管片衬砌配合陶粒可压缩层支护结构型式的模型试验研究  

Model test of new-type support structure for segment lining combined with compressible ceramic

作　　者：胡雄玉[1,2] 何川[1,2] 杨清浩 曹凇宇 

机构地区：[1]西南交通大学交通隧道工程教育部重点实验室,四川成都610031 [2]西南交通大学土木工程学院,四川成都610031

出　　处：《土木工程学报》2017年第12期111-121,共11页China Civil Engineering Journal

基　　金：国家科技支撑计划(2013BAB10B04);国家自然科学基金(U1361210);2016年度西南交通大学博士研究生创新基金

摘　　要：提出一种适用于深部地层TBM工法隧道的管片衬砌配合陶粒可压缩层的让压支护技术,结合台格庙矿区TBM施工的长距离斜井工程,采用模型试验方法,从管片衬砌弯矩、轴力、变形、破坏特征对比分析陶粒和碎石可压缩层的让压效果,从可压缩层的压缩变形路径和颗粒移动特征角度揭示各自的让压机制。研究结果表明:陶粒内部蜂窝状构造使其具备高压缩性,压缩率是碎石的10倍;陶粒可压缩层的让压效果要优于碎石可压缩层;不等压地应力条件下,碎石可压缩层会在一定程度上减小管片衬砌负弯区的抗力系数,导致负弯矩偏大,负弯区裂纹数量和宽度增加。陶粒和碎石的形状和内部构造差异导致两者让压效果和机制不同,最终导致管片衬砌的内力和变形、破坏特征差异。陶粒可压缩层让压机制由相互嵌挤、错动移位和挤压破碎作用三部分组成;碎石可压缩层的让压机制由前两部分组成;不等压地应力件下,由于陶粒的圆形形状特征,其向地应力较小侧自由移位和挤压作用发挥程度要高于菱角状外形的碎石,这一特征不仅增加了陶粒的让压效果还会在一定程度上增大了地应力较小侧的地层抗力系数,改善了管片衬砌受力特性。研究结果对未来TBM工法修建深部斜井的支护结构型式设计具有一定参考价值。Suitable for tunneling in deep stratum using TBM method, a yielding technology of segment lining combined with compressible ceramic is proposed. Based on the project of deep, long-distance inclined shaft engineering constructed by TBM method in Taigemiao Mine, model tests is used to study the yielding effects of ceramic and crushed stone compressible layer from the bending moment, axial force, deformation and failure characteristic of segment lining. The yielding mechanism is revealed according to the compressible deformation path and the moving characteristics of particles in compressible layers. The research results indicate that the honeycomb structure in ceramic can offer high compressibility, thus its compression rate is 10 times the crushed stone. The yielding effect of ceramic compressible layer is better than that of the crushed stone. Under unequal compressive stress, the crushed stone compressible layer would reduce the resistance coefficient in negative bending area of segment lining to a certain extent, causing larger negative bending moment and increasing the number and width of cracks in negative bending area. Due to different shape and internal structure, the ceramic and the crushed stone results have different yielding effects and mechanisms different, eventually leading to the difference of internal force, deformation and damage characteristics. The yielding mechanism of the ceramic compressible layer consists of mutual wedging action, dislocated displacement and squeezing break, while that of the crushed stone compressible layer only contain the first two parts. Due to the particle characteristic, the degree of ceramic moving to and extruding in area, where ground stress is smaller, is higher than the angular crushed stone under unequal compressive stress. Not only the yielding effects of ceramic is increased, but also the resistance coefficient in that area is enhanced, thus the mechanical properties of segment lining is improved. The research results can provide reference for the future des

关 键 词：深部围岩 TBM施工 管片衬砌 让压技术 陶粒可压缩层 模型试验 

分 类 号：TD353[矿业工程—矿井建设]