Abstract:
Temperature effect analysis of concrete frame structures is the basis of crack control. The simulation and monitoring of the temperature field in the construction stage can guide the early temperature control of concrete, and further calculation of temperature stress in construction stage combined with structural analysis can provide reference for cracking prevention. Based on the comprehensive transportation hub project of Beijing City Sub-central Station, this paper conducts thermal test of concrete materials to calibrate thermal parameters, proposes a refined numerical simulation method of temperature field in the construction stage of the structure, establishes a monitoring system to monitor the temperature field in the construction stage in real time, and verifies the temperature field simulation method through a comparison with the measured data. The research shows that the concrete pouring process is affected by multiple factors such as heat release by hydration, solar radiation and convective heat transfer, and the temperature change of concrete is complicated. The maximum temperature rise in winter can reach 28 ℃. Numerical simulation and structural monitoring in the construction stage can provide support for understanding the early temperature cracks of concrete. The thermal parameters of concrete should be calibrated for temperature field simulation during construction, and the influence of solar radiation should not be ignored. Early temperature cracks of concrete can be controlled by controlling heat generation from internal and external heat sources.