Research On The Construction Stability Of Large Section Tunnel About HongQiHeGou Station On 6~th Line Of Light Rail In ChongQing

This article relies on the tunnel engineering of the station Chongqing light rail line 6 red flag, briefly introduces the general situation of the station tunnel, comprehensive analysis the numerical simulation of the dynamic construction of the process of the subway tunnel and the secondary lining safety analysis the present research situation and realization method. This article analysis the transmutation rule of the strata and its supporting structure, points out the construction process of wallrock deformation trend, the stress properties of the primary support and analyzed the long-term stability of the second lining, further more to introduces the excavation blasting process taken in blasting scheme and blasting parameters in detail, and surrounding rock bolting and monitor measuring key for tunnel construction, in order to sent this warning information for the construction of tunnel, convenient for choosing the reasonable method of excavation and supporting, guidance for engineering construction. The main conclusions are as follows:①The station tunnel project of Hongqihegou of the light rail line 6 is used a series of construction techniques including: advanced small catheter supporting, spray anchor bracing, steel arch frame system, and temporary support of applied, two lining construction and lining behind grouting and so on. The tunneling method of surrounding rock, protection of surrounding rock, playing the role of the self-supporting have paid more attention to.②Using large-scale finite element analysis software named ANSYS10.0 respectively on the double meshshotcreting firstly method and CD method on the numerical simulation, after the detailed analysis of the two kinds of method in construction process, supporting structure of the stress distribution characteristics, surface and vault settlement differences, the distribution area of the rock body strain, it is concluded that the theory of line 6 red flag into the station excavation the most appropriate method, i.e. use next door method is feasible, but it must be closely combining the construction process of the monitoring. In the 2d finite element simulation, this method was satisfied in the security and the stability of construction requirements. ③Using finite element analysis software for a station large cross-section tunnel in the second lining is simulated calculation indicates that the second lining structure of plot, shaft tries to. Obtained that the junction of the sidewall and Yang arch appeared the most-positive bending moment, have stress concentration phenomenon. Invert the maximum negative moment at the bear, both of which are prone to damage the site.④This blasting compiled the reasonable blasting scheme, in damping measures are: hole body adding damping hole, a peripheral plum flower form decorate; Peripheral eye using decouple medicine; Reasonable choice of subsection and time interval.⑤In the process of the construction, vault sink, horizontal convergence, surface subsidence these specificly displays in: the excavation around the drift influences each other, namely hole-hole effect production; The core of soil excavation had a negative effects to the stability of the entire tunnel structure.