超深地下连续墙槽壁稳定性分析与施工措施

根据土层的物理力学性质、承压水头及护壁泥浆等进行超深地下连续墙槽壁稳定性分析。通过槽壁稳定性解析理论与数值计算对比分析出安全系数，相应提出超深地下连续墙的施工泥浆护壁措施，防止槽壁坍塌。得出以下结论：1)当超深地层中存在多层承压水头时，应特别注意泥浆容重和液面高度的调整，确保槽壁稳定性；2)推荐施工中配置泥浆容重达到12.5kN/m3，采用导墙将泥浆液面提升1m，安全系数将达到1.4；3)施工过程证明，泥浆容重控制在11～13kN/m3时，能有效地保证槽壁的稳定性。

Analysis on Stability of Trench Walls of Extra-deep Diaphragm Walls and Countermeasures

The stability of the trench walls of extra-deep diaphragm walls is analyzed on basis of the physical and mechanical properties of the soil strata,the artesian water head and the wall-protection slurry.The safety coefficient of the trench walls is analyzed and provided on basis of analytical theory and numerical calculation of the stability of the trench walls.Countermeasures for the slurry protection of the trench walls of extra-deep diaphragm walls are proposed.The conclusions drawn are as follows： 1） Special attention should be paid to the adjustment of the unit weight and level of the slurry in case multiple layers of artesian water heads exist in the extra-deep strata;2） It is proposed that the unit weight of the slurry prepared during construction should reach 12.5 kN/m 3,the slurry level should be increased by 1 m by means of guide walls and the safety coefficient should reach 1.4;3） The construction practice shows that when the unit weight of the slurry is controlled to range from 11 kN/m 3 to 13 kN/m 3,the stability of the trench walls can be effectively guaranteed.