Study Of Grouting Technology’s Mechanism And Application In Subgrade Reinforcement

With the rapid development of our country’s road traffic business,the task of maintenance and reinforcement reconstruction for all levels of road become increasingly heavy,grouting technology has been widely used in road subgrade strengthening.However,for the reason that grouting engineering is concealed engineering,the slurry flow involves many factors and the soil structure is complicated,the existing grouting theory lagging behind the engineering application,especially that the mechanism and application of grouting technology in the roadbed reinforcement lack a systematic research conclusion,which cause it difficult to guide the construction effectively.As a consequence,on the basis of a large number of theoretical analysis and literature research,the mechanism and application of grouting technology applied in subgrade reinforcement are studied in this paper aiming at the existing problems and the insufficiency of existing research.In this paper,cement slurry and sand mass are chosen as the object of study,self-designed experimental equipment was used to carry out the indoor test which combined with numerical analysis tools,the mode and rule of diffusion as well as the reinforcement effect of cement slurry in the sand mass are analyzed systematically,through which a series rules and conclusions are obtained.(1)Based on existing theory of groutability,the permeability test of cement slurry in the sand mass is carried out,by which the law that how particle size of sand,water cement ratio of cement slurry and grouting pressure influence the groutability of sand mass is studied.The applicable scope of the cement slurry applied in the subgrade reinforcement is put forward through the data analysis.(2)The diffusion rule of cement slurry and the law that how water cement ratio of cement slurry and grouting pressure influence the diffusion range are studied through the indoor test,the assumed mathematical model of the grouting concretion body is built based on the test conclusion and the concept of main reinforcement area and secondary reinforcement area is put forward,quantitative relationship between diffusion range of cement slurry and water cement ratio of cement slurry as well as grouting pressure is established,and the rationality of the laboratory test set is verified through.finite element software.(3)Based on the result of cement-treatment-sand test and a number of assumption,the reinforcement effect of grouting in sandy soil subgrade is studied,the scope of the optimal amount of cement adding in subgrade soil is obtained,what’s more,the early increasing low of intensity of subgrade after grouting is obtained,which confirmed that the grouting technology can meet the needs of early opening to traffic in road maintenance;the influence law of grouting reinforcement depth for subgrade reinforcement effect is obtained by the BISAR software,and the economy and reasonable reinforcement depth range is obtained.(4)Based on the grouting project of the section from K61+870 to K61+980 of S331 road,the rebound deflection of the pavement surface before and after grouting is measured,which verifies the effectiveness of the grouting treatment technology for subgrade reinforcement.