Application Of Horizontal Jet Grouting At Pre-reinforcing Construction

Horizontal jet grouting is a kind of new rock and soil reinforcement technology in recent years, which comes from vertical jet grouting, and can be used at construction work like subway, tunnel, mine passage, civil defense, foundation reinforcement, rock-soil anchoring and some other special condition. Horizontal jet grouting takes high pressure pump as power source, jets mixed fluid into soil by drill pipe and jetting nozzle. High energy fluid penetrates soil, and cuts soil when the jetting nozzle is rotating and feeding/retracting, which mixes the soil and fluid. When the fluid is solidified, a column type pile is formed which is called horizontal jet grouting pile, horizontal jet grouting piles occlude together and forms into a ring type roof which can stop flowing sands, sliding and infiltration.With basis of lots previous research, and considerations of high pressure jet grouting mechanism, influence factors and solid mechanics, with research methods like theoretical analysis, numerical simulation, field experiments and so on, here in this paper gives further study about working mechanism and influencing factors of horizontal grouting. Main contents are:With lots of field experiments, this paper introduces studies about main construction parameters, technological process, reinforcement effect and influencing factors of horizontal jet grouting, bring forward reasonable improve solutions of horizontal jet grouting drilling rig, and by establishing numerical model, analyze the effect of jet grouting pile at soil disturbance, get the anchoring effect and engineering effect of horizontal jet grouting end-enlarged drill pipe with different anchoring forms, drill pipe length and different size bearing plates.According to the theories of beam on winkler foundation and finite element, gives shallow-buried advanced support in tunnel excavation disturbed zone model, and reason out the analytic solutions of reinforce beam effect and special condition of arched tunnel pre-support and finite model according to Winkler foundation beam disturb-overlying model, the solutions are verified by factual construction measuring, gives the applicable conditions of the above solutions. After further study of tunnel support influencing factors, this paper puts forward the ideal of integral designing of tunnel support made by horizontal jet grouting.Horizontal jet grouting technology is adapted at Liuyanghe reinforced jet grouting tunnel support construction at Xiangjiang Street, Changsha, solves the problems about drilling efficiency, drilling depth and hole making, makes further optimization of reinforced jet grouting tunnel support construction technology and technical parameters.