Research on the influence of different water-passing time on the cooling of mass concrete in the case of pipe cooling

In combination with the construction of a large-volume concrete of a 630m^3 pile cap of a bridge, according to the heat transfer equation of the concrete hydration heat process, the finite element analysis software Midas/FEA is used to establish a three-dimensional solid finite element model of the 1/4 cap. The temperature field and stress field are simulated, and the results are in good agreement with the on-site temperature monitoring results. The effect of different lengths of water flow on the hydration heat process of large-volume concrete pile caps under the condition of pipe cooling is studied. The results show that the time to reach the peak temperature of the concrete inside it is greatly shortened when the pipe cooling is taken into account. When the water flow time is 5 days, the maximum temperature difference between the surface and the inside is 22.76°C. After 360h, the internal center point temperature of the cap is 34.56°C, which meets the requirements of the specification. Analyzing the reasons for the deviation between the actual measured temperature and the theoretical temperature inside the concrete has certain reference significance for the construction of mass concrete in the future.