Numeric Simulation About Strike-slip Movement Of The Seismic Faults Resulting In Destructive Effect Of Qinghai-Xizang Railway

In this paper, on the basis of plentiful reference papers, the author introduce the feature ofseveral primary active faults in the northern, middle and southern region of the Qinghai-Xizangplateau and space-time distribute characteristics about earthquake activity in the Qinghai-Xizangplateau simply, especially the Kunlun active faults and the 2001 Ms 8.1 Kunlun earthquake.Thennumeric simulation about strike-slip movement of the seismic faults resulting in destructive effectof Qinghai-Xizang railway is brought into effect in virture of common analysis software ofANSYS, taking Kunlun active fault as an example. Some research results and cognition areobtained as follows:(1) In the northern area of Qinghai-Tibet Plateau, there are some left-lateral strike-slipmovement faults, such as Altyn fault, Haiyuan fault and so on. Its average slip-rate is 10～15mm/a. The Eastern Kunlun Fault's average slip-rate is 10～12mm/a nowadays, In the southernregion, there are right-lateral strike-slip movement faults, such as jiali fault, Red river fault, itsaverage slip-rate is 5～15mm/a. West Datan Fault have 3 ancient earthquake incident in earlyHolecene, the magnitude of these 3 earthquakes is Ms7.6, Ms 7.6, Ms 7.3. The correspondinghorizontal displacement is 9m, 9m, 4m..(2)The general geological and geometrical model is established by understanding geometricaland kinematic characteristics of The Eastern Kunlun Fault well. The model is composed ofbedrock, quaternary soil, groundsill, concrete crosstie and rail. The fault belt divide the model intotwo parts: southern block and northern block. Restrict condition of model boundary and loadapplying are confirmed, i.e, northern block is restricted and initial eastward displacement is put onthe west side of the southern block(3)this paper stimulate two deformation effect (the epicenter is located near the railway orfar away it) when the earthquake with 3m and 8m level left-lateral displacement, respectively.The result shows that the southern bedrock and quaternary of the EKF have 3m left-lateralstrike-slip displacement when epicenter is located far away the railway. However, the leveldiaplacement of quaternary near the railway is smaller, rail and groundsill show successiveleft-lateral crooked deformation. It have just 1～2 m successive left-lateral crooked deformation; Two sides of the railway cause the N-E direction tensile opening and N-W direction earthquakeapophysis, the distortion has taken place in the rail near the falut belt. Deformation effect issimilar when epicenter is located near the railway, but the extent of displacement is more terrible, and the rail and groundsill have the 4～5m successive left-lateral crooked deformation, and thestress level of the rail is 2.5 times as high as that of the former situation, . And, the distortion ofthe rail is more terrible.Therefore, the great earthquake induced by EKF in the future will resultin great deformation and destruction of Qinghai-Lahsa railway whether epicenter is located nearthe railway or not.(4)After Analyzing the stability of the railway engineering According to the result of stressand displacement, some suggestion are put forward for construction of railway engineering withwidening groundsill, replaceing soil layer, reducing the space between crosstie near the fault beltand so on.