CN-121992797-A - Deep foundation pit combined steel frame pre-supporting device and construction method thereof

CN121992797ACN 121992797 ACN121992797 ACN 121992797ACN-121992797-A

Abstract

The invention provides a deep foundation pit combined steel frame pre-supporting device and a construction method thereof, wherein the device comprises a pre-supporting steel frame unit layer, a servo pre-supporting mechanism and a vertical connecting pipe; the two adjacent pre-supporting steel frame unit layers are connected through vertical connecting pipes, a plurality of pre-supporting steel frame unit layers are distributed along the vertical interval to form a pre-supporting steel frame main body, servo pre-supporting mechanisms are arranged at the two side ends of each pre-supporting steel frame unit layer, pre-supporting groove sections are formed between underground continuous walls on two sides of a foundation pit in a construction mode, the pre-supporting groove sections are distributed along the wall length direction of the underground continuous walls at intervals, a group of pre-supporting steel frame main bodies can pass through the lower portion of the lifting device in each pre-supporting groove section, and the two side ends of the group of pre-supporting steel frame main bodies are propped against the inner walls of the underground continuous walls on two sides of the foundation pit through the servo pre-supporting mechanisms. The invention relates to the technical field of civil construction engineering construction, and can solve the problems that displacement, landslide and even sudden collapse are easy to occur in the traditional construction of a foundation pit which is firstly excavated and then supported.

Inventors

MEI YINGBAO
GUO XIAOHANG
YANG KE
LI CHUANG
SONG WEIQING
FANG YINGANG
XIE XIAOLIN
LI JIAPING
Zhu Yandeng
ZHAI JIEQUN
YAN JINGYA
CAO DONG
WANG LUJIE
LI RONGSHUAI

Assignees

上海建工集团股份有限公司
同济大学建筑设计研究院(集团)有限公司
上海地铁监护管理有限公司

Dates

Publication Date: 20260508
Application Date: 20260213

Claims (10)

1. A combined steel frame pre-supporting device for a deep foundation pit is characterized by comprising pre-supporting steel frame unit layers, servo pre-supporting mechanisms (9) and vertical connecting pipes (11), wherein the two adjacent pre-supporting steel frame unit layers are connected through a plurality of vertical connecting pipes (11) to enable the two adjacent pre-supporting steel frame unit layers to be arranged in parallel, the plurality of pre-supporting steel frame unit layers are distributed along the vertical interval to form a pre-supporting steel frame main body, the servo pre-supporting mechanisms (9) are arranged at two side ends of each pre-supporting steel frame unit layer, pre-supporting groove sections (3) are formed between underground continuous walls (2) at two sides of the foundation pit (17) in a construction mode, the pre-supporting groove sections (3) are distributed along the longitudinal direction of the underground continuous walls (2), a group of pre-supporting steel frame main bodies can be placed in each pre-supporting groove section (3) through lifting equipment, and two side ends of the group of pre-supporting steel frame main bodies are supported on the inner walls of the underground continuous walls (2) at two sides of the foundation pit (17) through the servo pre-supporting mechanisms (9).
2. The deep foundation pit combined type steel frame pre-supporting device according to claim 1 is characterized in that each pre-supporting steel frame unit layer comprises a node connecting piece (8), a first standard joint (10) and a second standard joint (18), a pair of first standard joints (10) and a pair of second standard joints (18) are connected into a rectangular frame structure through four node connecting pieces (8), the node connecting pieces (8) at four corners of the rectangular frame structure are connected with one ends of servo pre-supporting mechanisms (9), when the rectangular frame structure is horizontally placed in a pre-supporting groove section (3), the other ends of the four servo pre-supporting mechanisms (9) can be propped against the inner walls of underground continuous walls (2) at two sides of a foundation pit (17), and vertical connecting pipes (11) between two adjacent pre-supporting steel frame unit layers are connected between the two node connecting pieces (8) located on the same vertical line.
3. The deep foundation pit combined steel frame pre-supporting device according to claim 2, wherein a nipple (12) is connected between the node connecting piece (8) and one end of the servo pre-supporting mechanism (9).
4. A deep foundation pit combined steel frame pre-supporting device as claimed in claim 2 or 3, characterized in that the inner walls of the four node connectors (8) of the first pre-supporting steel frame unit layer are respectively connected with a hanging ring plate (13), the upper parts of the hanging ring plates (13) extend upwards to the upper parts of the node connectors (8) and hanging ring holes (16) are formed, so that the hanging ring plates (13) can be connected with slings of a lifting device through the hanging ring holes (16).
5. The deep foundation pit combined steel frame pre-supporting device according to claim 4, wherein the transverse section and the longitudinal section of the node connecting piece (8) are of cross-shaped structures, and a plurality of inner ribbed plates (14) are connected between the inner wall of the node connecting piece (8) and the hanging ring plate (13) at intervals.
6. The deep foundation pit combined steel frame pre-supporting device according to claim 2, wherein four node connecting pieces (8) of the first pre-supporting steel frame unit layer are connected with fixed connecting rods (6), and the upper ends of the fixed connecting rods (6) are fixedly connected with guide walls (5) of the underground continuous wall (2).
7. The deep foundation pit combined steel frame pre-supporting device according to claim 1 or 2, wherein reinforcing piles (1) are constructed on the outer side of the pre-supporting groove section (3), a plurality of reinforcing piles (1) are arranged between underground continuous walls (2) on two sides of a foundation pit (17) along the length direction of the pre-supporting groove section (3), and two adjacent reinforcing piles (1) are connected in a meshed mode.
8. A method of constructing a deep foundation pit composite steel frame pre-support apparatus of claim 2, comprising the steps of: step 1, constructing an underground continuous wall (2) and reinforcing the groove wall of the underground continuous wall (2); step 2, constructing a guide wall (5) and carrying out grooving construction of the pre-supporting groove section (3); Step 3, assembling and hoisting the pre-supporting steel frame main body; Step 4, loading the servo pre-supporting mechanism (9) so that the two side ends of the pre-supporting steel frame main body can be propped against the inner walls of the underground diaphragm walls (2) at the two sides of the foundation pit (17) through the servo pre-supporting mechanism (9); Step 5, connecting a fixed connecting rod (6) between the top of the pre-supporting steel frame main body and the guide wall (5), and backfilling solidified soil of the pre-supporting groove section (3); and 6, repeating the steps 2 to 5, and sequentially completing the pre-support construction of the pre-support steel frame main body in the pre-support groove sections (3).
9. The construction method according to claim 8, wherein the step 3 comprises the sub-steps of: step 31, connecting a pair of first standard joints (10) and a pair of second standard joints (18) into a rectangular frame structure through four node connecting pieces (8) to form a pre-supporting steel frame unit layer, and splicing a plurality of pre-supporting steel frame unit layers in sequence according to the supporting height; Step 32, installing a servo pre-supporting mechanism (9) outside four node connectors (8) of each pre-supporting steel frame unit layer through a nipple (12); Step 33, connecting the connecting nodes (8) of the two adjacent pre-supporting steel frame unit layers through vertical connecting pipes (11) to form a pre-supporting steel frame main body; step 34, installing a hanging ring plate (13) on the connecting node (8) of the first pre-supporting steel frame unit layer; step 35, connecting slings of the hoisting equipment to hoisting ring holes (16) of a hoisting ring plate (13), and lowering the pre-supporting steel frame main body into the pre-supporting groove section (3) through the hoisting equipment after hardening treatment of the field; and 36, filling micro-expansion self-compaction concrete between the bottom of the lowest pre-supporting steel frame unit layer and the bottom of the pre-supporting groove section (3).
10. The construction method according to claim 8, wherein in the step 5, the solidified fluid soil is recharged through an embedded irrigation pipe, the embedded irrigation pipe and the fixed connecting rod (6) are synchronously lowered, the fixed connecting rod (6) and the connecting node (8) of the first pre-supporting steel frame unit layer are bound and fixed, and after the pre-supporting steel frame main body is lowered into place and loaded with the servo pre-supporting mechanism (9), the pre-supporting groove section (3) is refilled by pumping the solidified fluid soil through the embedded recharge pipe.

Description

Deep foundation pit combined steel frame pre-supporting device and construction method thereof Technical Field The invention relates to the technical field of civil construction engineering construction, in particular to a deep foundation pit combined steel frame pre-supporting device and a construction method thereof. Background Along with the promotion of the urban process, the deep foundation pit construction is particularly important in the field of construction engineering. The deep foundation pit excavation relates to the change of underground soil and rock stratum, and can possibly cause geological layer change, including soil settlement, groundwater level change and rock stratum movement, and the phenomenon is particularly obvious in the subway deep foundation pit excavation process, and the phenomenon not only affects underground structures and geological environment, but also can cause problems of foundation settlement, building inclination and the like of surrounding buildings. The construction logic of 'first excavation and then supporting' is adopted for the traditional foundation pit support, but the risk of displacement, landslide and even sudden collapse caused by overlong soil exposure time is easily caused for deep foundation pit engineering construction. Therefore, a deep foundation pit combined steel frame pre-supporting device and a construction method thereof are needed to be provided, and the problems that displacement, landslide and even sudden collapse are easy to occur in the traditional foundation pit construction of firstly excavating and then supporting in the prior art can be solved. Disclosure of Invention The invention aims to provide a deep foundation pit combined steel frame pre-supporting device and a construction method thereof, which can solve the problems that displacement, landslide and even sudden collapse are easy to occur in the traditional foundation pit construction of 'firstly excavating and secondly supporting' in the prior art. In order to achieve the above object, the technical scheme of the present invention is as follows: A combined steel frame pre-supporting device for a deep foundation pit comprises pre-supporting steel frame unit layers, servo pre-supporting mechanisms and vertical connecting pipes, wherein two adjacent pre-supporting steel frame unit layers are connected through a plurality of vertical connecting pipes, the two adjacent pre-supporting steel frame unit layers are arranged in parallel, the plurality of pre-supporting steel frame unit layers are arranged at intervals along the vertical direction to form a pre-supporting steel frame main body, the servo pre-supporting mechanisms are arranged at two side ends of each pre-supporting steel frame unit layer, pre-supporting groove sections are formed between underground continuous walls on two sides of the foundation pit in a construction mode, the pre-supporting groove sections are arranged at intervals along the wall length direction of the underground continuous walls, a group of pre-supporting steel frame main bodies can be placed down through lifting equipment in each pre-supporting groove section, and the two side ends of each group of pre-supporting steel frame main body are propped against the inner walls of the underground continuous walls on two sides of the foundation pit through the servo pre-supporting mechanisms. Each pre-supporting steel frame unit layer comprises node connectors, a first standard joint and a second standard joint, a pair of first standard joints and a pair of second standard joints are connected into a rectangular frame structure through four node connectors, the node connectors at four corners of the rectangular frame structure are connected with one ends of the servo pre-supporting mechanisms, when the rectangular frame structure is horizontally placed in the pre-supporting groove section, the other ends of the four servo pre-supporting mechanisms can be propped against the inner walls of underground continuous walls at two sides of a foundation pit, and vertical connecting pipes between two adjacent pre-supporting steel frame unit layers are connected between two node connectors located on the same vertical line. And a short connecting pipe is connected between the node connecting piece and one end of the servo pre-supporting mechanism. The inner walls of the four node connecting pieces of the first pre-supporting steel frame unit layer are respectively connected with a hanging ring plate, and the upper parts of the hanging ring plates extend upwards to the upper parts of the node connecting pieces and are provided with hanging ring holes, so that the hanging ring plates can be connected with slings of hanging equipment through the hanging ring holes. The transverse section and the longitudinal section of the node connecting piece are in cross-shaped structures, and a plurality of internal ribbed plates are connected between the inner wall of the node connectin