Measurement and analysis of thermal expansion coefficients of mortar and limestone cooled to cryogenic temperatures

Abstract

The force caused by the difference of thermal expansion coefficient between concrete aggregates at ultra-low temperature will inevitably affect the structure and should be considered in the structural design. The coefficient of thermal expansion of cement mortar and stone was measured by resistance strain gage test technology in ultra-low temperature environment, and the variation law of average linear expansion coefficient with temperature was obtained. The results show that the thermal expansion coefficients of cement mortar and stone have similar variation rules with the change of temperature. The stress state of cement mortar and stone under ultra-low temperature does not affect their thermal expansion coefficient. Thermal expansion coefficient of cement mortar under ultra-low temperature is affected by size effect.