Construction method of underground deep foundation pit for circulating water pump room and pit wall formwork support structure

Abstract

The present invention provides a method for constructing a deep underground foundation pit of a circulating water pump room and a pit wall template support structure. The construction method includes: a. digging a guide wall groove; b. tying a guide wall steel mesh; c. supporting a guide wall template; d. pouring guide wall concrete; e. removing the template; f. backfilling mud; g. digging a ground-connected wall groove; h. hanging a steel cage into the ground-connected wall groove; i. placing a concrete conduit; j. pouring concrete into the ground-connected wall groove; k. pouring all the ground-connected walls; l. excavating a foundation pit groove; m. setting a horizontal H-shaped steel on the wall surface of the ground-connected wall in the groove, and supporting a cross bracing beam between the vertical plates on the outside of the two H-shaped steels; n. pouring the bottom surface of the groove of the foundation pit; o. installing a foundation pit steel cage; p. supporting an inner template; q. pouring a foundation pit wall; r. installing a steel cage of a foundation pit wall located above a section adjacent to the completed section, and pouring concrete. The present invention has simple procedures and high efficiency.

Description

Technical Field

[0001] The invention relates to the field of building construction, in particular to a method for constructing an underground deep foundation pit for a circulating water pump room and a pit wall template supporting structure. Background Art

[0002] The underground structure of the circulating water pump room is complex and the construction process requires high requirements. There are not only complex trenching projects, but also unconventional earthwork excavation projects and support projects, especially in the process of deep foundation pits underground for circulating water pump rooms. Generally, before pouring the deep foundation pit underground for the pump room, the ground-connected wall outside the foundation pit is poured first, and then the ground-connected wall is set on the outer wall of the pit. The ground-connected wall of the deep foundation pit is generally deeper, and the greater the depth, the greater the underground humidity, which prolongs the solidification time of the ground-connected wall of the deep foundation pit. In order to prevent the ground-connected wall from tilting due to force when it is not completely solidified, the ground-connected wall needs to be supported before pouring the deep foundation pit. However, the existing support structure is complex, which directly affects the construction efficiency of the deep foundation pit. Summary of the invention

[0003] One of the purposes of the present invention is to provide a method for constructing an underground deep foundation pit of a circulating water pump room, so as to solve the problem of low construction efficiency of the existing underground deep foundation pit of a circulating water pump room.

[0004] The second purpose of the present invention is to provide a foundation pit wall formwork support structure of an underground deep foundation pit of a circulating water pump room to simplify the foundation pit wall formwork support structure.

[0005] One of the purposes of the present invention is achieved in this way: a method for constructing an underground deep foundation pit of a circulating water pump room comprises the following steps:

[0006] a. Measure and lay out the lines on the ground where the deep foundation pit is to be dug according to the drawings, and use excavators and crushers to dig the guide wall trenches for the ground-connected walls surrounding the foundation pit;

[0007] b. After the guide wall groove is dug, tie the guide wall steel mesh along the groove wall of the guide wall groove;

[0008] c. After the guide wall steel mesh is tied, the guide wall formwork for pouring the guide wall is set up;

[0009] d. After the guide wall formwork is set up, pour concrete into the guide wall formwork;

[0010] e. After the concrete solidifies, remove the guide wall formwork;

[0011] f. Use bentonite to make mud, expand for more than 24 hours and backfill the bentonite mud into the guide wall groove after passing the test;

[0012] g. Use trenching machines to dig trenches for pouring ground-connected walls;

[0013] h. Use a truck crane to hoist the steel cage into the trench of the ground-connected wall;

[0014] i. Then use a truck crane to insert a concrete conduit into the ground-connected wall groove, and the concrete conduit is inserted into the steel cage in the ground-connected wall groove;

[0015] j. After the concrete conduit is installed, pour concrete into the ground-connected wall groove through the concrete conduit;

[0016] k. According to steps g~j, pour all the ground-connected walls surrounding the foundation pit and wait for the concrete of the ground-connected walls to solidify;

[0017] 1. After the concrete of the ground-connected wall solidifies, a pit of the foundation pit is excavated in the area enclosed by the ground-connected wall, so that the wall surface of the ground-connected wall on one side of the pit is exposed and used as the outer formwork for pouring the foundation pit wall;

[0018] m. The pit of the foundation pit is excavated in sections in the vertical direction. For each section of the pit, a horizontal H-shaped steel is set on the wall surface of each ground-connected wall exposed in the pit. The H-shaped steels on the ground-connected walls arranged opposite to each other are located at the same horizontal position, and the H-shaped steels on the ground-connected walls arranged opposite to each other have different heights. One of the vertical plates of the H-shaped steel is fixed on the wall surface of the ground-connected wall to form an upper support groove opening upward at the upper end of the H-shaped steel and a lower limit groove opening downward at the lower end. A cross bracing beam is provided between the other vertical plate of the H-shaped steel and the vertical plate on the outer side of the opposite H-shaped steel;

[0019] n. After the pit of the foundation pit is dug, the H-shaped steel and the cross bracing beam are laid out, the bottom surface of the pit of the foundation pit is poured;

[0020] o. After the concrete at the bottom of the pit is solidified, install a steel cage of the pit wall between the lowest H-shaped steel and the bottom of the pit, so that the upper end of the steel cage is stuck in the lower limit groove of the lowest H-shaped steel;

[0021] p. Then, the inner formwork of the foundation pit wall on one side of the pit, on which the steel cage section is installed in the previous step, is supported, and a concrete pouring opening is opened at the upper end of the inner formwork;

[0022] q. pouring the foundation pit wall located at the template section through the concrete pouring port on the inner template;

[0023] r. Install the steel cage of the pit wall of the adjacent section above the section where the casting is completed, so that the lower end of the steel cage of this section is stuck in the upper support groove of the H-shaped steel below the section, and the upper end is stuck in the lower limit groove of the H-shaped steel above the section, and then support the inner formwork of the pit wall of this section, and pour concrete into this section through the concrete pouring port of the inner formwork;

[0024] s. Repeat step r until the entire foundation pit wall is poured. After the concrete solidifies, remove the outer formwork of all the foundation pit walls on one side of the pit, and the pouring of the underground foundation pit of the pump house is completed.

[0025] The H-shaped steel is fixed on the wall surface of the ground-connected wall by screws.

[0026] There are four cross bracing beams between each pair of H-shaped steels arranged opposite to each other, and the four cross bracing beams are evenly arranged along the length direction of the H-shaped steels.

[0027] The present invention first casts the ground-connected wall, and then uses the wall surface of the ground-connected wall as the outer template of the foundation pit wall to cast the pit wall of the foundation pit. The inner lining steel bars of the pit wall of the foundation pit of the present invention are arranged in the form of H-shaped steel combined with a steel cage. Such an arrangement not only provides a support point for the cross bracing beam, preventing the wall surface of the ground-connected wall from losing support due to the pit trench of the foundation pit, and thus tipping or deforming, but also the H-shaped steel is finally cast in the pit wall of the foundation pit, and as a part of the inner lining steel cage, the process of disassembly in the later stage is eliminated, which helps to improve the construction efficiency. In addition, during the casting process of the foundation pit wall, since the H-shaped steel has a supporting effect on the upper foundation pit wall, during the casting process of the foundation pit wall, there is no need to consider whether the foundation pit wall between the lower H-shaped steels is solidified, and the casting work of the foundation pit wall between the upper H-shaped steels can be carried out, which helps to shorten the construction period and save construction costs.

[0028] The second object of the present invention is achieved as follows: a pit wall template support structure of an underground deep foundation pit of a circulating water pump room, with the inner wall surface of the ground-connected wall located on the side of the foundation pit surrounding the foundation pit as the outer template of the pit wall, and a plurality of H-shaped steels are fixedly arranged on the inner wall surface of each ground-connected wall at intervals in the up and down directions, each of the H-shaped steels is arranged horizontally, and a side vertical plate thereof is fitted with the inner wall surface of the ground-connected wall to form an upper support groove opening upward and a lower limit groove opening downward; the number of the H-shaped steels on the ground-connected walls arranged opposite to each other is equal and is arranged symmetrically A cross bracing beam is supported between the outer vertical plates of two H-shaped steels at the same height on the two opposite ground-connected walls, and the H-shaped steels on the non-opposite ground-connected walls are set at different heights; the inner lining steel cage of each pit wall of the pit foundation is divided into several pieces, which are installed above and below the H-shaped steel on the ground-connected wall, and the upper end of each steel cage is embedded in the lower limit groove of the H-shaped steel on the corresponding side, and the lower end is embedded in the upper support groove of the H-shaped steel on the corresponding side; the inner side formwork of the foundation pit wall fits the plate surface of the side vertical plate supporting the cross bracing beam, and a concrete pouring port is opened on the inner formwork.

[0029] The H-shaped steel is fixed on the wall surface of the ground-connected wall by screws.

[0030] There are four cross bracing beams between each pair of H-shaped steels arranged opposite to each other, and the four cross bracing beams are evenly arranged in the length direction of the H-shaped steels.

[0031] The present invention can effectively solve the problem of supporting and removing the template of the wall of the underground deep foundation pit of the circulating water pump room. During the construction process, there is no need to wait until the structural strength meets the requirements before removing the template of the lower layer to start construction, and the construction speed is fast. The present invention is provided with an H-shaped steel supporting the cross bracing beam, and the H-shaped steel is finally cast in the wall of the foundation pit without disassembly, so that the construction process of the foundation pit is simple, the construction cost is reduced, the efficiency is improved, the safety hazard is reduced and it is easy to implement, and it has a high promotion value. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a structural schematic diagram of the present invention.

[0033] In the figure: 1. Underground soil layer; 2. Ground-connected wall; 3. H-shaped steel; 4. Cross bracing beam; 5. Foundation pit wall. DETAILED DESCRIPTION

[0034] Embodiment 1: A method for constructing a deep underground foundation pit for a circulating water pump room.

[0035] like Figure 1 As shown, the present invention is a construction method for setting a deep foundation pit underground in a circulating water pump room, comprising the following steps:

[0036] a. Select the construction location of the underground deep foundation pit of the circulating water pump room on the underground soil layer 1, use a total station to lay out the lines on the ground where the deep foundation pit is dug according to the construction drawings, and then use an excavator and a crusher to dig the guide wall groove of the ground-connected wall along the laid-out lines. The ground-connected wall 2 of the present invention is arranged around the foundation pit wall 5, and the inner wall surface of the ground-connected wall 2 is in close contact with the outer wall surface of the foundation pit wall 5.

[0037] b. After the trench of the guide wall is dug, the steel mesh of the guide wall is tied along the groove wall of the guide wall trench. The steel mesh of the guide wall is made of horizontal and vertical crossed steel bars.

[0038] c. After the steel mesh of the guide wall is tied, set up the formwork of the guide wall.

[0039] d. After the guide wall formwork is set up, pour concrete into the formwork.

[0040] e. After the concrete solidifies, remove the formwork of the guide wall.

[0041] f. Collect bentonite to make mud. After the mud has expanded for more than 24 hours and passed the test, backfill the bentonite mud into the guide wall groove to support the guide wall and prevent the guide wall from deformation due to uneven force.

[0042] g. Use a trenching machine to dig a trench in the guide wall trench for pouring the ground-connected wall 2.

[0043] h. After the trench of the ground-connected wall 2 is dug, use a truck crane to lift the steel cage into the trench of the ground-connected wall 2.

[0044] i. Then use a truck crane to hoist a concrete conduit into the groove of the ground-connected wall 2, and the concrete conduit is inserted into the steel cage in the groove of the ground-connected wall 2.

[0045] j. After the concrete conduit is installed, pour concrete into the groove of the ground-connected wall 2 through the concrete conduit.

[0046] k. According to steps g~j, the ground-connected wall 2 surrounding the foundation pit wall 5 is completely poured, and then the concrete of the ground-connected wall 2 is waited to solidify.

[0047] 1. After the concrete of the ground-connected wall 2 solidifies, a trench of the foundation pit is excavated in the area enclosed by the ground-connected wall 2, so that the wall surface of the ground-connected wall 2 on the side of the trench is exposed to be used as the outer formwork for pouring the foundation pit wall 5.

[0048] m. The pit of the foundation pit of the present invention is excavated in sections in the vertical depth direction. For each section of the pit, a horizontal H-shaped steel 3 is set on the wall surface of the ground-connected wall 2 exposed in the pit. The H-shaped steel 3 in this embodiment is fixed to the wall surface of the ground-connected wall 2 by screws. In the present invention, the H-shaped steels 3 on the wall surfaces of the oppositely arranged ground-connected walls 2 are located at the same horizontal position, and the heights of the H-shaped steels on the asymmetrically arranged ground-connected walls 2 are different. The height difference between the two is the radial distance of a cross bracing beam 4, so that interference between the cross bracing beams 4 supported in the cross direction can be prevented. In the present invention, the vertical plate on one side of the H-shaped steel 3 is fixed on the wall surface of the ground-connected wall 2 to form an upper support groove opening upward and a lower limit groove opening downward. A cross bracing beam 4 is supported between the other vertical plate of the H-shaped steel 3 and the vertical plate of the oppositely arranged H-shaped steel 3. The number of cross bracing beams 4 between each pair of H-shaped steels 3 is set according to the length of the H-shaped steel. In this embodiment, four cross bracing beams 4 are arranged between each pair of H-shaped steels 3, and the four cross bracing beams 4 are evenly arranged along the length direction of the H-shaped steels 3. The cross bracing beams 4 have two functions: first, they support and position the H-shaped steels 3; second, they transmit the supporting force to the ground-connected wall 2 through the H-shaped steels 3 to prevent the ground-connected wall 2 from tilting or deforming into the foundation pit due to the action of the underground soil layer 1.

[0049] n. After the pit of the foundation pit is dug, the H-shaped steel 3 on the wall surface of the ground-connected wall 2 in the pit and the cross bracing beam 4 supported outside the H-shaped steel 3 are arranged, the bottom surface of the pit of the foundation pit is poured.

[0050] o. After the concrete on the bottom of the pit is solidified, install a section of the pit wall 5 steel cage (not shown in the figure) between the lowest H-shaped steel 3 and the bottom of the pit, so that the upper end of the section of the steel cage is stuck in the lower limit groove of the lowest H-shaped steel 3.

[0051] p. Then, the inner formwork of the foundation pit wall 5 on which the steel cage section is installed in the previous step and located on one side of the pit is supported, and a concrete pouring port is opened at the upper end of the inner formwork.

[0052] q. Pour the pit wall of the foundation pit located in the template section through the concrete pouring port on the inner template.

[0053] r. After the above steps are completed, you can wait for the concrete poured in the above steps, or you can not wait. Then install the steel cage of the foundation pit wall 5 of the adjacent section above the poured section, so that the lower end of the steel cage of this section is stuck in the upper support groove of the H-shaped steel below the section, and the upper end is stuck in the lower limit groove of the H-shaped steel 3 above the section, and then support the inner side template of the foundation pit wall of this section, and similarly, pour concrete into this section through the concrete pouring port located at the upper end of the inner side template.

[0054] s. Repeat step r until the pit wall of the entire foundation pit is poured. After the concrete of the pit wall of the entire foundation pit solidifies, remove the outer formwork of all the pit walls 5 on one side of the pit, and the pouring work of the entire underground foundation pit of the pump house is completed.

[0055] Embodiment 2: A pit wall formwork support structure for an underground deep foundation pit of a circulating water pump room.

[0056] like Figure 1 As shown, the present invention is to cast the foundation pit wall 5 close to the inner wall surface of the built ground-connected wall 2, that is, during construction, the inner wall surface of the ground-connected wall surrounding the outside of the foundation pit is used as the outer template of the foundation pit wall 5. On the inner wall surface of each ground-connected wall 2, a plurality of H-shaped steels 3 are arranged at intervals in the up and down directions in the depth direction of the foundation pit. Each H-shaped steel 3 is arranged horizontally, and one side of the inner wall is arranged in contact with the inner wall surface of the ground-connected wall 2, so that an upper support groove with an opening upward and a lower limit groove with an opening downward are formed on the H-shaped steel 3. In the present invention, the number of H-shaped steels 3 on the oppositely arranged ground-connected walls 2 is equal, and the H-shaped steels 3 are arranged symmetrically. A cross brace 4 is supported between the side vertical plates on the outer sides of the two H-shaped steels 3 at the same height on the two oppositely arranged ground-connected walls 2, and a plurality of cross brace beams 4 are arranged between each pair of H-shaped steels 3. In this embodiment, four cross brace beams 4 are arranged, and the four cross brace beams 4 are evenly arranged in the length direction of the H-shaped steel 3. The H-shaped steels 3 on the non-oppositely arranged ground-connected walls 2 are arranged at different heights, and the height difference is equal to the radial dimension of a cross bracing beam 4, so that the cross bracing beams 4 arranged in a cross direction can be prevented from interfering with each other.

[0057] The present invention divides the inner lining steel cage of each pit wall of the foundation pit into several pieces, so that they can be installed above and below the H-shaped steel 3 of the ground-connected wall 2. The upper end of each steel cage is embedded in the lower limit groove of the H-shaped steel 3 on the corresponding side, and the lower end is embedded in the upper support groove of the H-shaped steel 3 on the corresponding side. The inner template for pouring the casting cavity of the pit wall 5 is arranged in affixed to the plate surface of the side vertical plate for supporting the horizontal bracing beam 4, and a concrete pouring port is opened on the inner template. By conveying concrete into the concrete pouring port, the pouring work of the pit wall 5 can be completed.

Claims

1. A method for constructing an underground deep foundation pit for a circulating water pump room, characterized in that: The following steps are involved: a. Measure and lay out the lines on the ground where the deep foundation pit is to be dug according to the drawings, and use excavators and crushers to dig the guide wall trenches for the ground-connected walls surrounding the foundation pit; b. After the guide wall groove is dug, tie the guide wall steel mesh along the groove wall of the guide wall groove; c. After the guide wall steel mesh is tied, the guide wall formwork for pouring the guide wall is set up; d. After the guide wall formwork is set up, pour concrete into the guide wall formwork; e. After the concrete solidifies, remove the guide wall formwork; f. Use bentonite to make mud, expand for more than 24 hours and backfill the bentonite mud into the guide wall groove after passing the test; g. Use trenching machines to dig trenches for pouring ground-connected walls; h. Use a truck crane to hoist the steel cage into the trench of the ground-connected wall; i. Then, a truck crane is used to insert a concrete conduit into the trench of the ground-connected wall. The concrete conduit is inserted into the steel cage located in the trench of the ground-connected wall; j. After the concrete conduit is installed, pour concrete into the ground-connected wall groove through the concrete conduit; k. According to steps g~j, pour all the ground-connected walls surrounding the foundation pit and wait for the concrete of the ground-connected walls to solidify; 1. After the concrete of the ground-connected wall solidifies, a pit of the foundation pit is excavated in the area enclosed by the ground-connected wall, so that the wall surface of the ground-connected wall on one side of the pit is exposed and used as the outer formwork for pouring the foundation pit wall; m. The pit of the foundation pit is excavated in sections in the vertical direction. For each section of the pit, a horizontal H-shaped steel is set on the wall surface of each ground-connected wall exposed in the pit. The H-shaped steels on the ground-connected walls arranged opposite to each other are located at the same horizontal position, and the H-shaped steels on the ground-connected walls arranged opposite to each other have different heights. One of the vertical plates of the H-shaped steel is fixed on the wall surface of the ground-connected wall to form an upper support groove opening upward at the upper end of the H-shaped steel and a lower limit groove opening downward at the lower end. A cross bracing beam is provided between the other vertical plate of the H-shaped steel and the vertical plate on the outer side of the opposite H-shaped steel; n. After the pit of the foundation pit is dug, the H-shaped steel and the cross bracing beam are laid out, the bottom surface of the pit of the foundation pit is poured; o. After the concrete at the bottom of the pit is solidified, install a steel cage of the pit wall between the lowest H-shaped steel and the bottom of the pit, so that the upper end of the steel cage is stuck in the lower limit groove of the lowest H-shaped steel; p. Then, the inner formwork of the foundation pit wall on one side of the pit, on which the steel cage section is installed in the previous step, is supported, and a concrete pouring opening is opened at the upper end of the inner formwork; q. pouring the foundation pit wall located at the template section through the concrete pouring port on the inner template; r. Install the steel cage of the pit wall of the adjacent section above the section where the casting is completed, so that the lower end of the steel cage of this section is stuck in the upper support groove of the H-shaped steel below the section, and the upper end is stuck in the lower limit groove of the H-shaped steel above the section, and then support the inner formwork of the pit wall of this section, and pour concrete into this section through the concrete pouring port of the inner formwork; s. Repeat step r until the entire foundation pit wall is poured. After the concrete solidifies, remove the outer formwork of all the foundation pit walls on one side of the pit, and the pouring of the underground foundation pit of the pump house is completed.

2. The method for constructing a deep underground foundation pit for a circulating water pump room according to claim 1 is characterized in that: The H-shaped steel is fixed on the wall surface of the ground-connected wall by screws.

3. The method for constructing a deep underground foundation pit for a circulating water pump room according to claim 1, characterized in that: There are four cross bracing beams between each pair of H-shaped steels arranged opposite to each other, and the four cross bracing beams are evenly arranged along the length direction of the H-shaped steels.

4. A pit wall formwork support structure for an underground deep foundation pit of a circulating water pump room, characterized in that: The inner wall surface of the ground-connected wall located outside the foundation pit and surrounding the foundation pit is used as the outer template of the foundation pit wall. On the inner wall surface of each ground-connected wall, a number of H-shaped steels are fixed at intervals in the up-down direction. Each of the H-shaped steels is horizontally arranged, and the side vertical plate on one side thereof is in contact with the inner wall surface of the ground-connected wall, so as to form an upper support groove opening upward at the upper end of the H-shaped steel and a lower limit groove at the lower end; the number of the H-shaped steels on the opposite ground-connected walls is equal, and the arrangement is symmetrical, and the H-shaped steels on the two opposite ground-connected walls are located at the same height. A horizontal bracing beam is supported between the side vertical plates on the outer sides of the two H-shaped steels, and the H-shaped steels on the non-opposite ground-connected walls are set at different heights; the inner lining steel cage of each pit wall of the foundation pit is divided into several pieces, which are installed above and below the H-shaped steel on the ground-connected wall, and the upper end of each steel cage is embedded in the lower limit groove of the H-shaped steel on the corresponding side, and the lower end is embedded in the upper support groove of the H-shaped steel on the corresponding side; the inner side template of the foundation pit wall is set to fit the plate surface of the vertical plate on the other side of the H-shaped steel supporting the horizontal bracing beam, and a concrete pouring port is opened on the inner side template; The H-shaped steel is fixed to the wall surface of the ground-connected wall by screws; There are four cross bracing beams between each pair of H-shaped steels arranged opposite to each other, and the four cross bracing beams are evenly arranged in the length direction of the H-shaped steels.

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