Numerical Analysis Of The Large Deformation Section Of No.3 Inclined Shaft Muzhailing Tunnel On Weiwu Expressway

As the number of cars in China,especially the number of privately owned cars,has surged,so has the number of roads and expressways needed for the driving of cars.In recent years,with the increase of floating population,expressway,as a relatively convenient and fast mode of transportation,has witnessed an increase in the construction mileage year by year.In this paper,the large deformation of soft rock tunnel is studied under the practical engineering background of muziling no.3 inclined shaft tunnel.As difficult point of the largest engineering nutrient-laden wu project river crossing was with China’s two big river watershed-wood village ridge village tunnel,the wooden village ridge,large slope deformation paragraph 3,is selected in this paper the actual engineering background.Wooden village ridge tunnel surrounding rock are mainly carbonaceous phyllite,carbonaceous SLATE,sandstone and loess,design level are Ⅴ weak rock,the initial supporting prone to large deformation,the permanent lining structure easy to crack.Combining with wooden village ridge slope engineering background,3 references predecessors about highway tunnel,soft rock tunnel,the numerical simulation results,according to the 3 slope initial design data in CAD drawing tunnel profile,import modeling in ANSYS,and the ANSYS modeling after the model of basic information into the node information and material assignment and the excavation is simulated in FLAC,then there can be no reinforcement measures of the comparative study on the numerical simulation results and the measured data.According to the design data after the design change,the model is established again,and the calculated results are compared with the unreinforced measures.Finally,the effect of strengthening measures on the deformation of tunnel is discussed,mainly whether the reinforcing ring is closed or not,and the effect of strengthening layer thickness on the deformation of tunnel is discussed.Through the above work,several conclusions are drawn in this paper:1.Wooden village ridge,the large deformation of the tunnel section of inclined well of the no.3 in the process of slope excavation,the early part of the paragraph with the increase of the supporting time,the deformation is not stable,some paragraphs or even produce crack,fall off,in the early part deformation area,cause serious deformation of steel arch shelf,including axial fold deformation along the tunnel and tunnel vertical axial distortion.While paying attention to the damage caused by the top settlement of the arch,it should also pay attention to the uplift deformation after the construction of the inverted arch,especially the cracking failure of the inverted arch after the delivery and operation.2.Based on the design change scheme of reinforcement measures in numerical simulation,find the reinforcement measures in the design scheme can very good control thedeformation of the surrounding rock,in the actual construction should strictly comply with the corresponding excavation steps.3.Based on the numerical simulation of the reinforced layer is a closed loop,it is concluded that when the reinforcement measures,closed loop reinforcing ring than half ring sealed reinforcement layer on the deformation of surrounding rock control effect is more obvious.To model the overall deformation strengthening positive half ring is 24.07 cm,and the hoop reinforcement is 13.59 cm,difference is 10.48 cm,the reinforced area for circular reinforced by strengthening closed half ring,model overall vertical uplift deformation in the inverted arch area reduced 43.54%;To model the overall deformation without negative reinforcement is 16.99 cm,and hoop reinforcement is 6.48 cm,difference is 10.51 cm,the reinforced area for circular reinforced by strengthening closed half ring,vertical deformation model as a whole in the central vault subsidence deformation reduced 61.86%.To model the overall deformation strengthening positive half ring is 24.54 cm,and the hoop reinforcement is 15.29 cm,difference is 9.25 cm,the reinforced area for circular reinforced by strengthening closed half ring,overall vertical in the inverted arch part of the overall model deformation decreased by 37.69%.4.Through the numerical simulation of different reinforcement layer thickness,it is concluded that in the tunnels for analyzing the results of numerical simulation of different working conditions,never take reinforcement measures,and the half ring to closed reinforcement measures,to the different thickness of reinforcement layer,inverted arch tunnel uplift deformation and vault subsidence deformation tend to decline,which from without reinforcement measures to half ring not closed reinforcement measures,the deformation value,the biggest change in the half ring not closed reinforcement measures to reinforce the 1.5 m thick,the vertical deformation values change.The influence of different thickness of reinforcement layer on deformation value is weak.In the reinforcement layer thickness increased from 1.5 m to 3.0 m in surrounding rock deformation is obviously better than the control effect of reinforcement layer thickness increased from 3.0 m to 4.5 m,though with the same thickness increase the gradient,but reinforcing layer thickness increased from 1.5 m to 3.0 m when the surrounding rock deformation control effect is more outstanding.However,this rule only applies to the target section,and whether it is applicable to other surrounding rock conditions and construction conditions remains to be further studied.