Construction method of deep foundation pit open caisson self-sinking support system

Abstract

The invention discloses a construction method of a deep foundation pit open caisson self-sinking support system. The construction method comprises the following steps that after the pay-off, blade feet made by the cast-in-place are measured, spray heads are pre-buried in the blade feet, a first section ring beam is subjected to cast-in-situ manufacturing, a first section prefabricated open caissonwell body is installed, steel pipes are pre-buried in the open caisson well body, after the open caisson well body is connected with the blade feet, the soil body is cut by water injection and mud isdischarged, and the first section open caisson well body sinks to the designed elevation, after the ring beam is subjected to cast-in-place construction, the next section open caisson well body is installed, the water injection and sinking are carried out by adopting the same method as the first section open caisson well body, all the open caisson well bodies are installed in sequence, so that the open caisson well bodies of all the sections sink in place, and bottom sealing and mud drainage are carried out. According to the construction method of the deep foundation pit open caisson self-sinking support system, the open caissons are assembled in a prefabricated manner, the soil body is converted into the mud to be discharged outwards to enable the open caissons to sink automatically, thesoil pressure and the bottom water pressure at the peripheries are balanced by utilizing the mud in the open caisson, the excavation difficulty is reduced, and the stability in the sinking and excavation process is ensured.

Description

technical field

[0001] The invention relates to the technical field of underground space support structures, in particular to a construction method for a deep foundation pit caisson self-sinking support system. Background technique

[0002] With the shortage of construction land resources, the development of urban underground space has been paid more and more attention. The urban underground space is gradually developing towards ultra-deep and super-large, such as urban underground garages, deep well tunnels, subway stations, and underground complexes, etc. emerge in endlessly. The excavation and support technology of deep foundation pits will also face unprecedented challenges. Precipitation is difficult, and groundwater usually induces dangers such as quicksand, piping, and sudden surges, which have a significant impact on the surrounding building environment; excavation has a wide range of impacts. The extrusion of lateral earth pressure makes the bearing capacity of the...

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