Sedimentation post-cast strip structure in reverse construction method engineering

Abstract

The utility model relates to the technical field of structural engineering and geotechnical engineering, and discloses a settlement post-cast strip structure in reverse construction method engineering, which comprises a reverse construction area structural beam, in-beam force transmission section steel is arranged in the center of the interior of the reverse construction area structural beam, and a settlement post-cast strip range structural beam is arranged at the middle end of the interior of the reverse construction area structural beam. The settlement post-cast strip range structural beam is arranged on the outer wall of the in-beam force transmission profile steel in a sleeving mode, and widening parts are arranged on the left side and the right side of the reverse construction area structural beam correspondingly. In the utility model, according to the stress characteristics of the structure at different construction stages, a settlement post-cast strip treatment method adaptive to the stress characteristics is respectively adopted, the widened area is additionally arranged on the side surface of the structural beam by not casting the beam in the post-cast strip range during the reverse construction period of the underground structure, and the post-cast strip in the structural slab area is temporarily closed; the horizontal force transmission problem of the basement reverse construction stage structure is solved.

Description

Technical Field

[0001] This utility model relates to the fields of structural engineering and geotechnical engineering, and in particular to a settlement post-cast strip structure in reverse construction engineering. Background Technology

[0002] The reverse construction method is a design method that combines the main structure and the support structure. It uses the main structure as the horizontal internal support of the support structure. It has advantages such as high support stiffness, which can strictly control the deformation of the foundation pit, no need to replace the support, which can save engineering costs and speed up the construction progress. It has been widely used in foundation pit projects with sensitive environment and high protection requirements.

[0003] For top-down construction projects with towers on the ground, settlement strips are typically installed around the tower to address differential settlement between the tower and surrounding structures. This is especially problematic in geological environments with deep rock strata, where friction piles or end-bearing friction piles are used because the pile tips cannot penetrate the rock. During top-down construction, structural beams and slabs, in addition to serving as horizontal internal supports, often function as excavation platforms, access channels for excavation machinery, and material storage areas. A key technical challenge in top-down construction is how to meet both the horizontal load-bearing requirements of the settlement strip and the vertical load-bearing requirements of these functions. To address this technical issue, this application proposes a settlement strip structure for top-down construction projects. Utility Model Content

[0004] The purpose of this utility model is to address the shortcomings of existing technologies by proposing a settlement post-cast strip structure for reverse construction engineering. This structure solves the problem of meeting the horizontal force transmission requirements of reverse construction conditions at the settlement post-cast strip location, while also meeting the vertical force requirements as an excavation platform, soil removal channel, and material storage yard.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A settlement-post-cast strip structure in a reverse construction method includes a reverse construction area structural beam. An internal force-transmitting steel section is located at the center of the reverse construction area structural beam. A settlement-post-cast strip area structural beam is located at the middle of the internal part of the reverse construction area structural beam. The settlement-post-cast strip area structural beam is fitted onto the outer wall of the internal force-transmitting steel section. Widening sections are provided on both the left and right sides of the reverse construction area structural beam. Upper longitudinal reinforcement bars are embedded at the top and bottom of the internal part of the reverse construction area structural beam. Construction sections are provided on opposite sides of the widening sections on both sides.

[0007] Furthermore, the widening section includes two beam side widening areas respectively fixedly connected to the left and right sides of the structural beam in the reverse construction area. The bottom side of the beam side widening area is provided with a portion below the bottom of the beam side widening area plate. Multiple additional upper longitudinal reinforcement bars are embedded in the top of the beam side widening area. Multiple additional lower longitudinal reinforcement bars are embedded in the bottom of the portion below the bottom of the beam side widening area plate. Multiple additional web reinforcement bars are embedded on both the left and right sides of the portion below the bottom of the beam side widening area plate. PVC pipes are embedded in the top of the adjacent sides of the two portions below the bottom of the beam side widening areas plate.

[0008] Furthermore, the construction unit includes two reverse-operation area structural plates respectively fixedly connected to the opposite side of the widened areas on the two beams. The interior of the two reverse-operation area structural plates is permeated with a settlement post-cast strip structural plate, and the left and right ends of the settlement post-cast strip structural plate are permeated with internal force-transmitting steel.

[0009] Furthermore, an expansion sealing strip is embedded at the intersection of the structural slab in the reverse construction area and the structural slab in the settlement post-cast strip area.

[0010] Furthermore, temporary supports are installed on the bottom side of the reverse operation area structural plate.

[0011] Furthermore, the rear end of the structural slab in the reverse construction area is provided with slab reinforcement bars.

[0012] Furthermore, multiple additional stirrups for the widened area are installed at the top rear end of the widened area on the side of the beam. Beam stirrups are nested inside the additional stirrups for the widened area. Several of the additional stirrups for the widened area are located on the top side of the structural slab within the settlement and pouring strip range, and the outer wall is fitted with large stirrups for the outer perimeter of the widened area.

[0013] Furthermore, an additional large outer stirrup is installed at the top front end of the widened area on the side of the beam.

[0014] This utility model has the following beneficial effects:

[0015] 1. In this utility model, settlement post-cast strip treatment methods can be adopted according to the stress characteristics of the structure at different construction stages. By not pouring the beams within the post-cast strip area during the reverse construction of the underground structure, a widened area is added to the side of the structural beam, and the post-cast strip in the structural slab area is temporarily closed, which solves the problem of horizontal force transmission of the basement structure during the reverse construction stage, while meeting the stress requirements of the basement roof slab as an excavation platform, soil removal passage and material storage yard.

[0016] 2. In this utility model, by setting temporary supports on both sides of the post-cast strip to fall onto the base plate, the vertical load on both sides of the post-cast strip is transferred to the base plate. By using the force-transferring steel pre-embedded in the beams and slabs in the early stage, the structural differential settlement and horizontal force transmission problems of the post-cast strip position during the construction of the upper main building are solved, thereby improving the overall stability. Attached Figure Description

[0017] Figure 1 This is a structural plan view of a settlement post-cast strip structure in reverse construction engineering proposed in this utility model.

[0018] Figure 2 This is a detailed cross-sectional view of the widened section of the beam side of a post-settlement cast-in-place strip structure in a reverse construction project proposed in this utility model.

[0019] Figure 3 This is a detailed drawing of the stirrup arrangement in the widened area of ​​the beam side of a post-settlement cast strip structure in a reverse construction project, as proposed in this utility model.

[0020] Figure 4 This is a detailed cross-sectional view of the post-settlement pouring strip structure in the reverse construction method proposed in this utility model, along the direction of the post-settlement pouring strip.

[0021] Figure 5 This utility model presents a detailed drawing of the stirrup arrangement in the widened area on the side of the beam within the settlement post-cast strip structure of a reverse construction project.

[0022] Figure 6 This is a detailed cross-sectional view of a structural slab perpendicular to the direction of the settlement post-cast strip in a reverse construction method proposed in this utility model.

[0023] Legend:

[0024] 1. Structural beams in the reverse construction area; 2. Structural beams within the settlement-post-cast strip area; 3. Structural slabs in the reverse construction area; 4. Structural slabs within the settlement-post-cast strip area; 5. Widened area on the side of the beam; 6. Part of the slab below the bottom of the widened area on the side of the beam; 7. Force-transferring steel in the beam; 8. Force-transferring steel in the slab; 9. PVC pipes; 10. Upper longitudinal reinforcement of the beam; 11. Lower longitudinal reinforcement of the beam; 12. Additional upper longitudinal reinforcement in the widened area; 13. Additional lower longitudinal reinforcement in the widened area; 14. Additional web reinforcement in the widened area; 15. Beam stirrups; 16. Additional stirrups in the widened area; 17. Large stirrups around the widened area; 18. Additional large stirrups at the ends of the widened area; 19. Slab reinforcement; 20. Expansion waterproofing strips; 21. Temporary supports. Detailed Implementation

[0025] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0026] Please see the appendix Figure 1 -Appendix Figure 6 This utility model embodiment provides a settlement post-cast strip structure in reverse construction engineering, wherein, attached Figure 2 For the appendix Figure 1 A cross-sectional view of the AA logo, with attached. Figure 4 For the appendix Figure 1 A cross-sectional view of the BB logo, attached. Figure 6 For the appendix Figure 1 The cross-sectional view of the CC includes the structural beam 1 of the reverse construction area. The internal center of the structural beam 1 of the reverse construction area has an internal force-transfer steel 7. The internal middle of the structural beam 1 of the reverse construction area has a structural beam 2 of the settlement post-cast strip range. The structural beam 2 of the settlement post-cast strip range is fitted on the outer wall of the internal force-transfer steel 7. The left and right sides of the structural beam 1 of the reverse construction area have widening sections. The top of the internal top of the structural beam 1 of the reverse construction area has an upper longitudinal reinforcement 10. The bottom of the internal bottom of the structural beam 1 of the reverse construction area has a lower longitudinal reinforcement 11. The two sides of the widening section are respectively provided with construction sections. According to the stress characteristics of the structure at different construction stages, the settlement post-cast strip treatment method is adopted accordingly.

[0027] The widening section includes two beam side widening zones 5, which are fixedly connected to the left and right sides of the structural beam 1 in the reverse construction area. The bottom side of each beam side widening zone 5 has a portion 6 below the bottom of the slab. Multiple additional upper longitudinal reinforcement bars 12 are embedded at the top of the beam side widening zone 5. Multiple additional lower longitudinal reinforcement bars 13 are embedded at the bottom of the portion 6 below the bottom of the slab. Multiple additional web reinforcement bars 14 are embedded on both the left and right sides of the portion 6 below the bottom of the slab. PVC pipes 9 are embedded at the top of adjacent sides of the portions 6 below the bottom of the slab. Multiple additional web reinforcement bars 14 are installed at the rear top of the top side of each beam side widening zone 5. The widened area is reinforced with additional stirrups 16, and beam stirrups 15 are nested inside the widened area additional stirrups 16. Several of the widened area additional stirrups 16 are located on the top side of the structural slab 4 within the settlement post-cast strip range, and the outer wall is fitted with large perimeter stirrups 17 of the widened area. The front end of the top side of the widened area 5 on the beam side is equipped with additional perimeter stirrups 18 of the widened area end. By not pouring the beams within the post-cast strip range during the reverse construction of the underground structure, the widened area is added to the side of the structural beam, and the post-cast strip in the structural slab area is temporarily closed, which solves the problem of horizontal force transmission of the structure during the reverse construction stage of the basement, and at the same time meets the force requirements of the basement roof slab as an excavation platform, soil removal passage and material storage yard.

[0028] The construction section includes two reverse-operation area structural slabs 3, which are fixedly connected to the opposite side of the widened area 5 on the two beams. The interior of the two reverse-operation area structural slabs 3 is penetrated by a structural slab 4 within the settlement post-cast strip. Both ends of the settlement post-cast strip structural slab 4 are penetrated by internal force-transmitting steel 8. An expansion sealing strip 20 is embedded at the intersection of the reverse-operation area structural slab 3 and the settlement post-cast strip structural slab 4. Temporary supports 21 are installed on the bottom side of the reverse-operation area structural slab 3. Reinforcing steel bars 19 are provided at the rear end of the reverse-operation area structural slab 3.

[0029] Working principle: The specific construction steps are as follows:

[0030] Step 1: Install the formwork for the structural beam 1 and structural slab 3 in the reverse construction area according to the design drawings. At the same time, set up a widening zone 5 on the side of the beam. The dimensions and reinforcement of the widening zone 5 on the side of the beam must be able to ensure the horizontal and vertical force transmission requirements of the structure before the concrete of the structural beam 2 in the post-construction strip area is poured after settlement. The length of the widening zone 5 on the side of the beam is L1+L+L1, where L is the width of the post-construction strip, and L1 should meet the requirements for the lap length of the reinforcing bars. The width b1 of the widening zone on the side of the beam is determined according to the width b of the structural beam and the actual stress requirements. The height of the widening zone is the same as the height of the structural beam.

[0031] The second step is to tie the reinforcement bars of the beams, slabs, and the widened areas on the sides of the beams. The reinforcement bars are installed continuously in the pouring strip after settlement. Additional reinforcement bars are set in the widened areas. The additional reinforcement bars consist of the additional upper longitudinal bars 12, the additional lower longitudinal bars 13, the additional web bars 14, the additional stirrups 16, the outer perimeter stirrups 17, and the outer perimeter stirrups 18 at the ends of the widened areas. All reinforcement in the widened areas must meet the actual stress requirements.

[0032] The third step is to set up the load-bearing steel 7 in the beam and the load-bearing steel 8 in the slab after the settlement. The cross-sectional dimensions of the load-bearing steel are determined according to the actual stress. PVC pipes 9 are pre-embedded for later cutting off the part 6 below the bottom of the slab in the widened area on the side of the beam.

[0033] Step 4: Pour concrete for structural beam 1, structural slab 3, and widened area 5 on the side of the beam in the reverse construction area. Pour concrete for structural slab 4 in the construction strip area after settlement. Do not pour concrete for structural beam 2 in the construction strip area after settlement.

[0034] Step 5: Complete the construction of the entire basement structure according to the design requirements;

[0035] Step 6: Before the construction of the above-ground tower, temporary supports 21 shall be installed on both sides of the post-settlement pouring strip. The supports shall extend all the way to the bottom slab of the structure.

[0036] Step 7: Use the pre-embedded PVC pipe 9 to cut off the part 6 below the bottom of the widened area of ​​the beam side, and at the same time chisel away the concrete of the structural slab 4 in the area of ​​the settlement pouring strip. During the chiseling process, retain the slab reinforcement 19.

[0037] Step 8: After the post-cast strips of each basement level have been treated in accordance with Step 7, construction of the above-ground tower will begin.

[0038] Step 9: After the construction of the above-ground tower is completed and the settlement is stable, the structural beam 2 and the structural slab 4 within the settlement pouring strip area shall be poured with one grade higher shrinkage compensation concrete to ensure compaction. For the basement roof slab, an expansion water-stop strip 20 shall be embedded in the slab before pouring.

[0039] Step 10: After the concrete in the post-settlement strip reaches the design strength, remove the temporary support 21.

[0040] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A post-settlement pour strip structure in a top-down method engineering, characterized by, The structure includes a reverse-construction area structural beam (1), with an internal force-transmitting steel (7) at the center of the reverse-construction area structural beam (1), and a settlement-post-cast strip area structural beam (2) at the middle of the reverse-construction area structural beam (1). The settlement-post-cast strip area structural beam (2) is fitted onto the outer wall of the internal force-transmitting steel (7). Both sides of the reverse-construction area structural beam (1) have widening sections. The top of the reverse-construction area structural beam (1) has upper longitudinal reinforcement (10), and the bottom of the reverse-construction area structural beam (1) has lower longitudinal reinforcement (11). Construction sections are provided on opposite sides of the widening sections on both sides.

2. The post-settlement post-cast strip structure in top-down construction method according to claim 1, wherein, The widening section includes two beam side widening areas (5) that are fixedly connected to the left and right sides of the structural beam (1) in the reverse construction area. The bottom side of the beam side widening area (5) is provided with a part (6) below the bottom of the beam side widening area plate. Multiple additional upper longitudinal bars (12) are embedded in the top of the beam side widening area (5). Multiple additional lower longitudinal bars (13) are embedded in the bottom of the part (6) below the bottom of the beam side widening area plate. Multiple additional waist bars (14) are embedded in both the left and right sides of the part (6) below the bottom of the beam side widening area plate. PVC pipes (9) are embedded in the top of the two beam side widening areas below the bottom of the plate on the same side.

3. The post-settlement post-cast strip structure in a top-down method engineering according to claim 2, characterized in that, The construction section includes two reverse construction area structural plates (3) that are fixedly connected to the opposite side of the two beam side widening areas (5). The interior of the two reverse construction area structural plates (3) is penetrated by a settlement post-pouring strip range structural plate (4). The left and right ends of the settlement post-pouring strip range structural plate (4) are penetrated by internal force transmission steel (8).

4. The post-sinking strip structure in a top-down method engineering according to claim 3, characterized in that, An expansion sealing strip (20) is embedded at the intersection of the reverse construction area structural slab (3) and the settlement post-cast strip area structural slab (4).

5. The post-settlement post-cast strip structure in a top-down method engineering according to claim 3, characterized in that, Temporary supports (21) are installed on the bottom side of the reverse operation area structural plate (3).

6. The post-settlement post-cast strip structure in a top-down method engineering according to claim 3, characterized in that, The rear end of the reverse-operation area structural slab (3) is provided with slab reinforcement (19).

7. The post-settlement post-cast strip structure in a top-down method engineering according to claim 2, characterized in that, Multiple additional stirrups (16) are installed on the top rear end of the widened area (5) of the beam side. Beam stirrups (15) are nested inside the additional stirrups (16). Several additional stirrups (16) are located on the top side of the structural slab (4) within the settlement and the outer wall is fitted with large stirrups (17) of the outer perimeter of the widened area.

8. The post-settlement post-cast strip structure in a top-down method engineering according to claim 7, characterized in that: The top front end of the widened area (5) on the side of the beam is equipped with additional large outer stirrups (18) at the end of the widened area.

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