The method of preventing the opening of the lower irrigation area during joint grouting of arch dams

Abstract

The invention discloses a method for preventing a lower-layer irrigated area from expanding during arch dam joint grouting. The method comprises the following steps: I, performing opening degree monitoring on an irrigated area, adjacent seams and the lower-layer irrigated area; II, if the lower-layer irrigated area is started to be opened, pre-grouting adjacent seams in the two sides of the irrigated area and performing grouting operation on the irrigated area, wherein the grouting sequence of two adjacent seams is that one of the adjacent seams with small opening degree is preferential; III, while the opening degree of the irrigated area reaches a certain value during the grouting operation, reducing pulp inlet pressure; when the lower-layer irrigated area is not opened, gradually increasing the grouting pressure and paying attention to the opening degree of the irrigated area simultaneously; if the grouting pressure is increased to a designed value and the opening degree of the irrigated area does not exceed a pre-warning value, ending grouting by closing the grouting when the pulp inlet amount is smaller than a preset value; when the lower-layer irrigated is opened, immediately feeding in pulp from a gas vent tube, slowly increasing the grouting pressure and ending the grouting according to the needs within an opening degree limit value of the irrigated area. The method has the characteristics of high seam-jointing and grouting quality, a short construction period and low cost, and can be widely applied to the cement grouting construction field of civil engineering.

Description

technical field [0001] The invention relates to the construction technology of cement grouting in civil engineering, in particular to a method for preventing the opening of the lower irrigation area during joint grouting of arch dams. Background technique [0002] The joint grouting of an arch dam belongs to the technical field of cement grouting construction of hydraulic structures, and the technology can be widely used to reduce and prevent the opening phenomenon of the transverse joints in the lower irrigation area during the transverse joint grouting process of the concrete arch dam. [0003] Arch dam construction is restricted by structural layout, geological conditions, mass concrete temperature control requirements, and pouring equipment capabilities. It is necessary to set transverse joints on the dam body in the direction perpendicular to the dam axis. In the later stage, in order to meet the needs of water retaining, dam body stress transmission and structural stab...

AI Technical Summary

Problems solved by technology

[0013] (3) For the case where the opening of the lower irrigation area has already occurred, there is a lack of operational guidance for controlling the opening of the lower irrigation area when joint grouting is performed in the irrigation area

[0014] However, in the existing water conservancy projects, the problem of increasing the opening of the lower irrigation area is only treated with supplementary irrigation, and the problem has not been solved from the source.

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