墙背摩擦力对坞式船闸底板影响及其改善措施

The influence of friction between wall back and soil on the stress in ship-lock floors and its improvement measures

软基上的船闸底板中部经常会在墙后土体回填施工过程中出现纵向裂缝,常规方法无法解释。本文建立有限元仿真模型,模拟混凝土浇筑、土体回填等施工过程,以及土体固结过程,分析墙背有无摩擦力的差别,指出摩擦力对底板受力存在较大影响,增加了常规计算的误差,是引起底板开裂的重要原因之一,建议引起足够重视,并建议根据地基类型和工程重要性采取合适措施进行防范和改善。

The cause of longitudinal cracks on ship-lock surface during soil backfilling cannot be explained by conventional design methods. A finite element method （FEM） model is established to simulate the construction process of ship-lock and the soil consolidation process, and the behaviors of floor surface stress are analyzed for two cases, considering or neglecting the friction between the wall back and backfilled soil. It is concluded that this friction as an important cause for the cracks, has a great influence on the floor stress and it may lead to a significant error in the results of conventional design method. Finally, it is proposed that enough attention should be put on the friction and certain construction measures should be taken to avoid and at least to control the fiction according to the foundation type and importance of ship-lock.