桩底后压浆浆液扩散问题研究

采用钻探取样方法，对渗透性地层中桩底后注浆浆液扩散及固结状态进行检验。实物样品表明，在相对均匀的地层中，浆液扩散呈现出向下、向侧、向上不同的渗透能力：向下最强，向侧次之，向上最弱。在粗细交互地层中，颗粒越粗，渗透更好，扩散更远；水泥浆的含量更高。在同一地层中，距注浆出口越近，水泥浆含量越高。取样结果还表明：在桩底，压力、温度不同于地表，特别是有丰富地下水的环境下，水泥浆的凝结固化时间延迟非常显著。

Study on Grout Diffusion of Pile-bottom Post Grouting

In permeable formation, the diffusion and consolidation states of pile-bottom post grout were inspected with the sampling method. The practicality samples showed that in relatively homogeneous strata, grout diffusion were with different downward, sideward and upward penetration ability, each was the strongest, the second place and the weakest. In the alternating strata of coarse and fine particles, more coarse was the particle, the better was the permeability, the farther was the diffusion and the higher was the cement content; and in the same strata, the nearer to the grout outlet, the higher was the cement content. The sampling also indicates that the pressure and temperature at the pile bottom are different from the surface; especially in the environment with plentiful groundwater, the time delay for cement slurry condensation curing was very obvious.