砂土介质注浆扩散规律试验研究

Experimental Study on the Diffusion Law of Sand Medium Grouting

为研究超细水泥浆液在砂土中的扩散规律,以赵固一矿西翼进风巷围岩加固为研究背景,设计了一套砂土注浆试验装置,运用正交设计法开展了多组砂土注浆试验,分析了单位时间流量、水灰比、砂土渗透系数等因素对浆液扩散体积和注浆量的敏感性及影响,系统讨论了不同渗透系数条件下,随注浆流量和水灰比变化浆液结石体形状的变化规律。研究结果表明:浆液扩散范围的影响因素主次排序为单位时间流量、水灰比、渗透系数,影响注浆量因素的主次顺序与浆液扩散体积的影响因素一致。发现单位时间流量、水灰比和渗透系数对浆液扩散体积和注浆量的影响并非呈线性关系,而是呈多元幂函数关系,构建了对应的浆液扩散体积和注浆量求解式,并对影响浆液扩散体积和注浆量的参数进行了回归分析。在渗透系数较大的砂土中,浆液以渗透注浆为主,结石体形状呈规则的圆球状,注浆流量和水灰比增大对结石体积影响显著。随着砂土渗透系数减小,结石体形状沿薄弱面发展,即由沿四周的均匀渗透扩散向沿薄弱面发展的劈裂注浆,注浆流量增大和水灰比减小对劈裂注浆有积极作用。研究结果可为松散砂土环境下地下工程注浆设计和施工提供参考。

In order to study the diffusion law of ultra-fine cement slurry in sandy soil,a sand injection test device was designed based on the reinforcement of the surrounding rock of the west wing of Zhaogu No.1 Mine.Multiple sets of sand injection tests were constructed using orthogonal design method.The sensitivity and effect of factors such as flow rate per unit time,water cement ratio,and sand permeability coefficient to the diffusion volume and injection volume of the slurry were analyzed,and the shape variation pattern of the slurry stone bodies with changes in grouting flow rate and water cement ratio under different permeability coefficient conditions were systematically discussed.The study results indicate that the precedence order of factors affecting the diffusion range of slurry are flow rate per unit time,water cement ratio,and permeability coefficient.The precedence order of factors affecting the grouting volume is consistent with the factors affecting the diffusion volume of the slurry.It was found that the effects of unit time flow rate,water cement ratio,and permeability coefficient on the diffusion volume and grouting volume of the slurry are not non-linear,but rather a multivariate power function relationship.Corresponding equations for solving the diffusion volume and grouting volume of the slurry were constructed,and regression analysis was conducted on the parameters that affect the diffusion volume and grouting volume of the slurry.In sandy soil with high permeability coefficient,the slurry mainly relies on infiltration grouting,and the shape of the stone body is a regular spherical shape.The increase in grouting flow rate and water cement ratio has a significant impact on the volume of the stone body.As the permeability coefficient of sand decreases,the shape of the stone body develops along the weak surface,that is,from uniform infiltration and diffusion along the surrounding area to splitting grouting along the weak surface.The increase in grouting flow rate and the decrease in water cement ratio have a positive effect on splitting grouting.The study results can provide reference for the grouting design and construction of underground engineering in loose sandy soil environment.