Basement storey-adding construction method

Abstract

The invention relates to the technical field of building construction, and provides a basement storey-adding construction method aiming at the situation that an existing supporting system of a basement is easily affected when storey-adding deepening is conducted on a traditional basement structure. The soil body at the bottom of the existing basement is excavated downwards to the designed elevation of the new basement, so that a foundation pit is formed; s2, pouring construction of a new ring beam: pouring and constructing the new ring beam at the bottom of the existing ring beam; s3, new wall body pouring, wherein a new wall body is poured and constructed between the new ring beam and the existing ring beam; s4, pouring construction of a new ground beam: pouring and constructing the new ground beam below the existing ground beam so as to connect two adjacent supporting columns; and S5, dismantling construction of the existing ground beam. The supporting system has the effect of limiting the influence on the existing supporting system during storey-adding deepening construction of the basement.

Description

Technical Field

[0001] This application relates to the field of building construction, and particularly to a method for adding a basement floor. Background Art

[0002] In the renovation project of old houses, the basement space of old buildings often needs to be deepened due to the need for functional upgrading to further increase the basement floor height.

[0003] Currently, when adding a basement floor to an existing basement, it is necessary to dig down the original soil body of the basement to the design elevation of the new basement. At the same time, during the construction of soil excavation, it is necessary to demolish the existing ground beam (non-load-bearing) between two adjacent support columns of the basement and re-pour a new ground beam later.

[0004] Regarding the above related technologies, the existing ground beam mainly plays a role in connecting and stabilizing two adjacent support columns. The conventional construction method is to demolish the existing ground beam while excavating the soil body, which is very likely to affect the stability of the basement support columns. Therefore, there is room for improvement. Summary of the Invention

[0005] In order to limit the impact of adding a basement floor on the existing basement support system during construction, this application provides a method for adding a basement floor.

[0006] A method for adding a basement floor provided by this application adopts the following technical solutions: A method for adding a basement floor includes the following steps: S1: Foundation pit construction: Demolish the existing basement floor structure and dig down the soil body at the bottom of the existing basement to the design elevation of the new basement to form a foundation pit; S2: Pouring construction of a new ring beam: Pour and construct a new ring beam at the bottom of the existing ring beam; S3: Pouring of a new wall: Pour and construct a new wall between the new ring beam and the existing ring beam; S4: Pouring construction of a new ground beam: Pour and construct a new ground beam below the existing ground beam to connect two adjacent support columns; S5: Demolition construction of the existing ground beam.

[0007] By adopting the above technical solution, after the construction of the new ground beam is completed, the existing ground beam is demolished. The new ground beam is used to tie, support and limit the two adjacent support columns, reducing the situation that the overall stability of the support columns is affected due to the lack of horizontal constraints between the two adjacent support columns during the subsequent demolition of the existing ground beam. Compared with the conventional construction plan, it is possible to effectively limit the impact of the demolition construction on the existing support columns in the basement while demolishing the existing ground beam. At the same time, by constructing a new ring beam at the bottom of the existing ring beam and constructing a new wall between the new ring beam and the existing ring beam, it is beneficial to strengthen the support structure of the basement, further enhancing the overall strength of the basement support system and improving the construction safety.

[0008] Preferably, in step S5, when the existing ground beam is demolished, a support frame for supporting the existing ground beam is erected on the new ground beam, and then the existing ground beam is cut off by a wire saw cutting machine.

[0009] By adopting the above technical solution, using the support frame to support and limit the existing ground beam to be demolished is beneficial to restricting the situation that the existing ground beam collapses and damages the new ground beam during the subsequent demolition construction of the existing ground beam.

[0010] Preferably, the support frame includes a base, a support is erected on the top of the base, and a number of first support oil cylinders are vertically erected upward corresponding to the support. The piston rod of the first support oil cylinder is connected to the bottom of the support. In step S5, after the base is installed above the new ground beam, the support is driven to move upward by the first support oil cylinder on the base until the support abuts against the bottom of the existing ground beam.

[0011] By adopting the above technical solution, the support frame can be firmly supported on the existing ground beam by driving the support to abut against the bottom of the existing ground beam to be demolished by the first support oil cylinder. At the same time, the setting of the first support oil cylinder enables the overall height position of the support to be adjustable, which is beneficial for the support frame to adjust the position of the support according to the specific conditions of each old beam, so that the support can better abut against the bottom of the corresponding old beam.

[0012] Preferably, second support oil cylinders are vertically installed downward on both opposite sides of the base. In step S5, after the base is installed above the new ground beam, the piston rods on both opposite sides of the base are driven by the second support oil cylinders to abut against the bottom of the foundation pit.

[0013] By adopting the above technical solution, by arranging the second support cylinders on the opposite sides of the base, when the support is subsequently supported above the new ground beam, the piston rods of the second support cylinders on the opposite sides of the support are driven to extend and abut against the bottom of the foundation pit until the support is lifted off the new ground beam. Several second support cylinders are used as the support points of the support to limit the contact between the support and the new ground beam, avoiding the situation that the load is directly applied to the new ground beam after the support is stressed, resulting in the compression damage of the new ground beam.

[0014] Preferably, limiting plates are vertically connected to both opposite sides of the support, and a groove-shaped space for the existing ground beam to be embedded is formed between the support and the limiting plates on both opposite sides. Limiting cylinders are vertically supported on both limiting plates, and the limiting cylinders on both limiting plates are arranged oppositely; In step S5, the support is driven by the first support cylinder to abut against the bottom of the existing ground beam, and the two limiting plates are respectively located on both opposite sides of the existing ground beam. Then, the piston rods of the limiting cylinders are driven to abut against the side surface of the existing ground beam.

[0015] By adopting the above technical solution, the existing ground beam during the demolition process is clamped and limited by the limiting cylinders of the limiting plates on both opposite sides of the support plate, restricting the situation that the old beam moves relative to the support due to stress when the two ends of the old beam are cut by a wire saw later.

[0016] Preferably, in step S1, the excavation of the foundation pit soil is carried out in a layered manner. After each layer of soil is excavated, the soil structure around the foundation pit is reinforced by pipe grouting.

[0017] By adopting the above technical solution, it is beneficial to improve the stability of the foundation pit during the construction process and limit the subsequent collapse of the soil around the foundation pit during the construction process.

[0018] Preferably, in step S3, before the new wall is poured, a reinforcement baffle is supported between the existing ring beam and the new ring beam, and the reinforcement baffle is attached to the soil on the side of the foundation pit.

[0019] By adopting the above technical solution, on the one hand, the reinforcement baffle can be used to reinforce the soil on the side of the foundation pit, further improving the structural stability of the soil on the side of the foundation pit; on the other hand, the reinforcement baffle can be used as the side formwork during the subsequent pouring process of the new wall, facilitating the better shaping of the new wall and restricting the leakage of the poured concrete slurry through the cracks in the foundation pit soil.

[0020] Preferably, an annular flexible bladder is sleeved on the outer periphery of the reinforcement baffle; In step S3, after the reinforcement baffle is supported, concrete slurry is injected into the annular flexible bladder to make the annular flexible bladder expand and abut against the existing ring beam, the new ring beam, and the two adjacent support columns connected to the ring beam.

[0021] By adopting the above technical solutions, a ring-shaped flexible capsule is sleeved on the outer periphery of the reinforcement baffle, and after the support is completed, concrete slurry is injected into the ring-shaped flexible capsule. On the one hand, it is beneficial to improve the connection stability between the reinforcement baffle and the existing ring beam, the new ring beam and the support column. At the same time, by utilizing the good deformation ability of the ring-shaped flexible capsule and the injected concrete slurry, the ring-shaped flexible capsule can form a sealed contact surface with each contact structure after expansion, effectively improving the sealing performance of the overall structure and restricting the leakage of concrete slurry through the gaps between the reinforcement baffle and each structure when pouring the new wall subsequently.

[0022] In summary, the present application includes at least one of the following beneficial technical effects: 1. By demolishing the existing ground beam after the new ground beam is poured, the new ground beam is used to tie, support and limit the adjacent two support columns, effectively restricting the situation that the existing ground beam is likely to affect the existing support columns in the basement during demolition.

[0023] 2. Before demolishing the existing ground beam, a support frame is erected at the bottom of the existing ground beam, and the support frame is used to support and limit the existing ground beam, restricting the movement or deviation of the existing ground beam due to force when using a wire saw cutting machine to cut both ends of the existing ground beam, ensuring the stability and safety of the demolition construction.

[0024] 3. Before pouring the new wall between the new ring beam and the existing ring beam, a reinforcement baffle is erected on the side of the new ring beam and the existing ring beam facing the foundation pit soil. On the one hand, it is beneficial to further reinforce and limit the foundation pit soil. On the other hand, the reinforcement baffle can be used as a formwork structure for pouring the subsequent new wall, which is beneficial to the formation of the new wall and restricts the leakage of the new wall concrete slurry through the cracks in the side soil of the foundation pit. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a schematic diagram showing the state when constructing the foundation pit in the embodiment of the present application.

[0026] Figure 2 is a schematic diagram showing the state when constructing the new ring beam at the bottom of the foundation pit in the embodiment of the present application.

[0027] Figure 3 is a schematic diagram showing the state when constructing the new wall in the embodiment of the present application.

[0028] Figure 4 is Figure 3 an enlarged schematic diagram of part A in

[0029] Figure 5 is a schematic diagram showing the state when tying the steel bar structure of the new ground beam in the embodiment of the present application.

[0030] Figure 6 It is a schematic diagram showing the state when pouring a new ground beam in an embodiment of the present application.

[0031] Figure 7 It is a schematic diagram showing the state when demolishing an existing ground beam in an embodiment of the present application.

[0032] Figure 8 It is a schematic diagram showing the structure of a support frame in an embodiment of the present application.

[0033] Explanation of reference numerals: 1, foundation pit; 2, support column; 3, existing ring beam; 31, new ring beam; 32, reinforcement baffle; 320, annular limiting groove; 321, annular flexible capsule; 4, existing ground beam; 41, new ground beam; 5, support frame; 51, base; 52, support; 53, first support oil cylinder; 54, limiting plate; 55, limiting oil cylinder; 56, second support oil cylinder. Detailed implementation manners

[0034] The following further elaborates on the present application in conjunction with the attached Figures 1-8 drawings.

[0035] An embodiment of the present application discloses a method for basement additional storey construction, including the following steps: S1: Construction of foundation pit 1: Refer to Figure 1 and Figure 2 , demolish the existing basement floor structure, and dig downward the soil at the bottom of the existing basement to the designed elevation of the new basement; the specific steps are as follows: S1.1: Demolish the existing basement floor structure by means of equipment such as pneumatic picks. The part of the floor structure close to the existing ground beam 4 is demolished manually using tools such as iron chisels to limit the damage to the existing ground beam 4. S1.2: Use an excavator to layer - by - layer excavate the soil under the existing basement to the designed elevation of the new basement. During this period, after each layer of soil is excavated, the surrounding soil of the foundation pit 1 is reinforced by buried pipe grouting construction to improve the stability of the side soil of the foundation pit 1 and limit the collapse of the surrounding soil of the foundation pit 1. S1.3: Compaction of the bottom of foundation pit 1: Clean the sundries at the bottom of foundation pit 1, and compact the soil at the bottom of foundation pit 1 by a rammer.

[0036] S2: Pouring construction of new ring beam 31: Refer to Figure 2 and Figure 3 , pour and construct a new ring beam 31 at the bottom of the existing ring beam 3; the specific steps are as follows: S2.1: Bind the ring beam steel bar structure between two adjacent support columns 2 on the outer side of the basement structure. S2.2: Pouring of new ring beam 31: Set up the ring beam pouring formwork on the outer periphery of the ring beam steel bar structure and pour concrete to form the new ring beam 31.

[0037] S2.3: Demolish the formwork for casting the ring beam; S2.4: Repeat steps S2.1 to S2.3 until the casting construction of the remaining new ring beam 31 of the remaining basement structure is completed.

[0038] S3: Cast new wall: Cast a new wall between the new ring beam 31 and the existing ring beam 3; the specific steps are as follows: S3.1: Install the reinforcement baffle 32: Set up the reinforcement baffle 32 between the existing ring beam 3 and the new ring beam 31, and make the reinforcement baffle 32 fit against the side soil body of the foundation pit 1.

[0039] Refer to Figure 3 and Figure 4 A circular flexible bladder 321 is sleeved on the outer periphery of the reinforcement baffle 32, a circular limiting groove 320 is provided on the outer periphery of the reinforcement baffle 32 corresponding to the circular flexible bladder 321, the inner peripheral edge of the circular flexible bladder 321 is embedded in the circular limiting groove 320, and a grouting pipe is connected to the outer side of the circular flexible bladder 321.

[0040] In step S3.1, after moving the reinforcement baffle 32 between the existing ring beam 3 and the new ring beam 31, inject concrete slurry into the circular flexible bladder 321 through the grouting pipe on the outer side of the circular flexible bladder 321, so that the circular flexible bladder 321 expands and abuts against the existing ring beam 3, the new ring beam 31 and the support column 2, realizing the sealing of the gaps between the reinforcement baffle 32 and the above-mentioned components.

[0041] S3.2: Bind the wall steel bars: Bind the wall steel bar structure between the existing ground beam 4 and the new ground beam 41; S3.3: Set up the formwork for casting the wall and pour the concrete slurry to form a new wall.

[0042] By casting the new ring beam 31 at the bottom of the existing ring beam 3 and casting a new wall between the existing ring beam 3 and the new ring beam 31, it is beneficial to improve the overall stability of the basement structure support system.

[0043] By setting up the reinforcement baffle 32 between the existing ring beam 3 and the new ring beam 31, on the one hand, it is beneficial to further reinforce the side soil body of the foundation pit 1 to further improve the overall stability of the side soil body of the foundation pit 1 and limit the collapse of the side soil body of the foundation pit 1 due to construction disturbance. On the other hand, the reinforcement baffle 32 can cooperate with the circular flexible bladder 321 that expands after subsequent grouting to serve as the side formwork during the casting of the new wall, which is beneficial to the formation of the concrete slurry of the new wall and limits the leakage of the concrete slurry during the casting of the new wall through the cracks in the side soil body of the foundation pit 1.

[0044] S4: Casting construction of the new ground beam 41: Refer to Figure 5 and Figure 6, a new ground beam 41 is cast and constructed below the existing ground beam 4 to connect two adjacent support columns 2; the specific steps are as follows: S4.1: Tie the ground beam steel structure at the bottoms of two support columns 2 connected to the existing ground beam 4; S4.2: Set up the formwork for casting the ground beam and pour concrete to form the new ground beam 41; S4.3: Remove the formwork for casting the ground beam.

[0045] S5: Construction of removing the existing ground beam 4: Refer to Figure 7 and Figure 8 , set up a support frame 5 for supporting the existing ground beam 4 on the new ground beam 41, and then cut both ends of the existing ground beam 4 by a wire saw cutting machine.

[0046] The support frame 5 includes a base 51, a support 52 is provided above the base 51, two first support cylinders 53 are vertically and upwardly installed on the base 51 corresponding to the support 52, and the piston rods of the first support cylinders 53 are connected to the bottom of the support 52.

[0047] Limit plates 54 are perpendicularly welded to both opposite sides of the support 52, and a groove-shaped space for the existing ground beam 4 to be embedded is formed between the support 52 and the two limit plates 54; a number of limit cylinders 55 are perpendicularly installed on the mutually facing sides of the two limit plates 54, and the limit cylinders 55 on the two limit plates 54 are arranged oppositely, and the piston rods of the limit cylinders 55 pass through the corresponding limit plates 54.

[0048] A number of second support cylinders 56 are vertically and downwardly installed on both opposite sides of the base 51.

[0049] The specific steps of step S5 are as follows: S5.1: Positioning of the support frame 5: Move the base 51 above the new ground beam 41 by a crane, and make the second support cylinders 56 on both opposite sides of the base 51 be respectively located on both opposite sides of the new ground beam 41, and drive the piston rods of the second support cylinders 56 to move downward until they abut against the bottom of the foundation pit 1; S5.2: Support of the existing ground beam 4: Drive the support 52 to move upward by the first support cylinder 53, so that when the support 52 abuts against the bottom of the existing ground beam 4, the limit plates 54 on both opposite sides of the support 52 are respectively located on both opposite sides of the existing ground beam 4; S5.3: Limiting of the existing ground beam 4: Drive the piston rods of the limit cylinders 55 on the limit plates 54 to abut against the side surface of the existing ground beam 4 to realize clamping and limiting of the existing ground beam 4; S5.4: Cut both ends of the existing ground beam 4 by a wire saw cutting machine; S5.5: Release the limit of the existing ground beam 4: Drive the piston rod of the limit cylinder 55 to disengage from the cut existing ground beam 4; S5.6: Lift the cut existing ground beam 4 from the support 52 by a crane: S5.6: The first support oil cylinder 53 drives the support 52 to move downward and reset, and a crane lifts the entire support frame 5 from the new ground beam 41; S5.7: Adopt a construction sequence of demolishing one and leaving one, and demolish the remaining existing ground beams 4.

[0050] Before demolishing the existing ground beam 4, install a support frame 5 at the bottom of the existing ground beam 4, and use the support frame 5 to support and limit the existing ground beam 4, effectively restricting the situation that the existing ground beam 4 falls due to the loss of connection constraints during the subsequent demolition process, which is beneficial to improving the safety of the existing ground beam 4 during the demolition process.

[0051] By making the second support oil cylinders 56 on the relative two sides of the support 52 drive their piston rods to abut against the bottom substrate of the foundation pit 1, and using the second support oil cylinders 56 as the fulcrums of the support 52, restrict the situation that after the subsequent support frame 5 is stressed, the load is transmitted to the new ground beam 41 through the support 52, causing the new ground beam 41 to be damaged by compression.

[0052] In this application, after constructing the new ground beam 41 first and then demolishing the existing ground beam 4, when demolishing the existing ground beam 4, the new ground beam 41 can be used to connect and restrain the two adjacent support column bodies 2, effectively reducing the impact on the basement support system when demolishing the existing ground beam 4.

[0053] The above are all the preferred embodiments of this application, and the protection scope of this application is not limited accordingly. Therefore, all equivalent changes made according to the structure, shape, and principle of this application shall be covered within the protection scope of this application.

Claims

1. A basement floor-adding construction method, characterized by: The following steps are involved: S1: Construction of foundation pit (1): demolish the existing basement floor structure, and excavate the existing basement bottom soil downward to the design elevation of the new basement to form the foundation pit (1); S2: Casting construction of new ring beam (31): Casting a new ring beam (31) at the bottom of the existing ring beam (3); S3: New wall casting: Casting a new wall between the new ring beam (31) and the existing ring beam (3); S4: Casting of new ground beam (41): Casting of new ground beam (41) below the existing ground beam (4) to connect two adjacent support columns (2); S5: Dismantling of existing ground beam (4).

2. A basement floor-adding construction method according to claim 1, characterized in that: In step S5, when the existing ground beam (4) is removed, a support frame (5) for supporting the existing ground beam (4) is set on the new ground beam (41), and then the existing ground beam (4) is cut by a rope saw cutting machine.

3. A basement floor-adding construction method according to claim 2, characterized in that: The support frame (5) comprises a base (51), a support (52) is supported on the top of the base (51), a plurality of first support cylinders (53) are supported vertically upward on the base (51) corresponding to the support (52), and the piston rods of the first support cylinders (53) are connected to the bottom of the support (52); In step S5, after the base (51) is installed above the new ground beam (41), the support (52) is moved upward by the first supporting oil cylinder (53) on the base (51) until the support (52) abuts against the bottom of the existing ground beam (4).

4. A basement floor-adding construction method according to claim 3, characterized in that: Second supporting oil cylinders (56) are vertically installed downwards on opposite sides of the base (51); In step S5, after the base (51) is installed above the new ground beam (41), the second supporting oil cylinders (56) on opposite sides of the base (51) drive their piston rods to abut against the bottom of the foundation pit (1).

5. A basement floor-adding construction method according to claim 3, characterized in that: The support (52) is vertically connected to limiting plates (54) on opposite sides, the support (52) and the limiting plates (54) on opposite sides form a groove-shaped space for the existing ground beam (4) to be embedded, and limiting oil cylinders (55) are vertically supported on the two limiting plates (54), and the limiting oil cylinders (55) on the two limiting plates (54) are arranged opposite to each other; In step S5, the first supporting oil cylinder (53) drives the support (52) to abut against the bottom of the existing ground beam (4), and the two limiting plates (54) are respectively located on the opposite sides of the existing ground beam (4), and then the limiting oil cylinder (55) drives its own piston rod to abut against the side of the existing ground beam (4).

6. A basement floor-adding construction method according to claim 1, characterized in that: In step S1, the excavation of the soil of the foundation pit (1) is carried out in a layered excavation manner. After each layer of soil is excavated, the soil structure around the foundation pit (1) is reinforced by buried pipe grouting.

7. A basement floor-adding construction method according to claim 1, characterized in that: In step S3, before the new wall is poured, a reinforcement baffle (32) is supported between the existing ring beam (3) and the new ring beam (31), and the reinforcement baffle (32) is made to fit the soil on the side of the foundation pit (1).

8. A basement floor-adding construction method according to claim 7, characterized in that: The outer periphery of the reinforcement baffle (32) is sleeved with an annular flexible capsule (321); In step S3, after the reinforcement baffle (32) is installed, concrete slurry is injected into the annular flexible bladder (321) so that the annular flexible bladder (321) expands and abuts against the existing ring beam (3), the new ring beam (31) and two adjacent support columns (2) connected by the ring beam.

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