Method for arc bending excavation of lower bending section of vertical shaft

Abstract

The invention discloses a method for arc bending excavation of the lower bending section of a vertical shaft. The arc bending triangular body of the lower bending section of the vertical shaft is evacuated up and down in advance, and a guide groove is evacuated at the rest part after completion of advanced excavation, so that a space with visual lines unobstructed is formed between the rear wall of the vertical shaft and the tail end of the lower bending section; it is ensured that a total station obtains good sighting conditions; through setting of measuring points of the total station and known control points in a lower flat section, the control points are led to the tail end of an anchor rod in the vertical shaft; not only is it ensured that the control points in the vertical shaft arenot covered during spray anchoring, but also the control points are led into the vertical shaft; thereby facilitating hole-by-hole smooth blasting hole setting-out of the arc bending part subsequently; finally the survey and setting-out accuracy is ensured, and the excavation construction quality is improved; and the molding accuracy of the arc bending part is ensured.

Description

technical field [0001] The invention relates to the field of shaft excavation, in particular to a method for excavating curved arcs in the lower bend of a shaft. Background technique [0002] At present, the level of precise body shape control in the excavation measurement of the downward bend of the vertical shaft is low at home and abroad, and there are many overbreaks, especially the research on the precise shape control of the bend section is insufficient. During the measurement and stakeout of curved arc excavation in the lower bend of the vertical shaft, the known backsight point is usually used to carry out the specific stakeout measurement work from the known backsight point to the straight stakeout position. There are problems such as missing control points in the vertical shaft and obstructed line of sight, which eventually leads to construction progress. Lags, poor construction quality and waste of resources. [0003] The method of surveying and setting out for c...

AI Technical Summary

Problems solved by technology

[0004] The existing excavation methods have the following deficiencies: 1) The curved triangle in the downward bend of the shaft will block the line of sight from the bottom of the downward bend in the shaft and the inner wall of the shaft, and the total station cannot obtain good visibility conditions, which affects the measurement of the total station; 2) Due to the impact of the on-site excavation of the shaft, the measurement control points in the shaft are difficult to preserve and will be missing, resulting in insufficient accuracy of measurement and stakeout, which affects the quality of excavation construction

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