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Article
Effect of Polypropylene Fibers on Thermal and Some Mechanical Properties of No-fines Concrete

Authors: B. H. Amanah --- O. A. Eedan --- B. S. Al-Shathr
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2017 Volume: 35 Issue: 1 Part (A) Engineering Pages: 76-82
Publisher: University of Technology الجامعة التكنولوجية

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This research aims to find the optimum percentage of polypropylene fibers that can be added to no-fines concrete. The fibers added to the (1:5, 1:6, and 1:7 mix proportions) concrete with volumetric percentages of (0.1, 0.2, 0.3, 0.4, and 0.5%), together with suitable amounts of superplasticizer to keep the flow percentage at (65-75%) using constant w/c ratio of 0.4. The results indicated that the optimum volumetric percentage of the added polypropylene fibers is 0.3% which needs small amount of superplasticizer of 0.5% by cement weight, to keep its flow equivalent to the reference mix. This percentage of fibers cause an increase in compressive strength, splitting tensile strength, and modulus of rupture of 22.5, 56.1, and 67.8% respectively when using 1:5 and 1:6 of concrete mixture. But this percentage decrease when using concrete mix proportion of 1:7 to be 8.8, 23.8, and 24% respectively. Also, results indicated that concrete density and thermal conductivity didn’t affect significantly by fibers addition.


Article
The effect of polypropylene fibers in different lengths on some properties of heat-cured acrylic resin processed by autoclave.

Author: Dr. Husam Mejbel Khalaf, B.D.S, M.Sc .* د. حسام مجبل
Journal: MUSTANSIRIA DENTAL JOURNAL مجلة المستنصرية لطب الاسنان ISSN: 18138500 Year: 2014 Volume: 11 Issue: 1 Pages: 57-66
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Background: some properties of heat-cured acrylic resin are required to beimproved (like flexural strength, hardness and porosity) by adding different types offibers like polypropylene fiber, also needed to determine these properties withaddition of polypropylene fibers and curing the polymer by autoclave. The aim of thisstudy was to evaluate the effect of adding polypropylene fibers in two differentlengths (6mm, 12mm) and concentration 2%, and the effect of autoclave processingon some properties(flexural, surface hardness and porosity).Material and method: A total No. of 120 specimens were prepared in this studyand divided into two main groups according to length of fibers (6mm,12mm) , eachmain group was subdivided into two groups according to method of adding the fiber(directly to the powder or immersed in monomer). Each group of them contain 10specimens for each test.Result: in this study, the transverse strength and surface hardness of heat curedacrylic reinforced by randomly oriented polypropylene fibers (12mm, 2%) regardlessto application method with higher significance than other groups. Fiber reinforcementand autoclave processing showed non-significant effect on porosity of heat cureacrylic resin according to ANOVA t-test.Conclusion: Reinforcement by randomly oriented polypropylene fiber (12mm,2%) added with and without immersion in monomer better than other groupsaccording to transverse strength and surface hardness with autoclave processing butthere is no effect of added fibers on porosity test.


Article
Mechanical Properties of High Performance Fiber Reinforced Concrete
الخواص الميكانيكية للخرسانة العالية الاداء المسلحة بألالياف

Authors: Wasan Ismail Khalil --- Ikbal Naeem Gorgis --- Zeinab Raad Mahdi
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2013 Volume: 31 Issue: 7 Part (A) Engineering Pages: 1365-1387
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

An experimental work was carried out to produce high performance concrete (HPC) using superplasticizer and silica fume reinforced with fiber. The variables studied were fibers type (steel fibers and polypropylene fibers), aspect ratio of steel fibers (60 and 100) and fiber volume fraction (0.0%, 0.5%, and 0.75%). The effect of fibers on the mechanical properties (compressive strength, splitting tensile and flexural strength, static modulus of elasticity, toughness, and resilience) of normal strength and high performance concrete was also studied. The results show that the optimum dosage of silica fume is 5% as addition by weight of cement with superplasticizer dosage 2 liter/100kg of cement. This dosage of silica fume improves the compressive strength of concrete by about 25% relative to concrete mix without silica fume. The addition of steel fibers causes a slight increase in compressive strength of HPC as fiber volume fraction increases, while the compressive strength decreases as fiber aspect ratio increases. Both splitting tensile and flexural strengths show a significant increase as the fiber volume fraction and aspect ratio increases. The percentage increase in compressive, splitting tensile and flexural strengths for HPC with steel fiber volume fraction 0.75% and aspect ratio 100 at age 60 days is about 9%, 75%, 64%, while for HPC containing polypropylene fiber with volume fraction 0.5% is about 8.5%, 2%, 0% respectively relative to non fibrous HPC.

يشمل البحث دراسة الخواص الميكانيكية للخرسانة العالية الاداء المسلحة بألالياف. يتضمن البرنامج العملي انتاج خرسانة عالية الاداء بأستخدام الملدن المتفوق وابخرة السيلكا المكثفة والمسلحة بالالياف. المتغيرات التي تم دراستها هي نوع الالياف (الالياف الفولاذية والياف البولي بروبلين) , النسبة الباعية للالياف الفولاذية (60, 100) والنسبة الحجمية للالياف (0%, 0,5%, 0,75%). تم دراسة تأثير اضافة الالياف على الخواص الميكانيكية (مقاومة الانضغاط, مقاومة الشد الانشطاري, مقاومة الانثناء, معامل المرونة الستاتيكي, الصلابة, الرجوعية) للخرسانة الاعتيادية والعالية الاداء. اظهرت النتائج ان الوزمة المثالية لابخرة السيلكا المكثفة كانت 5% كأضافة من وزن الاسمنت والوزمة المثالية للملدن المتفوق هي 2لتر لكل 100 كغم من الاسمنت . الوزمة لابخرة السيلكا المكثفة ساعدت في تطوير مقاومة الانضغاط للخرسانة حوالي 25% بالمقارنة مع الخلطة الخرسانة بدون ابخرة السيلكا.بينت النتائج ان اضافة الالياف الفولاذية تسبب زيادة طفيفة في مقاومة الانضغاط للخرسانة عالية الاداء عند زيادة النسبة الحجمية للالياف, بينما تقل مقاومة الانضغاط بزيادة النسبة الباعية للالياف. كذلك تبين بأن مقاومة الشد الانشطاري ومقاومة الانثناء تزداد بشكل واضح بزيادة النسبة الحجمية والنسبة الباعية للالياف. حيث كانت نسبة الزيادة في مقاومةالانضغاط والشد الانشطاري ومقاومة الانثناء للخرسانة عالية الاداء الحاوية على نسبة حجمية 0,75% ونسبة باعية 100 بعمر 60 يوم حوالي 9% و 75% و 64% اما بالنسبة للخرسانة عالية الاداء الحاوية على الياف البولي بروبلين بنسبة حجمية 0,5% فكانت نسبة الزيادة 8,5%و2% و0% على التوالي بالمقارنة مع الخرسانة عالية الاداءغير حاوية على الياف.


Article
The effect of addition of untreated and oxygen plasma treated polypropylene fibers on some properties of heat cured acrylic resin

Authors: Waffaa I. Mohammed --- Intisar J. Ismail
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2013 Volume: 25 Issue: 4 Pages: 33-38
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: The polymethyl methacrylate is the most reliable material for the construction of complete and partialdentures, despite satisfying esthetic demand itsuffered from having unsatisfactory properties like impact strength andtransverse strength.This study was designed to improve the impact strength and transverse strength of heat cure acrylic resin by addinguntreated and oxygen plasma treated polypropylene fibers and investigate the effect of this additive on someproperties of acrylic resin materials.Materials and methods: Untreated and oxygen plasma treated polypropylene fibers was added to PMMA powderby weight 2.5 %. Specimens were constructed and divided into 5 groups according to the using tests; each groupwas subdivided in to 3 subgroups. The tests conducted were impact strength, transverse strength, surface hardness,surface roughness, water sorption and solubility. Data were analyzed by one way analysis of variance (ANOVA) andleast significant differences (LSD).Results: After incorporation of untreated and oxygen plasma treated polypropylene fibers there was a highlysignificant increase in impact strength and surface hardness; while there was a non significant difference intransverse strength. Also the value of water sorption increase significantly but with the limit of ADA specification.Conclusion:Within the limit of this study it can be concluded that the reinforcement with polypropylene fiberseffective method to increase fracture resistance of denture base; while reinforcement with oxygen plasma treatedpolypropylene fibers further increase fracture resistance


Article
Influence of Poypropylene Fibers on the Soil Stabilization
تأثير ألياف البولي بروبلين على تثبيت التربة

Author: Heba Dawood Salim
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2013 Volume: 31 Issue: 20 Part (A) Engineering Pages: 316-323
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

In this paper the polypropylene fiber was chosen as the additive material to know how it is effect on the soil stabilization, which it is used as additive for concret mixture; the polypropylene fiber is inert material and does not interact with water. The paper studies the addition of this material to a silty clay soil and its effect on the consistency limits, shear strength and compaction of the blended materials. The results show that there is an improvement in the shear strength only when the addition of the rate 1% and 2%from soil weight; either the effective of the consistency limit it was increasing the water content with increasing the rate of the addition material, because it have drink of water. At the compaction test it was founded that the increasing in dry density at the addition of 1% and 2% and reducing its value at the addition of 3% with increasing of water optimization.

في هذا البحث، تم اختيار ألياف البولي بروبيلين كمادة مضافة لمعرفة تأثيره على تأثير على تثبيت التربة، والتي تستخدم كمضاف لخليط الخرسانة، وألياف البولي بروبلين هي مادة خاملة لا تتفاعل مع الماء. يدرس البحث إضافة هذه المادة إلى التربة الطينية الغرينية وأثرها على حدود القوام، قوة القص والرص للمواد المخلوطة. وتظهر النتائج أن هناك تحسنا في قوة القص فقط عند إضافة نسبة 1٪ و 2٪ من وزن التربة؛ إما حدود القوام الفعالة تعمل على زيادة محتوى الماء مع زيادة نسبة المواد بسبب شرب الماء. في اختبار الرص، وجدت زيادة في الكثافة الجافة عند إضافة 1٪ و 2٪ و تقل قيمتها عند إضافة 3٪ مع الزيادة المثلى للمياه.


Article
The Effect of Incorporation of Two Different Fibers on Some Mechanical Properties of Heat Cure Acrylic Resin Dr. Abdalbasit A Fatihallah BDS, MSc, PhD

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Abstract

To evaluate the effect of addition of different fibers on some mechanicalproperties of heat cured acrylic resin (flexural strength, impact strength and hardness).210 specimens were used in the study.70 specimens were used for flexuralstrength with measurements (65mm*10mm*2.5mm) length, width and thicknessrespectively. The specimens were divided into seven test groups (n=10). The firstgroup is the Control one and it was without fiber reinforcement, second groupreinforced with 2mm polyester fibers, third group reinforced with 4mm polyesterfibers, fourth group reinforced with 2mm Polypropylene fibers, fifth group reinforcedwith 4mm Polypropylene fibers, sixth group reinforced with 2mm of both fibers(polyester and Polypropylene), and seventh group reinforced with 4mm of both fibers(polyester and Polypropylene). 70 specimens were used for impact strength in sevengroup (n=10) with measurements (80mm*10mm*4mm) length, width and thicknessrespectively. 70 specimens were used for hardness test in seven groups (n=10) withmeasurements (65mm*10mm*2.5mm) length, width and thickness respectively.The Results Show that there are highly significant differences between all groupsexcept for a significant differences between control and combination 2 mm fiberlength (mean differences=33.45). For the hardness test the comparisons show thatthere is no significant differences between groups except for a significant differencesbetween control and combination of both fibers with 2mm length (mean differences=-1.34). For impact strength; there are highly significant differences between all groupsexcept for a significant differences between Polyester fiber of 2mm length andcombination of the two fiber of 2 mm length (mean differences=-3.1).In conclusion, the addition of different fibers (polyester and Polypropylene) toacrylic resin gives it more resistance to break and more resistance to bend.


Article
Evaluation of the Effect of silanized Zirconium Oxide nano-fillers and Plasma Treated polypropylene fibers Addition on some Properties of Heat Cured Acrylic Resin Denture Base Material

Author: Dr. Noor Falah Abdul-Hadi, B.D.S., M.Sc. * د.نور فلاح عبدالهادي
Journal: MUSTANSIRIA DENTAL JOURNAL مجلة المستنصرية لطب الاسنان ISSN: 18138500 Year: 2016 Volume: 13 Issue: 1 Pages: 70-76
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

Background: The polymethylmethacrylate is the most reliable material for theconstruction of dentures but it has the disadvantages of lacking strength andradio-opacity. The purpose of this study was to evaluate the effect of addition ofmodified nano-zirconium oxide (zro2 ) and plasma treated polypropylene fiberson some mechanical properties of heat cure acrylic resin materials.Materials and methods:- Zirconium oxide nanoparticles were coated with a layer ofpropyltrioxysilane before dispersed and sonicated in monomer(MMA)inpercentage of 2% by weight . The plasma treated polypropylene fibers were inpercentage of 2% by weight added to polymer powder. Sixty specimens wereconstructed and divided into 3 groups according to the using tests; each groupwas subdivided into two subgroups. The tests used were impact strength,transverse strength and surface hardness. Data were analyzed T-test.Results:- After the addition of plasma treated polypropylene fibers and modifiednano-Zro2 fillers there was a highly significant increase in impact strength,transverse strength and surface hardness.Conclusion: It can be concluded that the addition of modified nano-Zro2 fillers andplasma treated polypropylene fibers effective method to enhance the fractureresistance of acrylic denture base material.


Article
Studying the effect of addition a composite of silanized Nano-Al2O3 and plasma treated polypropylene fibers on some physical and mechanical properties of heat cured PMMA denture base material

Authors: Omar R. Muklif --- Intisar J. Ismail انتصار جميل اسماعيل
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2015 Volume: 27 Issue: 3 Pages: 22-27
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Polymethyl methacrylate (PMMA) is the most commonly used material in denture fabrication. Thematerial is far from ideal in fulfilling the mechanical requirements, like low impact and transverse strength, poorthermal conductivity. The purpose of this study was to evaluate the effect of addition a composite of surface treatedNano Aluminum oxide (Al2O3) filler and plasma treated polypropylene fiber (PP) on some properties of denture basematerial.Materials and methods: One hundred fifty prepared specimens were divided into 5 groups according to the tests,each group consisted of 30 specimens and these were subdivided into 3 groups (unreinforced heat cured acrylicresin as control group),reinforced acrylic resin with( 0.5%wt Nano Al2O3 and2.5%wt plasma treated PP fibers) groupand reinforced acrylic with(1%wt Nano Al2O3 and 2.5%wt plasma treated PP fibers group).The tests were impactstrength, transverse strength, indentation hardness(shore D), surface roughness thermal conductivity. The results werestatistically analyzed using ANOVA test.Results: A highly significant increase in impact strength, surface hardness, thermal conductivity with the addition of0.5%wt. (Al2O3) and 2.5%wt PP fiber to(PMMA),also there is a significant increase in surface roughness and nonsignificant increase in transverse strength. At the concentration of 1%wt nano (Al2O3)and 2.5%wt PP fiber there is ahighly significant increase in impact strength surface hardness and thermal conductivity. Non-significant differenceswere shown in transverse strength and significant increase in surface roughness.Conclusion: The addition of a composite of Al2O3 nanoparticles and PP fiber to PMMA improves the impact strength,surface hardness and thermal properties, surface roughness while non-significant difference in transverse strength


Article
EVALUATION OF MECHANICAL PROPERTIES OF HIGH PERFORMANCE SELF-CONSOLIDATED CONCRETE ENHANCED BY DISCRETE STEEL AND POLYPROPYLENE FIBERS
تقييم الخواص الميكانيكية للخرسانة عالية الأداء الذاتية الرص المعززة بالألياف الحديدية المنفصلة وألياف البولي بروبلين

Author: Ali Adel Abdulhameed
Journal: Journal of Engineering and Sustainable Development مجلة الهندسة والتنمية المستدامة ISSN: 25200917 Year: 2016 Volume: 20 Issue: 4 Pages: 34-52
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

High performance self-consolidating concrete HP-SCC is one of the most complex types of concrete which have the capacity to consolidated under its own weight, have excellent homogeneity and high durability. This study aims to focus on the possibility of using industrial by-products like Silica fumes SF in the preparation of HP-SCC enhanced with discrete steel fibers (DSF) and monofilament polypropylene fibers (PPF). From experimental results, it was found that using DSF with volume fraction of 0.50 %; a highly improvements were gained in the mechanical properties of HP-SCC. The compressive strength, splitting tensile strength, flexural strength and elastic modulus improved about 65.7 %, 70.5 %, 41.7 % and 80.3 % at 28 days age, respectively with retaining the main properties of HP-SCC. Furthermore, using PPF with volume fraction up to 0.10 %; an enhancement in the compressive and elastic modulus of HP-SCC about 47.4 % and 31 % was obtained at age of 28 days, respectively. Moreover, using PPF with volume fraction of 0.15 %, the splitting tensile strength and flexural strength of HP-SCC improved about 44.5 % and 20.3 %, respectively.

تعتبر الخرسانة العالية الأداء والذاتية الرص واحدة من أعقد أنواع الخرسانة التي لها القابلية على الرص تحت تأثير وزنها الذاتي فضلاً عن تجانسها الممتاز وديمومتها العالية. هذه الدراسة العملية تهدف إلى إستخدام أبخرة السليكا كمنتج صناعي ثانوي في إنتاج الخرسانة عالية الأداء والذاتية الرص والمعززة بألياف حديدية منفصلة وألياف البولي بروبلين أحادية الشعيرة. بينت نتائج الفحوصات العملية، إن أستخدام الألياف الحديدية المنفصلة بنسبة 0.5 % من حجم الخرسانة أدى إلى تحسن عالي في الخواص الميكانيكية لها حيث زادت كل من مقاومة الأنضغاط ، مقاومة إنفلاق الشد، مقاومة الإنثناء و معامل المرونة بنسبة 65.7 % ، 70.5 % ، 41.7 % ، 80.3 % وعلى الترتيب لمعدل النماذج الخرسانية المختلفة وبعمر 28 يوماً. علاوة على ذلك، إن أستخدام ألياف البولي بروبلين أحادية الشعيرة بنسبة لاتتجاوز 0.10 % من حجم الخرسانة أدى إلى زيادة مقاومة الأنضغاط ومعامل المرونة للخرسانة عالية الأداء والذاتية الرص بنسبة 47.4 % ، 31 % بعمر 28 يوماً، على الترتيب. أيضاً، إن أستخدام الألياف الأخيرة بنسبة حجمية مقدارها 0.15 % أدى إلى تحسن مقاومة إنفلاق الشد ومقاومة الإنثناء للخرسانة وبعمر 28 يوماً لمعدل النماذج الخرسانية المختلفة بنسبة 44.5 % ، 20.3 %، على الترتيب.


Article
Imrovement Of Structural Properties For Reinforced Concrete Deep Beam Using Silica Fume With Polypropylene Fibers
تحسين الخصائص الانشائية للعتبات الخرسانية المسلحة العميقة الحاوية على غبار السليكا بلأضافة الى الياف البولي بروبلين

Author: Rafid Saeed Atea
Journal: Muthanna Journal of Engineering and Technology(MJET) مجلة المثنى للهندسة والتكنولوجيا ISSN: 25720317 25720325 Year: 2017 Volume: 5 Issue: 1 Pages: 1-9
Publisher: Al-Muthanna University جامعة المثنى

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Abstract

The objective of this study is to investigate the effect of silica fume and polypropylene fibers to gather on the mechanical properties of concrete and the improvement on general behaviour for deep reinforced concrete beams containing silica fume and polypropylene fibers. Properties studied include Silica fume content used was (0%, 10% and 20%) by replacement of equal weight of cement in concrete. Polypropylene fibers were added in (0%, 0.20% and 0.40%) by volume fraction of concrete. Totally three deep reinforced concrete beams specimens with cross-sectional dimension of (100X300)mmfor a length of 1000mm were tested. Out of which three beams provisional on the relation of shear span (a) to the active depth (d) .The (a/d) ratio was used (1) with different containing silica fume and polypropylene fibers with differents percentsge of replacement for silica fume and various Polypropylene fibers were addition from volume fraction.The experimental test results improved for toughened properties contain the compressive strength, splitting tensile strength and modulus of elasticity and also enhancement general behaviour for deep reinforced concrete beams when studied the crack patteren, load-deflection and strains.

أن الهدف من هذا البحث هو دراسة تأثير غبار السليكا و الياف البولي بروبلين سوية على الخواص المتصلبة للخرسانة وايضا دراسة التاثير على سلوك العتبات الخرسانية المسلحة العميقة الحاوية على غبار السليكا و الياف البولي بروبلين . الخصائص التي درست تضمنت أستعمال غبار السليكا بنسب 0%,10%و20% على التوالي, وايضا اضافة بنفس الوقت الياف البولي بروبلين بنسب حجمية 0%و200.%و400.% , حيث تم دراسة ثلاث عتبات مسلحة عميقة بمقطع داخلي(300X100)ملم وطول1000ملم تم اختبارهن ,بلأعتماد على نسبة فضاء القص(a) الى العمق الفعّال ,(d)حيث نسب(a/d) استخدمت وهي(1), من خلال الفحص العملي للخواص المتصلبة للخرسانة بينت تحسن في الخصائص وايضا بينت الدراسة تحسن في سلوك العتبات الخرسانية المسلحة العميقة الحاوية على غبار السيليكا و الياف البولي بروبلين من خلال النتائج المختبرية من عرض التشقق و فحص القوة-الهطول وايضا فحص الأنفعال مقارنة للعتبة غير حاوية على غبار السليكا و الياف البولي بروبلين .

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