Novel anti-seismic steel structure vestibule

Abstract

The utility model discloses a novel anti-seismic steel structure vestibule which comprises a vestibule steel support and a steel truss vestibule structure erected on the top of the vestibule steel support, and the top of one side of the vestibule steel support is flexibly connected with the bottom of one side of the steel truss vestibule structure through a rolling support. The top of the other side of the vestibule steel support is rigidly connected with the bottom of the other side of the steel truss vestibule structure, and the moving direction of the rolling support is kept consistent with the length direction of the steel truss vestibule structure. The vestibule structure has the advantages of being light in self weight, large in span, small in occupied area, high in industrialization degree, high in anti-seismic performance and short in construction period.

Description

Technical Field

[0001] This utility model relates to the field of industrial building technology, specifically to a novel earthquake-resistant steel structure corridor. Background Technology

[0002] In recent years, with the rapid development of my country's industry, it has become difficult to ensure the continuity of large-scale production by transporting materials by truck in factories, and the transportation costs are high. Continuous transport belts and hoses can not only ensure sufficient material supply and are inexpensive, but also enable automated control. This has led to the widespread application of steel structure corridors that support mechanized equipment such as belts and hoses in enterprises such as metallurgy, mining, coal, power generation, cement, and ports.

[0003] However, the traditional steel structure corridors currently in widespread use mostly employ reinforced concrete supports to support the brick-concrete corridor body, which has many drawbacks:

[0004] 1) Heavy weight: The high density of reinforced concrete and brick-concrete materials makes the corridor extremely heavy. This poses a greater challenge to infrastructure construction, requiring more building materials to enhance the foundation's load-bearing capacity and increasing construction costs. Furthermore, the excessive weight generates greater seismic forces during earthquakes, which is extremely detrimental to the building's seismic performance and increases the risk of structural damage during earthquakes.

[0005] 2) Small span: Due to constraints on structural strength and stability, traditional corridors generally have small spans. In some industrial settings that require traversing large spaces, traditional corridors are insufficient. If their use is to be forced, additional supporting structures must be added, which not only increases construction costs but also occupies more land resources, making the factory layout even more cramped.

[0006] 3) Large footprint: The traditional structure of corridors necessitates a large foundation support area to ensure structural stability. Furthermore, sufficient space must be reserved around the corridor to prevent it from interfering with other buildings. In today's environment of increasingly scarce land resources and soaring land prices, this undoubtedly significantly increases land costs for businesses and limits their development potential.

[0007] 4) Low level of industrialization: Most of the construction work of traditional corridors needs to be completed on site. The construction process involves a variety of complex procedures, such as concrete pouring and wall construction. The construction process is cumbersome and labor-intensive.

[0008] 5) Poor seismic performance: In earthquake-prone areas, traditional corridors are unable to withstand the impact of earthquakes. When an earthquake occurs, their structure is easily damaged, which may lead to the collapse of the corridor. This will not only interrupt the transportation of materials and affect the production of enterprises, but also threaten the lives and property of personnel on site.

[0009] 6) Long construction period: From the foundation construction to the construction of the corridor body and then to the installation and commissioning of equipment, the construction process of traditional corridors is lengthy and requires a long wait before they can be put into operation, making it impossible to respond quickly to market demands. Utility Model Content

[0010] In order to overcome the problems of traditional steel structure corridors, such as heavy weight, small span, large footprint, low degree of industrialization, poor seismic performance, and long construction period, this utility model provides a new type of seismic-resistant steel structure corridor.

[0011] The technical solution of this utility model is as follows:

[0012] A novel earthquake-resistant steel structure corridor is characterized by comprising a corridor steel support and a steel truss corridor structure erected on top of the corridor steel support. The top of one side of the corridor steel support is flexibly connected to the bottom of one side of the steel truss corridor structure via a rolling support, and the top of the other side of the corridor steel support is rigidly connected to the bottom of the other side of the steel truss corridor structure. The movement direction of the rolling support is consistent with the length direction of the steel truss corridor structure.

[0013] As a preferred embodiment of this utility model, the steel support frame of the corridor is connected to the ground concrete foundation through embedded parts.

[0014] As a preferred embodiment of this utility model, the rolling support includes a rolling part and a fixed part disposed below the rolling part. The rolling part can move horizontally relative to the fixed part. The top of one side of the corridor steel support is connected to the fixed part, and the bottom of one side of the steel truss corridor structure is connected to the rolling part.

[0015] As a preferred embodiment of the present invention, the rolling part includes a motion roller, a mounting top seat and a pair of first hanging ears disposed at the bottom of the mounting top seat. The motion roller is provided with roller shafts on both sides, which are respectively passed through the pair of first hanging ears. The first hanging ears are provided with first elongated limiting holes for the roller shafts to pass through. The opening direction of the first elongated limiting holes is consistent with the length direction of the steel truss corridor structure.

[0016] The fixing part includes a mounting base and a pair of second hanging ears disposed on the top of the mounting base. The second hanging ears are provided with second elongated limiting holes for the roller shaft to pass through. The opening direction of the second elongated limiting holes is consistent with the length direction of the steel truss corridor structure.

[0017] The motion roller abuts between the mounting top and the mounting base and is capable of rolling in the horizontal direction to create a displacement difference between the mounting top and the mounting base in the horizontal direction.

[0018] As a preferred embodiment of this utility model, the steel truss corridor structure is composed of an upper steel beam support frame, a lower steel beam support frame, and two side steel trusses spliced ​​together.

[0019] As a preferred embodiment of this utility model, the two sides of the upper steel beam support frame are connected to the top of the two side steel trusses by bolts, and the two sides of the lower steel beam support frame are respectively connected to the bottom of the two side steel trusses by bolts.

[0020] As a preferred embodiment of this utility model, the upper steel beam support frame includes multiple upper main beams spaced apart side by side along the length direction of the steel truss corridor structure, and an upper horizontal support member is provided between two adjacent upper main beams.

[0021] As a preferred embodiment of this utility model, the lower steel beam support frame includes multiple lower main beams spaced apart side by side along the length direction of the steel truss corridor structure, and a lower horizontal support member and multiple secondary beams spaced apart side by side are provided between two adjacent lower main beams.

[0022] As a preferred embodiment of this utility model, the corridor steel support includes a first corridor steel support and a second corridor steel support arranged opposite to each other. The top of the first corridor steel support is flexibly connected to the bottom of one side of the steel truss corridor structure through the rolling support, and the top of the second corridor steel support is rigidly connected to the bottom of the other side of the steel truss corridor structure.

[0023] As a preferred embodiment of this utility model, the top of the first corridor steel support is provided with two first mounting seats arranged opposite to each other, and the two first mounting seats are flexibly connected to the left and right ends of the bottom side of the steel truss corridor structure through the rolling support.

[0024] The top of the second corridor steel support is provided with two second mounting seats arranged opposite each other, and the two second mounting seats are rigidly connected to the bottom left and right ends of the other side of the steel truss corridor structure.

[0025] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0026] 1. By setting rolling supports on one side of the steel truss corridor structure and flexibly connecting them with the corridor steel support, the horizontal displacement of the corridor steel support and the steel truss corridor structure can be released, enabling the corridor structure to better adapt to horizontal forces and avoid structural damage due to restricted horizontal displacement. This greatly improves the corridor structure's ability to withstand horizontal loads and resist earthquakes, ensuring production safety and the safety of people's lives and property in earthquake-prone areas.

[0027] 2. The use of steel support and steel truss corridor structure instead of traditional reinforced concrete support and brick-concrete structure corridor body not only reduces the footprint, but also significantly reduces the weight of the entire corridor structure, thereby reducing the difficulty and cost of infrastructure construction and shortening the construction period.

[0028] 3. It breaks through the limitations of traditional structures in terms of span. The span of the corridor structure can generally reach about 30m, and when the belt lifting height increases, the span can even reach more than 50m. The larger span reduces the setting of supporting structures, which reduces construction costs and land area, and also provides greater flexibility for the layout of the corridor. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a schematic diagram of the structure of a novel earthquake-resistant steel structure corridor in one embodiment of the present invention;

[0031] Figure 2 for Figure 1 Enlarged view of section A;

[0032] Figure 3 for Figure 1 Enlarged view of section B;

[0033] Figure 4 for Figure 1 Enlarged view of section C;

[0034] Figure 5 This is an exploded view of the rolling support in one embodiment of the present invention;

[0035] In the diagram,

[0036] 1. Corridor steel support frame; 11. First corridor steel support frame; 111. First mounting base; 12. Second corridor steel support frame; 121. Second mounting base; 2. Steel truss corridor structure; 21. Upper steel beam support frame; 211. Upper main beam; 212. Upper horizontal support; 22. Lower steel beam support frame; 221. Lower main beam; 222. Lower horizontal support; 223. Secondary beam; 23. Side steel truss; 24. Purlin; 3. Rolling support; 31. Rolling part; 311. Moving roller; 3111. Roller shaft; 312. Mounting top seat; 313. First hanging ear; 3131. First long strip limiting hole; 32. Fixing part; 321. Mounting base; 322. Second hanging ear; 3221. Second long strip limiting hole. Detailed Implementation

[0037] To make the technical problem to be solved, the technical solution, and the beneficial effects of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be noted that similar reference numerals and letters in the following drawings indicate similar items; therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. It is also declared that the embodiments described below are only for explaining this utility model and are not intended to limit this utility model.

[0038] It should be noted that the terms "installation," "setting," "connection," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly defined. Indications of orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used in the application's product, or the orientation or positional relationship commonly understood by those skilled in the art, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. The terms "first" and "second" are used only for descriptive purposes and should not be construed as indicating or implying relative importance or implying a number of technical features. "A plurality" means two or more, unless otherwise explicitly defined.

[0039] Please see Figures 1 to 4This embodiment provides a novel earthquake-resistant steel structure corridor, including a corridor steel support 1 and a steel truss corridor structure 2 erected on top of the corridor steel support 1. The corridor steel support 1 is connected to the ground concrete foundation through embedded parts. The steel truss corridor structure 2 is assembled from an upper steel beam support frame 21, a lower steel beam support frame 22, and two side steel trusses 23. The top of one side of the corridor steel support 1 is flexibly connected to the bottom of one side of the steel truss corridor structure 2 through a rolling support 3, and the top of the other side of the corridor steel support 1 is rigidly connected to the bottom of the other side of the steel truss corridor structure 2. The movement direction of the rolling support 3 is consistent with the length direction of the steel truss corridor structure 2. The rolling support 3 includes a rolling part 31 and a fixed part 32 disposed below the rolling part 31. The rolling part 31 can move horizontally relative to the fixed part 32. The top of one side of the corridor steel support 1 is connected to the fixed part 32, and the bottom of one side of the steel truss corridor structure 2 is connected to the rolling part 31.

[0040] This invention, by flexibly connecting a rolling support 3 to the steel truss corridor structure 1 on one side of the steel truss corridor structure 2, enables the release of horizontal displacement of both the steel truss corridor structure 1 and the steel truss corridor structure 2. When encountering horizontal loads such as earthquakes, the rolling part 31 of the rolling support 3 can move horizontally relative to the fixed part 32, allowing the corridor structure to better adapt to horizontal forces and avoid structural damage due to restricted horizontal displacement. This significantly improves the corridor structure's ability to withstand horizontal loads and its earthquake resistance, ensuring production safety and the safety of life and property in earthquake-prone areas. Using the corridor steel support 1 and the steel truss corridor structure 2 instead of the traditional reinforced concrete support and brick-concrete structure not only reduces the footprint but also significantly lightens the weight of the entire corridor structure, thereby reducing the difficulty and cost of foundation construction. Breaking through the limitations of traditional structures in terms of span, the span of the corridor structure can generally reach about 30m, and when the belt lifting height increases, the span can even reach more than 50m; the larger span reduces the setting of supporting structures, which reduces construction costs and land area, and also provides greater flexibility for the layout of the corridor.

[0041] The corridor structure of this utility model can be installed by factory manufacturing and on-site assembly, which has a high degree of industrialization. Compared with the traditional method of carrying out most of the construction work on-site, it reduces the complex on-site construction procedures, reduces labor intensity, and is more conducive to ensuring construction quality. During installation, there is no need to occupy a large amount of on-site construction space or to erect ground-mounted disc-lock scaffolding, which not only reduces the safety risks during the erection process but also eliminates the erection link, thereby effectively improving work efficiency. At the same time, it shortens the construction cycle, reduces labor and equipment rental costs, and significantly reduces construction costs.

[0042] In one embodiment, the top of one side of the corridor steel support 1 is connected to the fixing part 32 by bolts, and the bottom of one side of the steel truss corridor structure 2 is connected to the rolling part 31 by bolts. Using bolts to connect the fixing part 32 of the corridor steel support 1 and the rolling part 31 of the rolling support 3, and the steel truss corridor structure 1 and the rolling part 31 of the rolling support 3, is relatively simple to operate. Construction personnel can complete the installation and disassembly work using conventional tools such as wrenches. During the installation phase, compared with welding and other connection methods, it eliminates the need for complex welding equipment and professional welding skills, reducing construction difficulty and improving installation efficiency. In later maintenance, repair, or replacement of parts, if a part of the rolling support 3, the corridor steel support 1, or the steel truss corridor structure 2 is damaged, it can be easily replaced by removing the bolts, reducing maintenance time and costs.

[0043] Please see Figure 5 In one embodiment, the rolling part 31 includes a moving roller 311, a mounting top 312, and a pair of first lugs 313 disposed at the bottom of the mounting top 312. The moving roller 311 has roller shafts 3111 respectively passing through the pair of first lugs 313 on both sides. Each first lug 313 has a first elongated limiting hole 3131 through which the roller shaft 3111 passes. The opening direction of the first elongated limiting hole 3131 is consistent with the length direction of the steel truss corridor structure 2. The fixing part 32 includes a mounting base 321 and a pair of second lugs 322 disposed at the top of the mounting base 321. Each second lug 322 has a second elongated limiting hole 3221 through which the roller shaft 3111 passes. The opening direction of the second elongated limiting hole 3221 is consistent with the length direction of the steel truss corridor structure 2. The motion roller 311 abuts between the mounting top seat 312 and the mounting base 321 and is able to roll in the horizontal direction to form a displacement difference between the mounting top seat 312 and the mounting base 321 in the horizontal direction.

[0044] In one embodiment, the upper steel beam support frame 21 is bolted to the top of the two side steel trusses 23 on both sides, and the lower steel beam support frame 22 is bolted to the bottom of the two side steel trusses 23 on both sides. The bolted connections facilitate the assembly of the various parts of the steel truss corridor structure 2, enabling rapid installation and disassembly during construction. If any part is damaged or needs replacement, the process can be carried out efficiently. Simultaneously, the bolted connections ensure the stability of the structural connections, effectively preventing relative displacement between components when transferring loads. This ensures that the entire steel truss corridor structure 2 works collaboratively under the loads from material transportation and natural environmental loads, maintaining the overall strength and stability of the structure.

[0045] Of course, in other embodiments, the two sides of the upper steel beam support frame 21 can also be connected to the top of the two side steel trusses 23 by welding or other means, and the two sides of the lower steel beam support frame 22 can also be connected to the bottom of the two side steel trusses 23 by welding or other means. This utility model does not limit this.

[0046] Please see Figure 4 In one embodiment, the upper steel beam support frame 21 includes multiple upper main beams 211 spaced side-by-side along the length of the steel truss corridor structure 2, with upper horizontal support members 212 provided between adjacent upper main beams 211. The upper main beams 211, as the main load-bearing components, can bear the weight of the material transport equipment above and the materials themselves. The side-by-side spacing design makes the load distribution more uniform, improving the structure's load-bearing capacity. The upper horizontal support members 212 enhance the overall stability of the upper steel beam support frame 21, effectively preventing the upper main beams 211 from shifting or deforming in the horizontal direction and resisting the effects of horizontal forces such as wind loads.

[0047] Please see Figure 4 In one embodiment, the lower steel beam support frame 22 includes multiple lower main beams 221 spaced parallel to each other along the length of the steel truss corridor structure 2. A lower horizontal support member 222 and multiple secondary beams 223 spaced parallel to each other are arranged between adjacent lower main beams 221. The lower main beams 221 and the upper main beams 211 together form a vertical load-bearing system, bearing the vertical load of the entire corridor structure. Their parallel and spaced arrangement helps to evenly distribute the load and improve load-bearing efficiency. The lower horizontal support member 222, the lower main beams 221, and the secondary beams 223 cooperate with each other to enhance the lateral force resistance of the lower steel beam support frame 22, ensuring that the structure will not undergo excessive deformation or damage when subjected to horizontal forces. The secondary beams 223 increase the local load-bearing capacity of the structure, better adapting to the layout requirements of equipment inside the corridor, and work in conjunction with the upper steel beam support frame 21 to maintain the overall stability of the steel truss corridor structure 2.

[0048] Please see Figure 1In one embodiment, the corridor steel support 1 includes a first corridor steel support 11 and a second corridor steel support 12 arranged opposite to each other. The top of the first corridor steel support 11 is flexibly connected to the bottom of one side of the steel truss corridor structure 2 through a rolling support 3, and the top of the second corridor steel support 12 is rigidly connected to the bottom of the other side of the steel truss corridor structure 2. This combination of rigid and flexible connection effectively solves the displacement problem of the corridor structure under the action of factors such as pedestrian traffic, vehicle movement, and earthquakes. The rigid connection ensures reliable force transmission between the corridor steel support 1 and the steel truss corridor structure 2, ensuring the stability of the structure under normal use; while the flexible connection of the rolling support 3 allows the steel truss corridor structure 2 to have a certain displacement in the horizontal direction, avoiding excessive horizontal loads on the corridor structure and greatly improving the adaptability and safety of the corridor structure.

[0049] Please see Figure 2 , Figure 3 In one embodiment, the top of the first corridor steel support 11 is provided with two first mounting seats 111 arranged opposite each other, and the two first mounting seats 111 are flexibly connected to the left and right ends of the bottom side of one side of the steel truss corridor structure 2 through rolling supports 3; the top of the second corridor steel support 12 is provided with two second mounting seats 121 arranged opposite each other, and the two second mounting seats 121 are rigidly connected to the left and right ends of the bottom side of the other side of the steel truss corridor structure 2. The two first mounting seats 111 on the first corridor steel support 11 cooperate with the rolling supports 3 to make the horizontal displacement of the steel truss corridor structure 2 smoother and more stable, reducing structural deformation caused by uneven displacement. The second mounting seats 121 on the second corridor steel support 12 rigidly connect the steel truss corridor structure 2, enhancing the reliability of the structural connection parts, ensuring the strength and stability of the structural connection parts under vertical loads and partial horizontal loads, and ensuring that the entire corridor structure can operate safely and reliably under various working conditions.

[0050] Please see Figure 1 , Figure 4In one embodiment, multiple arrayed purlins 24 are provided on the top of the upper steel beam support frame 21, the bottom of the lower steel beam support frame 22, and the outer sides of the two side steel trusses 23. These arrayed purlins 24 provide convenient connection points for the subsequent installation of other components. The arrayed layout design allows installers to flexibly select appropriate locations for installing reinforcing steel bars and other components according to actual needs, eliminating the need to determine installation locations and methods on-site, reducing uncertainty and complexity during installation, and thus improving installation efficiency. Since the corridor structure may require different types and numbers of reinforcing components under different usage scenarios and working conditions, the arrayed distribution of the purlins 24 allows for adaptation to these changes. Whether adding more reinforcing steel bars to improve structural strength or installing other functional components, these pre-set purlins 24 can be quickly adapted, enhancing the versatility and scalability of the corridor structure.

[0051] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

[0052] The present utility model patent has been described above with reference to the accompanying drawings. Obviously, the implementation of the present utility model patent is not limited to the above-described manner. Any improvements made by adopting the inventive concept and technical solution of the present utility model patent, or the direct application of the inventive concept and technical solution of the present utility model patent to other occasions without modification, are all within the protection scope of the present utility model.

Claims

1. A new type of earthquake resistant steel structure veranda, characterized in that, The corridor steel support and the steel truss corridor structure erected on the top of the corridor steel support are connected, one side of the top of the corridor steel support is connected with one side of the bottom of the steel truss corridor structure through a rolling support, the other side of the top of the corridor steel support is rigidly connected with the other side of the bottom of the steel truss corridor structure, and the movement direction of the rolling support is consistent with the length direction of the steel truss corridor structure.

2. The new earthquake resistant steel structure porch according to claim 1, characterized in that, The corridor steel support is connected with the ground concrete foundation through a pre-embedded part.

3. The new earthquake resistant steel structure porch according to claim 1, characterized in that, The rolling support comprises a rolling part and a fixed part arranged below the rolling part, the rolling part can move in the horizontal direction relative to the fixed part, one side of the top of the corridor steel support is connected with the fixed part, and one side of the bottom of the steel truss corridor structure is connected with the rolling part.

4. The new earthquake resistant steel structure porch according to claim 3, characterized in that, The rolling part comprises a moving roller, a mounting top seat and a pair of first hanging ears arranged at the bottom of the mounting top seat, roller shafts are arranged on the two sides of the moving roller and respectively pass through the pair of first hanging ears, first long strip limiting holes are formed in the first hanging ears and the roller shafts pass through the first long strip limiting holes, and the opening direction of the first long strip limiting holes is consistent with the length direction of the steel truss corridor structure. The fixed part comprises a mounting base and a pair of second hanging ears arranged at the top of the mounting base, second long strip limiting holes are formed in the second hanging ears and the roller shafts pass through the second long strip limiting holes, and the opening direction of the second long strip limiting holes is consistent with the length direction of the steel truss corridor structure. The moving roller is arranged between the mounting top seat and the mounting base and can roll in the horizontal direction to form the displacement difference between the mounting top seat and the mounting base in the horizontal direction.

5. The new earthquake resistant steel structure porch according to claim 1, characterized in that, The steel truss corridor structure is formed by an upper steel beam support frame, a lower steel beam support frame and two side steel truss splices.

6. The new earthquake resistant steel structure porch according to claim 5, characterized in that, The two sides of the upper steel beam support frame are connected with the top of the two side steel trusses through bolts, and the two sides of the lower steel beam support frame are respectively connected with the bottom of the two side steel trusses through bolts.

7. The new earthquake resistant steel structure porch according to claim 5, characterized in that, The upper steel beam support frame comprises a plurality of upper main beams which are arranged in parallel and spaced apart along the length direction of the steel truss corridor structure, and an upper horizontal support is arranged between two adjacent upper main beams.

8. The new earthquake resistant steel structure porch according to claim 5, characterized in that, The lower steel beam support frame comprises a plurality of lower main beams which are arranged in parallel and spaced apart along the length direction of the steel truss corridor structure, a lower horizontal support and a plurality of lower secondary beams which are arranged in parallel and spaced apart are arranged between two adjacent lower main beams.

9. The new earthquake resistant steel structure porch according to claim 1, characterized in that, The corridor steel support comprises a first corridor steel support and a second corridor steel support which are arranged oppositely, the top of the first corridor steel support is flexibly connected with one side of the bottom of the steel truss corridor structure through the rolling support, and the top of the second corridor steel support is rigidly connected with the other side of the bottom of the steel truss corridor structure.

10. The new earthquake resistant steel structure porch according to claim 9, characterized in that, The top of the first corridor steel support is provided with two first mounting seats which are arranged oppositely left and right, and the two first mounting seats are respectively flexibly connected with the left and right ends of one side of the bottom of the steel truss corridor structure through the rolling support. The top of the second corridor steel support is provided with two second mounting seats which are arranged oppositely left and right, and the two second mounting seats are respectively rigidly connected with the left and right ends of the other side of the bottom of the steel truss corridor structure.

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