摘要
采用Abaqus软件中CEL技术对平板锚旋转安装特性及土体流动趋势进行大变形有限元分析。通过比较大变形有限元分析结果与已有的模型试验结果,取得了较好的一致性。有限元建模研究不同参数下平板锚的旋转安装特性,得出以下结论:从局部土体流动趋势,可以发现平板锚旋转安装过程变化规律;对于不同锚链-海平面夹角,仅考虑竖向荷载时,平板锚在90°方向拉出时竖向拉力最大,同时平板锚的埋深损失也最大;当锚眼偏心比较小时,平板锚的埋深损失非常大,且埋深损失主要集中在平板锚转至45°之前;土-锚摩擦系数α>0.5时,平板锚的埋深损失变化较小。
In this paper,a large deformation finite element analysis based on the CEL technique is conducted to simulate the keying process of plate anchors. Prior to parametric study,the large deformation finite element analysis results are validated against with centrifuge model test data,with good agreement obtained. From local soil flow mechanism,it can be found that the keying process of plate anchors is changed. For different chain-sea level angle,the vertical load is the maximum value when the plate anchors are pulling at 90 degrees. At the same time,loss of embedment of plate anchors is also the largest. When the anchor eye eccentricity ratio is relatively small,the loss of embedment of plate anchors is very large,and which is mainly concentrated in the plate anchors rotated to 45 degrees. When the soil-anchors friction coefficient large than 0.5,the loss of embedment of the plate anchors varies little.
引文
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