الثانية .وكذلك أدى تزايد الكسر الوزني للنشأ في المجموعة الثانية إلى زيادة المسامية المفتوحة وامتصاص الماء


Article
THE EFFECT OF USING RUBBER TIER AND GLASS WASTE ON THE PROPERTIES OF CEMENT MORTAR

Author: Mais Abdulrahman Abdulkareem
Journal: Journal of Engineering and Sustainable Development مجلة الهندسة والتنمية المستدامة ISSN: 25200917 Year: 2018 Volume: 22 Issue: 2 (Part-4) Pages: 84-93
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

This research studies the effect of rubber tier waste and waste glass together on the properties of cement mortar and used mixing ratio (1: 3) and has been added rubber tier waste ratio are (10%, 20%, and 30%). Has been added waste glass ratio are (10%, 20%and 30 %) and also added rubber tier waste and waste glass together ratio are (10%, 20% and 30%) by weight of the replacement of cement. This study includes mechanical properties such as compressive strength and physical properties such as water absorption, density and also setting time. The results obtained from the study that compressive strength decreases when increasing the percentage of additives of mortar .The water absorption increased when the percentage of additive is increased. The density decrease when both percentage of additive increase in mortar cement. Also, the setting time increases when the percentage of additive is increase.


Article
EFFECTE OF FLY ASH AS A SUSTAINABLE MATERIAL ON LIGHTWEIGHT FOAMED CONCRETE MIXES

Authors: Ayad Zeki Saber Agha --- . Mohamad Adnan Basher --- Esra’a Abdul Salam Mahmood
Journal: Journal of Engineering and Sustainable Development مجلة الهندسة والتنمية المستدامة ISSN: 25200917 Year: 2018 Volume: 22 Issue: 2 (Part-4) Pages: 108-124
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

The use of fly ash as a sustainable material in concrete gained significant importance at present, due to its environmental and economic benefits. Besides, it may improve the long-term durability of concrete. This study presents the effect of moderate contents of fly ash as a partial replacement of cement on fresh and mechanical properties of cement mortar and lightweight foamed concrete. The results showed that the use of fly ash improved workability and reduced the density and water absorption of foamed concrete, while reduced the concrete strength at early age, however the concrete strength increases after 28 days.


Article
Mechanical and Thermal Stability of Epoxy – TEOS Hybrids Materi-als using Sol-Gel Method

Authors: Seenaa Ibrahim Hussein --- Nadia Abbas Ali --- Harith Ibrahim Jaafar --- Zaniab Raheem Muslem
Journal: Al-Mustansiriyah Journal of Science مجلة علوم المستنصرية ISSN: 1814635X Year: 2018 Volume: 29 Issue: 3 ICSSSA 2018 Conference Issue Pages: 145-149
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

Sol-gel method is the simplest method and has to preparation of nano particles, nano fibers, and nano flaks. The preparation of hybrid epoxy thermosets enables their improvement in characteristics such as mechanical properties (bending,and hardness), thermal properties. The effect of water absorption on bending and hardness test for tetraethylorthosilicate (TEOS) and epoxy hybrid have been investigated. TEOS with (0%,2%,4%,6%and 8%) volume percentage mixed with epoxy to prepared sheets of hybrid, these sheets cut as samples for ASTM water absorption, bending and hardness tests.The results show that, adding TEOS to epoxy will increase absorbance of water. bending test shows that there are increase in values of bending stress with increasing TEOS but after immersion in water all the values for bending stress will reduce. Hardnessvalues at least for the samples immersion in water from dry samples, occur the diffusion of molecules water in the polymer and hybrids leads to space molecular chains for each other and decrease the hardness values. Thermal stability of hybrids increase with increasing TEOS ratio, the glass and decomposition temperature were shift compare with epoxy pure.

اتباع طريقة كيميائية هي طريقة الصل–جل وهي ابسط الطرق في تحضير جسيمات والياف ومتراكباتنانوية ، بعد تحضير المتراكب الهجين مع الايبوكسي لتحسين الخصائص الميكانيكية والخصائص الحرارية ودراسة تأثير امتصاص الماء على اختبار الانحناء والصلادة للمتراكب الهجيني TEOS مع الايبوكسي والايبوكسي المحضر بشكل متراكب هجيني وتقطيعه حسب المواصفات الامريكية لفحص امتصاص الماء والانحناء ثلاثي الابعاد والصلادة.


Article
The Influence of Clay Bricks Dust Incorporation on the Self-Curing of Cement Mortar
تأثير غبار الطابوق الطيني على الانضاج الذاتي لمونة السمنت

Author: Ahmed S. Ali احمد سلطان علي
Journal: Journal of Engineering مجلة الهندسة ISSN: 17264073 25203339 Year: 2018 Volume: 24 Issue: 12 Pages: 73-83
Publisher: Baghdad University جامعة بغداد

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Abstract

Self- curing is the potential of lightweight aggregate to absorption great amount of water thru mixing which prominently can moves to the paste during hydration process. Self- curing empowers a water to be distributes more evenly act out the cross section. Whereas, the external curing water is only able to penetrate several millimetres into concrete with low water cement ratio. Brick dust accumulates in the demolish site creates serious environmental contamination. This study investigates the effect of brick dust recovered from construction site on the Properties of mortar cured in three curing conditions. Mortar in this study produced using BD as cement additive with (2, 4, 6, and 8) % by weight of cement. BD was used as cement replacement (1, 2, 3, and 4) % by weight of cement. Three curing conditions were experienced in this study to identify whether BD can be used as self- curing agent. Compressive strength, Fresh and hardened density, water absorption, and modulus of rupture were tested. The results of compressive strength and modulus of rupture were decreased when BD used as cement additive and as cement replacement increase. However, they were higher for mortars cured in air conditions than those cured in water and partially water curing. Water absorption, was increased with the increase of (BD) when used as cement additive and replacement. It was indicated BD could be used as self- curing agent and could replace cement at specific ratios which will achieve economical profits and reduce environmental pollution.Self- curing is the potential of lightweight aggregate to absorption great amount of water thru mixing which prominently can moves to the paste during hydration process. Self- curing empowers a water to be distributes more evenly act out the cross section. Whereas, the external curing water is only able to penetrate several millimetres into concrete with low water cement ratio. Brick dust accumulates in the demolish site creates serious environmental contamination. This study investigates the effect of brick dust recovered from construction site on the Properties of mortar cured in three curing conditions. Mortar in this study produced using BD as cement additive with (2, 4, 6, and 8) % by weight of cement. BD was used as cement replacement (1, 2, 3, and 4) % by weight of cement. Three curing conditions were experienced in this study to identify whether BD can be used as self- curing agent. Compressive strength, Fresh and hardened density, water absorption, and modulus of rupture were tested. The results of compressive strength and modulus of rupture were decreased when BD used as cement additive and as cement replacement increase. However, they were higher for mortars cured in air conditions than those cured in water and partially water curing. Water absorption, was increased with the increase of (BD) when used as cement additive and replacement. It was indicated BD could be used as self- curing agent and could replace cement at specific ratios which will achieve economical profits and reduce environmental pollution.Self- curing is the potential of lightweight aggregate to absorption great amount of water thru mixing which prominently can moves to the paste during hydration process. Self- curing empowers a water to be distributes more evenly act out the cross section. Whereas, the external curing water is only able to penetrate several millimetres into concrete with low water cement ratio. Brick dust accumulates in the demolish site creates serious environmental contamination. This study investigates the effect of brick dust recovered from construction site on the Properties of mortar cured in three curing conditions. Mortar in this study produced using BD as cement additive with (2, 4, 6, and 8) % by weight of cement. BD was used as cement replacement (1, 2, 3, and 4) % by weight of cement. Three curing conditions were experienced in this study to identify whether BD can be used as self- curing agent. Compressive strength, Fresh and hardened density, water absorption, and modulus of rupture were tested. The results of compressive strength and modulus of rupture were decreased when BD used as cement additive and as cement replacement increase. However, they were higher for mortars cured in air conditions than those cured in water and partially water curing. Water absorption, was increased with the increase of (BD) when used as cement additive and replacement. It was indicated BD could be used as self- curing agent and could replace cement at specific ratios which will achieve economical profits and reduce environmental pollution.Self- curing is the potential of lightweight aggregate to absorption great amount of water thru mixing which prominently can moves to the paste during hydration process. Self- curing empowers a water to be distributes more evenly act out the cross section. Whereas, the external curing water is only able to penetrate several millimetres into concrete with low water cement ratio. Brick dust accumulates in the demolish site creates serious environmental contamination. This study investigates the effect of brick dust recovered from construction site on the Properties of mortar cured in three curing conditions. Mortar in this study produced using BD as cement additive with (2, 4, 6, and 8) % by weight of cement. BD was used as cement replacement (1, 2, 3, and 4) % by weight of cement. Three curing conditions were experienced in this study to identify whether BD can be used as self- curing agent. Compressive strength, Fresh and hardened density, water absorption, and modulus of rupture were tested. The results of compressive strength and modulus of rupture were decreased when BD used as cement additive and as cement replacement increase. However, they were higher for mortars cured in air conditions than those cured in water and partially water curing. Water absorption, was increased with the increase of (BD) when used as cement additive and replacement. It was indicated BD could be used as self- curing agent and could replace cement at specific ratios which will achieve economical profits and reduce environmental pollution.

الانضاج الذاتي يعبر عن قدرة الركام الخفيف الوزن على امتصاص كمية كبيرة من الماء خلال عملية الخلط وحدوث الاماهة, الانضاج الذاتي يمكن الماء من ان يتوزع بانتضام خلال مقطع الخرسانة , في حين ان الانضاج الخارجي يتغلل الماء مليمترات قليلة داخل الخرسانة خصوصا عندما تكون نسبة الماء الى الاسمنت منخفضة. تراكم غبار الطابوق سواء في اماكن البناء او الهدم يخلق مشاكل بيئية خطيرة.هذه الدراسة تبحث في تاثير غبار الطابوق على خصائص المونة. تم اضافة غبار الطابوق الى مونة السمنت كنسبة من وزن السمنت وبنسب (2, 4, 6, 8) % الى جانب ذلك تم اضافة غبار الطابوق الى المونة كاستبدال وزني من وزن السمنت المستخدم وبنسب (1, 2, 3, 4) % . تم تطبيق ثلاث طرق للانضاج لتقييم استخدام مسحوق الطابوق الطيني كعامل انضاج ذاتي.بينت النتاج ان قيم مقاومة الانضغاط ومعاير الكسر تقل بزيادة نسبة غبار الطابوق كاضافة او استبدال وزني من السمنت. على اية حال هذه القيم كانت اعلى من قيم النماذج سواء تم انضاجها بشكل جزئي بالماء او كليا بالهواء في حين ان امتصاص النماذج للماء يزداد بزيادة نسبة غبار الطابوق كاضافة او استبدال من وزن السمنت. بناءا على ذلك فان غبار الطابوق يمكن ان يستخدم في عملية الانضاج الذاتي مما يؤدي الى مردود اقتصادي ويقلل من التلوث البيئي.

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