Study On The Deformation And Failure Mechanism Of U-shaped Subway Tunnel Across Ground Fissure With 40°

Ground fissure is a serious geological disaster, has the significant threat regarding humanity's daily life. In our country's old city Xi'an, crossed the urban district the place crack already to achieve 14, this regarding was being constructed the Xi'an subway is a stern test, regarding this, in the domestic and foreign subway project's construction history, has not constructed subway's precedent in this kind of location, did not have the ready-made standard regulations to be possible to follow.Therefore the research crack to the subway tunnel structure's action mechanism and the destruction pattern, chooses the reasonable lining work structure character, how discovers to guarantee that under the place crack function the lining work structure's overall stable method, has certain project significance to the Xi'an subway's construction. In order to study when the subway tunnel passes through the crack section, in the place crack activity's time stress pattern and periphery the soil body pressure's change form, uses the Chang An University's large-scale roadbed settlement test platform, has carried on the U-shaped subway tunnel structure traversing crack physical model experiment. May know by the test result, the crack activity to passes through the crack belt's integral-type tunnel structure area of influence mainly nearby the place crack the both sides, especially approaches the crack belt structure to under plate the influence to be biggest, the structure crown receives nearby the place crack belt pulls, base bearing.The cross crack's integral-type tunnel structure will prevent in structure crown certain scope the gneiss downward movement, but the structure both sides drop the soil body will produce to the structure crown's soil body downward tows entrains the function, this will increase the tunnel structure crown enormously the vertical adjacent formation pressure.In addition, carries on the numerical simulation using finite element software ANSYS to the U-shaped tunnel model,Numerical calculus's result and the physical model experiment's result carries on the comparison, finally demonstrated that its change rules and so on displacement, stress, strain have the uniformity.