Fourfold pipe stratum decompression type double-liquor rotary spraying construction method

Abstract

The invention discloses a construction process of four-fold tube stratum decompression type double liquid jet grouting in the construction project technology field, which comprises the following steps that firstly forming a drilling lance boom with four-fold coaxial steel tubes, arranging passages in the inner portion of a multifunctional injector, which is relative to the four-fold tube of the drilling lance boom, installing two nozzles on the upper portion and the lower portion of the lateral side of the injector, secondly positioning, thirdly drilling holes, fourthly conducting jet grouting and injecting plaster, coaxially spraying compressed air and high-pressure cement plaster by the nozzles on the upper portion of the injector, and coaxially spraying high-pressure cement plaster and low-pressure accelerator serum by nozzles on the lower portion of the injector, wherein the low-pressure serum is externally coated on the high-pressure cement plaster, which are mixed with earth at the moment of being sprayed out in order to fast solidify soft ground, and fifthly conducting jet grouting to the design height, closing the valve for transporting fluid, and shifting a driller. The construction process solves the problems that the jet grouting solidification is hard to be conducted under the station of underground water flowing and jet grouting pile with large diameter and horizontal jet grouting solidification are hard to form. The invention reduces pressure for stratum through absorbing out waster mud water in the drilling and jet grouting process, and reduces the affect to the periphery.

Description

technical field [0001] The invention relates to a construction method in the technical field of construction engineering, in particular to a construction method of a quadruple-pipe formation decompression double-liquid rotary spraying method. Background technique [0002] The high-pressure rotary grouting construction technology uses a rotating nozzle to spray high-speed fluid while cutting the soil while mixing the cement slurry with the chopped soil. After a chemical reaction, a solid reinforced soil column is formed, and the strength can reach more than several MPa. This construction method was invented by Dr. Nakanishi from NIT in Japan. It was originally a simple single-pipe method (also known as CCP method) and only sprayed cement slurry. Later, the double-pipe method and triple-pipe method were developed; the double-pipe method uses compressed air to coaxially wrap the high-pressure cement slurry to cut the soil and mix the two, so that the diameter of the reinforced ...

AI Technical Summary

Problems solved by technology

The present invention overcomes the defect of the above-mentioned rotary spraying construction by spraying two-liquid slurry (cement slurry and quick-setting agent) to make the mixed soil instantaneously solidify, so that the technology can be constructed in the soil layer with groundwater flow; by using a vacuum pump to force the mud The method of reducing the formation pressure, expanding the deep cutting radius or reducing the impact on the surrounding stratum during horizontal rotary spraying, so that the double-liquid rotary spraying can be constructed at a large depth, thereby solving the problem that it is difficult to perform rotary spraying solidification under the condition of groundwater flow problems, and the difficulty of generating large-diameter jet grouted piles and horizontal jet grouted reinforcements under large depth conditions

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