Strength deterioration of nonprismatic reinforced concrete beams

Abstract

Cracking of reinforced concrete structures reduces stiffness and a subsequent deterioration in the capacity of structural elements. This study has investigated the use of a central difference approximation to obtain curvature mode shapes for structural elements based on the measured natural frequency and modal displacements for each load step. The findings of numerical analysis, conducted using finite element software, has been compared with experimental results. This paper also presents a proposed method of damage detection for structural elements based on an estimate of stiffness degradation using nonprismatic beam element called the Modified Flexure Damage Index (MFDI). This approach esti..