Study On Pre-support Action Mechanism And Effect Of Horizontal Rotary Jet Grouting Piles

Horizontal rotary jet grouting piles is a pre-support construction method that by way of pressing slurry using high pressure jet in horizontal holes, this technology could form a arching pre-lining at profile in tunnel construction to protect the working face and reduce surface subsidence. The practice has prove that pre-support technology of horizontal rotary jet grouting piles is a well fast and economic pre-support technology in tunnel construction at china, and this technology would have widespread application prospects.The paper is on the basis of the large number of previous research results,including mechanism of the high pressure jet grouting,classification structure,influencing factors,basic physical and mechanical properties of the horizontalsolidification,applying theory analysis, Finite element analysis researchmethods,making a in-depth research on mechanism of the horizontal rotary jet grouting piles and technical factors.The principal contents in paper is:1,Application range of horizontal rotary jet grouting piles pre-consolidation and its advantages and disadvantages are described. Meanwhile, the design for construction method of horizontal rotary jet grouting piles was analyzed to some extent. And this text concluded some aspects of this construction method including construction equipment, the design of process parameters, process steps, pile-test methods, frequently problems and corresponding treatments. Finally, some pre-reinforced methods were compared and analyzed with each other.2,This text studied deeply on the structure and characteristics of high-pressure squirt flow, its destructive effect on soil and action mechanism of forming pile by horizontal rotary jet grouting piles.3,The loads acted on horizontal rotary jet grouting piles pre-support were discussed. The grouting-arching by horizontal rotary jet grouting was simplified into an opening cylindrical shell. A three-dimensional mechanical model of tunnel construction by horizontal rotary jet grouting piles pre-support technology was built and its elastically-analytical solution was derived.4,By way of numerical simulation software FLAC3D, this text compared the simulated result which used horizontal rotary jet grouting piles pre-support with the simulated result which not, as well as the simulation results compared with the theoretical calculation results. Based on the compare mentioned before, functionary effect and preliminary conclusion by horizontal rotary jet grouting piles pre-support technology was come out.