Contribution to the study of damage and progressive failure on composite structures

Author(s)

Volnei Tita

• Document type: Doctoral Thesis
• Press: São Carlos.
• Institution: Universidade de São Paulo (USP). Escola de Engenharia de São Carlos (EESC/SBD)
• Defense date: 2003-08-13

Examining board members

Jonas de Carvalho; Hazim Ali Al Qureshi; Marcilio Alves; Carlos Henrique Daros; Sergio Persival Baroncini Proença

• Advisor: Jonas de Carvalho

Abstract

In this work, material models were proposed to predict the mechanical behavior of composite structures. First of all, it was done a study about damage intra-ply and inter-ply (delamination) on composite materials and about analytical and numerical approaches to solve problems of progressive damage on composite structures was performed. After, many specimens were manufactured and experimental tests (tensile, compression, shear and flexural tests) were carried out. Experimental results and information from literature were used to develop some material models, which were implemented using FORTRAN compiler. These material models were compiled with a commercial finite element program (ABAQUS®) in order to evaluate and calibrate parameters of the models. In the first step, computational simulations of tensile and compression test were carried out to evaluate material models implemented. In the second step, the parameters of the material models were calibrated using three case studies (flexural, indentation and impact test) with some staking sequences. After that, a methodology was proposed to evaluate impact problems on composite structures under low velocity. Therefore, this research project not only shows new contributions but also suggests many future investigations. (AU)