Coupled effects of stress and temperature change on concrete structures

Confirmation seminar presented by Mathusan Mahenthiran

Concrete is the industry preferred construction material due to its many beneficial characteristics. However, certain behaviours of concrete require further clarifications, notably cracking due to restrained volume changes. The challenge in accurately estimating the actual magnitude of the tensile stresses in the concrete due to restrained deformations has hindered the development of robust models for cracking assessment. The challenge is further exacerbated by the unreliable predictions of the contributing factors such as autogenous shrinkage and tensile creep by the current standards. Another critical gap is the stresses due to restrained thermal deformation, which will be shown to be revised to properly account for the effect of the zero-stress temperature.

Using a combined experimental and analytical approach, this study aims to first generate a comprehensive set of reliable data on the key factors related to cracking in concrete due to restrained deformation, and on that basis, propose revised models for their prediction. Another important aim of this research is to modify the current cracking analysis to rationally account for the zero-stress temperature and different types of deformation from early ages