Multi-zone freezing type lifting drill-cutting method for soft and hard strata

Abstract

The invention belongs to the technical field of underground engineering rock and soil drilling and cutting, and underground engineering disaster prevention and mitigation, and particularly relates toa multi-zone freezing type lifting drill-cutting method for soft and hard strata. A multi-zone independent-lifting type drill-cutting tool is adopted, so that drill-cutting tool discs of different areas are mutually combined to achieve independent up-and-down moving, and in-hole cutting tool selecting and in-hole quick cutting tool replacing in any stratum can be achieved. The construction progress is accelerated, and the construction cost is saved. A freezing type freeze-drill-cutting method is adopted meanwhile, a freezing controller is adopted to control a freezing salt water agent to discharge freezing salt water, and the freezing salt water is injected into a to-be-constructed stratum through freezing pipes with vertical extending of the cutting tool discs, so that quick freezing drill-cutting for complex strata in a multi-zone block mode is achieved. Quality accidents such as collapse due to water abundance in uneven-soft-and-hard in-hole strata can be avoided. The construction quality is reliable, and the cost is low. The method has the characteristics that the water-rich strata are fully frozen, the frozen areas are quickly selected, frozen area drilling and cutting are integrated, the drill-cutting force is uniform, the cost is low, hole-forming accuracy is high, and the drill-cutting speed is high.

Description

technical field [0001] The invention belongs to the technical field of underground engineering rock and soil drilling and cutting and underground engineering disaster prevention and mitigation, in particular to a multi-zone freezing type lifting drilling and cutting method for soft and hard strata. Background technique [0002] Soft and hard stratum is a kind of heterogeneous stratum, which is the main danger source of geological disasters in the process of underground engineering construction. Accidents such as the collapse of the shield tunnel opening and the change of the tool surface, and the rupture of the subsea water-rich tunnel. This is because the construction of crossing the soft and hard stratum is different from a single soft stratum and hard stratum. The drilling and cutting speed of the formation and the reaction force of the uneven hard and soft formation to the drilling and cutting tool are not equal, so that the drillability of the soft and hard formation is...

AI Technical Summary

Problems solved by technology

[0002] The soft and hard stratum is a kind of heterogeneous stratum, which is the main source of danger for geological disasters in the process of underground engineering construction, especially the uneven soft and hard stratum rich in water, which can easily cause surface settlement, pile position deviation, and surface building collapse , the collapse of the tool change surface of the shield tunnel, and the rupture of the subsea water-rich tunnel. The drilling and cutting speed of the formation and the reaction force of the uneven soft and hard formation to the drilling and cutting tool are not equal, resulting in the drillability of the soft and hard formation being different from that of a single soft and hard formation, resulting in the drilling and cutting of the drilling construction surface. Force ratios are more difficult to control in single soft and hard formations

[0003] Existing drilling devices for soft and hard formation mainly include super large diameter shield cutter head, shield scraper, shield machine tool, PDC bit, geophysical scour bit, etc. The cutting device is mainly rock-socketed pile air-pressure-controlled cutting, but shield drilling devices such as super-large-diameter shield cutterhead, shield scraper, shield machine tool, etc. are bulky and expensive. Drilling devices such as engineering survey drilling devices have small hole diameters, blade distribution angles and cutter distribution settings are unreasonable, and when rock-socketed piles are controlled by air pressure to cut soft and hard strata, the cutting force of the cutting surface cannot change in real time with the stratum. needs improvement

Therefore, the existing drilling and cutting devices for the construction of soft and hard formations are mainly single drilling devices and cutting devices, lacking a composite drilling and cutting device with both drilling and cutting functions.

[0004] Chinese patent CN106907158A is a super-large-diameter shield cutterhead system for soft and hard uneven formations, including large cutterheads, medium-sized cutterheads, small cutterheads, spokes, panels, hobs, cutters, leading knives, center knives, Stirring rods, reducers, hydraulic motors, power transmission devices, shields, and screw excavation devices, but the layout of the cutterhead system is a multi-layer cutterhead space staggered distribution, which is expensive. When the cutterhead encounters soft and hard strata for drilling construction However, due to the limitation of the overall structure of the front cutter head of the shield machine, the shield machine can only be driven into soft and hard areas by controlling various cutter heads, and it is difficult to effectively control the drilling and cutting forces of the corresponding cutting surfaces in different layers of soft and hard layers. , at the same time it cannot cut hard formations in soft and hard formations

[0005] Chinese patent CN206495679U is a kind of shield scraper used in soft and hard uneven formations. There is a hard alloy on the back of the body, and a wear-resistant alloy layer on the cutting edge of the cutter body. However, the shield scraper is mainly to enhance its impact resistance in bad formations, and the cost is high, so it cannot guarantee the protection of soft and hard formations. The accuracy of the main structure during construction cannot be used for drilling and cutting rock and soil in soft and hard formations

[0006] Chinese patent CN204552753U is a shield machine tool suitable for soft and hard uneven strata, including multiple tool combinations installed on the cutter head. The tool combination includes hobs and cutting knives. The shaft of the hob is equipped with sensors. The rear part is fixedly installed on the cutter head, and the rear part of the cutter is installed on the cutter head through a base with a hydraulic expansion device. The base can move back and forth along the shield machine axis, but the shield machine tool is limited The front cutterhead of the shield machine is an integral structure, which can only be drilled into the rock and soil by controlling the hob and cutter, and cannot accurately adjust the penetration of the shield cutterhead during construction in various strata such as soft stratum, hard stratum, and soft-hard stratum. The drilling force of the surface is high, and the cost is high, and the hard formation in the soft and hard formation cannot be cut

[0007] Chinese patent CN203891774U is a five-blade PDC drill bit suitable for soft and hard formations, including a drill body and five blades protruding from the crown of the drill body, and several grooves for discharging debris are formed between the blades , the drill bit drills holes by adjusting the distribution angle of the blade and the distribution of the main cutting teeth on the blade. It cannot guarantee the stress uniformity of the main structure in soft and hard formations, and cannot be used for drilling and cutting in soft and hard formations in rock and soil.

This device is mainly aimed at the stress situation when cutting soft and hard rocks. It maintains constant pressure on the soft rocks that are drilled and applies air pressure to the hard rocks that are not fully cut. The problem of real-time adjustment of the cutting force on the cutting surface of different formations such as strata, and the rapid discharge of chips when cutting soft and hard formations cannot be solved, especially hard formations cannot be cut, and the force uniformity of the cutting device cannot be maintained

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