Study On Supporting Structure Of Highway Tunnel With Soft Surrounding Rock

Up to now, the soft surrounding rock tunnel supporting parameters is still a difficult problem in engineering.There is no mature theory at home and abroad. Examples of accidents in the construction process are common due to inadequate analysis of rock mechanics properties and deformation characteristics of soft surrounding rock. Based on the Guang-Gan highway tunnels the paper studied the soft surrounding tunnels to provided reference for the similar engineering.At frist,in this thesis, a lot of statistical research and example analysis of the existing soft surrounding tunnel at home and abroad were implemented.The author give out a preliminary evaluation of supporting parameters with those soft surrounding tunnel.The research relied on Guang-Gan Highway tunnel groups. Based on a comprehensive research about the key technology of designing and constructing soft surrounding rock at home and abroad, combined with the general engineering geology situation and supporting parameters, monitoring data were adopted for analysis. The author analyzed the rationality of actual supporting effect about the support parameters selected in the tunnel around the meizoseismal area according to multi-information. The case analysis of some typical soft surrounding tunnel in Guang-Gan highway or other regions at home and abroad was done.The author also carried out a thorough research on the supporting parameters of the rock in the soft surrounding rock area by adopting numerical simulation and model test, so as to evaluate the stability and security of the tunnel support structure in various kinds of conditions, and then brought in reasonable Support measures.In order to explore supporting parameter problem of the soft surrounding rock tunnel with soft phyllite as the representative,a20m test section was set up in Dujiashan tunnel.The author also researched the supporting structure,s internal force and deformation through the field monitoring and measurement.The test provided the most valuable field date for soft surrounding rock tunnel support parameter optimizationThorough research was done to supporting parameters of soft surrounding rock in static state by numberical simulation and indoor model test.The author evaluated the stability and safety of tunnel supporting structure in different engineering situation.and then put forward reasonable supporting measures.