Narrow and long open caisson of thick soft soil layer and construction method thereof

Abstract

The invention provides a narrow and long open caisson of a thick soft soil layer and a construction method thereof and relates to the technical field of open caisson construction. The open caisson isformed by splicing a plurality of segments. The method comprises the following steps of S1, setting the position of the open caisson, and arranging a cement mixing pile on a soil layer at the open caisson to reinforce the soil layer; S2, manufacturing the first segment above the soil layer; S3, draining away water in an in-well area and cutting earth till the segment descends to a position which is a preset distance from the ground; S4, manufacturing the next segment contrapuntally on the manufactured segment S5, draining away water in an in-well area and cutting earth till the next segment descends to a position which is a preset distance from the ground; S6, repeating the steps 4-5 till all segments are manufactured; and S7, carrying out grouting to the bottom of the open caisson and sealing the bottom. Phenomena such as bottom heave and sedimentation of soil layers around the open caisson due to a too large water pressure in the open caisson in the sinking process can be prevented.

Description

technical field [0001] The invention relates to the technical field of caisson construction, in particular to a narrow and long caisson in thick soft soil layers and a construction method thereof. Background technique [0002] The thick soft soil layer has the characteristics of high natural water content, low strength, easy uplift of the bottom of the pit, and return of quicksand, so it is difficult to carry out caisson construction. In Chen Guoping's "Construction Technology and Application of Caisson Subsidence in Soft Soil Foundation", a caisson construction method is proposed, which uses heavy well point dewatering as an auxiliary process to consolidate the silt while reducing the groundwater level, so as to ensure the solidification after consolidation. The soil quality can satisfy the sinking of the caisson. [0003] However, this method is difficult to ensure the stability of the large caisson sinking, and the caisson may be tilted under the action of soft soil when...

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Problems solved by technology

[0003] However, this method is difficult to ensure the stability of the large caisson sinking, and the caisson may be tilted under the action of soft soil when the caisson sinks.

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