Comparative study on lateral dynamic response characteristics of straight inclined group piles in dry sand and saturated sand site
The lateral dynamic response of group pile foundation has been a hot issue in the field of geotechnical engineering seismic research.In this regard,the centrifuge shaking table test of 2×2 straight-sloping group pile under dry sand and saturated sand site conditions is carried out,then a three-dimensional numerical model is established based on the introduction of sand soil liquefaction large deformation ontology by FLAC3D software,and the test results are compared with the numerical simulation results for verification.The transverse dynamic response rule of straight inclined pilegroup in test and simulation is deeply analyzed.The results show that in dry sand site,the acceleration of straight group pile bearing is always larger than that of inclined group pile bearing.In saturated sand site,the acceleration of both straight and inclined group pile bearing decays to a certain extent,but the decay of acceleration of straight group pile bearing is more obvious than that of inclined group pile bearing.The pile bending moment decreases with the increase of pile spacing in dry sand site,and the pile bending moment increases with the increase of pile spacing in saturated sand site.The pile bending moment in the dry sand site decreases with increasing pile spacing,while the pile bending moment in the saturated sand site increases with increasing pile spacing and then decreases.The required pile spacing is greater for dry sand sites where the amplification of the bearing acceleration with respect to the input table acceleration is less than 1 for saturated sand sites.