Abstract
Assessment on the stability of a tunnel surrounding rock mass is an important issue during designing and construction of the tunnel. There is still no good enough analytical method to calculate the displacement criterion on the stability of the tunnel surrounding rock mass due to its multifactors dominated. In this paper, an innovative method to achieve the assessment displacement criterion, based on elastoplastic theory, is formed by considering multifactors, such as the quality of surrounding rock mass, initial stress, tunnel size, and supporting system. The calculation formula in this method is deduced by taking into consideration of combination the displacement and plastic region of surrounding rock mass and the reinforcement zone by systemic bolt, based on the equilibrium in elastic region, plastic region, and border between elastic region and plastic region. Furthermore, the influence of critical factors on the displacement criterion, such as deformation property and strength property of surrounding rock mass, tunnel size, and tunnel overburden, is discussed to make it clear that how these factors affect the stability of the tunnel surrounding rock mass. The validity of the analytical calculation method is testified by the application in the Zipingpu tunnel engineering.
Highlights
Assessment on the stability of a tunnel surrounding rock mass is an important issue during designing and construction of the tunnel. ere is still no good enough analytical method to calculate the displacement criterion on the stability of the tunnel surrounding rock mass due to its multifactors dominated
The influence of critical factors on the displacement criterion, such as deformation property and strength property of surrounding rock mass, tunnel size, and tunnel overburden, is discussed to make it clear that how these factors affect the stability of the tunnel surrounding rock mass. e validity of the analytical calculation method is testified by the application in the Zipingpu tunnel engineering
Plastic region, tensile region, damaged region, maximum tensile stress, and displacement of tunnel surrounding rock mass are usually used as the stability index of tunnel surrounding rock mass [9–11], but some of indexes are difficult to obtain around tunnel during construction phase, such as plastic region, maximum tensile stress, and strain. e displacement of tunnel surrounding rock mass, which is easy relative to monitor on construction site by traditional monitoring method or last noncontact method, is selected as the index of tunnel surrounding rock stability [12–14]
Summary
Assessment on the stability of a tunnel surrounding rock mass is an important issue during designing and construction of the tunnel. ere is still no good enough analytical method to calculate the displacement criterion on the stability of the tunnel surrounding rock mass due to its multifactors dominated. An innovative method to achieve the assessment displacement criterion, based on elastoplastic theory, is formed by considering multifactors, such as the quality of surrounding rock mass, initial stress, tunnel size, and supporting system. 1. Introduction e evaluation of surrounding rock stability is always one of the most crucial issues in tunnel engineering, especially in design and construction phase. A new kind of analytical method on the stability analysis of tunnel is developed, and the new analytical method to calculate the displacement criterion is deduced based on the elastic and plastic theory, by consideration of the quality of tunnel surrounding rock mass, initial ground stress, tunnel size, and supporting system for tunnel. Plastic region, tensile region, damaged region, maximum tensile stress, and displacement of tunnel surrounding rock mass are usually used as the stability index of tunnel surrounding rock mass [9–11], but some of indexes are difficult to obtain around tunnel during construction phase, such as plastic region, maximum tensile stress, and strain. e displacement of tunnel surrounding rock mass, which is easy relative to monitor on construction site by traditional monitoring method or last noncontact method, is selected as the index of tunnel surrounding rock stability [12–14]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
