Compressive Membrane Capacity Estimates in Laterally Edge Restrained Reinforced Concrete One-Way Slabs

Welch, R.W.; Hall, W.J.; Gamble, W.L.

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https://hdl.handle.net/2142/14243 Copy

Description

Title

Compressive Membrane Capacity Estimates in Laterally Edge Restrained Reinforced Concrete One-Way Slabs

Author(s)

• Welch, R.W.
• Hall, W.J.
• Gamble, W.L.

Issue Date

1999-05

Keyword(s)

• Reinforced concrete
• Lateral restraint
• One-way slabs

Abstract

The load capacity of laterally restrained reinforced concrete one-way slabs is estimated in compressive membrane theory with use of a midspan deflection. However, the midspan deflection estimates exhibit large variability. The point of peak thrust leads to a more accurate index of the peak load capacity than midspan deflection. The calculation of the thrust within the compressive membrane theory is a maximum when the slab's axial shortening and the outward support movement are a maximum. The use of the peak thrust to select the peak capacity, when combined with a modification to Park and Gamble's (1980) compressive membrane theory, provides an improved overall correlation to the experimental data for a large range of span-to-thickness ratios (2.7 < Lih <28.3). In this study, peak midspan deflection estimates were developed to define the peak point of the load-deflection curve. The slab's axial concrete compressive strength and the peak concrete compressive strain are used within a curvature and geometrically based deflection equation, to predict the midspan deflection. The post-peak trough and ultimate points are related empirically to the tensile membrane curve, and the generated load-deflection curve compares well with the experimental data. A simple compressive membrane load capacity estimate for laterally restrained reinforced concrete one-way slabs is developed for field use. The estimate uses the axial force-moment interaction equations and a ratio for the peak thrust to the slab's axial capacity, and results in an accurate estimate of the peak compressive membrane capacity using yield line theory.

Publisher

University of Illinois Engineering Experiment Station. College of Engineering. University of Illinois at Urbana-Champaign.

Series/Report Name or Number

Civil Engineering Studies SRS-627

Type of Resource

text

Language

en

Permalink

http://hdl.handle.net/2142/14243

Sponsor(s)/Grant Number(s)

• U.S. Army.
• Department of Civil and Mechanical Engineering; U.S. Military Academy.

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