Double pipe multifunctional grouting device and its construction method

Abstract

The invention relates to a double-tube type multifunctional grouting device and its construction method, comprising a grouting pipe and a spraying pipe, the grouting pipe includes an inner pipe and an outer pipe; the outer pipe is an elastic pipe, and the outer pipe is provided with a The grout mouth, the outer tube wraps the inner tube; the inner tube includes an inner tube wall attached to the inner side of the outer tube, and two grouting pipes are formed inside the inner tube wall, and the side wall of the grouting pipe is provided with an inner grout outlet; The grouting pipe is matched with the grouting pipe and inserted into the grouting pipe; it also includes a connecting rod, which is a double-sided dovetail-shaped rod-shaped structure. The gap is matched; this scheme can be applied to various mixing methods, and can be injected into two injection areas at the same time and multiple times. The root grouting pipe can directly expand the grouting depth range, providing a strong guarantee for the implementation of ultra-deep hole grouting.

Description

technical field [0001] The invention belongs to the technical field of grouting construction, and relates to a double-tube multifunctional grouting device and a construction method thereof. Background technique [0002] The widely used and recognized grouting method in geotechnical engineering is to use pressure to inject liquid grout through the borehole and use various types of grouting pipes placed below the hole into the soil void or rock formation fissure, through filling, infiltration, The original loose soil particles, gravel or crack channels are blocked and cemented into a whole by means of compaction and splitting, so that the physical and mechanical properties and hydraulic properties of the soil layer are improved. Grouting reinforcement is a systematic technical construction method, and different types of grouting construction methods are required to improve soil quality according to the specific conditions of the site in order to obtain the best engineering eff...

AI Technical Summary

Problems solved by technology

[0005] The existing double-pipe double-plunger construction method is to use the upper and lower sealing plugging devices to limit the injected material into the foundation soil layer within a certain range at the specified depth position, and can also perform repeated grouting operations for many times, so it has the advantages of The advantage of good grouting effect, on the other hand, because there is only one channel for injecting material, it is limited to the nozzle mixing method, and it is difficult to extend to the pipe bottom mixing method; Compared with the rod method, it has complex operation procedures and disadvantages in terms of cost and construction period.

In addition, grout injection can only guarantee one injection material channel, and each step (each depth position) must be injected once and twice in sequence, so there are problems such as low construction efficiency

[0006] On the other hand, both the above-mentioned single-phase and dual-phase double-pipe drill pipe injection methods require step-by-step lifting or step-down construction while changing the injection area to the depth direction in turn.

Therefore, grouting operation must be carried out in each step, especially if the foundation soil layer of construction is deep, there are problems such as long time for grouting operation; During the grouting process, the drill pipe needs to be disassembled as the position changes, so there will be continuous switching of the grouting drill pipe. When cleaning with water is required, the grouting construction needs to be suspended, and the overall construction time will be extended. , so continuous construction cannot be guaranteed, and there are problems such as low efficiency of injection work

[0007] In addition, the casing material injected by the existing sleeve valve grouting pipe in the borehole is not a fast-setting material and is easily diluted by groundwater. Therefore, there is a gap between the sleeve valve grouting pipe and the hole wall, which makes the The pressure makes the grout go up, it is difficult to reach the soil layer at the predetermined reinforcement position, which seriously affects the grouting effect, and it is easy to squeeze and deform the sleeve valve pipe embedded in the hole, making it impossible to carry out subsequent grouting operations, and it is not easy to use for a long time , short service life

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