Study on Construction Technology of Drilling and Blasting Tunnel Passing Through Existing Twin-arch Tunnel
The drilling and blasting tunnel crosses the newly built existing double-arch tunnel structure.The subway is a large span tunnel,with a large height and deep burial,and when crossing the existing tunnel,it cannot affect its safe operation and structural damage,the construction is difficult.A numerical simulation was carried out using the finite element software Midas GTS NX to calculate the deformation and stresses of a drilling and blasting tunnel underpassing an existing tunnel,and to study the effect of the combined reinforcement of the inter-tunnel strata above using large pipe sheds and anchors before the underpass construction.Studies have shown that the settlement of the tunnel structure on the construction side is greater than on the other side when it is not reinforced,showing a"peak and two valleys"deformation shape,which makes the upper and lower parts of the existing tunnel very vulnerable to structural damage.The combined reinforcement with large pipe sheds and anchors effectively shifted the stress concentration phenomenon and reduced the risk of structural damage,and the settlement in the existing tunnel was only 1/1.83 of the former variation,within the control standard of 10mm.
tunnelsdrilling and blasting methodtwin-arch tunnelssimulationreinforcementfinite element analysis
万方数据
维普
