基于组合块体集的浅埋条形锚板上限分析

 基于极限分析法的基本原理以及集成与组合的思路，推导组合块体集的内能耗散和重力做功，运用组合的思想构造斜坡地形下浅埋水平条形锚板的运动许可速度场。首先分析地表水平条件下法向受力水平条形锚板抗拔承载力，并与文献中已有解和模型试验进行对比，验证块体集上限法的优越性。然后详细研究斜坡地形条件下土体重度、不排水抗剪强度、斜坡倾角等因素对条形锚板抗拔承载力和破坏面形状的影响。分析结果表明：重力叠加法并不适用于斜坡地形情况；随着斜坡倾角的增大，锚板的破坏面向坡角方向倾斜；锚板埋深比越大，斜坡倾角的影响也越显著。块体集上限分析方法构造简单，求解快捷，能够为工程设计提供依据。

UPPER BOUND ANALYSIS OF HORIZONTALLY EMBEDDED ANCHORS BASED ON BLOCK SET MECHANISM

Based on the bound theorems of limit analysis，admissible velocity field of horizontal strip anchor is constructed by using a combination of several rotational block sets. An application to upper bound analysis of vertically loaded strip anchors on horizontal ground surface is given first to illustrate the utility and effectiveness of the proposed method，and include detailed comparisons with results obtained from other approaches. Then the pull-out capacities of strip anchors in undrained clay with sloping ground surface are analyzed. Pull-out capacity and failure surface characteristics under different embedment ratios，undrained strength，inclined angles of slopes and weight of soil are studied. The results show that the superposition of gravity is not applicable to the case of sloping ground surface. The variation of slope angle has a significant impact on failure surface. The block set mechanism is based on a very simple concept which is integration and combination and can be a reference for the practical design.