BEHAVIOR OF FLANGED LIGHTWEIGHT CONCRETE BEAMS UNDER COMBINED STRESSES

Abstract

This research was commenced with the impartial of investigating lightweight concrete “LWC” beams behavior, experimentally and numerically. Literature review was carried out in the field of LWC in order to determine the research gaps or weak points to commence this research.

Experimental work was carried out. The experimental work was divided into two main phases. The first phase included the identification of some of the mechanical properties of the LWC namely the compressive and tensile strengths and its tension stiffening capability. The second phase included testing specimens of LWC beams (L and T-shaped) under combined stresses for determination of the ultimate resistance, mode of failure, ultimate angle of twist, and load-deflection curve for all tested beams.

A numerical modeling procedure was achieved, where nonlinear finite-element model (i.e. software package “ANSYS15”) was tooled, to verify the experimental results. 34 LWC beams (L and T-shaped) were investigated, under combined stresses, in order to determine the impact of flange width, span to depth, load eccentricity, and transverse reinforcement ratios on LWC. An Analytical procedure was developed to predict the loading capacity of LWC beams subjected to combined stresses. The reliability of the predicted equation was verified by comparing the results with experimental and finite element models. Finally, conclusions were deduced and recommendations for future research were suggested