Foundation pit containment structure with prestress ribs on vertical soil-retaining structure and construction method

Abstract

The invention discloses a foundation pit containment structure with prestress ribs on a vertical soil-retaining structure and a construction method. The structure comprises the vertical soil-retaining structure, a plurality of horizontal supports, a reinforced concrete ring beam and a plurality of surrounding purlins, wherein the vertical soil-retaining structure is arranged on the edge of the inner side of a foundation pit and consists of a plurality of drilling concrete piles or concrete continuous walls which are arranged at intervals; the reinforced concrete ring beam is arranged on the top of the vertical soil-retaining structure; the surrounding purlins are arranged on the inner circumferential surface of the vertical soil-retaining structure at intervals from top to bottom; and the horizontal supports are connected to the reinforced concrete ring beam and a plurality of surrounding purlins along the transverse intervals of the foundation pit. The foundation pit containment structure with the prestress ribs on the vertical soil-retaining structure and the construction method have the advantages that phenomena of the inwards horizontal displacement of the vertical soil-retaining structure and settlement of the ground outside the foundation pit can be reduced, the bending rigidity of the vertical soil-retaining structure is improved, and the prestress ribs can be recycled, so that the construction cost can be reduced.

Description

technical field [0001] The invention belongs to the technical field of foundation pit excavation and protection engineering for underground engineering in construction engineering and subway engineering, and in particular relates to a foundation pit protection structure with prestressed tendons on a vertical retaining structure and a construction method. Background technique [0002] At present, the excavation and protection works of underground engineering foundation pits in construction projects and subway projects generally adopt horizontal support + vertical retaining structure, and the vertical retaining structure usually adopts reinforced concrete piles or continuous walls. Hot-rolled ribbed steel bars have disadvantages such as low tensile strength, large amount of steel bars, and cannot be recycled and reused; in addition, under the action of earth pressure, the concrete on the tensile side of the vertical retaining structure will produce cracks, and work with cracks ...

AI Technical Summary

Problems solved by technology

[0004] Chinese patent application No. 01253503.6 discloses a prestressed underground diaphragm wall, which is made by prefabrication. The disadvantage is that the diaphragm wall will not actively bend to the outside of the foundation pit before excavation, so it is not suitable for larger Deep foundation pit, and prestressed tendons cannot be recovered

[0005] Chinese patent application No. 200420029700.5 discloses a concrete cast-in-place pile using steel rods for prestressed concrete. The difference between this concrete cast-in-place pile and ordinary concrete piles is that steel rods for prestressed concrete are used, and no prestress is applied. Its disadvantages The anti-cracking and tensile properties of the pile have not been improved, and the prestressed tendons cannot be recycled

[0006] Disclosed in the Chinese patent application No. 03113753.9 is a kind of deep foundation pit support prestressed pile, wall construction method, the prestressed pile that this method refers to, the bottom of the wall is provided with anchorage end (strand wire direct anchor, H anchor and P anchor ), the disadvantage is that the prestressed piles and walls will not actively bend to the outside of the foundation pit before the excavation of the foundation pit, and the prestressed tendons cannot be recovered

[0007] Chinese patent application No. 01126590.6 discloses a prestressed underground diaphragm wall. The diaphragm wall is made by prefabrication. The prestressed tendons at the top of the wall are anchored to the wall. The disadvantage is that the diaphragm wall is before excavation of the foundation pit. Does not actively bend to the outside of the excavation, so it is not suitable for deep excavations

[0008] Chinese patent application No. 200410081456.1 discloses a post-tensioned pile body prestressed anti-slide pile and its construction method. The top and bottom of the prestressed pile referred to in this document are provided with anchorage end anchorages. The disadvantage is that the prestressed tendons cannot Recycle

Images