FACTORS AFFECTING THE UNSYMMETRICAL PUNCHING SHEAR RESISTANCE OF HIGH- STRENGTH CONCRETE SLABS

Document Type : Original Article

Authors

1 Prof. of RC Structures.

2 Assist. Prof .of Structural Eng.,

3 PhD student.

Abstract

ثحبلا صلخلم
تعتبر البلاطات اللاکمرية من اکثر النظم الانشائية استخداما فى مجال صناعة الانشاءات لما تمتاز بة من مرونة فى استخدامات المنشا
( وزيادة حجم الفراغات المتاحة وقلة ارتفاع المبنى النسبى بالاضافة الى سهولة التنفيذ والوفر فى زمن التنفيذ. وفى هذا الصدد تم صب ( 5
150 ) مم بها عمود خرسانى عند حافة البلاطة وتم تسليح جميع البلاطات بحديد قطر 18 مم فى جانب *1450* بلاطات بابعاد ( 1450
الشد وحديد قطر 10 مم فى جانب الضغط .
وقد تم استخدام برنامج للحاسب الآلى يتبع طريقة العناصر المحددة فى تمثيل جميع العينات للتنبؤ بسلوکها. کما تم عمل مقارنة بين النتائج
العملية والنظرية لاظهار الاختلاف فى السلوک وتشمل هذه المقارنة احمال الانهيار وکذلک التشکلات والانفعالات.
ABSTRACT
One of the most common floor systems is the flat slabs. It provides architectural flexibilities, more clear space, less building height, easier form work and consequently shorter construction time. A serious problem that can arise in flat slab is the brittle punching shear failure due to shear and moment transfer from slabs to columns. As a result of the combined effect of the moment and the shear, stress is no longer uniformly distributed in the vicinity of the column. High- strength concrete is a new type of concrete that having mechanical properties that are far superior to those of conventional concrete. The main characteristics of HSC are then improved. This thesis discusses the behavior of punching shear strength of flat slabs subjected to centric and eccentric loading, with and without shear reinforcement. In this way, 5 concrete slabs (1450 ×1450×150) with edge column were casted to examine different parameters such as concrete strengths and effect of shear reinforcements (central mesh and shear studs). A finite element program (ANSYS® Release 14) was applied to model the tested specimens to predict the behavior and compatibility between experimental and theoretical investigations to display the difference in behavior considering cracking and failure loads as well as deformations and strains.

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