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Article
Finite Element Analysis of Reinforced Concrete T-Beams with Multiple Web Openings under Impact Loading
التحليل بإستخدام العناصر المحدده لعتبات خرسانيه مسلحه ذات مقطع (T) حاويه على فتحات وتره متعدده تحت تأثير الحمل الصدمي

Authors: Nazar Kamel Oukaili نزار كامل العقيلي --- Abeer Hussein Al-Shammari عبير حسين الشمري
Journal: Journal of Engineering مجلة الهندسة ISSN: 17264073 25203339 Year: 2014 Volume: 20 Issue: 6 Pages: 15-27
Publisher: Baghdad University جامعة بغداد

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Abstract

In this study, a three-dimensional finite element analysis using ANSYS 12.1 program had been employed to simulate simply supported reinforced concrete (RC) T-beams with multiple web circular openings subjected to an impact loading. Three design parameters were considered, including size, location and number of the web openings. Twelve models of simply supported RC T-beams were subjected to one point of transient (impact) loading at mid span. Beams were simulated and analysis results were obtained in terms of mid span deflection-time histories and compared with the results of the solid reference one. The maximum mid span deflection is an important index for evaluating damage levels of the RC beams subjected to impact loading. Three experimental T-beams were considered in this study for calibration of the program. All models had an identical cross-section and span similar to those of the experimental beams. The diameter of the openings of the experimental beams was 110 mm. Three other diameters were varied (50, 80 and 130) mm. The location of the face of the opening with respect to the location of impact loading was investigated (the face of the opening at distance varied 0d, 0.5d, 1d and 1.5d from the location of loading, where d is the effective depth) and the number of web openings was varied (2,4 and 6) openings. All modeled beams subjected to dropping mass of 24.5 kg with height of drop of 250 mm (as for the experimental beams). Results obtained from this study showed that the behavior of beams with circular openings of diameter equal to 22% the web depth has a small effect on the response of the RC T-beams. On the other hand, introducing circular openings with a diameter equal to 35% and 57% of the web depth (80 and 130 mm) increases the maximum mid span deflection by 23% and 43% respectively. Results also showed that, openings with a distance greater than or equal to 1.5 d from the location of impact loading have no effect on the deflection of the RC beams.

في هذه الدراسه تم عمل تحليل ثلاثي الأبعاد بإستخدام طريقة العناصر المحدده عن طريق البرنامج التحليلي ANSYS وذلك لتمثيل عتبات خرسانيه مسلحه ذات مقطع (T) تحتوي على فتحات وتره متعدده دائريه الشكل خاضعه لحمل صدمي. تم إعتماد ثلاث متغيرات تصميميه تضم: حجم وموقع و عدد الفتحات. تم تسليط الحمل الصدمي على 12 نموذج من العتبات الخرسانيه المسلحه بسيطة الإسناد في نقطه واحده تقع منتصف الفضاء. النتائج التي تم الحصول عليها والتي هي بدلالة مخططات هطول منتصف الفضاء مع الزمن تم مقارنتها مع نتائج النموذج المرجعي الغير حاوي على فتحات حيث إن الهطول الأقصى هو مؤشر مهم لتحديد مستوى الضرر للعتبات الخاضعه للحمل الصدمي. تم اعتماد نتائج ثلاث عتبات مفحوصه عمليا من أجل معايرة البرنامج. جميع النماذج لها مقطع وفضاء مماثل للعتبات المفحوصه عمليا. قطر فتحات العتبات المفحوصه عمليا يساوي 110ملم. ثلاثة أقطار أخرى تم دراستها (50، 80، 130 ملم) وكذلك تم دراسة موقع الفتحات نسبة الى موقع الحمل الصدمي (بداية الفتحه تتغير بمسافة 0d، 0.5d، 1d، 1.5d من موقع الحمل) وكذلك عدد الفتحات متغير (2، 4، 6 فتحات). النتائج المستحصله بينت أن العتبات ذات فتحات دائريه بقطر 22% من عمق الوتره لها تأثير قليل على هطولها. من ناحيه أخرى فإن عمل فتحات دائريه بقطر 35% و 57% من عمق الوتره يزيد من الهطول الأقصى لمنتصف الفضاء بنسبة 23% و 43% على التوالي. كذلك بينت النتائج بأن الفتحات ذات مسافه اكبر أو تساوي 1.5d من موقع الحمل الصدمي ليس لها تأثير على هطول العتبات الحاويه على تلك الفتحات.

Keywords

beams --- web openings --- impact loading


Article
Shear Lag in Reinforced Concrete T-Beams with Web Openings

Authors: Eyad Kadhum Sayhood --- Nisreen Saleh --- Ahmed S.Hanon
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2016 Volume: 34 Issue: 8 Part (A) Engineering Pages: 1673-1687
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

In this paper, an extensive study is carried out 18 beams on the behavior of T-beams (8 with web openings, 10 without openings). Compressive strains distribution at the flanged are investigated with the presence of the openings in web to recheck the effective width of flange with real flange width. Parametric study are considered in this paper includes the compressive strength, longitudinal flexuralreinforcement,flangereinforcement,shear reinforcement and theweb openings (location, shape, size). Generally, standard codes of practice have overestimated effective flange width due to concentrated load effect, and codes do not take into account the web openings effect. Based on the results, the enhancement in effective width for each parameter were 9.1%-13.36%(compressive strength),10.1%-13.3%(longitudinal flexural reinforcement),7.6%-18.2%(flange reinforcement),3.35%-5.7%(shear reinforcement), the web openings reduced the effective flange width by 15% (openings at mid span ) and 5% ( openings at quarter span ) and the circular opening gavean optimum effective width better than rectangular opening were located both at quarter span.


Article
Experimental and Numerical Investigation of High Strength Reinforced Concrete Deep Beams with Web Openings under Repeated Loading
التحقيقات التجريبية و العددية للعتبات الخرسانية المسلحة العميقة ذات الفتحات في وتراتها تحت تحميل المتكررة

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Abstract

This paper presents experimental investigations to study the behavior of High Strength Reinforced Concrete (HSRC) deep beams with web openings under monotonic and static repeated loading conditions. The experimental work procedure consisted of testing eighteen simply supported HSRC deep beams both with and without web openings. The numerical work procedure consisted of testing ten simply supported HSRC deep beams both with web openings. All beams had the same dimensions and flexural reinforcement. They had an overall length of 1400 mm, a width of 150 mm and a height of 400 mm. The investigated test parameters were concrete compressive strength, shape and size of openings, vertical and horizontal reinforcement ratios, shear span to effective depth ratio (a/d ratio) and loading history. The experimental results reveal that the ultimate load capacities for specimens tested under four different repeated loading regimes decrease in the range between 2% and 19% in regards to the control specimens which were tested under monotonic loading regime. The results indicated that the increase in the severity of loading history leads to a decrease in the ultimate shear strength of the deep beams and causes increases in their ductility ratio. The ultimate loads of HSRC deep beams with square web openings size of (50*50mm, 60*60mm and 70*70mm) tested under the repeated loading history (HS-1) which consisting of five phases decreased by (11.4 %, 24.1% and 26.3 %, respectively) compared to that of identical solid deep beam. The ultimate load of HSCR deep beam with circular web openings shape tested under repeated loading history (HS-1) increases by 8.6 % compared to the equivalent square web openings shape. For numerically analyzed beams under repeated loading history (HS-1), the ultimate load increases by 16% when using area of 2500mm2 of circular web openings shape (equal in area to square web opening size 50mm*50mm) and by 13.5% when using rhombus web openings shape of the dimensions 50*50mm in comparison with the case of 60-mm size square web openings.

يھدف ھذا البحث الى التحري التجريبي والتحليلي عن لدراسة سلوك العتبات الخرسانية المسلحة العميقة عالية المقاومة الحاوية على فتحات في وتراتھا المعرضة الى الأحمال التزايدية التكرارية باتجاه واحد. يتألف البرنامج العملي التجريبي من فحص ثمانية عشر من العتبات الحاوية وغيرالحاوية على فتحات في وتراتھا. كما كانت جميع النماذج ذات ابعاد (طول 1400 ملم, سماكة 150 ملم و ارتفاع 400 ملم). فحصت النماذج تحت تأثير ازاحة استاتيكية تزايدية تكرارية باتجاه واحد. اشتملت متغيرات البحث على مقاومة انضغاط الخرسانة و شكل وحجم الفتحات و نسبة حديد التسليح الشاقولي والافقي و نسبة فضاء القص الى الارتفاع الفعال للعتبة وانماط التحميل التكراريةأربعة انماط من التحميل المتكرر سلط على العتبات العميقة مستندة على نتائج فحص النموذج المتحكم. أظھرت النتائج التجريبية انخفاض التحمل الاقصى لھذه العتبات بنسب تتراوح بين 2% و %19 نسبة الى النموذج المفحوص تحت تحميل تزايدي بأتجاه واحد. ھذا يعني ان الزيادة في شدة نمط التحميل المتكرر تؤدي الى تقليل مقاومة القص للعتبات العميقة.


Article
EFFECT OF WEB OPENING'S SHAPE ON THE BEHAVIOR OF HYBRID REINFORCED CONCRETE DEEP BEAMS UNDER REPEATED LOADING

Authors: Sawsan Akram Hassan --- Mohammed Kamil Ali
Journal: Journal of Engineering and Sustainable Development مجلة الهندسة والتنمية المستدامة ISSN: 25200917 Year: 2019 Volume: 23 Issue: 3 Pages: 128-141
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

This research aims to study experimentally behavior of hybrid deep beams with web openings when subjected to two points' monotonic and repeated loading in effect of web openings shape. All tested deep beams have the same flexural (0.0184) and web reinforcement (ρw=0.003) and same dimensions of (1500mm length, 150mm width and 350mm height). In this research, the idea of hybridity was achieved by reinforcing the two shear spans with steel fiber keeping the middle span free from this fiber. The aim was to strengthen shear region against shear failure (diagonal strut failure). To achieve the aim, six deep beams were cast and tested. Three of them were tested under monotonic loading as control beams to the other three beams tested under repeated loading at levels of 55% of the ultimate load of their control beams. The variables studied were: loading type (either monotonic or repeated) and web opening shapes. The results indicated that using different opening shapes (rectangular, circular or square) with an equivalent shape of 1.37% of beam size show that the ultimate load of beams with rectangular opening decreases by 10% as compared with beams with square web openings of the same area. Also, the ultimate load of beams with circular openings increases by 6.8% as compared with beams with square web openings of the same area. Also, it can be concluded that deep beams haves circular openings are increasing in ultimate loads by 17.5% as compared to rectangular web openings shapes with equivalent area.


Article
BEHAVIOR OF HYBRID REINFORCED CONCRETE DEEP BEAMS WITH WEB OPENINGS UNDER REPEATED LOADING

Authors: Sawsan Akram Hassan --- Mohammed Kamil Ali
Journal: Journal of Engineering and Sustainable Development مجلة الهندسة والتنمية المستدامة ISSN: 25200917 Year: 2019 Volume: 23 Issue: 4 Pages: 52-75
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

This research aims to study experimentally behavior of hybrid deep beams when subjected to two point's monotonic and repeated loading in presence or absence of web openings. All tested deep beams have the same reinforcement in flexural (ρ= 0.0184) and web (ρw=0.003) and same dimensions of (1500mm length, 150mm width and 350 mm height). In this research, the idea of hybridity was achieved by reinforcing the two shear spans with steel fiber keeping the middle span free from this fiber. The aim was to strengthen shear wings against shear failure (diagonal strut failure). To achieve the aim, twelve deep beams were cast and tested. Six of them were tested under monotonic loading as control beams to the other six beams tested under repeated loading at levels of 55% of the ultimate load of their control beams. The variables attempts were: loading type (either monotonic or repeated), beam type (either hybrid or non-hybrid), steel fiber (SF) ratio, and finally web opening sizes. The results illustrate that the ultimate load of deep beam with web openings under monotonic loading increases as the SF ratio increases. When SF was added to shear spans with a ratios of 1% and 2% under monotonic loading system, the ultimate load percentages increase are 37.5% and 68.75%, respectively compared with ultimate loads of beams which are without SF. Also, using fiberous concrete in casting the entire length of beams leads to an increase in the ultimate load of 4.55% as compared with deeps beams with the same SF ratio of 1%, and 43.75% as compared with beams cast with conventional concrete. The results using different opening size of square shapes, it was found that the ultimate load decrease as size of web openings increases from 0.61% of beam size to 1.37% of beam size by 10.17% and 25.42%, respectively as compared with hybrid deep beam without openings.


Article
Prediction Of Behaviour Of Reinforced Concrete Deep Beams With Web Openings Using Finite Elements
التنبؤ بسلوك العتبات الخرسانية المسلحة العميقة ذات الفتحات باستخدام العناصر المحددة

Author: Khalaf Ibrahem Mohammad
Journal: AL Rafdain Engineering Journal مجلة هندسة الرافدين ISSN: 18130526 Year: 2007 Volume: 15 Issue: 4 Pages: 1-12
Publisher: Mosul University جامعة الموصل

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Abstract

AbstractThis study presents a nonlinear analysis using the finite element method to predictthe ultimate load and mode of failure for reinforced concrete deep beams with webopenings. Materials nonlinearities due to cracking, plastic flow or crushing ofconcrete and yield conditions of the reinforcing steel are considered. The capabilitiesof the proposed model have been examined and demonstrated by analyzing fivereinforced concrete deep beams with web openings.Keywords: nonlinear, elasto-perfect plastic, finite element, reinforced concrete, deepbeams, web openings

الخلاصةتقدم الدراسة تحليلا غير خطي باستخدام العناصر المحددة للتنبؤ بالحمل الأقصى وشكل الفشل للعتباتالخرسانية المسلحة العميقة ذات الفتحات. تم الأخذ بنظر الاعتبار التصرف غير الخطي للمواد الناتج منتشقق الخرسانة وخضوعها وتهشمها وخضوع حديد التسليح. تم اختبار قابلية النموذج المقترح على خمسعتبات خرسانية مسلحة عميقة ذات فتحات.Received


Article
Experimental Study on Composite Beams with Circular Web Openings

Authors: Waleed Kh. Hadi --- May J. Hamoodi
Journal: University of Thi-Qar Journal for Engineering Sciences مجلة جامعة ذي قار للعلوم الهندسية ISSN: 26645564/26645572 Year: 2014 Volume: 5 Issue: 1 Pages: 43-54
Publisher: Thi-Qar University جامعة ذي قار

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Abstract

The behavior of composite beams with circular web openings is described. Four composite beams comprising one control beam were tested. The perforated beams have six circular openings with various locations. Opening size was fixed (66.7% of the steel section web depth) while number of openings in each composite beam was varied. Deflections at midspan and at openings were observed. Cracking of concrete slab and behavior of each opening were explained in detail. Tests indicated that circular web opening reduced the strength of composite beams. The behavior of composite beams relatively unaffected by the presence of circular web openings up to first yield. Less effect for the inclusion of circular web openings located out of midspan. The concrete slab has limited contribution to the strength of composite beams with circular web openings.


Article
VALIDATION OF FINITE ELEMENT MODELING FOR RECTANGULAR REINFORCED CONCRETE BEAMS WITH WEB OPENINGS

Author: Ahlam Sader Mohammed
Journal: Journal of Engineering and Sustainable Development مجلة الهندسة والتنمية المستدامة ISSN: 25200917 Year: 2019 Volume: 23 Issue: 3 Pages: 89-98
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

The present paper aims to validate ABAQUS finite element model to analysis the rectangular reinforced concrete beams in order to study web opening effect on the shear, and ultimate strength of these beams. The validation has been achieved through comparison of load-- deflection curves obtained from the finite element model with those of experimental works of another researcher. The dimensions and flexural reinforcement of the beams were kept the same. The investigated test parameters were the size and the location of the openings. Comparison between load-deflection curves obtained from finite element model with those of experimental works indicates good agreement such that the proposed model can be adopted in future for further studies.


Article
Nonlinear Finite Element Analysis of Steel Fiber Reinforced Concrete Deep Beams With and Without Opening
التحليلِ اللاخطّي للعتبات الخرسانية المسلحة العميقة والمقواة بألياف حديد الصلب مع و بدون الفتحات باستخدام طريقة العناصرِ المحددِة

Author: Hayder Qais Majeed حيدر قيس مجيد
Journal: Journal of Engineering مجلة الهندسة ISSN: 17264073 25203339 Year: 2012 Volume: 18 Issue: 12 Pages: 1421-1438
Publisher: Baghdad University جامعة بغداد

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Abstract

This paper presents a nonlinear finite element modeling and analysis of steel fiber reinforced concrete (SFRC) deep beams with and without openings in web subjected to two- point loading. In this study, the beams were modeled using ANSYS nonlinear finite element software. The percentage of steel fiber was varied from 0 to 1.0%.The influence of fiber content in the concrete deep beams has been studied by measuring the deflection of the deep beams at mid- span and marking the cracking patterns, compute the failure loads for each deep beam, and also study the shearing and first principal stresses for the deep beams with and without openings and with different steel fiber ratios. The above study indicates that the location of openings and the amount steel fiber are affects to the behavior and strength of deep beams. And also when the results of the experiments taken from the literature were compared with the results obtained from the beam modeled with ANSYS finite element program, it was shown that the results of computer model gave similar results to the experimental behavior.

يقدم هذا البحث نمذجة وتحليل لاخطي للعتبات الخرسانية المسلحة العميقة والمقواة بألياف حديد الصلب مع و بدون الفتحات ((SFRC متعرضة لحمل مركز بنقطتين باستخدام طريقة العناصر المحددِة . حيث تم نمذجة العتبات باستخدام برنامج ANSYS . وقد تباينت نسبة ألياف الصلب من 0 إلى %1.0. حيث يتضمن البحثً دراسة تأثير محتوى ألياف الصلب للعتبات الخرسانية المسلحة العميقة مع و بدون الفتحات من خلال قياس انحراف العتبات في وسط الفضاء و من رصد أنماط التشققات. كذلك تم حساب أحمال الفشل لجميع النماذج. أضافة الى ذلك فقد تم دراسة أجهادات القص والاجهادات الرئيسية ومن الدراسة المشار إليها أعلاه وجد أن موقع الفتحات وكمية ألياف الصلب ممكن ان تؤثر على سلوك وقوة العتبات العميقة. و أيضا وجد إن نتائج التجارب العملية التي أجريت سابقاً عند مقارنتها مع النتائج من برنامج ANSYS للعناصر المحددة، تبين أن نتائج الكمبيوتر لتمثيل النموذج تعطي سلوك مماثل للسلوك المختبري.


Article
Finite Element Investigation on Shear Lag in Composite Concrete-Steel Beams with Web Openings
التحري بطريقة العناصر المحددة لتخلف القص في العتبات المركبة من الفولاذ والخرسانة بوجود فتحات في وترة الروافد الفولاذية

Authors: Rafa'a Mahmood Abbas رافع محمود عباس --- Hayder Jaber Shakir حيدر جابر شاكر
Journal: Journal of Engineering مجلة الهندسة ISSN: 17264073 25203339 Year: 2015 Volume: 21 Issue: 3 Pages: 11-33
Publisher: Baghdad University جامعة بغداد

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Abstract

In this paper, effective slab width for the composite beams is investigated with special emphasis on the effect of web openings. A three dimensional finite element analysis, by using finite element code ANSYS, is employed to investigate shear lag phenomenon and the resulting effective slab width adopted in the classical T-beam approach. According to case studies and comparison with limitations and rules stipulated by different standards and codes of practice it is found that web openings presence and panel proportion are the most critical factors affecting effective slab width, whereas concrete slab thickness and steel beam depth are less significant. The presence of web opening reduces effective slab width by about 21%. Concentrated load produces smaller effective slab width when compared with uniformly distributed and line loads. Generally, standard codes of practice overestimate effective slab width for concentrated load effect, while underestimate effective slab width for uniformly distributed and line load effect. Based on the data available, sets of empirical equations are developed to estimate the effective slab width in the composite beams with web openings to be used in the classical T-beam approach taking into account the key parameters investigated.

تم في هذا البحث اجراء دراسة تاثير وجود الفتحات في وترة الروافد المركبة من الفولاذ والخرسانة على العرض الفعال للشفة الخرسانية. تم عمل نماذج ثلاثية الابعاد بطريقة العناصر المحددة, باستعمال برنامج التحليل الجاهز ANSYS, للتحقق من ظاهرة تخلف القص والعرض الفعال للشفة الخرسانية الناتج عنها. بينت نتائج هذه الدراسة والمقارنة مع متطلبات ومحددات المراجع والمدونات القياسية ان تاثير وجود فتحات في وترة الروافد الفولاذية ونسبة ابعاد البلاطة الخرسانية هي اهم العوامل المؤثرة على العرض الفعال للشفة الخرسانية وبدرجة اقل يؤثر سمك البلاطة الخرسانية وعمق الرافدة الفولاذية. ان وجود فتحات في وترة الروافد الفولاذية يقلل العرض الفعال بمقدار 21% وان العرض الفعال للشفة الخرسانية بسبب الاحمال المركزة هو اقل مما في حالة الاحمال المنتظمة او الاحمال الخطية. وبشكل عام, فان المدونات القياسية تبالغ في تقدير العرض الفعال الناتج عن الاحمال المركزة وتقلل من تقديره في حالة الاحمال المنتظمة او الاحمال الخطية. واستنادا الى البيانات المتوفرة تم اقتراح علاقات رياضية مبسطة تساعد المصمم على احتساب العرض الفعال للبلاطة في العتبات المركبة ذات الفتحات بصورة مباشرة من خلال بعض المتغيرات التي تمت دراستها.

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