整环盾构隧道管片原型加载系统的研究综述

RESEARCH ON PROTOTYPE LOADING SYSTEM FOR SEGMENT OF INTEGRAL RING SHIELD TUNNEL:A REVIEW

地铁运营时因受基坑开挖、周边卸载和地面堆载等因素影响,盾构隧道管片经常出现横向变形较大和管片开裂等问题,造成经济损失的同时还带来很大的安全隐患。为优化管片配筋,常采用整环盾构管片原型加载系统对管片进行加载试验,来研究其结构服役性能。文中对国内外整环盾构管片原型加载系统的研究现状进行阐述,根据管片放置方式,将其分为平躺式和站立式。分析以上系统的加载机理和优缺点,将站立式与平躺式加载系统进行对比,平躺式主要适合深埋且自重效应小的单环或多环管片,站立式主要适合浅埋且自重效应大的单环或多环管片。鉴于这两类加载系统仍存在一定缺陷,因此对此类系统的进一步改善提出了相应建议。

Due to the influence of foundation pit excavation,surrounding unloading and ground loading,shield tunnel segments subjected to large lateral deformation and cracking,which cause economic losses and great potential safety hazards.In order to optimize the segment structure,the prototype loading system of the shield segment is used to carry out the loading test of the shield segment to study its structural service performance.The research status of the prototype loading system of shield segment at home and abroad is introduced.According to the shield segment placement mode,it is divided into lying type and standing type.This paper analyzes the advantages and disadvantages of loading mechanism of the above system,comparing the standing and lying type loading system.The results show that the standing loading system is suitable for single ring or multi-ring segments with shallow buried and low self-weight effects,whereas,the lying type loading system is suitable for single ring or multi-ring segments with deep buried and large self-weight effects.Considering the two loading systems still have certain defects,it puts forward corresponding suggestions for further improvement of such system in the future.