Guiding device for supporting construction of foundation pit in narrow zone and construction method

Abstract

The invention provides a guiding device for supporting construction of a foundation pit in a narrow zone and a construction method. The structure is as the follows that an original box culvert is cutinto two sections of a front section and a rear section by an intercepting well; an inner circle and an outer circle of high-pressure jet grouting piles are constructed at the periphery of an intercepting well foundation pit; H-shaped steels are interpolated in modes of closely inserting and inserting one by one with one interval; the outer circle of high-pressure jet grouting pile is arc-shaped,and the positions, the right above the front section and the rear section of the original box culvert, of two ends of the outer circle of high-pressure jet grouting pile are connected with the inner circle of high-pressure jet grouting pile through full reinforcement of the high-pressure jet grouting pile; a reinforced concrete inner support is arranged between the inner circle and the outer circle of high-pressure jet grouting piles, and a guide groove foundation pit is excavated between piles; and the front and rear sections of the original box culvert are respectively provided with holes inthe side wall and the holes communicate with the guide grooves; and the front section and the rear section of the original box culvert respectively use the positions corresponding to the right lowerparts of the H-shaped steels inserted into the inner circle of high-pressure jet grouting pile as a plugging part, a temporary plugging wall is formed between the underwater concrete and the intercepting well, and bidirectional steel bars are configured in the wall. The device meets the requirement of foundation pit supporting and simultaneously has construction diversion capability.

Description

technical field [0001] The invention relates to a deep foundation pit support structure and a construction method, in particular to a diversion device and a construction method for foundation pit support construction in a narrow area. Background technique [0002] At present, the deep foundation pit support of urban rainwater and sewage tank culvert renovation projects has the following defects in the support structure and construction diversion method adopted for the side wall of the foundation pit and the surrounding environment: 1. The single cement-soil enclosure wall lacks bearing capacity , large stress deformation; 2. The soil extrusion process of reinforced concrete sheet piles is more serious, the cost is high, the construction is inflexible, and the space is limited; 3. Bored piles are not suitable for small foundation pits and their quality is relatively low. Difficult to control, labor-intensive and time-consuming, and the hole forming speed is slow; 4. The tradi...

AI Technical Summary

Problems solved by technology

[0002] At present, the deep foundation pit support of urban rainwater and sewage tank culvert renovation projects has the following defects in the support structure and construction diversion method adopted for the side wall of the foundation pit and the surrounding environment: 1. The single cement-soil enclosure wall lacks bearing capacity , large stress deformation; 2. The soil extrusion process of reinforced concrete sheet piles is more serious, the cost is high, the construction is inflexible, and the space is limited; 3. Bored piles are not suitable for small foundation pits and their quality is relatively low. Difficult to control, labor-intensive and time-consuming, and the speed of hole formation is slow; 4. Traditional foundation pit support only has support bearing capacity and no construction diversion capacity

[0004] However, the above-mentioned deep foundation pit support construction technology is often limited by the space due to the inflexibility of the construction, the concrete quality is difficult to control, it is labor-intensive and time-consuming, and the hole forming speed is slow, resulting in a delay in the construction period.

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