Membarane action in orthotropically reinforced concrete rectangular slabs restrained two adjacent

Dissertant

Yasin, Hammam Khalil

University

University of Technology

Faculty

-

Department

Department of Production Engineering and Metallurgy

University Country

Iraq

Degree

Master

Degree Date

2006

English Abstract

The majority of the previous works on the subject of membrane action in R.C.

rectangular slabs have considered the slab to be isotropic ally reinforced in the two orthogonal directions and equal amounts of reinforcement have been assumed to exist at negative and positive bending moment regions.

The main reason for such consideration was to simplify the method of membrane analysis and to reduce the number of the involved parameters.

However, in order to evaluate the actual effect of membrane action in R.C.

two-way rectangular stabs, the practical case of orthotropic reinforcement is essentially required to be taken into account.

The present research includes this important parameter and therefore it is aimed from the present work to furnish a rigorous rigid-plastic analysis of membrane action in orthotropic ally reinforced concrete rectangular slabs having two edges clamped against rotation and horizontal translation while the other two are simply supported and the slab being subjected to uniformly distributed load.

Based on the simple yield line theory, the correct mode of failure and the associated collapse uniform load are first determined for this slab case.

Then by adopting the pattern of failure predicted by the yield line theory, an upper bound rigid-plastic solution is presented that takes into account the significant effects of membrane forces induced in the plane of the slab with continuing deflection.

Therefore this solution describes the load-deflection behavior of such slabs under the combined effect of bending and membrane action.

The load-deflection behavior of a specified reinforced concrete slab has been found to be largely affected by many parameters including the slab aspect ratio (m), steel ratio (p), concrete strength (fe'), yield stress of steel (fy) and coefficient of orthotropic (y).

The slab is found to carry loads far beyond those predicted by Johansen's simple yield line theory and this enhancement in toad is aerator for slab with lower values of(m), (p) and (fy) and higher values of (O) and (y).

A theoretical studies of maximum yield load reveals a promising saving in reinforcement by using stronger concrete.

For slabs axially restrained on two adjacent edges and the other two edges simply supported, such saving in reinforcement could be as high as (55 %) if the slab is lightly loaded, and (34 %) for a slab under moderate load.

Main Subjects

Civil Engineering

Topics

• Reinforced concrete

• APA
• MLA
• AMA

Language

English

Data Type

Arab Theses

Record ID

BIM-305582