Construction method suitable for construction adit entrance area with relatively poor geological conditions

Abstract

The invention provides a construction method suitable for a construction adit entrance area with relatively poor geological conditions, and relates to the technical field of various construction adit entrance constructions. The construction method comprises the steps that a construction adit entrance section area is excavated, and side slopes on the two sides and a front adit face side slope adopt different slope ratios; the excavated side slopes on the two sides are timely subjected to reinforcing mesh hanging and anchor-gunited supporting, and drainage holes are formed in the side slopes; after excavation of the front adit face side slope is completed, slope attaching concrete construction is conducted in time, so that the side slope stability of a front adit face is ensured; construction of an advanced grouting large pipe shed is performed; and construction of an open cut tunnel section of the entrance area is performed, wherein arrangement of a road surface from the open cut tunnel section to a downhill section of an outer side slope is performed, so that it is guaranteed that external rainwater cannot be collected into a construction adit. According to the method, the construction requirement is met, good safety guarantee is provided for subsequent excavation and supporting of an adit body section of the construction adit, the safety construction condition can be improved, and the engineering investment is effectively saved.

Description

technical field [0001] The invention relates to the construction field of water conservancy and hydropower projects, in particular to a construction method suitable for the entrance area of ​​a construction branch tunnel with poor geological conditions. Background technique [0002] In water conservancy and hydropower projects, in order to transport or divert water, closed water channels are often dug through mountains, called water transport tunnels. In most cases, the water tunnel is long and closed. In order to shorten the construction period of the tunnel and increase the ventilation conditions in the tunnel, a suitable location will be selected to arrange the construction branch tunnel to connect to the water tunnel. [0003] Under normal circumstances, the location of the entrance of the water conveyance tunnel will be selected in an area with a relatively gentle slope and good geological conditions, which is conducive to excavation into the tunnel. If the geological ...

AI Technical Summary

Problems solved by technology

If the geological conditions of the overall slope are poor, if you choose to excavate to the bedrock layer for tunnel construction, the overall investment will be large, and the excavation volume of the tunnel entrance slope will be large, and the construction safety will be poor, which is not conducive to the project as a whole. construction

Images