An ultra-deep underground storage structure and a method of constructing the same

Abstract

The application provides a reasonable design of an ultra-deep underground storage structure and a construction method thereof, and solves a series of problems such as construction safety and feasibility, structural stress deformation, waterproofing, moisture-proofing, anti-floating stability and the like of the ultra-deep underground storage structure. The initial lining of the upper structure is a caisson; the initial lining of the lower structure mainly comprises vertical grouting steel pipes, prestressed anchor cables, a system of engaged waist beams and an initial lining concrete layer; the upper ends of the vertical grouting steel pipes extend into blade foot gaps, the blade foot gaps are filled with cement layers, and the cement layers are integrated with the reinforced layers; the concrete lining of the upper structure is fixed on the inner wall of the caisson, and a waterproof layer is laid between the inner wall of the caisson and the concrete lining; the concrete lining of the lower structure is fixed on the initial lining concrete layer, and a waterproof layer is laid between the initial lining concrete layer and the concrete lining; the upper end of the lock mouth ring beam is connected with the concrete lining of the upper structure, and the lower end of the lock mouth ring beam is connected with the concrete lining of the lower structure; and a waterproof layer is laid between the caisson and the lock mouth ring beam.

Description

Technical Field

[0001] This invention relates to an ultra-deep underground storage structure and its construction method. Background Technology

[0002] Ultra-deep underground storage structures are characterized by their small footprint and great depth. Currently, there are two methods for their construction: one is to first construct the storage structure after the foundation pit is excavated and supported. However, as the excavation depth increases, the risk of the foundation pit rises significantly. To ensure safety, the support strength needs to be strengthened, increasing project costs and construction time. The other method is to sink the main structure underground using caissons. The caissons serve as both the foundation pit support system and the main load-bearing system. However, as the sinking depth increases, or in hard rock strata, the frictional resistance on the outside of the caisson is high, making sinking difficult. Furthermore, it is impossible to construct a waterproof layer around the caisson, resulting in poor waterproofing performance. In addition, the construction of ultra-deep underground storage structures also faces the challenge of buoyancy control, which is currently generally addressed only through counterweights. Summary of the Invention

[0003] The purpose of this invention is to overcome the above-mentioned shortcomings in the prior art and to provide a reasonably designed ultra-deep underground storage structure and its construction method.

[0004] The technical solution adopted by this invention to solve the above problems is: an ultra-deep underground storage structure, wherein the storage structure is divided into an upper structure and a lower structure; characterized in that: the upper structure is located in the soil layer, the initial lining of the upper structure is a caisson, and the lower end of the caisson is provided with a cutting edge structure, the cutting edge structure including an inner cutting edge and an outer cutting edge, both the inner and outer cutting edges are fixedly set at the lower end of the caisson, the inner and outer cutting edges are arranged in an inward and outward manner, and a cutting edge gap is provided between the inner and outer cutting edges; the lower structure is located in the rock layer, and the initial lining of the lower structure is mainly composed of vertical grouting steel pipes, prestressed anchor cables, interlocking waist beam system and initial lining concrete layer; the vertical grouting steel pipes inject grout into the surrounding rock fissures to form a reinforcement layer; the upper end of the vertical grouting steel pipes extends into the cutting edge gap, the cutting edge gap is filled with a cement layer, the cement layer is integrated with the reinforcement layer; the interlocking waist beam system includes The structure comprises a steel lattice waist beam, anchor blocks, and anchor rods. Anchor blocks are embedded in the reinforcement layer, with steel beams pre-embedded within them. The steel lattice waist beam is integrated with the steel beams within the reinforcement layer. Anchor rods and prestressed anchor cables are fixed within the anchor blocks. A primary lining concrete layer is fixed to the inner wall of the reinforcement layer and is also fixed to the anchor blocks. Both the upper and lower structures use concrete linings. The concrete lining of the upper structure is fixed to the inner wall of the caisson, with a waterproof layer laid between the inner wall of the caisson and the concrete lining. The concrete lining of the lower structure is fixed to the primary lining concrete layer, with a waterproof layer laid between the primary lining concrete layer and the concrete lining. A locking ring beam is installed at the lower end of the caisson, with its upper end connected to the concrete lining of the upper structure and its lower end connected to the concrete lining of the lower structure. A waterproof layer is laid between the caisson and the locking ring beam.

[0005] The cutting edge structure of the present invention also includes a cutting edge platform, which is fixedly installed at the lower end of the caisson, and the inner cutting edge is fixed on the cutting edge platform; a hole is provided on the cutting edge platform, and the hole is connected to the gap between the cutting edge and the cutting edge.

[0006] The present invention has steel bar splicing sleeves pre-embedded in the upper and lower ends of the lock ring beam. The steel bar splicing sleeve at the upper end of the lock ring beam is connected to the pre-embedded steel bars in the concrete lining of the upper structure, and the steel bar splicing sleeve at the lower end of the lock ring beam is connected to the pre-embedded steel bars in the concrete lining of the lower structure.

[0007] The anchor block of the present invention has a square planar shape and a trapezoidal side shape.

[0008] The anchor block of the present invention has a shear-resistant fender block protruding into the rock mass on the upper middle part of the soil-facing side.

[0009] The anchor block of the present invention has a reserved anchor cable channel and a reserved anchor sealing groove on its back side; the prestressed anchor cable and anchor rod pass through the anchor cable channel and are sealed in the anchor sealing groove, and then the anchor sealing groove is filled with cement.

[0010] The caisson of the present invention has pre-reserved grooves evenly opened on its inner wall and a protruding capping beam provided on its top.

[0011] The anchor rods of this invention are set at an angle upwards, and the prestressed anchor cables are set at an angle downwards.

[0012] A method for constructing an ultra-deep underground storage structure, characterized by the following steps:

[0013] 1) First, construct vertical grouting steel pipes to the predetermined elevation, and then inject grout into the surrounding rock fissures through the vertical grouting steel pipes to form a reinforcement layer and reinforce the strata;

[0014] 2) The caisson is lowered in sections until the designed depth is reached. After the bottom section of the caisson is in place, the upper end of the vertical grouting steel pipe extends into the gap between the cutting edges.

[0015] 3) Inject cement grout into the gap between the cutting edges to form a cement layer. The cement layer is integrated with the reinforcement layer, thus sealing the caisson and the rock mass reinforced by the vertical grouting steel pipe.

[0016] 4) Lay a waterproof layer at the location where the lock ring beam is set at the lower end of the caisson, and then construct the lock ring beam;

[0017] 5) After the construction of the lock ring beam is completed, the lower structure is constructed in sections. After each section of the rock mass is excavated, the vertical prestressed anchor cable and interlocking waist beam system are constructed immediately, and then concrete is sprayed into the inner wall of the reinforcement layer to form the initial lining concrete layer.

[0018] 6) After the initial lining of each section of the substructure is completed, a waterproof layer shall be laid immediately, and the surrounding rock pressure and deformation shall be monitored in real time. Based on the monitoring data, the secondary lining structure within the excavation range of this section shall be constructed in a timely manner using the reverse method.

[0019] 7) Repeat steps 5) and 6) until the construction reaches the design elevation, then promptly pour the sealing layer;

[0020] 8) During the construction of the lower structure, the waterproof layer and secondary lining structure of the upper caisson shall be constructed simultaneously. The secondary lining of the upper structure shall be connected to the bottom lock ring beam as a whole.

[0021] The present invention further includes step 9) after step 8): constructing equipment rooms and internal partition layers inside the storage structure.

[0022] Compared with the prior art, the present invention has the following advantages and effects:

[0023] 1. The structure adopts a three-layer waterproof system: the first layer consists of the upper and lower primary linings, which are sealed into a whole by pouring cement into the gap between the two cutting edges; the second layer consists of the secondary lining and the waterproof layer laid between the two linings; the third layer consists of the upper and lower secondary linings, which are connected into a whole by a lock ring beam.

[0024] 2. The anti-buoyancy system of the structure consists of three parts: the self-weight of the primary and secondary lining structures, the pull-out resistance provided by the prestressed anchor cables, and the frictional resistance between the primary lining and the stratum. The caisson and the interlocking waist beam system can fully interlock with the secondary lining structure, effectively transmitting vertical forces. When groundwater head acts on the structure, the remaining buoyancy force after deducting its self-weight is: partly transmitted to the prestressed anchor cables through the interlocking waist beam system, and then to the depths of the rock strata; another part is transmitted to the caisson wall through the interlocking action of the secondary lining and the caisson, and finally shared by the frictional resistance between the caisson wall and the stratum.

[0025] 3. This invention employs different lining types based on the varying geological properties within the ultra-deep structural depth range, and proposes a series of detailed node construction methods. This effectively connects the upper and lower structural types into a unified whole, systematically solving a series of problems related to the construction safety and feasibility of ultra-deep underground storage structures, structural stress and deformation, waterproofing and moisture prevention, and buoyancy stability. This invention is particularly suitable for situations where bedrock exists below a certain burial depth in ultra-deep storage structures. The invention has a sound theoretical basis, facilitates mechanized construction, is safe and economical, and is not limited to industrial or civil underground storage fields, making its future application value extremely high. Attached Figure Description

[0026] Figure 1 This is a cross-sectional structural diagram of an embodiment of the present invention.

[0027] Figure 2 for Figure 1 A magnified structural diagram of point A in the middle.

[0028] Figure 3 This is a schematic diagram of the planar structure of the lower end of the caisson in an embodiment of the present invention.

[0029] Figure 4 for Figure 3 Schematic diagram of the cross-sectional structure of BB.

[0030] Figure 5 This is a schematic diagram of the structure of the lock ring beam according to an embodiment of the present invention.

[0031] Figure 6 For Figure 1 A magnified structural diagram at point C.

[0032] Figure 7 This is a partial planar cross-sectional view of the lower structure in an embodiment of the present invention.

[0033] Figure 8 This is a side view of the interlocking waist beam system according to an embodiment of the present invention.

[0034] Figure 9-1 and Figure 9-2These are all schematic diagrams of the force transmission path of the anchor block in embodiments of the present invention.

[0035] Figure 10 This is a construction process diagram of an embodiment of the present invention. Detailed Implementation

[0036] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. The following embodiments are explanations of the present invention, but the present invention is not limited to the following embodiments.

[0037] The storage structure of this invention is divided into an upper structure and a lower structure. The overall construction method is a primary lining + waterproof layer + secondary lining. However, different lining types are used depending on the different geological conditions of the upper and lower parts.

[0038] The superstructure is located within the soil layer. The initial lining of the superstructure is a caisson 1, which sinks easily in the soil and avoids the risk of large deformation of the soil foundation pit. A cutting edge structure is provided at the lower end of the caisson 1. The cutting edge structure includes an inner cutting edge 41, an outer cutting edge 42, and a cutting edge platform 43. The outer cutting edge 42 and the cutting edge platform 43 are both fixedly installed at the lower end of the caisson 1, while the inner cutting edge 41 is fixed to the cutting edge platform 43. Thus, the inner cutting edge 41 is positioned at the lower end of the caisson 1, with the inner and outer cutting edges 41 and 42 arranged in an inward-outward configuration, and a cutting edge gap is provided between them. Holes 5 are provided on the cutting edge platform 43, communicating with the cutting edge gap, and can serve as excavation and grouting ports during construction.

[0039] The lower structure is located within the rock strata. Due to the strong self-stabilizing ability of the rock strata, the initial lining of the lower structure mainly consists of vertical grouting steel pipes 6, prestressed anchor cables 10, interlocking waist beam system 11, and an initial lining concrete layer 12. The vertical grouting steel pipes 6 inject grout into the surrounding rock fissures to form a reinforcement layer 22; the upper end of the vertical grouting steel pipes 6 extends into the cutting edge gap. The cutting edge gap is filled with a cement layer 7, which is integrated with the reinforcement layer 22. The cement layer 7 serves three purposes: first, it seals the gap between the upper and lower initial linings, making the sealed initial lining act as the first water-stopping system; second, it hardens the soil between the vertical grouting steel pipes 6 and the cutting edge, enabling the transmission of horizontal reaction forces and supporting the vertical grouting steel pipes 6; and third, it acts as an internal horizontal brace for the well wall, enhancing the stability of the structure.

[0040] The interlocking groin system 11 enables the secondary lining and primary lining of the substructure to interlock, effectively transferring vertical forces and ensuring that the entire structure can share the load and work together. The interlocking groin system 11 includes a steel lattice groin beam 14, anchor blocks 15, and anchor rods 16. Anchor blocks 15 are installed in the reinforcement layer 22, and steel beams 17 are pre-embedded within the anchor blocks 15, extending a certain length beyond the anchor blocks 15. The steel lattice groin beam 14 is installed in the reinforcement layer 22, and the steel lattice groin beam 14 and the steel beam 17 are spliced ​​together to form a whole.

[0041] Both the anchor rod 16 and the prestressed anchor cable 10 are fixed in the anchor block 15. The anchor rod 16 is set obliquely upward, and the prestressed anchor cable 10 is set obliquely downward. The anchor block 15 has a square plane and a trapezoidal side. A shear-resistant tenon block 18 protruding into the rock mass is set on the upper middle part of its soil-facing side to keep it stable vertically. An anchor cable channel is reserved in the anchor block 15, and a sealing groove 19 is reserved on its soil-facing side. After the prestressed anchor cable 10 and the anchor rod 16 pass through the anchor cable channel and are sealed in the sealing groove 19, the sealing groove 19 is filled with cement. The thickness of the anchor block 15 is greater than the thickness of the primary lining concrete layer 12. The purpose is that after the primary lining concrete layer 12 and the waterproof layer 13 are laid, the anchor block 15 can still penetrate into the secondary lining and interlock with it, thereby transmitting vertical force. The primary lining concrete layer 12 is fixed on the inner wall of the reinforcement layer 22, and the primary lining concrete layer 12 is fixed to the anchor block 15.

[0042] Both the superstructure and substructure secondary linings utilize cast-in-place concrete linings 2. Different construction procedures are employed depending on the rigidity of the primary lining and the geological strata: the superstructure secondary lining is constructed using a forward construction method, while the substructure secondary lining is constructed using a reverse construction method based on real-time monitoring of surrounding rock deformation. The superstructure concrete lining 2 is fixed to the inner wall of the caisson 1. Pre-reserved grooves 20 are evenly spaced on the inner wall of the caisson 1, with a protruding capping beam 21 at the top, ensuring a stronger connection between the caisson 1 and the concrete lining 2. A waterproof layer 13 is laid between the inner wall of the caisson 1 and the concrete lining 2. The pre-reserved grooves 20 are trapezoidal, ensuring both sufficient interlocking with the secondary lining concrete and a tight fit between the waterproof layer 13 and it. The substructure concrete lining 2 is fixed to the primary lining concrete layer 12, with a waterproof layer 13 laid between the primary lining concrete layer 12 and the concrete lining 2.

[0043] The specific transmission path of anchor block 15 is shown in the figure. Figure 9-1 and Figure 9-2 During construction, the weight transfer F of the secondary lining G To the upper surface of anchor block 15, F G The tension F1 provided by the anchor bolt 16, the shear-resistant fender 18 subjected to the vertical shear force V1, and the supporting force F2 provided by the rock mass below the anchor block 15 are jointly borne by the anchor bolt 16; while during the normal service life, the secondary lining is subjected to the upward buoyancy force F. N The force transmitted to the lower surface of the anchor block 15 is jointly borne by the tension F3 in the direction of the prestressed anchor cable 10, the shear force V2 in the vertical direction of the shear-resistant falcon block 18, and the support force F4 provided by the rock mass above the anchor block 15.

[0044] A locking ring beam 8 is installed at the lower end of the caisson 1. The upper end of the locking ring beam 8 connects to the concrete lining 2 of the upper structure, and the lower end connects to the concrete lining 2 of the lower structure. Reinforcing steel splice sleeves 9 are pre-embedded at both ends of the locking ring beam 8. The reinforcing steel splice sleeve 9 at the upper end of the locking ring beam 8 connects to the pre-embedded reinforcing steel in the concrete lining 2 of the upper structure, and the reinforcing steel splice sleeve 9 at the lower end of the locking ring beam 8 connects to the pre-embedded reinforcing steel in the concrete lining 2 of the lower structure. A waterproof layer 13 is laid between the caisson 1 and the locking ring beam 8. The locking ring beam 8 serves three purposes: first, it bears part of the self-weight when the secondary lining of the lower structure is constructed using a reverse method; second, it connects the secondary lining of the upper and lower structures into a whole so that they share the load and effectively transfer vertical forces; and third, it forms a closed system with the secondary lining, acting as a third layer of waterproofing.

[0045] The cross-sectional shape of the storage structure is not limited to circular or rectangular. The vertical section is wider at the top and narrower at the bottom. The equipment auxiliary room 3 can be arranged within the area of ​​the upper structure. The remaining internal space is open from top to bottom, which is more conducive to mechanized layout. The specific division is determined according to the specific function of the storage structure.

[0046] as follows Figure 10 As shown, a method for constructing an ultra-deep underground storage structure includes the following steps:

[0047] 1) First, construct 6 vertical grouting steel pipe piles to the predetermined elevation, and then grout into the surrounding rock fissures through the 6 vertical grouting steel pipes to form a reinforcement layer 22, thereby reinforcing the stratum;

[0048] 2) The caisson 1 is lowered in sections until the designed depth is reached. After the bottom section of the caisson 1 is in place, the upper end of the vertical grouting steel pipe 6 extends into the gap between the cutting edges.

[0049] 3) Cement grout is injected into the gap between the cutting edges through the hole 5 to form a cement layer 7. The cement layer 7 is connected with the reinforcement layer 22 to seal the caisson 1 and the rock mass reinforced by the vertical grouting steel pipe 6, completely isolating the external groundwater from the interior of the structure, serving as the first waterproofing system.

[0050] 4) A waterproof layer 13 is laid at the location where the lock ring beam 8 is set at the lower end of the caisson 1, and then the lock ring beam 8 is constructed to prepare for the subsequent construction of the lower structure using the reverse construction method.

[0051] 5) After the construction of the lock ring beam 8 is completed, the lower structure is constructed in sections. After each section of the rock mass is excavated, the vertical prestressed anchor cable 10 and the interlocking waist beam system 11 are immediately constructed. Then, concrete is sprayed onto the inner wall of the reinforcement layer 22 to form the initial lining concrete layer 12.

[0052] 6) After the initial lining of each section of the substructure is completed, the waterproof layer 13 shall be laid immediately, and the surrounding rock pressure and deformation shall be monitored in real time. Based on the monitoring data, the secondary lining structure within the excavation range of this section shall be constructed in a timely manner using the reverse method.

[0053] 7) Repeat steps 5)-6) until the construction reaches the design elevation, then promptly pour the sealing layer; then lay the waterproof layer 13 of the structural base slab and construct the structural base slab;

[0054] 8) During the construction of the lower structure, the waterproof layer 13 and the secondary lining structure of the upper caisson 1 shall be constructed simultaneously. The secondary lining of the upper structure shall be connected to the bottom lock ring beam 8 as a whole.

[0055] 9) Construction of equipment rooms and internal partition layers inside the construction storage structure. At this point, the main part of the ultra-deep underground storage structure is completed. While ensuring structural safety and stability, it can effectively prevent seepage, water damage, and buoyancy.

[0056] Furthermore, it should be noted that the specific embodiments described in this specification may differ in the shape and name of their components, etc. The above description is merely illustrative of the structure of the present invention. All equivalent or simple variations made based on the structure, features, and principles described in this patent concept are included within the protection scope of this patent. Those skilled in the art can make various modifications or additions to the described specific embodiments or use similar methods to substitute them, as long as they do not deviate from the structure of the present invention or exceed the scope defined by the claims, all of which should fall within the protection scope of this invention.

Claims

1. An ultra-deep underground storage structure, wherein the storage structure is divided into an upper structure and a lower structure; characterized in that: The superstructure is located in the soil layer. Its initial lining is a caisson, with a cutting edge structure at the lower end. This cutting edge structure includes an inner and outer cutting edge, both fixedly positioned at the lower end of the caisson, arranged in an inward-outward configuration, with a gap between them. The substructure is located in the rock layer. Its initial lining mainly consists of vertical grouting steel pipes, prestressed anchor cables, an interlocking girder system, and an initial lining concrete layer. The vertical grouting steel pipes inject grout into the surrounding rock fissures to form a reinforcement layer. The upper end of the vertical grouting steel pipes extends into the cutting edge gap, which is filled with a cement layer, integrated with the reinforcement layer. The interlocking girder system includes steel lattice girders, anchor blocks, and anchor rods. The anchor blocks are located within the reinforcement layer. Steel beams are pre-embedded in the caisson; steel lattice waist beams are set in the reinforcement layer, and the steel lattice waist beams are spliced ​​with the steel beams to form a whole; anchor bolts and prestressed anchor cables are all fixed in the anchor blocks; a primary lining concrete layer is fixed on the inner wall of the reinforcement layer, and the primary lining concrete layer is fixed to the anchor blocks; the secondary linings of both the upper and lower structures are made of concrete; the concrete lining of the upper structure is fixed to the inner wall of the caisson, and a waterproof layer is laid between the inner wall of the caisson and the concrete lining; the concrete lining of the lower structure is fixed on the primary lining concrete layer, and a waterproof layer is laid between the primary lining concrete layer and the concrete lining; a lock ring beam is set at the lower end of the caisson, the upper end of the lock ring beam is connected to the concrete lining of the upper structure, and the lower end is connected to the concrete lining of the lower structure; a waterproof layer is laid between the caisson and the lock ring beam.

2. The ultra-deep underground storage structure according to claim 1, characterized in that: The cutting edge structure also includes a cutting edge platform, which is fixedly installed at the lower end of the caisson, and the inner cutting edge is fixed on the cutting edge platform; holes are provided on the cutting edge platform, and the holes are connected to the gaps between the cutting edges.

3. The ultra-deep underground storage structure according to claim 1, characterized in that: Rebar splicing sleeves are pre-embedded in the upper and lower ends of the lock-type ring beam. The rebar splicing sleeve at the upper end of the lock-type ring beam is connected to the pre-embedded rebar in the concrete lining of the upper structure, and the rebar splicing sleeve at the lower end of the lock-type ring beam is connected to the pre-embedded rebar in the concrete lining of the lower structure.

4. The ultra-deep underground storage structure according to claim 1, characterized in that: The anchor block has a square planar shape and a trapezoidal side shape.

5. The ultra-deep underground storage structure according to claim 1, characterized in that: The anchor block has a shear-resistant fender block protruding into the rock mass located on the upper middle part of the soil-facing side.

6. The ultra-deep underground storage structure according to claim 1, characterized in that: The anchor block has a reserved anchor cable channel and a reserved anchor sealing groove on its back side; the prestressed anchor cable and anchor rod pass through the anchor cable channel and are sealed in the anchor sealing groove, and then the anchor sealing groove is filled with cement.

7. The ultra-deep underground storage structure according to claim 1, characterized in that: The inner wall of the caisson is uniformly provided with reserved grooves, and the top is provided with a protruding capping beam.

8. The ultra-deep underground storage structure according to claim 1, characterized in that: The anchor bolts are set at an angle upwards, and the prestressed anchor cables are set at an angle downwards.

9. A method for constructing an ultra-deep underground storage structure as described in any one of claims 1-8, characterized in that: Includes the following steps: 1) First, construct vertical grouting steel pipes to the predetermined elevation, and then inject grout into the surrounding rock fissures through the vertical grouting steel pipes to form a reinforcement layer and reinforce the strata; 2) The caisson is lowered in sections until the designed depth is reached. After the bottom section of the caisson is in place, the upper end of the vertical grouting steel pipe extends into the gap between the cutting edges. 3) Inject cement grout into the gap between the cutting edges to form a cement layer. The cement layer is integrated with the reinforcement layer, thus sealing the caisson and the rock mass reinforced by the vertical grouting steel pipe. 4) Lay a waterproof layer at the location where the lock ring beam is set at the lower end of the caisson, and then construct the lock ring beam; 5) After the construction of the lock ring beam is completed, the lower structure is constructed in sections. After each section of the rock mass is excavated, the vertical prestressed anchor cable and interlocking waist beam system are constructed immediately, and then concrete is sprayed into the inner wall of the reinforcement layer to form the initial lining concrete layer. 6) After the initial lining of each section of the substructure is completed, a waterproof layer shall be laid immediately, and the surrounding rock pressure and deformation shall be monitored in real time. Based on the monitoring data, the secondary lining structure within the excavation range of this section shall be constructed in a timely manner using the reverse method. 7) Repeat steps 5) and 6) until the construction reaches the design elevation, then promptly pour the sealing layer; 8) During the construction of the lower structure, the waterproof layer and secondary lining structure of the upper caisson shall be constructed simultaneously. The secondary lining of the upper structure shall be connected to the bottom lock ring beam as a whole.

10. The construction method according to claim 9, characterized in that: After step 8), step 9 is also included: constructing the equipment rooms and internal partition layers inside the storage structure.

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