上覆CRSS快速固化淤泥硬壳层厚度对淤泥地基承载特性的影响

复合型早强土壤固化剂（CRSS）具有快凝高强特性，利用自主研发的CRSS固化剂对表层淤泥快速固化并作为上覆硬壳层，通过模型试验研究不同上覆硬壳层厚度（3、6、9、12 cm）条件下硬壳层破坏形式、p-s曲线特性、弯沉盆形状以及土压力分布规律，在现有弯沉盆变形理论基础上，结合试验结果，对弯沉盆变形形状函数进行修正。研究结果表明：随硬壳层厚度增大，硬壳层破坏形式由对折破坏过渡到冲切破坏；硬壳层厚度越大，扩散作用越明显，极限承载力越高，沉降相应增大；与荷载板中心点不同距离的沉降位移可用弯沉盆形状描述，提出了修正的对数弯沉盆假设变形计算公式，比线性弯沉盆假设变形计算公式更合理；土压力从中心向外呈下降趋势，沿深度方向逐渐减小；随硬壳层厚度增大，土压力分布更均匀。

Influence of the thickness of the overlying CRSS rapid solidifying sludge hard shell layer on the bearing characteristics of sludge foundations

The composite early strength soil stabilizer (CRSS) has the characteristics of rapid setting and high strength. The independently developed CRSS stabilizer is used to rapidly solidify the surface sludge as the overlying hard shell layer. Through model tests, the failure mode of the hard shell layer, p-s curve characteristics, the shape of the deflection basin and the distribution law of soil pressure under different overlying hard shell layer thicknesses (3 cm, 6 cm, 9 cm and 12 cm) are studied. On the basis of the existing deformation theory of the deflection basin, combined with the test results, deformation shape function of the deflection basin is modified. The results show that with increase of the thickness of the hard shell, the failure mode of the hard shell transits from folding failure to punching failure; The greater the thickness of the hard shell, the more obvious the diffusion effect, and the higher the ultimate bearing capacity, as well as the corresponding increase in settlement; the settlement displacement at different distances from the central point of the load plate can be described by the shape of the deflection basin. A modified formula for calculating the assumed deformation of the logarithmic deflection basin is proposed, which is more reasonable than the formula for calculating the assumed deformation of the linear deflection basin; the earth pressure decreases from the center outwards and gradually decreases along the depth direction; the distribution of earth pressure becomes more uniform with increase of the thickness of the hard shell.