Calculation Method of Pitching Bending Moment of Shield Cutterhead Under Geological Conditions of Upper and Lower Layers

Abstract

The invention discloses a method for computing the pitching bending moment of a shield knife flywheel under upper-lower lamination geological conditions. The method disclosed by the invention comprises the following three steps: (1) judging the geological lamination conditions of an excavated surface, wherein the excavated surface is divided into an upper geological layer and a lower geological layer; the working condition 1 indicates that the geological cladding depth of the upper layer is less than the radius of the knife flywheel; the working condition 2 indicates that the geological cladding depth of the upper layer is larger than the radius of the knife flywheel; (2) if the working condition 1 is determined, computing the pitching bending moment M1 of the knife flywheel under the working condition 1; and (3) if the working condition 2 is determined, computing the pitching bending moment M2 of the knife flywheel under the working condition 2, wherein different computational formulas are used under the different working conditions. In the method disclosed by the invention, pitching bending moment control targets in engineering lines are determined in advance according to the geological lamination conditions and can be adjusted at any time along with the change of the geological conditions and the operating states in the excavating course, thereby improving the hysteresis ofa traditional control method and providing scientific and effective technical guidance for maintaining the effective and safe linear forwarding of a shield.

Description

technical field [0001] The invention belongs to the shield machine construction technology, in particular to a calculation method for predicting the pitching moment of a shield machine cutter head under certain geological conditions. Background technique [0002] In recent years, with the gradual development of underground transportation construction in many cities, the shield tunneling method, as an engineering method for tunnel excavation, has been more and more widely used in subway construction due to its advantages of less disturbance to the surrounding environment. In most tunnel projects, the excavation surface soil is divided into different geological layers from top to bottom due to natural deposition and other reasons, and the pressure gradient of the soil will gradually increase with the increase of the buried depth due to the self-weight of the soil. big. Therefore, when the shield machine excavates in the upper and lower layered geology, due to the uneven distr...

AI Technical Summary

Problems solved by technology

At present, the application of the bending moment mainly depends on the experience of the operator of the shield machine. Once the shield head is found to be offset during the excavation process, the bending moment should be adjusted immediately. Of course, there will be a certain lag

Especially in some construction sections where the geological conditions change drastically, due to the lack of pre-adjustment basis, unnecessary losses are often caused

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