Experimental and finite element investigations on the temperature field of a massive bridge pier caused by the hydration heat of concrete

摘要

Thermal cracks are the main concerns when temperatures increase in mass concrete structures. It is important to explore the temperature rise rules and to find effective methods to control the hydration heat of mass concrete structures. In this study, based on a 1:5 scaled segmental model test of an arch bridge, the temperature field and temperature time histories for the core concrete of the massive pier caused by the hydration heat were measured. The finite element method (FEM) was also used to simulate the hydration temperature field through commercial FEM software. The tested temperature time history curves showed that the temperature of the concrete increases rapidly but decreases slowly. The maximum temperature at the center of the concrete reached 86.6 degrees C, and the maximum temperature difference from the center to the surface reached 30.6 degrees C, which may lead to concrete cracks, It was also found that the calculated temperature contours and temperature time history curves agreed well with the tested ones, which verified the accuracy of the FE model. Finally, the verified FE model was used to perform parametric analysis to explore the effects of thermal parameters on thermal behaviors, and an effective heat control method, i.e., the pipe cooling method with cold water, was proposed. Thermal stress analysis was also conducted and results showed that the pipe cooling method is an effective way to reduce both the hydration temperature and thermal stress. (C) 2018 Elsevier Ltd. All rights reserved.