盾构隧道管片橡胶密封垫的优化设计方法

An Optimal Design Approach for the Rubber Sealing Gasket in Shield Tunneling

地下工程,结构防水是关键。针对目前盾构隧道管片接缝弹性密封垫以经验为主的设计思路,提出利用数值模拟手段,通过对压缩变形情况下弹性密封垫的孔洞合理变形、薄弱处应力集中、完全压缩到沟槽时压力大小、最大张开量下接触应力的大小及其分布等多因素的综合分析,提出以橡胶密封垫表面接触应力和完全压缩到沟槽内的闭合压力作为盾构隧道管片接头弹性密封垫断面设计的双控指标,该设计理念已应用于国内某大型隧道的建设当中,防水效果理想。

The waterproof is a key point to the underground structures.At present,the design of elastic rubber gasket in shield tunnel lining joint almost depends only on experience.In order to improve the way of design,a numerical simulation method is put forward.A synthetical analysis of the holes in gasket section is done about the reasonable deformation under compression,stress concentration in weak position,the value of pressure when gasket is compressed in groove completely,and the value and distribution of contact stress with maximal allowable expansion of the lining joints.Then the rubber gasket surface contact stress and the closure pressure of the gasket compressed completely down to the groove are chosen as a dual-control index for section design of elastic rubber gasket of shield tunnel on segment joint.This new way was applied in gasket section design in a domestic large diameter shield tunnel and the rusult shows that the waterproofing is perfect.