北京地铁联络通道三维冻结温度场数值模拟

Numerical Simulation of Three-Dimensional Freezing Temperature Field in Beijing Metro Cross Passage

以北京地铁7号线一区间联络通道兼泵房冻结法施工为背景,分析联络通道冻结温度场。根据倾斜放射状布置的冻结管群建立三维计算模型,利用有限差分软件FLAC 3D对冻结温度场进行数值模拟,并与现场实测温度作对比。结果表明:冻结管放射状布置时,沿联络通道不同横截面温度场分布不尽相同,冻结管越密集,温度场发展得越快,所形成的冻结壁越厚;冻结壁内部温度场发展速度大于外部,且内部温度场发展更为均匀;同一测温点数值模拟温度曲线与实测温度曲线基本一致,验证了数值计算的可靠性。

Based on the freezing construction method of cross passage and pump house in a section of Beijing Metro Line 7,the freezing temperature field of cross passage was analyzed.According to the three-dimensional calculation model of the inclined radial arrangement of frozen pipe group,the finite difference software FLAC 3D was used to simulate the freezing temperature field,and compared with the field measured temperature.The results show that when the frozen pipes are arranged radially,the distribution of temperature field along different cross sections of the cross passage is not the same.The denser the frozen pipes are,the faster the temperature field develops,and the thicker the frozen wall is.The development speed of the internal temperature field of the frozen wall is faster than that of the external,and the development of the internal temperature field is more uniform.At the same temperature measuring point,the simulated temperature curve is basically consistent with the measured temperature curve,which verifies the reliability of the numerical calculation.