Improved structure of shield machine applied to water-rich sandy cobble stratum and construction method

Abstract

The invention discloses an improved structure of a shield machine applied to a water-rich sandy cobble stratum. The improved structure comprises a cutter head, cutter seats, a stirring bar, a centralhob, a soil bin, a foam system, an external circulating water system and a slag discharging system. The improved structure is characterized in that repair welding of grating wear-resistant welding isperformed on the circumference and a panel of the cutter head, the cutter seats and the stirring bar respectively; a grating plate for blocking cobbles with grain size larger than that conveyed by a screw conveyor from entering the soil bin is added at a slag inlet of the cutter head; a water pipe is added to the external circulating water system, one end of the water pipe communicates with a water outlet of an external circulating water radiator, and the other end of the water pipe communicates with the soil bin after penetrating through a partition plate; and the water pipe is in serial connection with a pneumatic control valve, a flowmeter and a one-way valve sequentially from the water outlet of the external circulating water radiator to the partition plate of the soil bin. Continuoustunneling time is increased, the continuous tunneling distance is increased, and continuous rapid tunneling construction can be performed during continuous tunneling. The invention also discloses a construction method of shield tunneling in the water-rich sandy cobble stratum.

Description

technical field [0001] The invention relates to a shield tunneling technology, in particular to an improved structure and a construction method of a shield machine applied to a water-rich sand and pebble stratum. Background technique [0002] With the rapid development of urban construction in our country, the urbanization process is accelerating, the urban population is highly concentrated, and the ground traffic is congested. The subway will become an important means of transportation for people to travel. [0003] The construction method of the shield is that the "shield" (referring to the supporting segment) of the tunnel is constructed (laid) by the roadheader while excavating, which is different from the open construction method. As a tunnel construction method with a high degree of mechanization, shield tunneling has become an important means of urban underground space development, and its wide application is self-evident. A shield machine is a tunnel boring machine ...

AI Technical Summary

Problems solved by technology

Due to the short cutting track of the center hob, the hob cannot rotate, and the phenomenon of eccentric grinding of the blade or even the cracking of the cutter ring occurs, which will lead to an increase in the thrust of the excavation and the rotational torque of the cutter head, slow down the excavation speed, and excessive discharge of slag, resulting in a change in ground subsidence. Large or even collapse, in addition, it is difficult to cut pebbles, the actual excavation surface is far beyond the theoretical excavation surface, prone to over-discharge

Traditional shield machines are prone to serious problems such as poor slag discharge, cutter head jamming, screw machine jamming, and mud cake formation in mudstone strata during shield tunneling construction in water-rich sand and pebble strata.

The aforementioned problems lead to intermittent excavation of shield tunneling and slow excavation speed

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