考虑土体分层性质,假定开挖槽段附近各土层厚度分布均匀且土层分界面垂直于槽面,以经典二维楔形滑块体模型为研究对象,提出了地下连续墙泥浆护壁稳定性评价的水平条分法,建立了满足条块力平衡的3M方程评价模型和同时满足力平衡和力矩平衡的4M方程评价模型,提出了求解方法,并验证了3M方程模型的有效性和条分法提出的必要性.将3M评价模型应用于武汉市某超深基坑成槽开挖坍塌的槽段稳定性分析,总结了临界角度和安全系数随地下水位、地表超载、泥浆高差、及泥浆重度的变化规律.最后用定义的水平条间力与竖向条间力的比值讨论了不同参数取值下水平条间力的变化规律.

The existing studies indicate that the shear stress between grout body and rock mass along the anchoring segment of a prestressed anchor is not uniform. The non-uniform shear stress design method is one of the development trends for prestressed anchor design, but the current design methods still treat the shear stress as uniform one. The reason lies in that widely recognized shear stress distribution pattern and formula have not been established. However, the bearing capacity of pressure-dispersive anchors is much higher than that of the tension ones, which means that the shear stress between grout body and rock mass in anchoring segment is more concentrated. So the non-uniform shear stress design method is more necessary to pressure-dispersive anchor. Three indoor full size simulating experiments are undertaken to get the shear stress, and multi-factor numerical simulations are done to discover distribution characters of the shear stress. Two distribution patterns are drawn from the indoor tests and calculations, and key parameters of the shear stress distribution curves are confirmed through the numerical caIculations. Equation derivations are done based on the two distribution patterns, and a non-uniform shear stress design method of pressure-dispersive anchor is finally established. It is proved that the proposed method agrees with the indoor experiments and numerical simulations.

The construction of ten adjacent panels of a diaphragm wall of an ultra deep excavation in Wuhan city is simulated by a three-dimensional finite difference method. The construction procedure consists of the excavation supported by slurry, concrete pouring, and concrete hardening. The excavation is simulated by the constant distributed hydrostatic pressure while the concrete pouring process adopts variable distributed hydrostatic pressure. The concrete hardening process is finished by linear elastic solid elements with variable elasticity modulus and Poisson ratio. The results of the numerical computation show good agreement with the field test data. According to the process of single jumping excavation, the pressure monitoring reveals the influence of diaphragm wall construction on stress redistribution. The earth pressure fluctuates along the retaining wall after the construction completion of the ten panels. The peak value appears in the middle of the panel, while the trough value appears around the junction of two panels. The fluctuation range is related to the depth. The differences between slurry pressure, concrete pouring pressure and earth pressure are the main reason influencing the redistribution of earth pressure. Reasonable slurry unit weight and ideal concrete pouring method are suggested to avoid disturbance of soils.

合成出一种有机硼酸酯,含有羟甲基化苯并三氮唑和油酸二乙醇酰胺硼酸酯的特征基团.采用失重法、防锈试验方法测定了其防腐蚀及防锈性能.并采用四球摩擦磨损试验法、圆环法测定其润滑性与清洗性.在改变添加剂添加量、实验温度、实验时间的条件下探讨这些因素对切削液性能的影响.结果表明,在合成产物的质量分数添加量为0.25％时,各项性能测试情况良好,在较高温度及较长时间的连续工作情况下仍保持优良的防锈性能,可用作水基切削液中常用的防锈润滑添加剂.