EHAVIOR OF HIGH STRENGTH R.C ONE WAY SLABS UNDER THE EFFECT OF CONCENTRATED AND LINE LOADS.

Document Type : Original Article

Authors

1 Colonel. Doctor Engineer (Armed Forces - Administration of Military Works).

2 Assistance Prof. Structural Engineering Department, Cairo University.

3 Prof. of concrete Structural, Structural Engineering Department, Cairo University.

4 Head of Structural Engineering Department, Cairo University.

Abstract

Abstract The use of high strength concrete with a compressive strength greater than 42 KN/mm² is recently increased and accepted by either the designers or the contractors. Most of the current designs building codes are based on the experimental works for normal concrete with a compressive concrete strength less than 40 KN/mm². Developing a satisfactory procedure for the design of structures using high strength concrete needs an additional consideration, validation or modification of the existing design building codes. This research deals with studying the behavior of high strength reinforced concrete slabs under the effect of either concentrated or line loads. Seven simply supported one way slabs were cast and tested as a part of compressive experimental program[1] The slabs had variable rectangularity ratio, slab thickness, load eccentricity, percentage of steel reinforcement, and with different arrangement of main reinforcement. The slabs crack pattern and crack propagation, slab deflections, and both the strains on either concrete extreme fiber and steel strains were also measured and discussed. Analytical study for the slabs was conducted using a nonlinear finite element computer program (Assembly) to numerically prediction the nominal strength of such slabs under the effect of different situations of concentrated loads. In addition, a comparison between results from some available design building codes with the experimental results was done.