Drill bit grouting stopping and drill stem sublevel retreating type grouting method

Abstract

The invention discloses a drill bit grouting stopping and drill stem sublevel retreating type grouting method. The drill bit grouting stopping and drill stem sublevel retreating type grouting method comprises the following steps of starting a drilling machine to drill a hole in a designed position; after the hole is drilled to a depth of a double pipe drill stem, detaching a high pressure water and air supply system; taking another double pipe drill stem and a hydraulic capsule liquid transport tube to be connected with the double pipe drill stem and a hydraulic capsule liquid transport tube in the hole; continuing to drill the hole to the depth of the double pipe drill stem; continuously prolonging the double pipe drill stem and the hydraulic capsule liquid transport tube till the hole isdrilled to a designed depth; injecting liquid into a grouting stopping hydraulic capsule through each hydraulic capsule liquid transport tube in sequence so that the grouting stopping hydraulic capsule expands in the radial direction of a drilled hole; enabling the grouting stopping hydraulic capsule to be closely attached to the side wall of the drilled hole; forming a sealed area in the drilledhole in front of the grouting stopping hydraulic capsule; and grouting the sealed area through each double pipe drill stem and a drill bit in sequence. By using the drill bit grouting stopping and drill stem sublevel retreating type grouting method, a grouting liquid can be prevented from being solidified to lock the drill stem and the drill bit; a convenient and fast drill stem retreating type grouting process is realized; the requirements on drilling machine equipment are low; and the loss of the drilling machine equipment is small.

Description

【Technical field】 [0001] The invention belongs to the technical field of civil engineering tunnel construction, and in particular relates to a segmented retreating grouting method for drill bits and drill rods. 【Background technique】 [0002] In the construction of tunnels and underground projects, weak water-rich strata are often encountered, which are prone to water and mud inrush and large deformation at the excavation surface, which endangers the safety of tunnel construction. At present, the grouting method is often used to improve the properties of the surrounding rock, that is, the cementitious material is injected into the surrounding rock under a certain pressure and consolidated, filling the pores and compacting the soil, and achieving a good effect of reinforcement and water blocking. [0003] At present, there are two main horizontal grouting methods: namely segmental forward grouting and drill pipe segmental retreat grouting. Drill pipe retreating type grouting...

AI Technical Summary

Problems solved by technology

This method has high grouting efficiency and short grouting construction period. However, since the grout fills the gap between the drill pipe and the drill hole, it tightly hugs the drill pipe and blocks the drill bit after consolidation (drill bit diameter > drill pipe diameter). Drill pipe retreat requires a high-power and high-torque drilling rig power head, which is repeatedly rotated and hammered to shatter the solidified slurry and then pulled out. It requires high equipment and wears heavily, and the core parts such as the spline shaft in the power head must be maintained and replaced. The cost is relatively expensive, and there is a risk of retreat and escape failure in the process of deep hole grouting that is greater than 20m

Images