变态混凝土注浆扩散机制及其在软弱围岩地层加固中的可行性研究  

Study on diffusion mechanism of metamorphic concrete grouting and its feasibility in reinforcing soft surrounding rock strata

作　　者：饶力 RAO Li(Department of Civil Engineering,Yichun University,Yichun 336000,China)

机构地区：[1]宜春学院土木工程系,江西宜春336000

出　　处：《混凝土》2022年第1期172-176,184,共6页Concrete

摘　　要：为了探索变态混凝土注浆在软弱围岩地层加固应用的可行性,从其扩撒机理的研究入手,首先在文献调研的基础上借助于模型试验对变态混凝土浆液注浆扩散性能的因素进行了研究;然后以采用浅埋暗挖法施工的新建隧道为例,对变态混凝土在软弱围岩地层加固中的应用进行了数值模拟研究;最后采用开挖取样法对注浆效果进行了评价,研究成果表明:首先,实际施工中可将注浆压力、注浆量、浆液的水胶比和颗粒直径作为主控因素,并借助于模型试验得到各影响因素与注浆扩散半径之间的函数关系;其次,基于COMSOL ultiphysics有限元仿真结果表明,变态混凝土在孔隙率为0.34的软弱围岩中的有效扩散半径能达到1 700~1 900 mm;最后,变态混凝土在某新建隧道软弱围岩地层加固中的应用情况表明,变态混凝土浆液能很好地在软弱围岩中流动,填充围岩孔隙的同时,能沿着围岩裂隙渗入到土体结构深层中去,进一步起到加固软弱围岩的作用,同时还具备良好的防渗效果;可见,软弱围岩地层加固中采用变态混凝土注浆是行之有效的措施之一。In order to explore the feasibility of the application of metamorphic concrete grouting in the reinforcement of soft surrounding rock strata,it starts with the study of its spreading mechanism.Firstly,on the basis of literature investigation and model test,the factors affecting the grouting diffusivity of metamorphic concrete are studied.Then,taking a new tunnel constructed by shallow buried excavation method as an example,the application of metamorphic concrete in the reinforcement of soft surrounding rock strata is numerically simulated.Finally,the grouting effect is evaluated by excavation sampling method.The research results show that firstly,in actual construction,grouting pressure,grouting volume,water-binder ratio of grout and particle diameter can be taken as the main controlling factors,and the functional relationship between the influencing factors and grouting diffusion radius is obtained by means of model test.Secondly,finite element simulation results based on COMSOL ultiphysics show that the effective diffusion radius of metamorphic concrete in soft surrounding rock with porosity of 0.34 can reach 1700~1900 mm.Finally,the application of metamorphic concrete in the reinforcement of soft surrounding rock strata of a newly built tunnel shows that metamorphic concrete grout can flow well in soft surrounding rock,fill in the surrounding rock pore,and infiltrate into the deep soil structure along the surrounding rock fissures,further strengthening the weak surrounding rock,and also has good seepage control effect.It can be seen that the use of abnormal concrete grouting in the reinforcement of soft surrounding rock strata is one of the effective measures.

关 键 词：变态混凝土 软弱围岩 地层加固 扩散机理 模型试验 

分 类 号：TU528.01[建筑科学—建筑技术科学]