摘要
根据已有的平面应变试验数据,拟合得到了内摩擦角的各向异性变化曲线以及剪胀角与围压、相对密度的关系,并基于此来模拟在各向异性土中的沉桩过程。分析了沉桩过程中桩周土体的位移、应力、主应力及塑性区分布情况,并和土体各向同性条件下的模拟结果进行了比较。结果表明:沉桩结束后,桩身周围土体处于屈服状态,远离桩身的土体处于弹性状态;桩身周围土体位移向上,具有明显的挤土效应;只有小部分土体的滑动摩擦角达到了峰值内摩擦角,绝大部分土体的滑动摩擦角都小于峰值内摩擦角;土各向异性条件下的模拟结果与各向同性条件下具有一定差异,土各向异性条件下得到的竖直位移、竖直应力和水平应力相对于各向同性整体上较小。
Based on the existing plane strain test data,the relationship between mobilized internal friction angle and axial strain in different loading directions as well as the relationship between dilatancy angle and confining pressure and relative density are obtained,which are used to simulate pile sinking in anisotropic soil. The displacement,stress,principal stress and the plastic zone of the soil around the pile during pile driving are analyzed. In addition,the simulation results in anisotropic soil are compared with that in isotropic soil. Numerical simulation results indicate: The soil around the pile yield after pile sinking,but the soil away from the pile is elastic; there is an apparent compaction effect in pile sinking process.The mobilized internal friction angle of the soil reached the peak internal friction angle only in a small part of soil body,and that of others were less than their peak internal friction angle. The vertical displacement,vertical stress and horizontal stress obtained in anisotropic soil are less than that in isotropic soil.
出处
《施工技术》
CAS
2018年第S1期165-170,共6页
Construction Technology
关键词
各向异性
沉桩
数值模拟
剪胀角
anisotropy
pile sinking
simulation
dilatancy angle
