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Article
The Effect of Formaldehyde Disinfectant on Compressive Strength of Dental Stone (Type IV)

Authors: Musab Mohamed Ibrahim --- Munther Najeeb Kazanji --- Salwa Hachim Mohammed
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2016 Volume: 16 Issue: 1 Pages: 1-9
Publisher: Mosul University جامعة الموصل

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Abstract

Aims: The purpose of this study is to evaluate the effect of 2% formaldehyde on compressive strength of dental stone (type IV), and to evaluate its antibacterial effect. Materials and methods: To study the effect of 2% formaldehyde on compressive strength of dental stone (type IV), ten samples of stone were prepared in cylindrical blocks and divided into two groups, each group contain of (5) samples. First group composed of stone and distilled water as (control group) and the second group composed of stone and (2%) formaldehyde solution. after (1h) the samples were tested for compressive strength using digital compression machine(ALFA Company, Turkey).To study the bacterial effect of formaldehyde 60 stone discs prepared and mixed with formaldehyde 2% divided into 12 group (each group consist of 5 discs) and stored for different intervals between 1-12 days, antibacterial effect against salivary sample for each interval day using disc diffusion test. Results: The statistical analysis of data by analysis of t-test reveals significant different in compressive strength between control group and stone-2% formaldehyde group at (P<0.05). The result showed that second group which contains 2%formaldehydehad higher values compared with control group. Also the results showed that the antibacterial effect of stone-formaldehyde discs continued till 12thday. Conclusions: Adding 2% formaldehyde as chemical disinfectant to dental stone increase the compressive strength in addition of the antibacterial activity of stone - formaldehyde disc continued till 12th day.


Article
Compressive strength measurement for cement replacement with recycled glass in concrete
قياس قوة الانضغاط للسمنت المبدل بالزجاج المعاد تدويره في الخرسانة

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Abstract

The most important environmental constraints at the present time is the accumulation of glass waste (transparent glass bottles). A lot of experiments and research have been made on waste and recycling glass to get use it as much as possible. This research using recyclingof locally waste colorless glass to turn them into raw materials as alternative of certain percentages of cement to save the environment from glass waste and reduce some of the disadvantages of cement with conserving the mechanical and physical properties of concrete made.A set of required samples were prepared for mechanical test with different weight percentage of waste glass(2%, 4%, 5%, 6%, 8%, 10%, 15%, 20% and25%). American standard for calibration (ASTM C109 / C109M-02) to measure the compressive strength where the results showed that the Maximum compressive strength wasobtained at the low weight percentage replacement 2%, 4% and 5% 6% which is 67.12, 69.24, 62.56 and59.96 Mpa respectively. for originally mix recorded bending resistance (54.16) Mpa.

ان اهم المعوقات البيئية في وقتنا الحاضر هي تكدس النفايات الزجاجية (القناني الزجاجية الشفافة) وهناك عدة بحوث وتجارب اجريت عل النفايات لمحاولة تدويرها للاستفادة منها قدر المستطاع, هذا البحث يتضمن دراسة اعادة تدوير النفايات الزجاجية وتحويلها الى مواد اولية بديلة عن السمنت لتخليص البيئة من النفايات الزجاجية وتقليل بعض السلبيات الناتجة من استخدامات السمنت وتفاعلاته والمحافظة عل الخواص الميكانيكية والفيزيائية للخرسانة.حيث تضمنت هذه الدراسة اعادة تدوير القناني الزجاجية الشفافة المحلية الاستخدام وتحويلها الى مسحوق ناعم وتبديله بنسب معينة من السمنت. تم تحضير مجموعة من النماذج المطلوبة للفحوصات الميكانيكية (مقاومة الانحناء) وبمعدل عشرة نماذج لنسب وزنية مختلفة هي (2%,4%,5%,6%,8%,10%,15%,20%,25%). تم استخدام فحص الانضغاط لحساب اعلى مقاومة انضغاط (compressive test) للنسب الوزنية السابقة حسب المواصفة الامريكية للمعايرة القياسية (ASTM (C109/C109M-02 وبينت النتائج ان النماذج) 2, 4, 5, 6) ذات النسب الوزنية القليلة سجلت نتائج تحمل قوة الانضغاط هي(67.12, 69.24, 62.56, 59.96)على التوالي مقاربة للعينات الأصلية مبينة بذلك ان النسب الوزنية القليلة افضل من النسب الوزنية العالية مقارنة بالنسبة الاصلية حيث سجلت نتيجة Mpa(54.16).


Article
The Effects of Lime Addition and Fineness of Grinded Clinker on Properties of Portland Cement

Authors: Nadia S. Ismael --- Mostafa N. Ghanim
Journal: Tikrit Journal of Engineering Sciences مجلة تكريت للعلوم الهندسية ISSN: 1813162X 23127589 Year: 2016 Volume: 23 Issue: 2 Pages: 86-95
Publisher: Tikrit University جامعة تكريت

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Abstract

Two types of Portland Cement Clinker "PCC" were used in this study: high fineness grinded and low fineness grinded , and after grinding of PCC, hydrated lime was used in 5%,10% and 15%; by weight, as a replacement of the blend cement with a constant 3% addition of gypsum by the blend weight. The importance of this study is to show the influences of different fineness on the physical properties of the blended cement, and to find the probability of using hydrated lime (that could be a by-product) in cement and declare its effects on the blend, so the solid waste "lime" and air pollutant of cement factories will reduce. In this research, the low fineness blend exhibited about 87% from compressive strength of high fineness blend at 28 days age. The results show that the using of hydrated lime up to 10%; by weight, as a replacement of cement will give good compressive strength and workability, and will reduce moderately the setting time, but the use of hydrated lime by more than 10% will reduce the compressive strength and increase the unsoundness of the blend (from 3mm expansion at 10% hydrated lime to 29mm expansion at 15% hydrated lime).


Article
EFFECT OF RC AND SBR AS COATING CURING MATERIALS ON PROPERTIES OF HIGHWAY RIGID CONCRETE PAVEMENT
تاثير RC و SBR كمواد تغطية انضاج على خواص خرسانة بلطات الطرق الجاسئة

Authors: Shakir Al-Busaltan شاكر البو سلطان --- Ma'aly Al-Ani معالي العاني --- Ola Al-Jawad علا الجواد
Journal: Al-Qadisiyah Journal for Engineering Sciences مجلة القادسية للعلوم الهندسية ISSN: 19984456 Year: 2016 Volume: 9 Issue: 1 Pages: 47-58
Publisher: Al-Qadisiyah University جامعة القادسية

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Abstract

The surface to volume ratio of concrete pavement is large, also, due to hot climate of Iraq, coating concrete pavement after casting is essential to ensure vital curing, consequently to obtain significant engineering properties. This research work reports the results of a study performed to evaluate the engineering properties of concrete coated with concrete surface coatings solutions; two types of coating were used representing co-polymer (Styrene-Butadiene Rubber, SBR) and by-product material (Residue Crude, RC). Different coating solutions were prepared from these solutions, individually and collectively; i.e. 100% SBR, 75% SBR+25% RC, 50% SBR+50% RC, 25%SBR+ 75%RC, and 100%RC. The engineering properties of the uncoated and coated concrete samples were evaluated by assessing compressive strength, flexure strength and hardness for concrete convenience for highway rigid pavement. The compressive strength was evaluated for the specimens at 7, 14, 28 and 90 days, where flexure and hardness were evaluated at 28days. The results showed that the coated samples with both SBR and RC performed noticeably better in contrast with uncoated samples under air-dry conditions. Additionally, obvious differences in the performance of the collective solutions were recognized. From the results, however, local by-product materials have been proven as a significant coating materials suitable to enhance the concrete used for pavement purposes.

من الملاحظ ان نسبة السطح الى الحجم في الخرسانة المستخدمة للطرق عالية, كذلك بسبب الجو الحار في العراق, يكون تغطية الخرسانة بعد عملية الصب مهمة لضمان انضاج فعال, و بالتالي الحصول على خواص هندسية عالية. يقر هذا البحث نتائج دراسة تقيم خرسانة مغطاة سطحيا بمحاليل. وهذا المحاليل هي مادة الستارين بيوتدين ستارين SBR ( مادة بولمراتية), ومادة ناتج عرضي من الصناعة النفطية هي رواسب الخام RC. عدة محاليل تغطية تم تحضيرها من هذين المحلولين بشكل مفرد او بخليط منهما: 100% SBR, 75% SBR+25% RC, 50% SBR+50% RC, 25%SBR+ 75%RC, 100%RC. تم تقيم الخواص الهندسية لنماذج الخرسانة المغطاة و غير المغطاة بمقاومة الانضغاط, مقاومة الكسر و الصلابة وبالطبع وفق متطلبات الخرسانة المستخدمة للبلاطات الجاسئة . وتم تقيم النماذج لمقاومة الانضغاط باعمار 7,14, 28, 90 يوم, بينما نماذج مقاومة الكسر و الصلابة باعمار 28 يوم.وبينت النتائج زيادة ملحوظة في اداء الخرسانة المغطاة بال RC و SBR بالمقارنة مع الخرسانة المتروكة بدون تغطية تحت تأثير حرارة الجو. كما ان هناك فروقات ملحوظة ايضا في نتائج الاداء حسب نوع المحلول المستخدم. وكنتيجة ملموسة تم اثبات فعالية مادة ناتجة عرضيا من الصناعة المحلية في تحسين اداء الخرسانة المستخدمة في البلاطات الجاسئة كمادة تغطية للانضاج.


Article
Influence of Incorporating Construction Building Demolition as Recycled Aggregate on Concrete Behavior
تأثير اضافة بعض مخلفات الابنية الانشائية المهدمة كركام معاد تدويره على سلوك الخرسانة

Author: Shatha Sadiq Hussen
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2016 Volume: 34 Issue: 1 Part (A) Engineering Pages: 33-49
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

Because of increasing waste production and public concerns about the environment, it is desirable to recycle materials from construction and building demolition. This study aimed to find a technique for producing recycled aggregate concrete obtained from construction and building demolition waste. Laboratory trials were conducted to investigate the possibility of using recycled aggregate from different sources in Iraq, as a partial replacement of both coarse and fine natural aggregates or one of them. Recycled aggregate consists of crushed concrete (CC) or acombination of crushed brick (CB) and crushed concrete (CC). The aggregate in concrete was replaced with 10%, 20%, 30% and 50% by weight of crushedconcrete (CC) or crushed brick (CB) and crushed concrete CC. Some of mechanical properties of recycled aggregate concrete as compared to those of conventional normal aggregate concrete are studied. Compressive strength and the splitting tensile strength were determined after curing for 7, 28, and 90 days while density was determined after28 days.From these results, it is reasonable to assume that the use of recycled concrete aggregate does not jeopardize the mechanical properties of concretefor replacement ratios up to 50%. The concrete prepared with the crushed concrete only as a partial replacement of natural aggregate achieved the highest strength values at 7, 28and 90 days. The results suggested that an aggregate that contains 50% recycled aggregate is optimum for producing recycled aggregate concrete The test results showed that the replacement of coarse or fine natural aggregate by recycled brick aggregate at the levels of 10,20,30 and 50% had little effect on the compressive strength of the specimens.

بسبب زيادة إنتاج النفايات والمخاوف العامة حول البيئة فانه من المستحسن إعادة تدوير بعض المواد من الابنية و المنشات المهدمة. تهدف الدراسة إلى ايجاد تقنية الهدف هو انتاج ركام يصلح للخرسانةلإنتاج خرسانةالركام المعاد تدويره والتي نحصل عليها من مخلفات الابنية و المنشات المهدمة. أجريت التجارب المختبرية لفحص إمكانية استخدام الركام المعاد تدويره من مصادر مختلفة في العراق، كنسبة تعويضية من كل من الركام الطبيعي الخشن والناعم أو احدهما.يتالف الركام المعاد تدويره من الخرسانة المسحوقة أو خليط من الطابوق المسحوق والخرسانةالمسحوقة. تم استبدال الركام الطبيعي في الخرسانة جزئيا بنسبة وزنية 10٪، 20٪، 30٪ و 50% منالخرسانة المسحوقةأو من الطابوق المسحوق والخرسانةالمسحوقة.تم دراسة بعض الخواص الميكانيكية لخرسانة الركام المعاد تدويره بالمقارنة مع الخرسانة الاعتياديةذات الركام الطبيعي . تم تحديد مقاومة الانضغاط ومقاومة الشد بالانشطاربعد المعالجةبالماء لمدة 7، 28، و 90 يوما وتمتحديدالكثافة بعمر28 يوم.بينت النتائج بأنه يمكن استخدامركامالخرسانة المعاد تدويرها بما لا يعرض الخواص الميكانيكية للخرسانة للخطر لنسب استبدال تصل الى 50٪. الخرسانةالمحضرة من الخرسانة المسحوقة فقط كتعويض جزئي من الركام الطبيعي حققت أعلى قيمةللمقاومة بعمر 7، و 28 و 90 يوما. وتشير النتائج أن الركام الذي يحتوي50٪من الركام المعاد تدويره هو الأمثل لإنتاج خرسانة الركام المعاد تدويره . وأظهرت نتائج الاختبار أن استبدال الركام الطبيعي الخشن أو الناعمبركام الطابوق المعاد تدويره وبنسبة استبدال 10،20،30 و 50٪ كان تأثيرهاقليل على مقاومة الانضغاط للنماذج.


Article
Pozzolanic Activity and Compressive Strength of Concrete Incorporated nano/micro Silica
الفعالية البوزولانية و مقاومة انضغاط الخرسانة الحاوية على نانو/مايكرو سليكا

Authors: Maan S. Hassan --- Shakir A. Salih --- Mohammed S.Nasr
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2016 Volume: 34 Issue: 3 Part (A) Engineering Pages: 483-496
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

This paper aims to give a recommendation about the suitable nano silica proportion and curing method for testing its strength pozzolonic activity, in addition to suggest a mixing or batching procedure of this material with other concrete ingredients. Theinfluence of nanoand micro silicaon concrete compressive strength is also studied. Three proportions of nano silica (0.5, 5, &10%) , two curing methods (accelerated in oven and normal in water) and two tested agesare used in pozzolonic activity test of nano silica. For compressive strength test, eleven mixes are considered:without-adding (two mixes), three micro silica (M) mixes with replacement ratios of 5, 10 & 15%, four nano silica (N) mixeswith replacement ratiosof 0.5,1.5, 3 & 5%, and three micro plus nano silica mixes (0.5N+9.5M,1.5N+8.5M and 3N+7M%) are adopted.Results of pozzolanic activity test denoted that nano silica has remarkable pozzolanic activity for all tested replacements.However, it is suggest using 5% nano silica for performing this testby usingeither accelerated or water curing. Additionally, it was found that nano silica had more impact on compressive strength of concrete than micro silica for all tested ages.Where, maximum enhancement ratios of compressive strength were about 33% and 27% for 3% nano silica mix at 7 and 90 days age respectively, and 22% for 5% nano silica mix at 28 days age. For micro silica mixes, higher improvement ratios were found in 15% micro silica mix: 2%,5%&7% at 7,28 &90 days age respectively.

يهدف هذا البحثلإعطاء توصية حول نسبة النانو سليكا وطريقة الانضاج المناسبة لفحص قوة فعاليتها البوزولانية, بالإضافة الى اقتراح طريقة لخلط او مزج هذه المادة مع مكونات الخرسانة الاخرى. كما تم دراسة تاثير تضمين النانو والمايكرو سليكا على مقاومة انضغاط الخرسانة. لفحص الفعالية البوزولانية للنانو سليكا، تم اعتماد ثلاث نسب تعويض (0.5, 5, 10%)،طريقتي انضاج ( معجل في الفرن واعتيادي في الماء)و عمري فحص. تم اعتماد احد عشر نوعا من الخلطات الخرسانية في فحص مقاومة الانضغاط، خلطتان بدون أي اضافة و ثلاث خلطات للمايكرو سليكا (M) بنسب تعويضية 5, 10, 15% و اربع خلطات للنانو سليكا (N) بنسب تعويضية 0.5, 1.5, 3, 5% , وثلاث خلطات للنانو مع المايكرو سليكا (0.5N+9.5M, 1.5N+8.5M و3N+7M%). اظهرت نتائج فحص الفعالية البوزولانية بان النانو سليكا تمتلك فعالية بوزولانية معتد بها لجميع النسب المفحوصة, مع ذلك،تم التوصيةباعتماد نسبة 5% نانو سليكا لتنفيذهذا الفحص باستخدام اما انضاج معجل او بالماء. اضافة لذلك, لقد وجد بان النانو سليكا ذاتتأثير كبير على مقاومة انضغاط الخرسانة مقارنة بالمايكرو سليكا ولجميع الاعمار المفحوصة. حيث ان اعلى نسب تحسين لمقاومة الانضغاط كانت تقريبا 33% و 27% لخلطة 3% نانو سليكا في الاعمار 7 و90 يوم على التوالي، و 22% للخلطة 5% نانو سليكا في عمر 28 يوم. بالنسبة لخلطات المايكرو سليكا، فان اعلى نسبة تحسين وجدت في خلطة 15% مايكرو سليكا: 2%، 5% و 7% في الاعمار 7، 28 و 90 يوم على التوالي.


Article
Effect of Using Plastic and Rubber Wastes as Fine Aggregate on Some Properties of Cement Mortar

Authors: Basil S. Al-Shathr --- Iqbal N. Gorgis --- Rafid F. Motlog
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2016 Volume: 34 Issue: 8 Part (A) Engineering Pages: 1688-1699
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

This research describes the production of lightweight cement mortar using four types of fine aggregates including chopped rubber tires, chopped plastic wastes, a mixture from the previous types by 1:1, and a mixture composed from substitution of 10% from the previous type by natural sand. Theuseofthese wastes has rolein getting rid oftheir hugequantitieswhich constitute a fundamentalenvironmental problembecause of the difficulty of itsdegradation.Four, cement to aggregate ratios have been used. They are1:0.5, 1:0.7, 1:1, and 1:1.2 for each aggregate type mentioned above, with changing w/c ratio and superplasticizer content to have a constant flow of about 23%. Also, the effect of curing samples by different methods, including continuous submerge in water, autoclave curing for 3 hours, and carbonation curing by 50% and 100% CO2 at 75oC for 90 minutes, was studied.The results indicated that it is possible to produce lightweight cement mortar, using any type of aggregates mentioned above, with compressive strength satisfying the requirements of clay brick class C of Iraqi Standard, that used in partitions, for a mix proportion of 1:1, except when using chopped rubber tires that need using mix proportion of 1:0.5 to satisfy the strength requirements, where the use of this aggregate type needs higher w/c ratio and superplasticizer content to get the required flow, which leads to lower strength in comparison with the other types. As for chopped plastic aggregate, although it needs lower water and superplasticizer content to get the required flow and strength, care should be taken to balance betweenthe amount of waterand superplasticizer addedto avoidthe possibility of segregation in it. So it was found that using the mixture of chopped plastic and rubber aggregate give the best properties. Results also indicated that using all aggregate typeswith cement: aggregate mix proportion 1:1 satisfy the flexural strength requirements of American Standards for cellulosic fiber insulating boards, and were with thermal conductivity valueslower than that for brick and concrete having density lower than 2000 kg/m3. The results indicated that partial replacement of 10% mixed waste aggregates by normal sand cause increase in strength but in the same time increase density and thermal conductivity for the produced mortar.Results also indicated that curing by autoclave or curing with 50% or 100% CO2 cause increase in the 7 days strength compared with those cured by water but they show almost the same strength at 28 days age.


Article
A Comparative Study of Thermal Insulations and Physical Properties of Lightweight Concrete Using Some Raw Materials

Authors: Sanaa A. Hafid --- Amenah E. Mohammed Ridha
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2016 Volume: 34 Issue: 4 Part (B) Scientific Pages: 470-478
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

In this work, no-fine lightweight concrete was produced by using crushed bricks, thermostone as coarse aggregates to produce lightweight concrete. For both, superplasticizers were added to the mixture, the specimens were then cured in water for (7, 28, 60) days respectively.Compressive strength determine the mechanical properties, Physical properties of these concrete types were examined through thermal conductivity and fresh density. The compressive strength test showed that the compressive strength of the concrete was about (8-15.7) N/mm2 byusing natural gravel aggregate, (4.8-8.1) N/mm2 by using crushed bricks, and (3.14-5.4) N/mm2 by using thermostone aggregate. After 28 days, the thermal conductivity were (0.58),(0.41),(0.26) W/m.k, for the natural gravel ,crushed bricks and thermostone concrete.Besides; these concrete types are characterized by their low cost, environmentally friendly,high production rate, fire resistance, thermal insulation and light weight.


Article
Mechanical Properties of Self-Compacted Concrete

Authors: Ammar SaleemKhazaal --- Alyaa Abbas Ali --- Assim Mohammed Lateef
Journal: Tikrit Journal of Engineering Sciences مجلة تكريت للعلوم الهندسية ISSN: 1813162X 23127589 Year: 2016 Volume: 23 Issue: 1 Pages: 40-52
Publisher: Tikrit University جامعة تكريت

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In this research, trial mixes were conducted according to Self-Compacted Concrete (SCC) specifications, a mix that gave a higher compressive strength to the age of seven days has been selected. Then after selecting the appropriate mix, concrete samples had poured and were distributed into five groups; each group consists of six cubes, six cylinders, and six prisms. The samples of each group are testing for compressive, tensile splitting, and flexure strengths respectively for the ages of 7, 14, 28, 60, and 90 days respectively. Before of conduction of destructive tests, the samples were tested using ultrasonic waves to determine the relationship between the concrete strength and pulse velocity and in the same way for all ages in above. Experimental results showed that, all concrete mechanical properties have improved, and the maximum improve was in flexural strength followed by compressive strength and tensile splitting strength. The cube compressive strength increased according to (G1 at 7 days curing) from 34.3% to 71.8%, the percentage of increase of tensile strength according to (G1 at 7 days curing) from 16.8% to 64.3% , modulus of rupture increased according to (G1 at 7 days curing) from 34.6% to 98.7% for ages (14, 28, 60, 90 days) respectively. Pulls velocity increased according to (G1 at 7 days curing): For cube from 5.1% to 23.9%, for cylinder from 21.4% to 40.3%, for prisms from 7.1% to 29.2%.


Article
A COMPARISON BETWEEN AMERICAN AND BRITISH METHODS OF MIX DESIGN WITH SUGGESTIONS FOR IMPROVEMENT

Author: Dr. Adnan Flayih Hassan Al-Sibahy
Journal: Al-Qadisiyah Journal for Engineering Sciences مجلة القادسية للعلوم الهندسية ISSN: 19984456 Year: 2016 Volume: 9 Issue: 3 Pages: 423-441
Publisher: Al-Qadisiyah University جامعة القادسية

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Abstract

AbstractThis paper presents an analytical calculation and experimental investigation to evaluate the American and British methods usually used for mix design of normal concrete. Six concrete mixes with different target of mean strength were design using crushed and uncrushed aggregates. A reliable approach has been suggested to calculate the mix proportions. In order to validate the former approach, an experimental programme was running to measure the workability aspect and compressive strength of three selected concrete mixes designed for strength levels of 21.5 MPa, 27.5 MPa and 36.5 MPa at different sample ages using 108 cubes. The results obtained showed notable differences between the approaches of American and British methods adopted to calculate the mix proportions. There was no indication have found in the American method to distinct between design the concrete mix containing crushed aggregate and that of uncrushed aggregate. The procedure followed in British method produced concrete mix with higher strength than that designed according to American method. The experimental results of compressive strength and workability showed close agreement with the suggested approach for calculation the mix proportions.

الخلاصةيعرض هذا البحث حسابات تحليلية و تحريات مختبرية لتقييم الطريقتين الامريكية والبريطانية المعتمدة لتصميم الخلطة الخرسانية الاعتيادية. صُممت ستة خلطات خرسانية ذات مديات مختلفة من المقاومة بإستخدام الحصى المكسر بجانب وغير المكسر بجانب اخر. تم اقتراح إسلوب مقبول للحصول على نسب الخليط عند تصميم الخلطة بالطريقتين. ولاجل التاكد من صلاحية هذا الاسلوب تم اجراء برنامج عملي لقياس قابلية التشغيل ومقاومة الانضغاط لثلاث خلطات مختارة وبمقاومات تصميمة مقدارها 21.5 ميكاباسكال،27.5 ميكاباسكال و 36.5 ميكاباسكال وبأعمار مختلفة باستخدام 108 مكعب.أظهرت النتائج المستحصلة اختلاف ملحوظ بين المنهج المتبع في الطريقتين الامريكية والبريطانية لتحديد نسب الخليط. فالطريقة الامريكية لم تميز في التصميم بين طبيعة الركام المستخدم في الخرسانة سواء كان مكسر او غير مكسر. اما المنهج المتبع في الطريقة البريطانية فيميز بين طبيعة الركام المستخدم وينتج خرسانة ذات مقاومة انضغاط اعلى منها في الطريقة الامريكية. نتائج الفحوصات اظهرت توافق كبير بينها وبين المنهج المقترح لتعديل الحسابات الخاصة بتصميم الخلطة الخرسانية.

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