Pseudo-Static Test And Seismic Performance Of Slope Rock-Socketed Single Pile With Vertical Load

China's land resources are increasingly scarce,in order to meet the needs of construction,often the building built on the slope,such projects will inevitably build the pile foundation in the slope,the formation of slope pile foundation.The mechanical characteristics of slope pile foundation are more complex than that of plain pile foundation.At present,the research on slope pile foundation is not mature enough,and the research on the seismic performance of rock-socketed pile is rare.Combined with practical engineering,this paper selected the area and the upper structure of the prototype,according to the similarity theory,completed the study the design of the scale model,has chosen to satisfy the pile,the similarity relation of material for the foundation,to make a batch of model box and a convenient loading and can be repeated use of loading first,has carried out three groups of pseudo static test,studied the slope Angle,the pile rock elastic modulus than single rock-socketed pile body internal force of slope,bearing capacity,ductility performance,etc.The influence of the seismic performance indicators.The finite element model was established by ABAQUS software,and the validity of the analysis model was verified by comparing with the experimental results.According to the numerical analysis method,the influence of slope inclination Angle and axial compression ratio on the seismic performance of rock-socketed single pile is further analyzed and studied by changing slope inclination Angle and axial compression ratio.The conclusions of this paper are as follows:(1)It can be seen from the test phenomenon that,under the action of low cyclic load,with the increase of displacement,the rock mass is pushed away,and the void section is produced between the pile and rock mass.In front of the pile,the rock mass presents an obvious spindle-shaped cracking failure area,and behind the pile,the rock mass presents an obvious arching uplift.The failure degree of the model pile increases with the increase of the elastic modulus ratio of pile to rock,but the failure pattern is similar.The shear failure occurs at the interface of steel pipe and the reinforcement is broken.(2)According to the test results,for the model pile: 1)Under the action of downslope displacement,the strain and bending moment are always larger than those under the action of uphill displacement;2)The greater the rock mass stiffness,the greater the pile strain,bending moment and pile-rock pressure under the same displacement;3)When the depth is above 2D,the strain,bending moment and pile-rock pressure of the model pile change most obviously.With the increase of the depth,the readings decrease sharply.When the depth is below 4D,the readings can be ignored.4)The reaction force at the pile bottom does not exceed 10% of the load at the pile top,and the pile lateral friction resistance bears most of the vertical load.(3)According to the test results,for pile-rock system: 1)the shape of the hysteretic curve is shuttle shape under the action of small displacement,and it is "Z" shape when the displacement is large.2)The shape of the hysteretic curve is not symmetrical,and the asymmetry of the hysteretic curve increases obviously with the increase of the slope;3)With the increase of the elastic modulus of rock mass,the bearing capacity of pile-rock system is increased and the ductility is obviously reduced.As the slope slope decreases,the bearing capacity of pile-rock system decreases,and the ductility increases slightly.(4)The simulation results show that: 1)with the increase of slope inclination,the asymmetry of the hysteretic curve of rock-soaketed single pile increases obviously,the peak load increases obviously,and the ductility decreases somewhat;2)When the axial compression ratio of rock-socketed single pile is 0 and 0.23,the peak load has little difference,and when the axial compression ratio is 0.5,the peak load decreases obviously.3)When the axial compression ratio is from 0 to 0.23 to 0.5,the ductility of single rock-socketed pile with vertical load increases first and then decreases.