Investigation of thermal stress distribution in fiber-reinforced roller compacted concrete pavements

Roller compacted concrete (RCC) is a kind of concrete that is used in pavement construction. RCC has the strength and performance of conventional concrete with the economy and simplicity of asphalt. Unfortunately, this type of concrete is less sensitive to cracking in relation with drying shrinkage and thermal stresses. In this way, reinforcement of RCC with fibers would be a useful solution. The main aim of this study was therefore investigating into thermal stress distribution in fiber-reinforced RCC (FRRCC) pavements. Firstly, the thermal stress induced in fiber-reinforced rigid pavements was modeled by using “thermal expansion law” in short fiber composite materials and “Eshelby’s model” extended from the “theory of elasticity”. Consequently, an instrument was developed to measure the heat gradient in FRRCC samples at different origin temperatures of 40℃, 60℃, and 80℃. Steel and polypropylene fibers were used to prepare FRRCC specimens. The analytical results showed that fiber modulus, fiber volume fraction, fiber Poisson’s ratio, and fiber coefficient of thermal expansion determine the induced thermal stress in FRRCC pavements. The analytical outcomes were straightly correlated with the experimental results.