Analysis On The Influence Of Weak Interlayer On Seismic Dynamic Response Of Slope In Tianshui Area

Weak intercalation is a weak and thin layer in rock and soil,which has great influence on dynamic stability of slope due to its low strength.In this paper,the slope of tianshuijihe river basin,where there are many weak interb-edded layers,is selected to calculate the physical parameters and geometric f orms of the typical slope in this area,and the numerical model of typical slo-pe in tianshui area is designed.The physical parameters and geometric parameters of the typical soft interlayer of slope in this area were calculated,and the reasonable variation range of the parameters of the soft interlayer was det ermined.Based on the principle of orthogonal experiment,the effect of weak interlayer parameters on the seismic dynamic response of slope in tianshui a rea was studied.This paper study the effect of weak intercalations slope dynamic response to the earthquake,mainly divided into two aspects,one is the typical slope dynamic response on the research of the soft interlayer parameters sensitivity,the second is the weak interlayer occurrence on the slope and the plastic zo-ne distribution of space distribution of seismic energy.The specific work is as follows:(1)under the weak earthquake excitation,the choice of weak intercalations density,young's modulus,poisson ratio,damping ratio,Angle,depth and thickness of the seven factors,select Z to maximum speed as dynamic response e-valuation indicators,analysis the influence of parameters on the ty pical slope weak shaking force response.The sensitivity ranking of the param eters of weak interlayer was obtained by using the difference analysis method: > young's-modulus > inclination > poisson depth > density > thickness.Th e variation rule of evaluation index is analyzed when the variation within the single fac-tor range of weak interlayer is analyzed.Under strong earthquake excitation,choose soft interlayer cohesion,internal friction Angle,damping ratio,Angle,depth,thickness of 6 factors,select the critical acceleration as the dynamic stability evaluation index,the earthquake dynamic response analysis of various parameters on the typical slope and the effect of using the method of poor,weak inter-layer parameter sensitivity sequence is: the damping ratio > cohesion > Angle of internal friction Angle of deep thickness > Single fa ctor analysis was carried out on the parameters of weak inter-layer,and the v ariation rule of evaluation indexes was summarized.According to the analysis met-hod of variance F value,the sensitivity of each factor is analyzed,and the cohesion is very sensitive.The internal friction Angle,damping ratio and inclination Angle are sensitive,and the depth and thickness are not sensitive.(2)the typical slope under the action of vertical incident p wave excitation,observe the occurrence of slope with different weak inter-calated in wave fiel d space distribution,according to the occurrence,Neil's law,analysis of weak inter-calations of the influence of the spatial distribution of seismic energy,g et the following rules:The change of the slope Angle of the weak inter-layer will lead to the chang e of the maximum energy concentration position of the slope.The energy acc u-mulation in a side slope containing a cis inclined soft interlayer increases with the increase of the inclination Angle of the weak interlayer.With the in crease of the dip Angle of the weak interlayer,the energy accumulation in th e slope decreases.With the increase of the dip Angle of the weak interlayer,the energy concentration of the top of the slope reaches the extreme value when the soft interlayer is formed along the slope foot.As the depth of the weak interlayer increases,the energy accumulation in the slope decreases.Wit h the increase of weak interlayer thickness,the energy accumulation in slope decreases.(3)the typical slope under the effect of vertical incident p-wave excitation,th e weak intercalations occurrence on the slope the influence law of the plastic zone distribution is as follows:(1)soft interlayer attitude determines the plas ticity through the form;Affect the plastic type,(2)the weak intercalated with weak interlayer depth increases,the slope by mainly mainly shear failure to shear failure and tensile damage coexist,and pull destroy focused on slope w ith weak interlayer interchange.