CN110258642A - A kind of combined assembled underground structure of cut and cover method and its construction method - Google Patents

Abstract

The invention belongs to the field of underground engineering construction, and relates to an open-cut composite assembled underground structure. Two first side wall prefabricated parts are arranged on the bottom floor, and the two ends of the first floor are respectively supported on the two first side walls. On the prefabricated part; the first side wall prefabricated part is connected with the second side wall prefabricated part through a tongue and groove; the two ends of the second layer board are respectively supported on the two second side wall prefabricated parts. The present invention also provides a construction method of the open-cut composite assembly type underground structure. The open-cut method is adopted for construction. The bottom plate is constructed first, the first side wall prefabricated part is hoisted, and the first side wall cast-in-place layer is poured; then the first side wall is completed. The construction of the laminate; then hoist the second side wall prefabricated part, the bottom of the second side wall prefabricated part is positioned and connected with the top of the first side wall prefabricated part through the groove, and the second side wall cast-in-place layer is poured; finally the second side wall prefabricated part is completed. Laminate construction. The invention preferably realizes the assembled underground structure, has a wide application range, and can improve the overall mechanical performance of the assembled underground structure.

Description

A kind of open-cut composite assembly underground structure and its construction method

technical field

The invention belongs to the technical field of underground engineering construction, and in particular relates to an open-cut composite assembled underground structure and a construction method thereof.

Background technique

At present, the open excavation method is used to construct the underground structure with internal support foundation pit using the traditional cast-in-place reinforced concrete structure construction technology, the design process is complicated, and the workload is large; the on-site construction process requires a lot of labor of various types, and the construction environment is poor. , The construction process is complicated, the construction speed is slow, and it is greatly affected by various weather and climate, so the construction quality is difficult to guarantee. At the same time, a lot of abandoned construction waste will be generated during the construction process, which not only wastes resources but also pollutes the environment. The construction control of cast-in-place concrete structures is uneven. After the completion of the construction, there are often various quality defects in the appearance or interior of the concrete structure due to various reasons. It is difficult to repair later and the quality is difficult to guarantee.

With the progress of science and technology and the development of equipment manufacturing industry, more and more jobs are replaced by machines, labor-intensive by high technology, and manual control by automatic control equipment. Various components (beams, slabs, columns, walls) required in the field of construction engineering will gradually be mass-produced in factories, and then transported to the site for assembly.

With the development of prefabricated technology, various prefabricated designs and construction technical schemes have emerged for underground structures, some of which are only suitable for open excavation foundation pits with less groundwater and grading or anchor cables (rods). In areas where internal support is used for foundation pits and the groundwater is abundant; some only partially adopt prefabricated structures, the degree of assembly is not high, and the assembly efficiency is low; some prefabricated components are large in size and require extremely high hoisting and assembly equipment.

Contents of the invention

In order to overcome the deficiencies of the above-mentioned prior art, the object of the present invention is to provide an open-cut composite assembled underground structure and its construction method, which can effectively solve the problems of waterproofing and structural integrity of the underground assembled structure.

In order to achieve the above object, the technical solution of the present invention is an open-cut composite assembled underground structure, which includes a bottom slab, a first slab, a second slab, a first side wall prefabricated part, a second side wall prefabricated part and There are two enclosure structures, and the ground floor, the first floor and the second floor are arranged in sequence from bottom to top between the two enclosures; the bottom floor is provided with two first side wall prefabricated parts, so The two ends of the first layer board are respectively supported on two first side wall prefabricated parts; each of the first side wall prefabricated parts is provided with a second side wall prefabricated part, and the first side wall prefabricated parts pass through The groove is connected with the corresponding second side wall prefabrication; the two ends of the second layer board are respectively supported on the two second side wall prefabrication.

Further, a first side wall cast-in-place layer is provided between the first side wall prefabricated part and the corresponding enclosure structure, and a first side wall cast-in-place layer is provided between the second side wall prefabricated part and the corresponding enclosure structure. There is a second side wall cast in place.

Further, the bottom slab includes a bottom stringer prefabricated part and two bottom slab prefabricated parts for respectively supporting two first side wall prefabricated parts; the bottom stringer prefabricated part and the bottom slab prefabricated part On the concrete support plate, the bottom longitudinal beam prefabricated part is arranged between two bottom slab prefabricated parts, and a bottom slab cast-in-place connection section is poured between the bottom longitudinal beam prefabricated part and the bottom slab prefabricated part.

Furthermore, a first groove is provided on the side of the prefabricated bottom plate away from the enclosure structure, and a second concave is provided on the side of the prefabricated bottom stringer opposite to the first groove. groove, and the cast-in-place connection section of the bottom plate is located between the first groove and the second groove.

Further, the bottom longitudinal beam prefabricated part is provided with a first central column, and a first central column cast-in-place connection section is cast between the first central column and the bottom longitudinal beam prefabricated part; The first central longitudinal beam, the middle part of the first layer board is supported on the first central longitudinal beam.

Further, the first layer slab includes two first layer slab prefabricated parts, one end of each first layer slab prefabricated part is supported on the first middle longitudinal beam, and the other end is supported on the first side wall prefabricated part , the cast-in-situ layer of the first layer slab is poured on the two first layer slab prefabricated parts.

Further, the first floor board is provided with a second central column, the second central column is provided with a second middle longitudinal beam, and the middle part of the second floor board is supported on the second middle longitudinal beam .

Further, the second layer board includes two second layer board prefabricated parts, one end of each second layer board prefabricated part is supported on the second middle longitudinal beam, and the other end is supported on the second side wall prefabricated part , the cast-in-situ layer of the second layer slab is poured on the two second layer slab prefabricated parts.

The present invention also provides a construction method of an open-cut composite assembled underground structure, comprising the following steps:

1) After the construction of the two enclosure structures is completed, the crown beam will be constructed using the open cut method, and three internal supports will be erected between the two enclosure structures while excavating, and excavated to the bottom of the foundation pit;

2) Construct a concrete cushion at the bottom of the foundation pit first, then construct a waterproof layer on the concrete cushion, then construct a concrete replacement support plate on the waterproof layer, and remove the bottom inner support;

3) Hoisting the reinforcement skeleton of the first side wall, the bottom of the reinforcement skeleton of the first side wall is overlapped with the steel bars reserved on the concrete support plate, and the top is positioned and connected with the enclosure structure;

4) Complete the construction of the bottom slab;

5) Hoist the prefabricated part of the first side wall, the bottom of the prefabricated part of the first side wall is positioned and connected with the bottom plate, and the prefabricated part of the first side wall and the enclosure structure are used as the side formwork, and the prefabricated part of the first side wall and the enclosure structure Concrete is poured in between to form the cast-in-situ layer of the first side wall with the steel skeleton of the first side wall hoisted previously;

6) Complete the construction of the first center column and the first center longitudinal beam;

7) Complete the construction of the first floor, and then remove the inner support in the middle;

8) Hoist the second side wall reinforcement skeleton, the bottom of the second side wall reinforcement skeleton is overlapped with the reserved steel bars on the first side wall cast-in-place layer, and the top is positioned and connected with the enclosure structure; hoist the second side wall prefabricated parts , the bottom of the second side wall prefabricated part is positioned and connected with the top of the first side wall prefabricated part through a groove, and the second side wall prefabricated part and the enclosure structure are used as side templates, and the second side wall prefabricated part and the enclosure structure Concrete is poured in between to form the cast-in-situ layer of the second side wall with the previously hoisted steel skeleton of the second side wall;

9) Complete the construction of the second center column and the second center longitudinal beam;

10) Complete the construction of the second layer, and then remove the top inner support.

Further, the specific construction steps of the bottom slab in step 4) are as follows: hoist the bottom stringer prefabricated part and the bottom slab prefabricated part on the concrete support slab, and the steel bars reserved at both ends of the The steel bars reserved on the prefabricated slab are bound and lapped, and concrete is poured between the prefabricated bottom longitudinal beam and the prefabricated bottom slab to form the cast-in-place connection section of the bottom slab.

Further, the specific construction steps of the first layer slab in step 7) are as follows: hoisting the first layer prefabricated part, one end of the first layer prefabricated part is supported on the first middle longitudinal beam, and the other end is supported on the first side On the prefabricated part of the wall; pouring concrete on the prefabricated part of the first slab to form the cast-in-situ layer of the first slab.

Further, the specific construction steps of the second layer slab in step 10) are as follows: hoisting the second layer slab prefabricated part, one end of the second layer slab prefabricated part is supported on the second middle longitudinal beam, and the other end is supported on the second side On the prefabricated part of the wall; pouring concrete on the prefabricated part of the second slab to form the cast-in-situ layer of the second slab.

Compared with the prior art, the present invention has the following beneficial effects:

(1) The open excavation method composite assembled underground structure and its construction method provided by the present invention have a wide range of applications,

And the first side wall prefabricated part and the second side wall prefabricated part are connected by groove and groove, so as to improve the integrity of the prefabricated structure;

(2) The present invention forms a superimposed structure through the prefabricated parts and the cast-in-place layer, which can save some temporary facilities such as on-site formwork and erection of scaffolding, save the construction period, and can effectively improve the waterproof performance and overall force of the assembled underground structure performance;

(3) The present invention adopts a reasonable component block scheme, which can reduce the size and weight of a single prefabricated component, so that the size and weight of the prefabricated component can meet the requirements for on-site hoisting and assembly of a supported foundation pit, and at the same time facilitate the transportation of the prefabricated component , and can better realize the promotion and application of industrialization;

(4) The joints between the side wall prefabricated parts and the laminate prefabricated parts, the joints between the laminate prefabricated parts and the joints between the laminate prefabricated parts and the central longitudinal beams of the present invention all adopt cast-in-place "wet joints". The water resistance and integrity of the type underground structure are good;

(5) The present invention has the advantages of standardization of prefabricated parts size, reduction of design workload, improvement of production efficiency, improvement of construction quality, better realization of industrialization, saving labor, saving formwork and scaffolding, etc., shortening construction period, saving energy, and improving the work of practitioners environment and other advantages.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. Those skilled in the art can also obtain other drawings based on these drawings without creative work.

Fig. 1 is the open-cut schematic diagram of the composite fabricated underground structure provided by the embodiment of the present invention;

Fig. 2 is a schematic diagram of open excavation of a composite fabricated underground structure provided by an embodiment of the present invention;

Fig. 3 is a schematic diagram of open excavation of a composite fabricated underground structure provided by an embodiment of the present invention;

Fig. 4 is a schematic diagram of open excavation of a composite fabricated underground structure provided by an embodiment of the present invention;

Fig. 5 is a schematic diagram of open excavation of a composite fabricated underground structure provided by an embodiment of the present invention;

Fig. 6 is a schematic diagram of open excavation of a composite fabricated underground structure provided by an embodiment of the present invention;

Fig. 7 is a schematic diagram of open excavation of the composite assembled underground structure provided by the embodiment of the present invention;

Fig. 8 is a schematic diagram of open excavation of a composite fabricated underground structure provided by an embodiment of the present invention;

Fig. 9 is a schematic diagram of open excavation of a composite fabricated underground structure provided by an embodiment of the present invention;

Fig. 10 is a schematic diagram of open excavation of a composite fabricated underground structure provided by an embodiment of the present invention;

Fig. 11 is a schematic diagram of open excavation of a composite fabricated underground structure provided by an embodiment of the present invention;

Fig. 12 is a structural schematic diagram of a composite fabricated underground structure provided by an embodiment of the present invention;

In the figure: 1. Enclosure structure, 2. Crown beam, 3. Internal support, 4. Concrete cushion, 5. Concrete replacement slab, 6. Steel skeleton of the first side wall, 7. Prefabricated part of the bottom slab, 71, First groove, 8. Bottom longitudinal beam prefabricated part, 81. Second groove, 9. Bottom slab cast-in-place connection section, 10. First side wall prefabricated part, 11. Corbel, 12. First side wall in-situ Casting layer, 13, the first central column, 14, the first central column cast-in-place connection section, 15, the first middle longitudinal beam, 16, the first layer prefabricated part, 17, the first layer cast-in-place layer, 18, Second side wall reinforced skeleton, 19. Second side wall prefabricated part, 20. Second side wall laminated layer, 21. Second central column, 22. Second middle longitudinal beam, 23. Second floor prefabricated part, 24. The cast-in-place layer of the second layer slab, 25. Backfilling soil.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

In describing the present invention, it is to be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", The orientations or positional relationships indicated by "top", "bottom", "inner", "outer", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying References to devices or elements must have a particular orientation, be constructed, and operate in a particular orientation and therefore should not be construed as limiting the invention.

The terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of these features; in the description of the present invention, unless otherwise specified, the meaning of "plurality" is two or more.

Embodiment one

As shown in Figures 1 to 12, an embodiment of the present invention provides an open-cut composite assembled underground structure, which includes a base plate, a first layer plate, a second layer plate, a first side wall prefabricated part 10, a second side wall Wall prefabricated parts 19 and two enclosure structures 1, between the two enclosure structures 1 are provided with a bottom plate, a first layer plate and a second layer plate in sequence from bottom to top; the bottom plate is provided with two second A side wall prefabricated part 10, the two ends of the first layer board are respectively supported on two first side wall prefabricated parts 10; each of the first side wall prefabricated parts 10 is provided with a second side wall prefabricated part 19. The first side wall prefabricated part 10 is connected to the corresponding second side wall prefabricated part 19 through grooves; the two ends of the second layer board are respectively supported on the two second side wall prefabricated parts. The open-cut composite assembled underground structure and its construction method provided by the present invention have a wide range of applications, and the first side wall prefabricated part 10 and the second side wall prefabricated part 19 are connected by grooves to improve the integrity of the assembled structure.

Further, a first side wall cast-in-place layer 12 is provided between the first side wall prefabricated part 10 and the corresponding enclosure structure 1, and the second side wall prefabricated part 19 is connected to the corresponding enclosure structure 1. A second cast-in-place layer of side walls is provided between the structures 1 . In this embodiment, a side wall reinforcement skeleton is hoisted between the side wall prefabricated part and the enclosure structure 1, and the side wall reinforcement skeleton is spliced and positioned with the steel bars reserved on the corresponding side wall prefabricated part, and then through the side wall prefabricated part and the Concrete is poured between the enclosure structures 1 to form the cast-in-place layer of the side wall, and the cast-in-place layer of the side wall and the prefabricated part of the side wall form a superimposed structure to improve the waterproof performance and overall mechanical performance of the assembled underground structure. In this embodiment, a waterproof layer can be constructed first at the position corresponding to the side wall on the enclosure structure 1, and then the steel skeleton of the side wall is hoisted and concrete is poured to improve the waterproof performance of the side wall.

Further, as shown in FIGS. 8-12 , corbels 11 are provided on the first side wall prefabricated part 10 , and the two ends of the first layer board are respectively supported by two first side wall prefabricated parts 10 on the corbel 11 of the first side wall prefabricated part 10, and the top of the first side wall prefabricated part 10 is connected to the corresponding second side wall prefabricated part 19 through groove-and-groove positioning above the first layer. In this embodiment, by arranging the connection node between the first side wall prefabricated part 10 and the second side wall prefabricated part 19 above the first layer board, the integrity between two adjacent layers can be further improved.

As an embodiment, as shown in Fig. 4-Fig. 12, the bottom slab includes a bottom stringer prefabricated part 8 and two prefabricated bottom slab parts 7 for respectively supporting two first side wall prefabricated parts 10; Both the bottom longitudinal beam prefabricated part 8 and the bottom slab prefabricated part 7 are arranged on the concrete support plate 5, the bottom longitudinal beam prefabricated part 8 is arranged between two bottom slab prefabricated parts 7, and the bottom longitudinal beam Between the prefabricated part 8 and the prefabricated part 7 of the bottom slab, there is a cast-in-place connection section 9 for the bottom slab. The bottom plate of this embodiment is assembled and connected by multi-section prefabricated parts, which reduces the size and weight of a single prefabricated part, and facilitates the transportation, hoisting and assembly of prefabricated parts; A superimposed structure is formed on the parts and the concrete replacement brace 5, which improves the integrity and waterproofness of the structure. The bottom of the first side wall prefabricated part 10 and the top of the bottom plate prefabricated part 7 in this embodiment can be positioned and connected through a groove-and-groove structure.

Furthermore, a concrete cushion 4 is provided below the concrete brace 5, and a waterproof layer is constructed between the concrete cushion 4 and the concrete brace 5 to improve the waterproof performance of the bottom plate.

Furthermore, a first groove 71 is provided on the side of the prefabricated bottom plate 7 facing away from the enclosure structure 1 , and a side of the prefabricated bottom stringer 8 opposite to the first groove 71 A second groove 81 is provided, and the cast-in-place connection section 9 of the bottom plate is located between the first groove 71 and the second groove 81 . In this embodiment, the first groove 71 and the second groove 81 are arranged opposite to each other, so that the cast-in-place connection section 9 of the bottom slab is wide in the middle and narrow at the upper and lower ends, which further improves the integrity and waterproof performance of the assembled underground structure. In addition, the steel bars reserved on the bottom slab prefabricated part 7 protrude from the first groove 71, and the steel bars reserved on the bottom longitudinal beam prefabricated part 8 protrude from the second groove 81, and the steel bars of the two prefabricated parts are on the ground floor. Parts of the cast-in-place connection section 9 of the slab overlap to improve the connection strength of the cast-in-place connection section 9 of the bottom slab. The connection between other two prefabricated parts of this embodiment can also adopt this arrangement of grooves and reinforcing bars, such as It is used for the connection between the first ply prefabricated part 16 and the first ply prefabricated part 16 and the like.

As another embodiment, the bottom slab of this embodiment can also be a cast-in-situ concrete structure. After the concrete cushion 4 and the waterproof layer are constructed, the concrete is formed by binding the steel frame on the construction site and then pouring concrete on the waterproof layer. The concrete cast-in-place bottom slab, and steel bars are reserved at both ends of the concrete cast-in-place bottom slab so as to be positioned and connected to the bottom of the first side wall prefabricated part 10. At this time, the concrete cast-in-place bottom slab and the first side wall prefabricated part 10 They are connected by cast-in-place, and can be poured together with the first side wall cast-in-place layer 12.

Further, the bottom longitudinal beam prefabricated part 8 is provided with a first central column 13, and a first central column cast-in-place connection section 14 is cast between the first central column 13 and the bottom longitudinal beam prefabricated part 8; The first middle longitudinal beam 15 is arranged on the top, and the middle part of the first layer board is supported on the first middle longitudinal beam 15, and the first middle board is supported by the first middle column 13 and the first middle longitudinal beam 15. support in the middle. The first central column 13 and the first central column 13 of this embodiment can be cast-in-place or prefabricated. When prefabricated, the age of concrete waiting for the cast-in-place layer 12 of the first side wall can be utilized. When the assembly and fixation of the prefabricated parts are completed, the two prefabricated parts can be connected into a whole by pouring concrete to form a cast-in-place connecting section between the prefabricated parts.

As an embodiment, the first layer board includes two first layer board prefabricated parts 16, one end of each first layer board prefabricated part 16 is supported on the first middle longitudinal beam 15, and the other end is supported on the first middle longitudinal beam 15. On the side wall prefabricated part 10, the first layer slab cast-in-place layer 17 is poured on the two first layer slab prefabricated parts 16. As shown in FIG. 12 , pouring There is concrete, so that the first floor slab prefabricated part 16, the first side wall prefabricated part 10 and the first middle longitudinal beam 15 are integrated to enhance the integrity of the prefabricated underground structure. As another embodiment, the first layer includes two first layer prefabricated parts 16, one end of each first layer prefabricated part 16 is supported on the first middle longitudinal beam 15, and the other end is supported on the first On the side wall prefabricated part 10 ; between the two first ply prefabricated parts 16 and between the first ply prefabricated part 16 and the corresponding first side wall prefabricated part 10 , a first ply cast-in-place connection section is poured. In addition, in this embodiment, the first floor slab can also be in the form of full cast-in-place, by building a base form between the first side wall prefabricated part 10 and the first middle longitudinal beam 15, and then pouring after binding the steel skeleton on the construction site The concrete forms the cast-in-place first slab.

Further, the first layer is provided with a second central column 21, and the second central column 21 is provided with a second middle longitudinal beam 22, and the middle part of the second layer is supported by the second middle On the stringer 22. The middle part of the second laminate is supported by the second center column 21 and the second center longitudinal beam 22; the second center column 21 and the second center column 21 of this embodiment can be cast-in-place or prefabricated. When the form of prefabricated parts is adopted, the assembly and fixing of the prefabricated parts can be completed while waiting for the age of the concrete of the cast-in-place layer of the second side wall. The prefabricated parts are connected into a whole.

As an embodiment, the second layer board includes two second layer board prefabricated parts 23, one end of each second layer board prefabricated part 23 is supported on the second middle longitudinal beam 22, and the other end is supported on the second middle longitudinal beam 22. On the two side wall prefabricated parts 19, the second layer slab cast-in-place layer 24 is poured on the two second layer slab prefabricated parts 23. As shown in Figure 12, on the two second layer slab prefabricated parts 23, between the two second layer slab prefabricated parts 23 and between the second layer slab prefabricated parts 23 and the corresponding second side wall cast-in-place layer. There is concrete, so that the second floor slab prefabricated part 23, the second side wall prefabricated part 19, the second side wall cast-in-place layer and the second middle longitudinal beam 22 are integrated to enhance the integrity of the prefabricated underground structure. As another embodiment, the second layer board includes two second layer board prefabricated parts 23, one end of each second layer board prefabricated part 23 is supported on the second middle longitudinal beam 22, and the other end is supported on the second middle longitudinal beam 22. On the side wall prefabricated part 19 ; between the two second layer slab prefabricated parts 23 and between the second layer slab prefabricated part 23 and the corresponding second side wall cast-in-place layer, a second layer slab cast-in-place connection section is poured. In addition, the second floor slab in this embodiment can also be cast in place, by building a base form between the second side wall prefabricated part 19 and the second middle longitudinal beam 22, and then pouring after binding the steel skeleton on the construction site Concrete forms the cast-in-place second slab.

Embodiment two

The embodiment of the present invention provides a construction method of an open-cut composite assembled underground structure. The construction method of an underground two-story single-column double-span structure with three inner supports 3 is used as an example. The construction method includes the following steps:

1) After the construction of the two enclosure structures 1 is completed, the crown beam 2 is constructed, and the open cut method is used for construction. Three internal supports 3 are erected between the two enclosure structures 1 while excavating, and excavated to the bottom of the foundation pit, such as As shown in Figure 1;

2) Concrete cushion 4 is first constructed at the bottom of the foundation pit, and then a waterproof layer is constructed on the concrete cushion 4 to improve the waterproof performance of the fabricated underground structure. After the steel skeleton is hoisted on the waterproof layer and assembled, concrete is poured to form concrete Replace the brace 5, after the strength of the concrete brace 5 meets the design requirements, remove the bottom inner support 3, as shown in Figure 2;

3) Construction enclosure structure 1 leveling layer construction waterproof layer, hoisting the first side wall steel skeleton 6, the bottom of the first side wall steel skeleton 6 is lapped with the reserved steel bars on the concrete replacement slab 5, and the top is connected to the enclosure Structure 1 is positioned and connected to prevent collapse, as shown in Figure 3;

4) Complete the construction of the bottom slab;

5) Hoist the first side wall prefabricated part 10, the bottom of the first side wall prefabricated part 10 is positioned and connected with the ground floor prefabricated part 7, each first side wall prefabricated part 10 needs to be stretched, the first side wall After the prefabricated part 10 is installed, fix the first side wall prefabricated part 10 with diagonal braces to prevent it from toppling over; after the construction of the first side wall prefabricated parts 10 on both sides is completed, after 2-3 stages of construction, use the first side wall prefabricated Part 10 is used as the inner formwork of the side wall, and the enclosure structure 1 is used as the outer formwork. The gap between the concrete pouring enclosure structure 1 and the first side wall prefabricated part 10 forms the first side wall with the previously hoisted steel skeleton 6 of the first side wall. The wall cast-in-place layer 12, the first side wall cast-in-place layer 12 and the first side wall prefabricated part 10 form a laminated wall, as shown in Figures 5-6;

6) Complete the construction of the first center column 13 and the first center longitudinal beam 15;

7) Complete the construction of the first floor, and then remove the inner support 3 in the middle;

8) Construction enclosure structure 1 leveling layer construction waterproof layer, lifting the second side wall reinforcement skeleton 18, the bottom of the second side wall reinforcement skeleton 18 is lapped with the reserved reinforcement on the first side wall cast-in-place layer 12, and the top Position and connect with the enclosure structure 1 to prevent collapse; hoist the second side wall prefabricated part 19, the bottom of the second side wall prefabricated part 19 is positioned and connected with the top of the first side wall prefabricated part 10 through a groove, and the second side wall The prefabricated part 19 is stretched, and then the second side wall prefabricated part 19 is fixed by diagonal braces to prevent it from toppling over; after the construction of the second side wall prefabricated part 19 on both sides is completed, after 2-3 stages of construction, the second side wall prefabricated part 19 is used to The wall prefabricated part 19 is used as the inner formwork of the side wall, and the enclosure structure 1 is used as the outer formwork. The gap between the concrete pouring enclosure structure 1 and the second side wall prefabricated part 19 forms the second side wall reinforcement skeleton 18 previously hoisted. The cast-in-place layer of the two side walls, the cast-in-place layer of the second side wall and the prefabricated part 19 of the second side wall form a laminated wall, as shown in Figures 8-9;

9) Complete the construction of the second center column 21 and the second center longitudinal beam 22;

10) Complete the construction of the second floor, and then remove the top inner support 3; complete the pipeline relocation, roof backfilling and other work.

The open-cut construction method of the assembled flat-roofed underground structure with columns provided by the present invention better realizes the assembled underground structure and has a wide range of applications. The superimposed structure formed by the prefabricated parts and the cast-in-place layer can eliminate part of the on-site formwork , Erection of temporary facilities such as scaffolding, saving the construction period, and can effectively improve the waterproof performance and overall mechanical performance of the fabricated underground structure; adopting a reasonable component block scheme can reduce the size and weight of a single prefabricated part, which is convenient for transportation, Hoisting and assembly.

Further, as shown in Figure 4, the specific construction steps of the bottom slab in step 4) are as follows: hoist the bottom longitudinal beam prefabricated part 8 and the bottom slab prefabricated part 7 on the concrete replacement slab 5, and adjust the prefabricated components through mechanical equipment To the corresponding position, after the tensioning and fixing are completed, the steel bars reserved at both ends of the longitudinal beam prefabricated part are bound and lapped with the reserved steel bars on the bottom slab prefabricated part 7 on both sides, and the bottom longitudinal beam prefabricated part 8 and the bottom slab Concrete is poured between the prefabricated parts 7 to form the cast-in-place connecting section 9 of the bottom slab, and the construction of the bottom slab is completed. Furthermore, when the prefabricated bottom plate prefabricated part 7 and the bottom stringer prefabricated part 8 are prefabricated, the first groove 71 is processed on one side of the bottom plate prefabricated part 7, and the second concave groove 71 is processed on both sides of the bottom stringer prefabricated part 8. Slots 81; when assembled, the two second grooves 81 of the bottom longitudinal beam preform 8 are respectively opposite to the first grooves 71 on the bottom plate preforms 7 on both sides, and the first groove 71 and the second groove Concrete is poured between 81 to form the cast-in-place connecting section 9 of the bottom slab. In this embodiment, the first groove 71 and the second groove 81 are arranged opposite to each other, so that the middle of the cast-in-place connection section 9 of the bottom plate is wide, and the upper and lower ends are narrow, which further improves the integrity and waterproof performance of the fabricated underground structure; in addition, the bottom layer The reserved steel bars on the slab prefabricated part 7 protrude from the first groove 71, and the reserved steel bars on the bottom longitudinal beam prefabricated part 8 protrude from the second groove 81. 9 partially overlaps to improve the connection strength of the cast-in-place connection section 9 of the bottom slab. The connection between the other two prefabricated parts of this embodiment can also adopt this arrangement of grooves and steel bars, such as for the first layer Between the slab preform 16 and the first layer slab preform 16 and so on. In step 4) of this embodiment, the steel bars reserved on the concrete support plate 5 extend between the bottom longitudinal beam prefabricated part 8 and the bottom slab prefabricated part 7 and connect with the bottom longitudinal beam prefabricated part 8 and the bottom slab prefabricated part 7 The reserved steel bars are bound and lapped so that the prefabricated part 8 of the bottom longitudinal beam, the prefabricated part 7 of the bottom slab and the concrete support plate 5 form a composite structure.

Further, as shown in FIG. 9 , corbels 11 are provided on the first side wall prefabricated part 10 , and the two ends of the first laminate are respectively supported on the corbels of the two first side wall prefabricated parts 10 11, and the top of the first side wall prefabricated part 10 is connected to the corresponding second side wall prefabricated part 19 through groove and groove positioning above the first layer. In this embodiment, by arranging the connection node between the first side wall prefabricated part 10 and the second side wall prefabricated part 19 above the first layer board, the integrity between two adjacent layers can be further improved.

As an implementation, as shown in Figure 7, the specific construction steps of the first layer in step 7) are as follows: hoisting the first layer prefabricated part 16, one end of the first layer prefabricated part 16 is supported in the first On the longitudinal beam 15, the other end is supported on the first side wall prefabricated part 10; after each first layer prefabricated part 16 is stretched, the first layer prefabricated part 16 is used as the bottom mold, and the assembled steel mesh is completed Concrete is poured on the first floor slab prefabricated part 16 to form the first floor slab cast-in-place layer 17, and at the same time, the joint connection and joint pouring of beams and slabs, walls and slabs are completed, and the first floor slab cast-in-place layer 17 is connected with the first floor The prefabricated slab 16 forms a composite structural slab to bear all the loads on the middle slab in the later stage; after the concrete strength of the cast-in-place layer 17 of the first slab meets the design requirements, the middle inner support 3 is removed. As another implementation, the specific construction steps of the first layer in step 7) are as follows: hoisting the first layer prefabricated part 16, one end of the first layer prefabricated part 16 is supported on the first middle longitudinal beam 15, The other end is supported on the first side wall prefabricated part 10; with the first middle longitudinal beam 15 as the bottom mold, between the two first layer prefabricated parts 16 and between the first layer prefabricated part 16 and the first side wall prefabricated Concrete is poured between the pieces 10 to form the first floor slab cast-in-place connecting section, so as to improve the integrity of the fabricated underground structure. In addition, the first layer slab of this embodiment can also directly adopt the form of full cast-in-place, by building a base form between the first side wall prefabricated part 10 and the first middle longitudinal beam 15, after binding the steel skeleton at the construction site Pour concrete to form the first cast-in-place deck. After the cast-in-place strength of the first layer board meets the design requirements, the inner support 33 in the middle is removed.

As an implementation, as shown in Figure 11, the specific construction steps of the second layer slab in step 10) are as follows: hoisting the second layer slab prefabricated part 23, one end of the second layer slab prefabricated part 23 is supported in the second On the longitudinal beam 22, the other end is supported on the second side wall prefabricated part 19; after each second layer prefabricated part 23 is stretched, the second layer prefabricated part 23 is used as the bottom mold, and the assembled steel mesh is completed Concrete is poured on the second slab prefabricated part 23 to form the second slab cast-in-place layer 24, and the second slab cast-in-place layer 24 and the second slab prefabricated part 23 form a laminated structural slab to bear all the loads in the later stage; After the concrete strength of the cast-in-place layer 24 of the second-floor slab meets the design requirements, the top inner support 3 is removed. As another embodiment, the specific construction steps of the second layer slab in this embodiment are as follows: hoisting the second layer slab prefabricated part 23, one end of the second layer slab prefabricated part 23 is supported on the second middle longitudinal beam 22, and the other One end is supported on the second side wall prefabricated part 19; the second middle longitudinal beam 22 is used as the bottom formwork, and concrete is poured between the two second layer slab prefabricated parts 23 to form the first floor slab cast-in-place connection section, which improves the assembly style. The integrity of the underground structure. In addition, the first layer slab of this embodiment can also directly adopt the form of full cast-in-place, by building a base form between the second side wall prefabricated part 19 and the second middle longitudinal beam 22, after binding the steel skeleton at the construction site Pour concrete to form the second cast-in-place slab. After the cast-in-place strength of the second layer slab meets the design requirements, remove the top inner support 3 .

Further, as shown in FIG. 6 , in step 6), when both the first central column 13 and the first central longitudinal beam 15 are in the form of prefabricated parts, while waiting for the concrete age of the cast-in-place layer 12 of the first side wall, The first central column 13 is hoisted, and the steel bars reserved at the bottom of the first central column 13 are bound and overlapped with the steel bars reserved on the prefabricated bottom longitudinal beam 8. After the side formwork is built, the bottom of the first central column 13 and the bottom longitudinal beam are prefabricated Concrete is poured between the tops of parts 8 to form the first central column cast-in-place connection section 14; the first central longitudinal beam 15 is hoisted, and the top of the first central column 13 is connected by cast-in-place between the bottom of the first central column 13.

Further, as shown in Fig. 10, in step 9), when the second center column 21 and the second center longitudinal beam 22 are both in the form of prefabricated parts, while waiting for the concrete age of the cast-in-place layer of the second side wall, hoisting The second central pillar 21 and the second central longitudinal beam 22 complete the assembly and fixing of the prefabricated parts, and the prefabricated parts are connected into a whole by cast-in-place between the prefabricated parts.

The connection between the side wall prefabricated part and the laminate prefabricated part and the laminate in the open-cut composite prefabricated underground structure provided by the first embodiment of the present invention and the construction method of the open-cut composite prefabricated underground structure provided by the second embodiment The joints between the prefabricated parts and the longitudinal beams are all cast-in-place "wet joints", and the waterproof and integrity of the fabricated underground structure are good.

The construction method of the open-cut composite assembled underground structure provided by this embodiment and the open-cut composite assembled underground structure can also be used for other underground structures with N floors and M spans, and the topmost and bottommost floors can respectively adopt this implementation. The structural forms of the first basement and the second basement of the example, the side walls and laminates of the remaining floors can also adopt the structural forms of other laminates and side walls of this embodiment, and the structure of the widened part can be the same as that of this embodiment. I won’t go into details here; this embodiment uses a reasonable component block plan and pre-constructed plan to replace the support plate to build the underground structure, which is not limited by geological conditions and internal supports, and solves the problem of the construction of the internal support system in the open excavation pit belt. Difficult hoisting and assembly of prefabricated parts, poor waterproofing and poor integrity of prefabricated structures; with optimized size and weight of prefabricated components, it can meet the requirements of on-site hoisting and assembling of foundation pits with internal support, and can better realize industrialization Promote apps. The underground structure provided in this embodiment forms a superimposed structure by pouring cast-in-place layers on the outside of the side wall prefabricated parts to improve the waterproof performance and structural integrity of the assembled underground structure, and is suitable for urban rail transit underground stations, basements, comprehensive pipe corridors, etc. Main structural engineering.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the scope of the present invention. within the scope of protection.

Claims (12)

1. An open-cut composite assembled underground structure is characterized in that: it comprises a base plate, a first layer plate, a second layer plate, a first side wall prefabricated part, a second side wall prefabricated part and two enclosure structures , between the two enclosure structures, there are a ground floor, a first floor and a second floor in sequence from bottom to top; two first side wall prefabricated parts are arranged on the bottom floor, and the first floor The two ends of the two first side wall prefabricated parts are respectively supported on the two first side wall prefabricated parts; each of the first side wall prefabricated parts is provided with a second side wall prefabricated part, and the first side wall prefabricated part is connected with the corresponding The second side wall prefabricated parts are connected; the two ends of the second layer board are respectively supported on the two second side wall prefabricated parts. 2. The open-cut composite assembled underground structure according to claim 1, characterized in that: a first side wall cast-in-place is provided between the first side wall prefabricated part and the corresponding enclosure structure layer, and a second cast-in-place layer of the side wall is provided between the second side wall prefabricated part and the corresponding enclosure structure. 3. The open-cut composite prefabricated underground structure according to claim 1, characterized in that: the bottom slab comprises a prefabricated bottom longitudinal beam and two prefabricated parts for respectively supporting two first side walls. The prefabricated part of the bottom slab; the prefabricated part of the bottom longitudinal beam and the prefabricated part of the bottom slab are both arranged on the concrete support plate, the prefabricated part of the bottom longitudinal beam is arranged between the two prefabricated parts of the bottom slab, and the prefabricated part of the bottom longitudinal beam A cast-in-place connection section of the bottom slab is poured between the beam prefabricated part and the bottom slab prefabricated part. 4. The open excavation method composite assembled underground structure according to claim 3, characterized in that: the side of the base plate prefabricated part away from the enclosure structure is provided with a first groove, and the bottom longitudinal A second groove is provided on the side of the beam prefabricated part opposite to the first groove, and the cast-in-place connection section of the bottom plate is located between the first groove and the second groove. 5. The open-cut composite assembled underground structure according to claim 3, characterized in that: said bottom longitudinal beam prefabricated part is provided with a first central column, said first central column is connected to said bottom longitudinal beam The first central column cast-in-place connecting section is poured between the beam prefabricated parts; the first central longitudinal beam is arranged on the upper part, and the middle part of the first floor plate is supported on the first central longitudinal beam. 6. A kind of open-cut method composite assembled underground structure as claimed in claim 5, characterized in that: said first layer comprises two first layer prefabricated parts, each of said first layer prefabricated parts One end is supported on the first middle longitudinal beam, the other end is supported on the first side wall prefabricated part, and the first layer slab cast-in-place layer is poured on the two first layer slab prefabricated parts. 7. The open excavation method composite assembled underground structure according to claim 1, characterized in that: the first layer is provided with a second central column, and the second central column is provided with a second central column. For the longitudinal beam, the middle part of the second layer board is supported on the second middle longitudinal beam. 8. A kind of open-cut method composite assembled underground structure as claimed in claim 7, it is characterized in that: said second layer comprises two second layer prefabricated parts, each of said second layer prefabricated parts One end is supported on the second middle longitudinal beam, the other end is supported on the second side wall prefabricated part, and the second layer slab cast-in-place layer is poured on the two second layer slab prefabricated parts. 9. A construction method for an open-cut composite assembled underground structure, characterized in that it comprises the following steps: 1) After the construction of the two enclosure structures is completed, the crown beam will be constructed using the open cut method, and three internal supports will be erected between the two enclosure structures while excavating, and excavated to the bottom of the foundation pit; 2) Construct a concrete cushion at the bottom of the foundation pit first, then construct a waterproof layer on the concrete cushion, then construct a concrete replacement support plate on the waterproof layer, and remove the bottom inner support; 3) Hoisting the reinforcement skeleton of the first side wall, the bottom of the reinforcement skeleton of the first side wall is overlapped with the steel bars reserved on the concrete support plate, and the top is positioned and connected with the enclosure structure; 4) Complete the construction of the bottom slab; 5) Hoist the prefabricated part of the first side wall, the bottom of the prefabricated part of the first side wall is positioned and connected with the bottom plate, and the prefabricated part of the first side wall and the enclosure structure are used as the side formwork, and the prefabricated part of the first side wall and the enclosure structure Concrete is poured in between to form the cast-in-situ layer of the first side wall with the steel skeleton of the first side wall hoisted previously; 6) Complete the construction of the first center column and the first center longitudinal beam; 7) Complete the construction of the first floor, and then remove the inner support in the middle; 8) Hoist the second side wall reinforcement skeleton, the bottom of the second side wall reinforcement skeleton is overlapped with the reserved steel bars on the first side wall cast-in-place layer, and the top is positioned and connected with the enclosure structure; hoist the second side wall prefabricated parts , the bottom of the second side wall prefabricated part is positioned and connected with the top of the first side wall prefabricated part through a groove, and the second side wall prefabricated part and the enclosure structure are used as side templates, and the second side wall prefabricated part and the enclosure structure Concrete is poured in between to form the cast-in-situ layer of the second side wall with the previously hoisted steel skeleton of the second side wall; 9) Complete the construction of the second center column and the second center longitudinal beam; 10) Complete the construction of the second layer, and then remove the top inner support. 10. The construction method of an open excavation composite assembly type underground structure according to claim 9, characterized in that the specific construction steps of the bottom plate in step 4) are as follows: hoisting the bottom longitudinal beam on the concrete support plate For the prefabricated part and the prefabricated part of the bottom slab, the steel bars reserved at both ends of the prefabricated longitudinal beam are respectively bound and overlapped with the steel bars reserved on the prefabricated bottom slab on both sides, and poured between the prefabricated bottom longitudinal beam and the prefabricated bottom slab The concrete forms the cast-in-place connection sections of the ground floor slab. 11. The construction method of an open excavation composite assembly type underground structure as claimed in claim 9, characterized in that the specific construction steps of the first layer in step 7) are as follows: hoisting the first layer prefabricated parts, One end of the first slab prefabricated part is supported on the first middle longitudinal beam, and the other end is supported on the first side wall prefabricated part; concrete is poured on the first slab prefabricated part to form the first slab cast-in-situ layer. 12. The construction method of an open-cut composite prefabricated underground structure according to claim 9, wherein the specific construction steps of the second layer slab in step 10) are as follows: hoisting the prefabricated part of the second layer slab, One end of the second slab prefabricated part is supported on the second middle longitudinal beam, and the other end is supported on the second side wall prefabricated part; concrete is poured on the second slab prefabricated part to form the second slab cast-in-situ layer.