大体积混凝土温度有限元分析及温度梯度限值研究

Study on Temperature Finite Element Analysis and Temperature Gradient Limit of Mass Concrete

应用ANSYS有限元分析软件,对佛山某建筑广场工程中1.3m厚及3.8m厚的大体积混凝土承台温度场进行分析。结合大体积混凝土温度监测结果,揭示出大体积混凝土温度分布规律。研究大体积混凝土中心、边缘部分中300,500mm深度点与表面的温差、温度梯度,探讨其变化对混凝土表面裂缝的影响。依据对大体积混凝土承台水泥水化温度的ANSYS模拟与实测结果的校验,归纳出深度为300,500mm内的混凝土在不同龄期的温度梯度限值,该温度梯度限值可作为大体积混凝土温度裂缝监测的预警值。

The finite element analysis software ANSYS is used to analyze the temperature field of the mass concrete cap of 1. 3 m thick and 3. 8 m thick in a building square project in Foshan. Combined with the temperature monitoring results of mass concrete,the temperature distribution law of mass concrete is revealed. The temperature difference and temperature gradient of the 300,500 mm depth point and the surface in the center and edge of the mass concrete are studied,and the influence of the change on the cracks of the concrete surface is discussed. According to the verification of the ANSYS simulation and the measured results of the hydration temperature of the mass concrete bearing platform cement, the temperature gradient limit of the concrete in different ages is summed up in the depth of 300,500 mm,and the temperature gradient limit can be used as the early warning value for the monitoring of the temperature crack in the mass concrete.