research centers


Search results: Found 4

Listing 1 - 4 of 4
Sort by

Article
Effect of Metakaolin on Properties of Lightweight Porcelinate Aggregate Concrete

Authors: Nada M. Fawzi --- Kalil I. Aziz --- Sheelan M. Hama
Journal: Journal of Engineering مجلة الهندسة ISSN: 17264073 25203339 Year: 2013 Volume: 19 Issue: 4 Pages: 439-452
Publisher: Baghdad University جامعة بغداد

Loading...
Loading...
Abstract

Research in Iraq has expanded in the field of material technology involving the properties of the lightweight concrete using natural aggregate. The use of the porcelinate aggregate in the production of structural light concrete has a wide objective and requires a lot of research to become suitable for practical application. In this work metakaolin was used to improve compressive strength of lightweight porcelinate concrete which usually have a low compressive strength about 17 MPa . The effect of metakaolin on compressive, splitting tensile, flexure strengths and modulus of elasticity of lightweight porcelinate concrete have been investigated. Many experiments were carried out by replacing cement with different percentages of metakaolin. The metakaolin was replaced by 5%, 10%, 15% and 20%. A control reference mix without metakaolin was made for comparison purpose. For all mixes, compressive, splitting tensile, flexure strengths and modulus of elasticity were determined at 28-day. The results showed that the using of metakaolin improve the compressive, splitting tensile, flexure strengths and modulus of elasticity of lightweight porcelinate concrete. The higher compressive, splitting tensile, flexure strengths and modulus of elasticity were found for 15% metakaolin.

توسعت البحوث في العراق في حقل تكلنوجيا المواد من ضمنها دراسة خواص الخرسانة خفيفة الوزن باستخدام ركام طبيعي. استخدام البورسلينايت كركام خفيف الوزن في انتاج خرسانة انشائية يتطلب العديد من الدراسات لفهم وتحسين خواصها لتصبح مناسبة للتطبيقات العملية. في هذه الدراسة استخدمت مادة ميتاكاؤلين كنسبة مئوية مِنْ وزنِ سمنت، لتحسين خواص خرسانة البورسلينايت الخفيفة الوزن التي تمتاز عادة بمقاومة انضغاط واطئة حوالي 17 ميكاباسكال. تم دراسة تاثير اضافة ميتاكاؤلين على كل من مقاومة الانضغاط, مقاومة الانفلاق, معامل التصدع, و معامل المرونة للخرسانة البورسلينايت الخفيفة الوزن. وقد استبدل جزء من السمنت بالنسب التالية من ميتاكاؤلين: 5%, 10%, 15%, و 20% من وزن السمنت, بالاضافة الى الخلطة المرجعية بدون اضافات لغرض المقارنة. لكل الخلطات تم قياس كل من مقاومة الانضغاط, مقاومة الانفلاق, معامل التصدع, و معامل المرونة بعمر 28 يوم. وقد وجد بان اسبتدال نسبة 15% من سمنت بميتاكاؤلين تحسن مقاومة الانضغاط, مقاومة الانفلاق, معامل التصدع, و معامل المرونة.


Article
Effectiveness of Glass Wastes as Powder on Some Hardened Properties of Concrete

Authors: Mohamed Mahir Yassen --- Akram Shakir Mahmoud --- Sheelan M. Hama
Journal: AL-NAHRAIN JOURNAL FOR ENGINEERING SCIENCES مجلة النهرين للعلوم الهندسية ISSN: 25219154 / eISSN 25219162 Year: 2019 Volume: 22 Issue: 1 Pages: 14-17
Publisher: Al-Nahrain University جامعة النهرين

Loading...
Loading...
Abstract

This paper present glass waste material reusing in concrete as partial replacement of cement. Some hardened properties like compressive and flexural strengths, modulus of elasticity and % absorption was made. The effect of glass powder on these properties was examined compared to reference specimens without glass powder. Five percentage was tested: 0%(reference), 10%, 15%, 20% and 25%. From tests results one can conclude that replacing cement partially by glass powder enhanced strengths of concrete (compression and flexural) up to 20% replacing level Using glass powder as partial replacement of cement improved strengths and modulus of elasticity of concrete. The %absorption decrease with increasing of glass powder content. The results show that utilization of waste glass as powder in concrete can reduce amount of cement which save cost besides its environmental benefits.


Article
Fresh, Mechanical Properties and Impact Resistance Behavior of Eco-Friend Self-Compacted Concrete

Authors: Mohammed T. Nawar --- Alhareth M. Abdulghafor --- Sheelan M. Hama
Journal: AL-NAHRAIN JOURNAL FOR ENGINEERING SCIENCES مجلة النهرين للعلوم الهندسية ISSN: 25219154 / eISSN 25219162 Year: 2019 Volume: 22 Issue: 3 Pages: 208-212
Publisher: Al-Nahrain University جامعة النهرين

Loading...
Loading...
Abstract

In this work, waste glass powder from broken windows and plastic fibers from waste polyethylene terephthalate bottles are utilized to produce an economical self-compact concrete. Fresh properties (slump flow diameter, slump Flow T50, V. Funnel, L–Box), mechanical properties (Compressive strength and Flexural strength) and impact resistance of self-compact concrete are investigated. 15% waste glass powder as a partial replacement of cement with five percentages of polyethylene terephthalate plastic waste were adopted: 0% (reference), 0.5%, 0.75%, 1%, 1.25% and 1.5% by volume. It seems that the flow ability of self-compact concrete decreases with the increasing of the amount of plastic fibers. The compressive strength was increased slightly with plastic fiber content up to (0.75%), about 4.6% For more than (0.75%) plastic fiber. The compressive strength began to decrease about 15.2%. The results showed an improvement in flexural strength and an impact on the resistance in all tested specimens’ content of the plastic fibers, especially at (1.5%) fibers.


Article
Improving Strengths of Porcelanite Aggregate Concrete by Adding Chopped Carbon Fibers
تحسین مقاومات خرسانة االبورسیلانایت الخفیفة الوزن باستخدام الیاف الكاربون

Authors: Sheelan M. Hama شیلان محمود حمھ --- Shaho Mahmoud Hama شاھو محمود حمھ --- Mohammed H. Mhana محمد حمود مھنا
Journal: AL-NAHRAIN JOURNAL FOR ENGINEERING SCIENCES مجلة النهرين للعلوم الهندسية ISSN: 25219154 / eISSN 25219162 Year: 2018 Volume: 21 Issue: 1 Pages: 161-165
Publisher: Al-Nahrain University جامعة النهرين

Loading...
Loading...
Abstract

In this work chopped carbon fibers are used to improve tensile strength of Porcelanite lightweight aggregate concrete. Silica fume was added in order to improve the mixes compressive strength. Silica fume increase water demand and using fibers reduce workability, to improve workability and decrease water demand high rang super plasticizers are used. The results showed that compressive strength, splitting tensile strength, modulus of elasticity of carbon fibers Porcelanite lightweight aggregate concrete increase with increasing of carbon fiber up to 2% compared to reference Porcelanite lightweight aggregate concrete without fibers. The percentages of increasing were 14.40%, 68.00%, and 10.66% for compressive strength, splitting tensile strength, and modulus of elasticity, respectively. Flexural Strength continues in increase with increase of fibers. The dry unite weight of mixes with chopped fiber decrease with increase of fiber percentage. Besides the chopped carbon improved the ductility of Porcelanite lightweight aggregate concrete and that clear from stress-strain relationship.

Keywords

Listing 1 - 4 of 4
Sort by
Narrow your search

Resource type

article (4)


Language

English (4)


Year
From To Submit

2019 (2)

2018 (1)

2013 (1)