A Study on Coefficient of Thermal Expansion and Elastic Modulus used for Thermal Stress Analysis by 3-D Finite Element Method at the upper Slab of a RC Box Culvert

Abstract

The results of thermal stress analysis in concrete structure are influenced by coefficient of thermal expansion and elastic modulus which are used as parameters.
In this paper the coefficient of thermal expansion and elastic modulus to need for exact thermal stress analysis of internal restraining thermal stress were considered by using measured temperature, strain and thermal stress of concrete at the upper slab of a real RC box culvert.
First, coefficient of thermal expansion was considered by dividing into two section that rising and falling section of inner temperature of concrete. According to the results, coefficient of thermal expansion on rising section was larger than that on falling section.
Then, elastic modulus was considered by four methods. And, thermal stress were calculated by three-dimensional finite element method using four methods of elastic modulus were comparing with the measured thermal stress. According to the results, we could consider the more effective method for selecting elastic modulus to analyze internal restraining thermal stress using threedimensional finite element method.