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Article
Effect of Micro Powder on Mechanical and Physical Properties of Glass Fiber Reinforced Epoxy Composite

Authors: Aseel Basim Abdul-Hussein --- Fadhel Abbas Hashim --- Tamara Raad Kadhim
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2016 Volume: 34 Issue: 7 Part (A) Engineering Pages: 1402-1414
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

In the present study, composites were prepared by Hand lay-up molding. The composites constituents were epoxy resin as the matrix, 3% volume fractions of Glass Fibers (G.F) as re enforcement and 2%, 4%, 6% volume fraction of micro powder (Aluminum Oxide Al2O3, Silicon Oxide SiO2 and Titanium Oxide TiO2) as filler. Studied the, hardness test, flexural strength, density, water absorption measurements and tests were conducted to reveal their values for each type of composite material. The results showed that the non – reinforced epoxy have lower properties than nano composites material. Measured density results had show an incremental increase with volume fraction increase and water absorption, hardness, and flexural strength had show an incremental increase with volume fraction increase and with smaller particle size.


Article
IMPROVING SOME OF PHYSICAL PROPERTIES OF CEMENT MORTAR BY THE ADDITION OF GLASS FIBERS
تحسين بعض الخواص الفيزيائية للملاط بإضافة الياف الزجاج

Authors: Besma Mohammed Fahad --- Mustafa Mohammed Hamza
Journal: Journal of Engineering and Sustainable Development مجلة الهندسة والتنمية المستدامة ISSN: 25200917 Year: 2016 Volume: 20 Issue: 6 Pages: 195-206
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

Glass fibers reinforced mortar is a modern composite material in the field of construction. This composite consists of cementitious matrix includes cement, sand and water and reinforcement which is represented by glass fibers. This study aims to show the effect of addition random dispersed glass fibers and layers glass fibers on water absorption, velocity of ultrasound wave passing through the reinforced mortar and acoustic impedance of mortar. Mixtures of 1:2 cement/sand ratio and 0.5 water/cement ratio were prepared to make the mortar. Two series of mortars reinforced by glass fibers (random and layers) were prepared. Each series were reinforced with different percentage (0.54, 0.76, 1.1 and 1.42)wt.%. Glass fibers reinforced mortar exhibits better properties than plain mortar. The increasing in glass fibers addition caused an improvement on mortar by reduction of water absorption, ultrasound wave velocity and acoustic impedance. The addition of glass fibers layers showed better properties than random addition after curing for 7 and 28 days.

الملاط المدعم بألياف الزجاج هي مادة مركبة حديثة في مجال الإنشاءات. تتألف هذه المادة المركبة من مادة الأساس الإسمنتية ومادة التقوية. تتكون مادة الأساس الإسمنتية من الإسمنت والرمل والماء كما تمثلت مادة التقوية بألياف الزجاج. تهدف هذه الرسالة لإظهار تأثير اضافة الياف الزجاج العشوائية وطبقات الياف الزجاج على امتصاصية الماء و سرعة الموجة فوق الصوتية النافذة خلال الملاط المدعم بألياف الزجاج بالإضافة الى دراسة الممانعة الصوتية. تم تحضير خلطات من الملاط بنسبة خلط وزنية (1:2 اسمنت- رمل) ونسبة الماء الى الإسمنت (0.5). كما تم تحضير سلسلتين من الملاط المدعم بألياف الزجاج (عشوائية و طبقات). تم اضافة نسب وزنية مختلفة من الياف الزجاج لكلا السلسلتين (0.54, 0.76, 1.1, 1.42)%. المونة المدعمة بألياف الزجاج اظهرت خواص افضل منها في الحالة الغير مدعمة. الزيادة في اضافة الياف الزجاج اظهرت تحسينا في خواص المونة من خلال تقليل كل من قابلية امتصاص الماء و سرعة الموجة فوق الصوتية والممانعة الصوتية.


Article
Study the Effects of Nano-Materials Addition on Some Mechanical Properties of Cement Mortar

Authors: F.A. Rasin --- L.K. Abbas --- M.J. Kadhim
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2017 Volume: 35 Issue: 4 Part (A) Engineering Pages: 348-355
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

This research involves nano-materials addition and interaction with cement mortar behavior for many mortar samples under variable curing time with constant water to cement ratio (W/C = 0.5). Some mechanical properties such as (compressive and flexural strength tests), durability (by water absorption test) were studied. The effect on the (Al-Mass cement) Ordinary Portland Cement (OPC) type (I) by additives with small amounts of nano-particles (SiO2) and (Al2O3) were investigated in this research. The nano materials additives were added on the mixture of mortar with the percentages (1, 2, 3, 4 and 5%) for both nano materials with constant (W/C) ratio and also the amount of the fine aggregate used three times the amount of cement. The results shows that, the strength of the mortar consist both nano materials give better properties than mortar without nano materials in all tests. But nano silica additive gives good properties up to (3%) than mortar with nano alumina additive which give proprietress up to (2%).


Article
Study the Physical Properties of Medium Density Fiberboard Utilized by Hybrid Mixture of Efb Fiber and Kenaf Fiber

Authors: Amamer Redwan --- Khairiah Haji Badri --- Azizah Bahrum
Journal: Al-Nahrain Journal of Science مجلة النهرين للعلوم ISSN: (print)26635453,(online)26635461 Year: 2019 Volume: 22 Issue: 2 Pages: 27-30
Publisher: Al-Nahrain University جامعة النهرين

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Abstract

In this study, a new hybrid medium density fiberboard was formulated by utilizing a fiber mixture composing of 50:50 empty fruit bunch and kenaf fiber coupled with palm-based pre-Polyurethane functioning as a binder. Kenaf as well as Empty fruit bunch fibers had a size range of 300 to 500 μm. Aluminum trihydroxide was used as the fire retardant at loading percentage of 0, 5, 10, and 15 wt% of total mass of the matrix. Water absorption property for hybrid-MDF showed a different trend in water absorption capability and this can be correlated to the strong dependence on the interface adhesion between fiber and the polymer matrix. The water absorption decreased as the loading level of Aluminum trihydroxide increased (6.5 – 2.3%) due to that fibers are held to each other through the interfacial bonding in the presence of Aluminum trihydroxide.


Article
Assessing the Dynamic Behavior of Asphalt Stabilized Gypseous Soil
تقييم التصرف الداينميكي للتربة الجبسية المحسنة بالاسفلت

Author: Mahmood D. Ahmed
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2014 Volume: 32 Issue: 4 Part (A) Engineering Pages: 822-841
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

The study presents the test results of stabilizing gypseous soil embankment obtained from Al- Faluja University Campus at Al-Ramady province. The laboratory investigation was divided into three phases, the physical and chemical properties; the optimum liquid asphalt (emulsion) requirements (which are manufactured in Iraq) were determined by using one dimensional unconfined compression strength test. In the first phase , the optimum fluid content was 11% (6% of emulsion with 5% water content). At phase two, the effect of aeration technique was investigated using both direct shear and permeability test. At phase three, a laboratory soil model of dimensions 50x50x30 cm was used as a representative of gypseous soil; pure soil, and asphalt stabilized soil have been compacted in five layers after practicing an aeration technique at maximum dry density (modified compaction) cyclic loading test was carried out on four gypseous soil models, two of them were pure soil under (dry and absorbed condition), and the other two were stabilized with emulsion also under (dry and absorbed condition). The impact of charging the hydraulic conductivity due to asphalt stabilization was investigated and the vertical deformations were determined using LVDT. For the pure soil in dry condition the vertical settlement at the top surface was (7.45 mm) at (157 load cycles), while for pure soil model under absorbed condition, the water was raised to the surface in three days , so the vertical settlement at the top surface was (12.5 mm) at (29 load cycles), this means that the pure gypseous soil under absorbed condition show reduction in strength by(85%). When the stabilized soil is in dry condition, the vertical settlement at the top surface was (9.75 mm) at (911 load cycles), while the soil was stabilized and subjected to water absorbed for seven days. The water stopped rising at second layer which is the same inlets level from the bottom, and the vertical settlement was (10.47 mm) at (897 load cycles), so there is no change in strength at failure.

التربة الجبسية لهذا البحث احضرت من جامعة الفلوجة مدينة الرمادي, الفحوص المختبرية قسمت الى ثلاث اقسام: القسم الاول ايجاد الخواص الفيزياوية والكيمياوية, والنسبة المثلى لمستحلب الاسفلت المصنوع في العراق التي وجدت من فحص مقاومة الضغط اللامحصور حيث كانت النسبة المثلى للساثل هي 11% ( 6% مستحلب الاسفلت + 5 % ماء) , وبرنامج تضمن الفحوص العملية ايجاد مقاومة الانضغاط, مقاومة القص المباشر, النفاذية و الانضمام بأتجاه واحد للتربة الجبسية في حالتها الجافة والرطبة. القسم الثاني استعملت تقنية التهوية من خلال فحص القص المباشر , اما القسم الثالث فقد تم تسليط حمل دوري و تم استعمال صندوق بأبعاد (50 * 50 * 30) سم مثقب من الثلث الاسفل للسماح للماء من ملامسة التربة و مقدار موصوليتها للماء وللتربة المحسنة وغير المحسنة.حيث تم عمل خمس طبقات بسمك( 6) سم بقيمة الكثافة المحدولة المعدلة و ثم تسليط حمل دوري من خلال موديل مصنع مسبقا وعن طريق جهاز ( LVDT) تم قياس الهطول العمودي للترب المحسنة وغير المحسنة تحت تأتير التوصيل الهيدروليكي و ملاحظة ديمومة التربة المحسنة لمنع الماء من الصعود عبر التربة. وقد وجد ان نسبة التوصيل الهيدروليكي للتربة غير المحسنة الى سطح التربة بمدة قدرها( 3 ) أيام بمعدل هطول (12.5) ملم تحت تسليط حمل دوري قدره 29 دورة تحميل, و بالنسبة للنموذج غير المعرض للغمر فمعدل الهطول (7.45) ملم تحت تسليط حمل دوري (157) دورة تحميل. وقد وجد ان التوصيل الهيدروليكي للتربة المحسنة بمدة قدرها ( 7 ) أيام لم يتجاوز فتحات دخول الماء من الثلث السفلي و بمعدل هطول (10.75) ملم تحت تأثير حمل دوري قدره (897) دورة تحميل, اما بالنسبة للنموذج المحسن وغير المعرض للغمر فقد وجد معدل الهطول (9.75) ملم تحت تأثير حمل دوري مقداره (911) دورة تحميل, بملاحظة عدم تغير مقاومة التربة.


Article
Study the Effect of Nano Ceramic Particles on Some Physical Properties of Acrylic Resins

Author: Q.A. Hamad
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2017 Volume: 35 Issue: 2 Part (A) Engineering Pages: 124-129
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

In the present research, study the effect of adding two different types of reinforcing particles, which included: nano-alumina (nano-Al2O3) and nano-silica (nano-SiO2), that added with different volume fractions of (1%, 2% and 3%), on some physical properties of composite prosthesis complete denture base materials by using self (cold) cure poly methyl methacrylate (PMMA) resin as new fluid resin matrix. In this research, the composite prosthetic dentures specimens consist of two groups were prepared by using (Hand Lay-Up) method according to the types of reinforced particles, which includes: the first group consists of PMMA resin reinforced by nano-alumina particles, and the second group consists of PMMA resin reinforced by nano-silica particles. The physical tests were performed on these specimens include (water absorption test and thermal behaviors test). The result of this study showed the values of (thermal conductivity and thermal diffusivity) properties increased with increasing the volume fraction of both (nano-Al2O3 and nano-SiO2) particles in PMMA complete denture base materials. While, the values of (water absorption and specific heat) properties decreased. In addition, the addition of (nano-Al2O3) particles has a noticeable effect on the all properties of composite material for prosthetic denture base specimens more than the (nano-SiO2) particles.


Article
EFFECT OF THE ADDITION OF STYRENE–BUTADIENE RUBBER LATEX ON THE WATER ABSORPTION AND COMPRESSIVE STRENGTH OF CRUMB RUBBER-MORTAR
دراسة تأثير اضافة مطاط الستايرين-بيوتادين على امتصاصية الماء ومقاومة الانضغاط للملاط - مفروم المطاط

Authors: Besma Mohammed Fahad --- Ali Isam Mohsin
Journal: Journal of Engineering and Sustainable Development مجلة الهندسة والتنمية المستدامة ISSN: 25200917 Year: 2016 Volume: 20 Issue: 1 Pages: 194-205
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

: In this research different mixes were prepared with Cement-Sand ratio (1:3) and Water- Cement (0.5) by weight. Four sets were prepared by partially or full replacing the sand with crumb rubber tire to fabricate the Crumb Rubber-Mortar (CRM) mixtures. The first two sets include fine crumb rubber with particles size (0.3-1 mm), The other set include coarse crumb rubber with particles size (1.18-2.36 mm).The third and fourth sets were prepared as the same first sets but with the addition of (7%) Styrene–Butadiene Rubber (SBR) latex by weight of cement. Each set was consist of different percentage of replacing the sand by crumb rubber (10,30,50,100%) by volume. Tests were conducted, including water absorption and compressive strength. Several results obtained before and after the addition of Styrene-Butadiene Rubber (SBR) which shows an increase in crumb rubber percentage cause decrease in compressive strength and water absorption; while as the density increases the compressive strength and water absorption increased before the addition of SBR. After the addition of SBR to the crumb Rubber-Mortar the compressive strength and water absorption are improved. In general fine crumb Rubber-Mortar have better properties than coarse crumb Rubber-Mortar.

تناول البحث تحضير خلطات مختلفة للملاط بنسبة وزنية (1:3 أسمنت- رمل) ونسبة الماء الى الاسمنت (0.5) , حيث حضرت اربع مجاميع وذلك باستبدال جزئي او كلي للرمل مع مطاط الاطارات المفرومة لتصنيع خلطات ملاط - مفروم المطاط (CRM). تضمنت المجموعتين الاولى والثانية مفروم اطارات بدون اضافة مطاط الستايرين-بيوتادين (SBR) احدهما بحجم جزيئي ناعم (0.3-1 mm) و الاخرى تضمنت مفروم اطارات خشن بحجم جزيئي (1.18-2.36 mm) .اما المجموعتين الثالثة والرابعة فحضرت بنفس مواصفات المجاميع الاولى ولكن بعد اضافة(7%) SBR من وزن الاسمنت. تم استبدال الرمل بمفروم المطاط (10,30,50,100%) استبدالاً حجمياً لكل المجاميع. الفحوصات التي اجريت تتضمن امتصاصية الماء ومقاومة الانضغاط. حيث تم الحصول على العديد من النتائج قبل وبعد اضافة (SBR) التي أظهرت ان الزيادة في نسبة المطاط تؤدي الى نقصان في امتصاصية الماء ومقاومة الانضغاط , في حين الزيادة في الكثافة تؤدي الى زيادة في امتصاصية الماء ومقاومة الانضغاط. بعد اضافة (SBR) الى ملاط - مفروم المطاط تم تحسين امتصاصية الماء ومقاومة الانضغاط. بصورة عامة فأن ملاط - مفروم المطاط الناعم يمتلك خواص افضل من ملاط - مفروم المطاط الخشن.


Article
COMPRESSIVE STRENGTH OF CONCRETE CONTAINING WATER ABSORPTION POLYMER BALLS (WAPB)
مقاومة انضغاط الخرسانة الحاوية على الكرات البوليمرية الممتصة للماء

Author: Ikram Faraoun Ahmed اكرام فرعون احم
Journal: KUFA JOURNAL OF ENGINEERING مجلة الكوفة الهندسية ISSN: 25230018 Year: 2017 Volume: 8 Issue: 2 Pages: 42-52
Publisher: University of Kufa جامعة الكوفة

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Abstract

Water absorbent polymers (WAP) are new component in producing building materials. They provide internal curing which reduces autogenous cracking, eliminates autogenous shrinkage, mortar strength increased, enhance early age strength to withstand strain, improve the durability, introduce higher early age compressive strength, have higher performance and reduce the effect of insufficient external curing. This research used different percent of polymer balls to choose the percent that provides good development in compressive strength with time for both water and air curing. The water absorption polymer balls in this research have the ability to absorb water and after usage in concrete they spill out the water (internal curing) and shrink leaving voids of their own diameter before shrinking, thus leads to have internal curing with air voids to reduce the samples weight .The required quantity of water for the mixes reduced due to the addition of water from the absorption polymers.

البوليمرات الممتصة للماء هي اسلوب جديد في انتاج المواد البنائية التي تحتفظ بالماء اذ تقدم معالجة داخلية والتي تقلل التشققات الذاتية وتقلل الا نكماش الذاتي وتزيد قوة المونة والخرسانة وتزيد الانفعال المبكر وتزيد مقاومة الانضغاط المبكرة وبالتالي تحسن الاداء العام وتقلل من تاثير المعالجة الخارجية. هذا البحث يستخدم نسب مختلفة من الكرات البوليمرية لاختيار النسبة المثلى التي تعطي تطور جيد لمقاومة الانضغاط مع الزمن للنماذج المعرضة للمعالجة بالماء وبالهواء .ان ) المستخدمة في هذا البحث لها القابلية على امتصاص الماء وبعد وضعها في الخلطات WAPBالكرات البوليمرية ( الكونكريتية تطرح هذا الماء (تعطي معالجة داخلية) وتنكمش تاركة فراغات داخل الخلطة الخرسانية بقدر قطر هذه الكرات قبل انكماشها مما يقلل من وزن النموذج ان كمية الماء المستخدمة لاجراء الخلطات الخرسانية تم تقليلها بما يتناسب واضافة الكرات البوليمرية الماصة للماء وحسب كمية الماء الذي ستطرحه هذه الكرات البوليمرية.


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

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