Measurement and Evaluation of the Thermal Expansion Coefficient of Rock-Filled Concrete

Rock-filled concrete (RFC), formed by pouring self-compacting concrete (SCC) into rock blocks, is a newly developed type of mass concrete. It is important to determine its coefficient of thermal expansion (CTE) in engineering applications. In this study the CTE of RFC was determined for the first time using thermal expansion tests. RFC with three rock rates was measured at different ages. Meanwhile, the CTEs of SCC and rock blocks were experimentally tested for subsequent numerical simulation and theoretical analysis. The CTE of RFC was then evaluated numerically and theoretically based on the constituent materials. A three-dimensional finite element model was built for the numerical simulation of the thermal expansion tests of RFC. In addition, two composite models were used for the theoretical evaluation of the CTE of RFC based on the material parameters of SCC and rock blocks. The obtained numerical and theoretical CTE values agree well with the experimental CTE value. The numerical simulation and theoretical formulas can be used to estimate the CTE of RFC, thereby overcoming the high cost of complex experimental measurements.