考虑气囊效应的盾构隧道密封垫压缩性能分析

Analysis of the Performance of the Shield Tunnel GasketCompression Considering the Balloon Effect

摘要:

盾构隧道密封垫的压缩性能直接关系到其防水性能以及管片是否可以顺利拼装，在以往有关盾构密封垫的相关数值分析中均无法模拟封闭在密闭孔洞中的空气所引发的“气囊效应”.为此专门编制了计算程序，采用有限元方法模拟了密封垫在压缩过程中孔洞的压力变化，并分析了其对于密封垫压缩过程的影响.研究表明：由于孔洞内气体压力的存在，密封垫的孔壁失稳过程明显滞后，闭合压缩力指标提高了10%以上，气囊效应不容忽视.

Abstract:

The shield tunnel gasket compression performance directly related to its waterproof performance and segments assembly. It was impossible to simulate the “balloon effect” caused by the air in the closed holes. So the special programs were made to employ the FEM method to simulate the gasket compression. The research shows that due to the existence of gas pressure in the holes, the process of hole wall instability is significantly delayed, and the closed compression force increases by ten percent, so the “balloon effect” should not be neglected.