Construction method of a storage tank

Abstract

This invention discloses a construction method for a water storage tank, comprising: S1, excavating a foundation pit; S2, setting up a bottom trench; S2a, laying a bottom impermeable layer; S3, arranging prefabricated assembly support modules and assembling them into an internal support body; S3a, laying a top impermeable layer and connecting it with the bottom impermeable layer to cover the internal support body; S4, sealing the top slab, so that the bottom trench and the top slab enclose the internal support body, and the support modules support the top slab. This method combines prefabricated modules with a cast-in-place top slab to form a composite construction system: the modules are assembled into a support body, which serves as a non-removable support, eliminating the need for full-scale scaffolding erection and dismantling, and also as a permanent structure that shares the load with the top slab; the impermeable layer covers and forms a sealed water storage space. This method combines the convenience of PP modules with the load-bearing capacity of concrete, and has significant advantages in construction speed, structural stress, safety, and cost.

Description

Technical Field

[0001] This invention relates to the field of regulating reservoir construction technology, and specifically to a regulating reservoir construction method. Background Technology

[0002] Rainwater storage tanks are key facilities in industrial plants and municipal infrastructure for realizing the utilization of rainwater resources, preventing urban flooding, and meeting environmental protection requirements. Their core functions are to reduce peak emissions, reduce pipeline pressure, and utilize rainwater resources.

[0003] Existing water storage tank structures mainly employ two schemes: PP modular prefabricated tanks and reinforced concrete cast-in-place tanks. PP modular tanks form a supporting framework by assembling standardized polypropylene perforated modules, which are then wrapped with an impermeable membrane. Construction is fast and installation is easy, but the overall load-bearing capacity of the modules is generally low, and the overall integrity is poor. Under heavy loads or large overburden loads, the structural stability and long-term durability are insufficient, easily leading to roadbed settlement. Reinforced concrete cast-in-place tanks are constructed by excavating, binding reinforcement on-site, setting up formwork, and pouring concrete as a whole to form a rigid structure. They have strong load-bearing capacity, excellent integrity and durability, and can meet the requirements of deep burial and heavy loads. However, their construction defects are prominent: the erection and curing of the internal full-span support frame leads to a long construction period; the formwork work in the limited space of the deep foundation pit is extensive, posing a high safety risk; and pipeline construction often occurs at the end of the project, with excessively long construction periods severely restricting the overall progress.

[0004] Therefore, to solve the above problems, a construction method for regulating reservoirs is needed that can simultaneously meet the requirements of rapid and convenient construction and excellent stress system. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to overcome the defects in the prior art and provide a method for constructing a regulating reservoir that can simultaneously meet the requirements of rapid and convenient construction and excellent stress system.

[0006] The construction method for the regulating storage tank of the present invention includes the following construction steps:

[0007] S1. Excavation of the foundation pit;

[0008] S2. Set up a regulating tank bottom trench inside the foundation pit;

[0009] S2a. Lay a bottom impermeable layer in the bottom trench of the storage tank;

[0010] S3. Prefabricated assembly support modules are arranged in the bottom trench of the storage tank. The prefabricated assembly support modules consist of several blocks, and the several prefabricated assembly support modules are assembled to form an internal support body.

[0011] S3a. Lay the top impermeable layer and connect the top impermeable layer with the bottom impermeable layer so that the two cover the internal support.

[0012] S4. Cover the top of the storage tank bottom trough with the storage tank top plate, so that the storage tank bottom trough and the storage tank top plate enclose the internal support body in a preset space, and the prefabricated support module supports the storage tank top plate.

[0013] Furthermore, the prefabricated assembly support module is any type of assembleable polypropylene module in the prior art, with corresponding positioning and connection structures on the top, bottom, left, right, front, and back, so that a number of polypropylene modules can form a stable internal support after assembly. Preferably, the internal porosity of the polypropylene module is not less than 90%.

[0014] Furthermore, when arranging the prefabricated assembly support module in step S3, the pipeline extending out of the bottom trench of the storage tank is pre-embedded simultaneously.

[0015] The pipeline includes an upstream sewage inlet channel and a downstream venting channel, both of which are connected to the interior of the regulating tank bottom trough.

[0016] Furthermore, the sewage inlet channel has a sewage inlet connecting to the preset environment I, and a sewage discharge device is arranged inside the sewage inlet channel. The sewage discharge device is used to discharge the sewage in the sewage inlet channel to the preset environment II.

[0017] The drainage channel is equipped with a discharge device, which is used to discharge the water stored in the storage tank to the preset environment III.

[0018] Furthermore, between steps S3 and S4, step S3b is also included: filling a lateral protective layer between the internal support and the side wall of the storage tank bottom trough.

[0019] Furthermore, before sealing the top slab of the storage tank in step S4, a top protective layer is laid above the top impermeable layer. The top protective layer and the side protective layer are continuous. Both the side protective layer and the top protective layer are sand bodies, which are filled or laid in preset positions during use.

[0020] Furthermore, the bottom trough of the storage tank includes an integrally cast bottom slab and side slabs, with top reinforcing bars pre-reserved at the top of the side slabs.

[0021] Furthermore, the top reinforcing bar extends upward and is higher than the designed top surface of the storage tank top slab;

[0022] The top slab of the storage tank includes nodal steel bars connected to the top steel bars, and pre-embedded steel bars that connect the nodal steel bars to form a pre-set steel bar skeleton.

[0023] The top slab of the storage tank is cast in place, and the cast-in-place top slab covers the top steel bars, node steel bars and pre-embedded steel bars, so that the top slab of the storage tank and the bottom tank of the storage tank form an integral whole.

[0024] Furthermore, the top edge of the side plate is basically flush with the top edge of the internal support.

[0025] Furthermore, the side plate is cast in two stages. The height of the first casting is equivalent to the preset layer height of the prefabricated assembly support module; the second casting is carried out simultaneously with the top plate of the storage tank in step S4.

[0026] Furthermore, the internal support body formed by assembling several of the prefabricated assembly support modules will fill the preset space.

[0027] Furthermore, both the bottom impermeable layer and the top impermeable layer include an intermediate impermeable membrane and geotextiles respectively disposed on both sides of the impermeable membrane.

[0028] The beneficial effects of this invention are as follows: This invention discloses a construction method for a water storage tank, which organically combines prefabricated assembled support modules with a cast-in-place reinforced concrete roof slab to form a novel composite water storage tank construction system. Its core concept lies in: utilizing prefabricated assembled support modules to quickly assemble an internal support structure. On one hand, this serves as a non-removable support system for the roof slab pouring during construction, eliminating the need for traditional full-span scaffolding erection and dismantling; on the other hand, it acts as a permanent structure, working in tandem with the cast-in-place roof slab to evenly transfer the roof load to the base slab through the internal support structure. Furthermore, the impermeable layer completely covers the internal support structure, forming a sealed water storage space. This construction method integrates the convenience of PP module construction with the load-bearing capacity of reinforced concrete structures, achieving an excellent balance between construction speed, load-bearing performance, safety, and overall cost. Attached Figure Description

[0029] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0030] Figure 1 This is a schematic diagram of the structure of the present invention.

[0031] Reference numerals: 1-bottom plate; 2-side plate; 3-bedding layer; 4-bottom impermeable layer; 5-prefabricated assembled support module; 6-sewage inlet channel; 7-drainage channel; 8-lateral protective layer; 9-top impermeable layer; 10-regulating tank top plate; 11-top protective layer; 12-sewage discharge equipment; 13-discharge equipment. Detailed Implementation

[0032] Figure 1 As shown in the figure, the construction method of the regulating reservoir in this embodiment includes the following construction steps:

[0033] S1. Excavate the foundation pit at the pre-designated site. As the construction site for the regulating reservoir, this step is the same as conventional construction. A water interception ditch is set at the top of the foundation pit slope, and a drainage ditch and a collection well are set at the bottom of the slope to promptly pump out accumulated water and prevent surface water from seeping into the foundation pit.

[0034] S2. A regulating tank bottom trench is constructed within the foundation pit; the regulating tank bottom trench comprises an integrally cast bottom slab 1 and side slabs 2, avoiding construction joints between the bottom slab 1 and side slabs 2, thus eliminating the common leakage channel of horizontal construction joints from the structural body, and improving the self-waterproofing and load-bearing capacity of the regulating tank bottom trench. Of course, the bottom slab 1 and side slabs 2 can also be constructed separately, which will not be elaborated here.

[0035] During construction, a concrete foundation layer 3 is first poured on the base, with a smooth and firm surface. Reinforcing bars for the bottom slab 1 are then tied onto the foundation layer 3, and high-strength concrete blocks are used to ensure the thickness of the protective layer. The upper reinforcing mesh is supported by stirrups. Subsequently, pre-reserved reinforcing bars for the side slabs 2 are arranged, and side formwork is erected. The entire process is then completed by integrally pouring reinforced concrete to form the bottom trench of the storage tank. The top of the side slabs 2 has pre-reserved upward-extending reinforcing bars for subsequent connection to the top slab.

[0036] S2a. Lay the bottom impermeable layer 4 in the bottom trench of the storage tank; remove the laitance, oil, and dust from the inner surface of the bottom plate 1 and side plate 2, fill the air holes and sand holes with cement mortar, and round the inside and outside corners to prevent stress concentration and cracking of the impermeable layer at right angles. Keep the laying loose and leave a 3% to 5% expansion allowance, and lay from the bottom to the top. Wrap the sharp corners with waste geotextile for protection.

[0037] S3. Prefabricated assembly support modules 5 are arranged in the bottom trough of the storage tank. The prefabricated assembly support modules 5 consist of several blocks, and the prefabricated assembly support modules 5 are assembled to form an internal support body.

[0038] In this embodiment, the prefabricated assembly support module 5 is any type of assembleable polypropylene module in the prior art, with corresponding positioning and connection structures on the top, bottom, left, right, front, and back, so that several polypropylene modules can form a stable internal support after assembly. Preferably, the internal porosity of the polypropylene module is not less than 90%. While providing sufficient vertical support force, it hardly occupies the effective water storage space of the regulating reservoir, and the product is mature, has excellent performance, can be directly purchased and assembled, and has low operating costs.

[0039] In this embodiment, when arranging the prefabricated assembly support module 5 in this step, pipelines extending out of the bottom trench of the storage tank are simultaneously pre-embedded. These pipelines include an upstream sewage inlet channel 6 and a downstream drainage channel 7, both of which are connected to the interior of the storage tank bottom trench. Pre-embedding the pipelines during the module assembly stage avoids damage to the impermeable layer and the overall structure caused by later drilling, ensuring the sealing quality at the junction of the pipeline and the impermeable layer, and eliminating potential leakage risks at the source. The cross-sectional dimensions of the pre-embedded pipelines are approximately the same as those of a single prefabricated assembly support module 5, allowing for complete embedding into the internal support structure, making implementation more convenient. The sewage inlet channel 6 and the drainage channel 7 also serve as maintenance channels, expanding their functionality.

[0040] In this embodiment, the internal support body formed by assembling several prefabricated assembly support modules 5 fills the preset space, minimizes the proportion of ineffective space, maximizes the effective water storage volume of the regulating reservoir, and provides a reliable support structure.

[0041] S3b. A lateral protective layer 8 is filled between the internal support and the side wall of the storage tank bottom. The lateral protective layer 8 is filled between the internal support and the side wall to form a lateral constraint on the internal support, limiting its lateral deformation and displacement during concrete pouring and long-term use, and ensuring that the internal support maintains a stable geometric shape and stress state during construction and use.

[0042] S3a. Lay the top impermeable layer 9 and connect the top impermeable layer 9 with the bottom impermeable layer 4 so that the two cover the internal support and protect the internal support.

[0043] In this embodiment, before sealing the top slab 10 of the storage tank in step S4, a top protective layer 11 is laid above the top impermeable layer 9. The top protective layer 11 and the lateral protective layer 8 are continuous. The continuous arrangement of the top protective layer 11 and the lateral protective layer 8 forms a continuous and uninterrupted buffer barrier on the outer side of the entire impermeable layer, eliminating weak points at the joints of the protective layer and avoiding the risk of local exposure of the impermeable membrane due to discontinuity of the protective layer. The top protective layer 11 also provides a protective cushion layer for subsequent top slab construction, preventing damage to the impermeable membrane during steel reinforcement binding and concrete pouring. Both the lateral protective layer 8 and the top protective layer 11 are made of sand. They are laid symmetrically in layers from both sides towards the center, and each layer is compacted. Using sand as the protective layer utilizes the roundness and fluidity of sand particles to tightly fill the irregular gaps between the internal support and the sidewalls; the symmetrical layered filling method avoids the eccentric force generated by unilateral filling, which could cause the internal support to tilt or shift; and the layered compaction ensures the density and overall stability of the protective layer.

[0044] S4. The top plate 10 of the storage tank is sealed on the top of the storage tank bottom trough, so that the storage tank bottom trough and the storage tank top plate 10 enclose the internal support body in a preset space, and the prefabricated assembly support module 5 supports the storage tank top plate 10.

[0045] In this embodiment, the top of the side plate 2 is pre-reserved with top reinforcing bars. These top reinforcing bars extend upwards and are higher than the designed top surface of the storage tank top plate 10, ensuring sufficient anchorage length within the top plate. The storage tank top plate 10 includes node reinforcing bars connected to the top reinforcing bars, as well as embedded reinforcing bars that connect the node reinforcing bars to form a pre-designed reinforcing bar skeleton. The storage tank top plate 10 is cast-in-place, and the cast-in-place storage tank top plate 10 covers the top reinforcing bars, node reinforcing bars, and embedded reinforcing bars, making the storage tank top plate 10 and the storage tank bottom trough an integral whole. The node reinforcing bars and embedded reinforcing bars constitute a complete reinforcing bar skeleton. After being covered together with the cast-in-place concrete, the connection between the storage tank top plate 10 and the storage tank bottom trough changes from a simple lap joint to a rigid node where the reinforcing bars and concrete work together to bear the load. The overall integrity and seismic performance are significantly better than traditional construction joint connection methods.

[0046] In this embodiment, the top edge of the side plate 2 and the top edge of the internal support are basically flush, so that the bottom surface of the storage tank top plate 10 can simultaneously adhere to the top surface of the side plate 2 and the top surface of the internal support when it is poured, thus avoiding the appearance of steps or suspended areas on the bottom surface of the storage tank top plate 10 and ensuring the continuity and uniformity of the force on the storage tank top plate 10.

[0047] In this embodiment, the side plate 2 is cast in two stages. The height of the first casting is equivalent to the preset floor height of the prefabricated assembly support module 5. The second casting is carried out simultaneously with the top plate 10 of the storage tank in step S4, so that the upper part of the side plate 2 and the top plate form a seamless whole, and the shear bearing capacity and overall stiffness of the node are significantly improved.

[0048] During construction, node reinforcement bars connected to the pre-reserved top reinforcement bars on the top of the side plate 2 are tied above the top protective layer 11, and pre-embedded reinforcement bars are used to connect the node reinforcement bars to form a pre-designed reinforcement skeleton. The top reinforcement bars extend upwards and are higher than the designed top surface of the storage tank top plate 10 to ensure sufficient anchorage length. The second pouring of the side plate 2 is carried out simultaneously with the storage tank top plate 10, forming a tank top structure with an upward-facing groove. Continuous pouring and compaction are performed using an immersion vibrator. The cast-in-place storage tank top plate 10 covers the top reinforcement bars, node reinforcement bars, and pre-embedded reinforcement bars, making the storage tank top plate 10 and the storage tank bottom trench an integral whole. The top surface of the internal support is completely attached to the bottom surface of the storage tank top plate 10, forming a composite load-bearing system. This step also includes the formwork erection process for the top side wall before pouring and the formwork removal work before curing after pouring.

[0049] After sealing the top slab of the storage tank in step S4, the top slab is cured. The internal support structure is retained as a permanent structure and is exempt from dismantling, completely eliminating the time consumption, labor costs, and safety risks associated with traditional full-span scaffolding dismantling procedures. This construction method uses less concrete and requires less formwork, greatly shortening the construction period while ensuring the functionality of the storage tank.

[0050] The core concept of this construction method lies in the rapid assembly of prefabricated modular support modules 5 to form an internal support structure. This serves two purposes: firstly, it provides a non-removable support system for the pouring of the roof slab during construction, eliminating the need for traditional full-span scaffolding erection and dismantling; secondly, it acts as a permanent structure, working in tandem with the cast-in-place roof slab to evenly transfer the roof load to the base slab 1; simultaneously, the impermeable layer completely encloses the internal support structure, creating a sealed water storage space. This method integrates the convenience of PP module construction with the load-bearing capacity of reinforced concrete structures, achieving an excellent balance between construction speed, load-bearing performance, safety, and overall cost.

[0051] In this embodiment, the sewage inlet channel 6 has a sewage inlet connecting to a preset environment I. A sewage discharge device 12 is arranged within the sewage inlet channel 6, which discharges sewage from the sewage inlet channel 6 to a preset environment II. An outlet device 13 is installed within the drainage channel 7, which discharges water stored in the storage tank to a preset environment III. The sewage discharge device 12 and outlet device 13 are located upstream and downstream respectively, undertaking the functions of intercepting sewage before storage and discharging water after storage. This achieves full-process functional integration of water intake, sewage interception, water storage, and drainage of the storage tank, enabling the storage tank to not only have water volume regulation capabilities but also water quality control capabilities. The sewage discharge equipment 12 is any sewage pump of the existing technology, and the discharge equipment 13 is any air venting pump of the existing technology. The preset environment I is the drainage ditch or sewage outlet of the external environment, etc. The preset environment II and the preset environment III can be the same downstream rainwater well or different. The preset environment II is the sewage pipe network or sewage collection pool well, etc., and the preset environment III is the rainwater pipe network or rainwater collection pool, etc. The layout is arranged according to the construction site and usage requirements, which will not be elaborated here.

[0052] In this embodiment, both the bottom impermeable layer 4 and the top impermeable layer 9 include a middle impermeable membrane and geotextiles respectively disposed on both sides of the impermeable membrane. A geotextile is disposed on each side of the impermeable membrane; the inner geotextile protects the impermeable membrane from puncture and abrasion by the five edges of the prefabricated assembled support module, while the outer geotextile protects the impermeable membrane from damage by sharp particles in the backfill material. This double-layer geotextile sandwich impermeable membrane structure provides dual protection for the impermeable layer's puncture resistance and service life.

[0053] This embodiment organically combines the prefabricated assembled support module 5 with the cast-in-place reinforced concrete roof slab using the aforementioned construction method. The internal support structure serves both as a non-removable support system during construction, completely eliminating the traditional full-span scaffolding erection and dismantling process and shortening on-site work time, and as a permanent structure fully integrated with the roof slab, forming a composite load-bearing system that combines ease of construction with high load-bearing capacity, meeting the requirements of deep-buried heavy-load conditions. During construction, the amount of formwork work required by personnel in the limited space of the deep foundation pit is reduced, effectively lowering safety risks. The impermeable layer completely covers the internal support structure, and the protective layer provides all-round buffering for the impermeable layer. Pre-embedded pipelines integrate the inlet and outlet functions of the storage tank. The support module has a high porosity, occupying very little of the effective internal volume of the storage tank, and the water storage function is not affected. This construction method significantly shortens the construction period, reduces safety risks, reduces the amount of steel reinforcement and concrete used, saves machinery and labor costs, resulting in significant economic benefits, while ensuring excellent load-bearing performance and water storage effect.

[0054] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for constructing a regulating reservoir, characterized in that: The construction steps include the following: S1. Excavation of the foundation pit; S2. Set up a regulating tank bottom trench inside the foundation pit; S2a. Lay a bottom impermeable layer in the bottom trench of the storage tank; S3. Prefabricated assembly support modules are arranged in the bottom trench of the storage tank. The prefabricated assembly support modules consist of several blocks, and the several prefabricated assembly support modules are assembled to form an internal support body. S3a. Lay the top impermeable layer and connect the top impermeable layer with the bottom impermeable layer so that the two cover the internal support. S4. Cover the top of the storage tank bottom trough with the storage tank top plate, so that the storage tank bottom trough and the storage tank top plate enclose the internal support body in a preset space, and the prefabricated support module supports the storage tank top plate.

2. The method for constructing a regulating reservoir according to claim 1, characterized in that: When arranging the prefabricated assembly support module in step S3, the pipeline extending out of the bottom trench of the storage tank is pre-embedded simultaneously. The pipeline includes an upstream sewage inlet channel and a downstream venting channel, both of which are connected to the interior of the regulating tank bottom trough.

3. The method for constructing a regulating reservoir according to claim 2, characterized in that: The sewage inlet channel has a sewage inlet that connects to the preset environment I. A sewage discharge device is arranged inside the sewage inlet channel, which is used to discharge the sewage in the sewage inlet channel to the preset environment II. The drainage channel is equipped with a discharge device, which is used to discharge the water stored in the storage tank to the preset environment III.

4. The method for constructing a regulating reservoir according to claim 1, characterized in that: Between steps S3 and S4, there is also step S3b: filling a lateral protective layer between the internal support and the side wall of the storage tank bottom trough.

5. The method for constructing a regulating reservoir according to claim 4, characterized in that: Before sealing the top plate of the storage tank in step S4, a top protective layer is laid above the top impermeable layer, and the top protective layer and the side protective layer are continuous.

6. The method for constructing a regulating reservoir according to claim 1, characterized in that: The storage tank bottom trough includes an integrally cast bottom slab and side slabs, with top reinforcement bars pre-installed at the top of the side slabs.

7. The method for constructing a regulating reservoir according to claim 6, characterized in that: The top reinforcing bar extends upward and is higher than the designed top surface of the storage tank top slab; The top slab of the storage tank includes nodal steel bars connected to the top steel bars, and pre-embedded steel bars that connect the nodal steel bars to form a pre-set steel bar skeleton. The top slab of the storage tank is cast in place, and the cast-in-place top slab covers the top steel bars, node steel bars and pre-embedded steel bars, so that the top slab of the storage tank and the bottom tank of the storage tank form an integral whole.

8. The method for constructing a regulating reservoir according to claim 6, characterized in that: The top edge of the side plate is basically flush with the top edge of the internal support.

9. The method for constructing a regulating reservoir according to claim 1, characterized in that: The internal support body formed by assembling several of the prefabricated assembly support modules will fill the preset space.

10. The method for constructing a regulating reservoir according to claim 1, characterized in that: Both the bottom impermeable layer and the top impermeable layer include an intermediate impermeable membrane and geotextiles respectively disposed on both sides of the impermeable membrane.

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