| The paper takes freezing-sealing pipe roof of the Gongbei Tunnel as the research background.The development and change law of freezing temperature field in active freezing period of tunnel is studied by field measurement and numerical simulation.(1)The temperature change of the freezing pipe in the Gongbei Tunnel,the temperature change in the top pipe and the soil temperature change were monitored.Through the monitoring results,the change of freezing temperature field in the tunnel during the active freezing period is analyzed,and the development and change law of temperature in pipe and soil mass are summarized(2)On the basis of considering the latent heat of soil,the 2-d plane model of the tunnel was built with the finite element software ABAQUS,and the change process of freezing temperature field under typical parameters of the Gongbei Tunnel was calculated.According to the calculation results,the variation law of freezing temperature field in and around the pipe jacking in different soil layers is analyzed,and the change rule of frozen soil curtain and frozen soil temperature on both sides of pipe jacking in the same soil layer.After that,the finite element calculation results are compared with the field monitoring data to verify the reliability of the finite element calculation.(3)Since the freezing temperature field is easily disturbed by external factors during the freezing process of the tunnel.Therefore,the influences of the initial ground temperature,the brine temperature of the round freezing tube,the brine temperature of the shaped freezing tube,and the spacing of the round freezing tube on the freezing temperature field of the tunnel were studied.Through finite element software,the development and change rules of freezing temperature field under single factor change and multi-factor orthogonal change are calculated and analyzed,and the influence of various factors on freezing temperature field is summarized.Figure[41]table[30]reference[49]... |
PDF Full Text Request