地铁施工中地下管线不同因素对其安全性影响

Influence factors of the different effect on the pipeline safety in the subway construction

针对城市地铁施工中既有输水管线多次发生的破坏问题,采用数值计算方法,深入分析和研究了管线埋深、管径、以及弹性模量等不同因素对其安全性的影响.研究结果表明:管线弹模对管线的安全性的影响较弱;对管线安全性影响较大的因素则为管线的埋深和管径的变化.管径的变化对管线的位移变化影响较小,对管线的受力情况影响较大;管线埋深的改变则对管线的位移、受力等均有较大的影响.因此,就提高管线的安全性而言,可以从改变管线的埋深和管径的大小等角度出发,提出有效的措施,以此改善和提高管线运营的安全性.

This paper established a numerical model for subway tunnel and pipeline interaction, and analyzed the different factors including the change of the pipeline＇s diameter, the change of the pipeline＇s elastic modulus, and the change of the pipeline＇s buried depth which affect the pipeline security. The numerical conclusions show that on the condition of the pipeline＇s different buried depth, it may be changed which the pipeline＇s displacement change law, the pipeline＇s stress condition, and pipeline＇s bending and torque moment. With the increase of depth, the pipeline displacement decreasing, and the pipeline＇s different direction stress increasing, and the pipeline＇s bending and torque moment extreme value in different calculation section increasing. On the condition of the pipeline＇s different elastic modulus, the change of the pipeline＇s elastic modulus did not effectively change the pipeline＇s displacement and its stress condition in the stratum, it was only moderate change which the pipeline bending and torque moment. From the calculation results, it is revealed that the change of the pipeline＇s elastic modulus has little effect on the pipeline＇s displacement and stress condition. And it has little effect on the pipeline＇s bending and torque moment. Therefore, it doesn＇t improve its safety effectively only by raising the pipeline＇s elastic modulus. On the condition of the pipeline＇s different diameter, it is concluded from the numerical results that the change of the pipeline＇s diameter may change the pipeline＇s displacement, stress and its bending and torque moment. In contrast, the change of the pipeline＇s diameter has little effect on its displacement in the stratum. But it has great effect on its bending and torque moment. Therefore, it is clearly concluded that the pipeline＇s elastic modulus has little effect on its safety from the above-mentioned affect factors analyzed. And the factors which the pipeline＇s buried depth and its diameter have been great influence. The change of the pipeline＇s diameter has great influence on its displacement and stress condition in the stratum. So that, to improve the safety of the pipeline maybe change the pipeline＇s buried depth and its diameter, and put forward some effective measures to improve and raise the pipeline safe operation.