Mitigation Of Liquefaction-Induced Lateral Deformation In A Slightly Sloping Stratum By Gravel Pile In Open Sees

A large number of earthquakes indicate that the lateral deformation triggered by the liquefaction of the sloping ground will cause damage to the building,causing the building to lose some or all of its functions,resulting in a large number of casualties and property losses.The use of gravel pile treatment method can effectively alleviate the earthquake disaster,and explore the effect of gravel pile on sloping ground treatment,which not only has certain scientific value,but also provides guidance for foundation treatment design.Based on the numerical simulation research method of OpenSees,this paper studies the treatment effect of sloping ground with different displacement rates by changing the amplitude and spectral characteristics of ground motion.Mainly carried out the following work:Firstly,the damage caused by the Lateral deformation of the sloping ground is introduced.The research status of the sloping ground treated by gravel pile is reviewed from the aspects of the mechanism and influencing factors of the liquefaction site.Secondly,the numerical simulation method of OpenSees finite element software is briefly introduced.The constitutive relation of PDMY02 material and the conversion method of permeability coefficient used in this paper are introduced in detail,which lays a foundation for the subsequent research work.Thirdly,by selecting reasonable pile unit,soil unit and soil constitutive model,OpenSees software was used to numerically simulate the gravel piles with differentdisplacement rates to treat the sloping ground,and the displacement rate was analyzed and simulated to let us know the impact of site treatment effects.Fourthly,the effects of ground motion peak and spectral characteristics on the effect of gravel pile treatment on sloping ground are studied.The results show that the ground motion peak and spectral characteristics have an effect on the Lateral deformation of the sloping ground.The larger the PGA is,the longer the effective holding time is.The closer the ground motion spectrum characteristics are to the site jailbreak cycle,the more obvious the liquefaction phenomenon of the site.The larger the lateral deformation of the sloping ground,the more significant the treatment effect.Finally,this paper summarizes the research work and looks forward to the future research work.