In this study,2D and 3D soil arching phenomena associated with piled embankments were evaluated by performing a series of discrete numerical analyses using the particle flow code(PFC3D)software.After validating the mi...In this study,2D and 3D soil arching phenomena associated with piled embankments were evaluated by performing a series of discrete numerical analyses using the particle flow code(PFC3D)software.After validating the micro-parameters with experimental results,we compared the stress-displacement distribution,force chain evolution,maximum vertical displacement of particles,and deformation characteristics induced by 2D and 3D arching effects.Additional analyses were carried out to understand the influence of the fill height,pile clear spacing,friction coefficient,and porosity on soil arching with respect to the stress concentration ratio(SCR)and settlement along the elevation at various sections.The numerical results indicated that a plane soil arch in a 2D embankment overestimates the degree of load transfer and underestimates the settlement at the crest and within the embankment along the elevation in a 3D embankment.A lower equal settlement plane can be found in a 2D embankment.Furthermore,an increase of fill height and friction angle,and a decrease of pile clear spacing and porosity can help to improve the degree of reduction in load transfer and settlement in both 2D and 3D embankments.However,for partially mobilized soil arching in the 3D condition,the increase of fill height reduces the settlement of soils mainly in the portion above the square subsoil area,but has less influence over the portion above the rectangular subsoil area.展开更多
被动桩对侧向位移的土层起到遮拦作用的机制主要是土拱效应。采用土工有限元软件Plaxis Tunnel 3D 1.2,对堆载荷载作用下邻近桩基中的土拱效应产生机制和性状进行三维数值分析,指出目前被动桩中土拱效应二维有限元分析存在的问题。考虑...被动桩对侧向位移的土层起到遮拦作用的机制主要是土拱效应。采用土工有限元软件Plaxis Tunnel 3D 1.2,对堆载荷载作用下邻近桩基中的土拱效应产生机制和性状进行三维数值分析,指出目前被动桩中土拱效应二维有限元分析存在的问题。考虑桩土侧移与相对位移,再利用土工有限元软件Plaxis2D 8.2详细地研究了侧向土体位移大小、桩身水平位移大小、土体性质以及桩土接触面性质等影响因素对土拱效应性态和桩土荷载分担比的影响。展开更多
基金Project supported by the National Natural Science Foundation of China(No.41772289)。
文摘In this study,2D and 3D soil arching phenomena associated with piled embankments were evaluated by performing a series of discrete numerical analyses using the particle flow code(PFC3D)software.After validating the micro-parameters with experimental results,we compared the stress-displacement distribution,force chain evolution,maximum vertical displacement of particles,and deformation characteristics induced by 2D and 3D arching effects.Additional analyses were carried out to understand the influence of the fill height,pile clear spacing,friction coefficient,and porosity on soil arching with respect to the stress concentration ratio(SCR)and settlement along the elevation at various sections.The numerical results indicated that a plane soil arch in a 2D embankment overestimates the degree of load transfer and underestimates the settlement at the crest and within the embankment along the elevation in a 3D embankment.A lower equal settlement plane can be found in a 2D embankment.Furthermore,an increase of fill height and friction angle,and a decrease of pile clear spacing and porosity can help to improve the degree of reduction in load transfer and settlement in both 2D and 3D embankments.However,for partially mobilized soil arching in the 3D condition,the increase of fill height reduces the settlement of soils mainly in the portion above the square subsoil area,but has less influence over the portion above the rectangular subsoil area.
文摘被动桩对侧向位移的土层起到遮拦作用的机制主要是土拱效应。采用土工有限元软件Plaxis Tunnel 3D 1.2,对堆载荷载作用下邻近桩基中的土拱效应产生机制和性状进行三维数值分析,指出目前被动桩中土拱效应二维有限元分析存在的问题。考虑桩土侧移与相对位移,再利用土工有限元软件Plaxis2D 8.2详细地研究了侧向土体位移大小、桩身水平位移大小、土体性质以及桩土接触面性质等影响因素对土拱效应性态和桩土荷载分担比的影响。