NEHRP Clearinghouse

Title
Effect of Slabs on the Flexural Behavior of Beams.
File
PB90262700.pdf
Author(s)
Pantazopoulou, S. J.; Moehle, J. P.
Source
National Science Foundation, Washington, DC., October 1987, 131 p.
Identifying Number(s)
UCB/EERC-87/17
Abstract
It has been observed in experimental studies that floor slabs strengthen and stiffen beams, especially when slabs undergo tension. This fact is ignored in current design and analysis practices, thus resulting in significant beam overstrength. In this regard, assessment of the contribution of floor slabs to the stiffness and strength of the supporting beams is crucial in achieving the desired hierarchy of strength within the structure. Several analytical models that aim to quantify this effect are developed in the report. Simple methods of practical interest are also presented. The fundamental concept underlying all the analytical models is that the action of floor slabs is of membrane nature, primarily controlled by the amount and the mechanical properties of the slab reinforcement. Further, the classical assumption of plane sections, used to analyze flexural behavior of beams, is relaxed. Effects of flexible transverse beams on the overstrength provided by the slab are also included in the study. The analytical models for the effect of floor slabs on the behavior of beams are verified by correlation with measured response of several interior and exterior slab-beam-column connections.
Keywords
; Floors; Tension; Earthquake resistant structures; Beams (Supports); Loads (Forces); Slabs; Stress analysis; Earthquakes; Experimental data; Stiffness; Structural members; Mathematical models; Structural analysis; Seismic waves