考虑水泥-水玻璃双液浆黏度时空效应的隧道预注浆研究

Study on pre-grouting of tunnel considering time and space effect of viscosity of cement-water glass slurry

水泥-水玻璃双液浆作为典型的速凝型浆液开始在隧道超前注浆施工中得到广泛应用,但目前对于双液浆渗透扩散机理的研究较少,注浆压力、浆液扩散半径以及注浆量等关键施工参数的确定多以经验为主.本文考虑水泥-水玻璃双液浆为黏度时变性的宾汉姆流体,基于双液浆的流变方程,同时考虑双液浆的黏度时效性和黏度空间效应,推导得到了表征双液浆黏度增长时间Tu与浆液扩散半径l之间关系的表达式.根据此关系式并结合平衡方程和均匀毛管组理论,推导得到了考虑双液浆黏度时空效应的柱形渗透注浆浆液扩散半径l和浆液压力P的理论计算公式,并分析了公式中相关参数的确定方法与公式的适用范围.

As a typical quick setting grout,the cement-sodium silicate mixed grout has been widely used in the advance grouting construction of the tunnel.But at present,there are few studies on the mechanism of the permeation and diffusion of the mixed grout,and the determination of the key construction parameters such as the grouting pressure,the grout diffusion radius and the grout amount is mostly based on experience.In this paper,in consideration of cement-sodium silicate mixed grout as Bingham fluid with time-dependent behavior of viscosity,the rheological equation based on mixed grout,and also the viscosity time-dependency and viscosity space effect of mixed grout,the expression representing the relationship between the viscosity growth time Tu and the grout diffusion radius l is derived.According to this relation expression and by means of the equilibrium equation and the theory of uniform capillary group,the theoretical formula for calculating the diffusion radius l1 and grout pressure P of column penetration grouting considering the viscosity space-time effect of mixed grout are derived,and the determination method of relevant parameters in the formula and the application scope of the formula are also analyzed.