详情

Experimental investigation of tunnel squeezing problem in soft ground

项目名称：	Experimental investigation of tunnel squeezing problem in soft ground
摘要：	Ground squeezing resulting in large plastic zone and large convergence is one of the most challenging problems in tunneling. The squeezing problem in tunnels is often associated with high overburden, low compressive strength of geomaterial, tunnel excavation sequence, competency ratio, tangential strains or the mineralogy of the rock or soil. One or more factor(s) have been used in the literature to define problem of squeezing. Various empirical, semi-empirical and analytical correlations have been developed over the years, but many correlations are problem specific and contradicts with each other. In this work, an experiment will be designed that will study the squeezing problem in tunnel under soft ground conditions. The experimental will be performed on a cubical specimen of a soft rock/soil/synthetic material with a size of 30x30x30 cm�. The specimen will be subjected to compressive poly-axial stress state in all three directions, i.e. σ1>σ2>σ3. A small model earth pressure balance (EPB) tunnel boring machine (TBM) will be designed that can simulate excavation similar to real on site tunneling. Monitoring will be done using acoustic emission (AE), borehole extensometer, strain gages and accelerometers will be installed in TBM and on the cubical specimen. The critical conclusions and correlation developed from the experimental results will contribute significantly and will be give better insight into the problem of tunnel squeezing.
状态：	Active
资金：	330000
资助组织：	Office of the Assistant Secretary for Research and Technology
管理组织：	Colorado School of Mines
执行机构：	Colorado School of Mines
主要研究人员：	Hedayat , Ahmadreza
开始时间：	20170801
预计完成日期：	20191231
实际结束时间：	0