Research On Optimal Ratio And Indoor Grouting Test Of Cement-fly Ash-clay Grout

Geotechnical engineering techniques increasingly applied in various constructions withthe rapid development of infrastructure construction and urbanization. The reinforcementmeasures of underground rock mass, as for its anisotropy and complex geological structure,are increasingly diversified. At present, grouting is one of the common methods. Comparedwith other methods, grouting has features of simple construction equipment, small scale andfloor space, short construction period. The choice of grouting materials which have anessential impact on the entire grouting process is the key of grouting technique. Therefore,only by grasping the engineering properties of grouting materials can finally grouting get therequired effect in the grouting engineering.On the basis of early literature review and indoor tests, this paper mainly focused on thebasic engineering performance of cement-fly ash-clay. And on this basis, the relationshipamong the grouting parameters was obtained by conducting grouting home-made model testsand regression analysis. At last, the functional relationship was testified in theengineering.Main research contents are as follows:1. The research status at home and abroad of grouting material have been studied andanalyzed based on a lot of literature review and field investigations. And some characteristicsof the ideal grouting material have been summed up, which could be as the basis of researchto choose grouting material. Through the classification of different flow pattern which on thepremise of Darcy seepage law theory, the spherical and cylindrical diffusion rules of groutingdiffusion law were mainly studied.2. To achieve the goal of making each material full played in good qualities, theperformance of the material element of cement-fly ash-clay grouting and their reactionmechanism of consolidation has been analyzed.3. Based on analyzing the influence of materials for mixed grouting performance, suchas cement, fly ash, clay, activity sources etc, the influence relationship among serous drainagerate, viscosity, stone rate and the strength of the different age with different ratio, has beenmainly studied through the orthogonal experiment. And finally the optimal proportion of thegrouting was concluded.4. A simple, practical and convenient grouting experimental instrument has been developed. Based on homogeneous experimental design, the simulated grouting experimentwas carried out in sand layer with optimal proportion. Through the regression analysis,quantitative relations between grouting pressure F, grouting timeT, water cement ratio Wand grouting permeating distance R, strength of reinforced body P were analyzed.5. This paper, taking Jia Zi Tou tunnel of Ren Chi expressway in Gui Zhou asengineering background, completed the tunnel collapse using osmotic grouting on the basis offield test in consideration of related parameters of indoor experiments. Monitoring resultsshow that the displacement changes were within the scope of the permit. The purpose of thereinforcement has been achieved.