Nonlinear Finite Element Analysis of Ferro-cement Slabs and Shell Roofs

Abstract

The present work involves developing an analytical model to study the behavior of ferro-cement slabs and shell roofs, and to adopt the most realable constitutive relationships for the mortar material to predict the nonlinear response of ferro-cement roofs by using the finite element method. To represent the mortar and wire mesh, a layered approach is used. Mortar is considered as a strain-hardening material and exhibiting strain-hardening behavior till it reaches the peak stress, beyond which, mortar enters the descending portion (strain softening) until it reaches the crushing strain. Tension stiffening is used to model the post- cracking tensile strength of the mortar. Under further loading in post-cracking stage shear retention is used to model the shear transfer throughout the cracks. The behavior of steel reinforcement and wire mesh is considered as elastic perfectly plastic with linear strain hardening. The predicted results of ferro-cement slab and cylindrical shell roofs had shown a good agreement with the published experimental results.