A space truss support system

Abstract

The present invention relates to the field of building construction, specifically a space truss support system, including a space truss support structure arranged between purlins, each space truss support structure is provided with a space truss structure, adjustment parts at both ends and a prestressed device connected to the adjustment parts. The space truss structure is composed of a plurality of space truss standard units connected in sequence, and the unit includes a node, a steel support standard section, a lateral stabilizer bar, an oblique stabilizer bar, etc., and at least one layer of a tetrahedral connecting rod structure composed of a lateral stabilizer bar and an oblique stabilizer bar. The adjustment part is formed by connecting an L-shaped hanging arm with an adjustment head, and can adjust the connection between the prestressed device and the node. Compared with the prior art, the present invention reduces the calculated length of the steel support, improves the horizontal and vertical stability, reduces the deformation of the self-weight internal force, and can be freely combined to adapt to various foundation pits. The node universal connector has strong adaptability, providing an efficient and reliable support solution for underground structure construction and foundation pit safety.

Description

Technical Field

[0001] The invention relates to the technical field of building construction, and in particular to a space truss support system. Background Art

[0002] In the field of modern construction engineering, especially in the construction of underground structures, ensuring the safety of the side walls of the foundation pit and the surrounding environment is a crucial link. This requirement forces the construction party to adopt effective support, reinforcement and protection measures to cope with complex geological conditions, soil pressure and various uncertain factors in the construction process.

[0003] In the construction of subways, municipal roads and other projects, narrow foundation pit construction is common. Due to the tight construction schedule and cost control pressure, the construction party usually gives priority to using steel pipe support as the main support method for open excavation foundation pits. Steel pipe support has the advantages of easy material acquisition and relatively simple installation, which can meet the basic needs of construction to a certain extent.

[0004] However, with the development of construction engineering technology and the continuous improvement of construction safety standards, the existing steel pipe support technology has exposed many serious defects. The stable bearing capacity of a single support is relatively limited, and it is easy to become unstable when facing large lateral soil pressure or other external loads. Once the steel pipe support becomes unstable, it will not only cause deformation or even collapse of the side wall of the foundation pit, but may also cause serious damage to the surrounding environment, such as the tilt of adjacent buildings and the rupture of underground pipelines, which greatly threatens the life safety of construction workers and the smooth progress of the entire project, thereby causing a series of irreversible economic losses and social impacts. Therefore, there is an urgent need for a new type of support system to overcome the shortcomings of the existing steel pipe support technology to ensure the safety and stability of underground structure construction and the surrounding environment of the foundation pit. Summary of the invention

[0005] The purpose of the present invention is to provide a space truss support system in order to overcome the defects of the above-mentioned prior art. By constructing a space truss system, the calculated length of the steel support is reduced, the horizontal and vertical stability is improved, the deformation of the self-weight internal force is reduced, and it can be freely combined to adapt to various types of foundation pits. The node universal connector has strong adaptability, providing an efficient and reliable support solution for underground structure construction and foundation pit safety.

[0006] The purpose of the present invention can be achieved by the following technical solutions:

[0007] The present invention provides a space truss support system, comprising a space truss support structure arranged between surrounding purlins;

[0008] Each of the space truss support structures comprises a space truss structure, adjustment members arranged at both ends of the space truss structure, and a prestressing device connected to the adjustment members;

[0009] One side of the prestressed device is supported on the surrounding purlin of the foundation pit;

[0010] The space truss structure comprises a plurality of space truss standard units connected in sequence, wherein the space truss standard units comprise nodes, steel support standard sections, lateral stabilizer bars, and oblique stabilizer bars, wherein the plurality of steel support standard sections are connected in sequence through the nodes, and the space truss structure is provided with at least one layer of a tetrahedral pyramid connecting rod structure formed by lateral stabilizer bars and oblique stabilizer bars;

[0011] In each layer of the tetrahedral pyramid connecting rod structure, four oblique stabilizing rods are sequentially connected to form a quadrilateral bottom structure, and the other four oblique stabilizing rods form four edges of the tetrahedral pyramid connecting rod structure;

[0012] In the quadrilateral bottom structure, two lateral stabilizer bars are arranged at a diagonal position of the quadrilateral structure to realize lateral support of the quadrilateral bottom, and one lateral stabilizer bar is perpendicular to the quadrilateral bottom structure to realize support along the height direction of the quadrangular pyramid connecting rod structure;

[0013] The adjusting member is adjustably connected between the prestressing device and the node, and is used for fine-tuning the distance between the prestressing device and the node.

[0014] The space truss standard unit also includes a connecting piece, which is used for connecting the oblique stabilizing rod and the node;

[0015] The two ends of the transverse stabilizer bar are respectively provided with an upper end plate and a lower end plate, the upper end plate is connected to a connecting plate, and the transverse stabilizer bar, the upper end plate, the lower end plate and the connecting plate are an integrated structure;

[0016] In the quadrilateral bottom structure, the lateral stabilizer bar is connected to the two oblique stabilizer bars through a connecting plate, and the lateral stabilizer bar is connected to the node through a lower end plate.

[0017] Furthermore, the node is provided with a plurality of outwardly protruding connectors, and the connectors are used for connecting the node with a transverse stabilizer bar and for connecting the node with an end plate of a connecting member.

[0018] Furthermore, the connecting piece is a cross ear plate.

[0019] Furthermore, in the quadrilateral bottom structure of the quadrangular pyramid connecting rod structure, a diagonal line of the quadrilateral bottom structure is colinear with the axial direction of the steel support standard section;

[0020] In the quadrilateral bottom structure of the quadrangular pyramid connecting rod structure, the center position of the quadrilateral bottom structure corresponds to the position of a node.

[0021] Furthermore, in the quadrilateral bottom structure of the four-sided pyramid connecting rod structure, a first oblique stabilizing rod, a second oblique stabilizing rod, a third oblique stabilizing rod, and a fourth oblique stabilizing rod are connected in sequence, respectively; the first oblique stabilizing rod and the fourth oblique stabilizing rod are respectively connected to the first node through a connecting member, the second oblique stabilizing rod and the third oblique stabilizing rod are respectively connected to the third node through a connecting member, the second node between the first node and the third node is respectively connected to the first lateral stabilizing rod, the second lateral stabilizing rod, and the third lateral stabilizing rod, and the first lateral stabilizing rod, the second lateral stabilizing rod, and the third lateral stabilizing rod constitute an inverted T-shaped support structure.

[0022] Further, among the four edges of the four-sided pyramid connecting rod structure, the fifth oblique stabilizing rod and the sixth oblique stabilizing rod respectively form a pair of edges along the length direction of the steel support standard section, and the seventh oblique stabilizing rod and the eighth oblique stabilizing rod respectively form a pair of edges along the diameter direction of the steel support standard section, and one end of the fifth oblique stabilizing rod, the sixth oblique stabilizing rod, the seventh oblique stabilizing rod, and the eighth oblique stabilizing rod are connected to each other, and the connection point is the vertex of the four-sided pyramid connecting rod structure;

[0023] The connecting plate is a cross-shaped plate structure, one end of the first lateral stabilizer bar is connected to the first oblique stabilizer bar and the second oblique stabilizer bar through the connecting plate, the second lateral stabilizer bar is connected to the third oblique stabilizer bar and the fourth oblique stabilizer bar through one end of the connecting plate, and one end of the third lateral stabilizer bar is connected to one end of the fifth oblique stabilizer bar, the sixth oblique stabilizer bar, the seventh oblique stabilizer bar, and the eighth oblique stabilizer bar through the connecting plate.

[0024] Furthermore, when the quadrangular pyramid connecting rod structure is provided with multiple layers, the quadrangular pyramid connecting rod structure of the outer layer is in an equal-proportionately enlarged relationship with the quadrangular pyramid connecting rod structure of the inner layer.

[0025] Furthermore, the adjusting member comprises an L-shaped hanging arm and an adjusting head connected to each other, one end of the L-shaped hanging arm is overlapped on the surrounding purlin, and the other end is connected to the adjusting head by bolts;

[0026] One end of the regulating head is connected to the prestressing device, and the other end is connected to the node;

[0027] The adjusting head is provided with a plurality of bolt connection positions along the axial direction, and the working condition requirements can be met by adjusting the bolt connection positions forward and backward.

[0028] Furthermore, the prestressed device is one of a jack, a prestressed steel bundle, and a prestressed anchor.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] 1) The present invention cleverly reduces the calculated length of steel supports in all directions by innovatively combining steel supports into a spatial truss structure. This design change greatly improves the stability of the steel supports in the horizontal and vertical directions. For example, in a traditional single steel support structure, due to the lack of effective lateral constraints, it is prone to lateral bending or instability when subjected to a large load. The spatial truss structure in the present invention is constructed into a stable overall spatial system by means of the interconnection between multiple steel support standard units and the four-sided pyramid structure formed by the lateral stabilizer bar, the oblique stabilizer bar and the steel support. In this system, the force can be evenly transmitted and dispersed between each unit and rod, so that the load borne by a single steel support is greatly reduced, thereby effectively enhancing the stability of the overall structure and effectively reducing the risk of foundation pit accidents caused by support instability.

[0031] 2) The unique spatial structure design of the present invention brings excellent internal force and deformation control effects. Under the action of deadweight, traditional steel support structures are prone to large internal force concentration and deformation due to their own mechanical properties. The spatial truss structure of the present invention can evenly distribute the internal force generated by the deadweight of the steel support to the entire structural system through a reasonable rod layout and connection method, thereby significantly reducing the peak value and deformation of the internal force. This advantage allows a larger span to be opened in terms of vertical support. In many foundation pit construction scenarios, it is possible to reduce or even eliminate the need to set up columns and directly place the spatial truss structure on the enclosure structure. This not only simplifies the construction process, but also completely releases the underground construction space, creating extremely favorable conditions for the entry and exit of large-scale machinery and equipment, the stacking of construction materials, and the collaborative operation of multiple types of work, greatly improving construction efficiency, shortening the construction period, and reducing construction costs.

[0032] 3) The transverse stabilizer bar of the present invention plays a key multifunctional role in the present invention. Not only can it be connected to each other to form a multi-layer tetrahedral structure to further enhance the local and overall stability, but also the transverse stabilizer bar can realize horizontal and vertical connection combinations between units. This flexible connection method enables the entire space truss support system to be freely combined according to the different layout forms and complex force requirements of various foundation pits. Whether it is a narrow and long subway foundation pit, an irregularly shaped municipal road foundation pit, or other foundation pit projects of special shapes and sizes, the space truss support system of the present invention can accurately adapt to different working conditions by adjusting the connection method and position of the transverse stabilizer bar, providing personalized support solutions for the project, showing strong versatility and adaptability, and greatly broadening its application scope in the field of construction.

[0033] 4) The present invention provides universal connectors around the nodes. This standardized connection method makes the connection between the standard units of the space truss, the lateral stabilizer bars, the diagonal stabilizer bars and other related components extremely convenient and efficient. At the construction site, construction workers do not need to perform complex customized connection operations, but can quickly complete the assembly of various components according to the standardized connection process. This not only reduces the manpower and time costs during the construction process, but also reduces the risk of quality problems caused by improper connection. At the same time, the versatility of standardized connectors makes it easier to replace and supplement components produced in different batches or at different construction stages, effectively improving the maintainability and scalability of the entire space truss support system, and further enhancing the competitiveness of the present invention in actual engineering applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 and 2 is a schematic diagram of the structure of the space truss support system in the present invention (wherein, Figure 1 is a top view, Figure 2 for the main view);

[0035] Figures 3 to 5 is a schematic diagram of the structure of the standard unit of the space truss in the present invention (wherein, Figure 3 For the main view, Figure 4 is a top view, Figure 5 is a side view);

[0036] Figure 6 It is a structural schematic diagram of the connecting member in the present invention;

[0037] Figures 7 to 9 is a schematic diagram of the structure of the adjusting member in the present invention (wherein, Figure 7 For the main view, Figure 8 is a top view, Fig. 9 is a side view);

[0038] Fig.10 and 11 is a schematic structural diagram of the multi-layer tetrahedral pyramid connecting rod structure of the present invention (wherein, Fig.10 For the main view, Fig.11 is a side view);

[0039] Fig.12 It is a schematic structural diagram of the lateral stabilizer bar in the present invention.

[0040] In the figure: 1. standard unit of space truss, 2. adjusting part, 3. prestressing device, 4. purlin, 11. node, 12. standard section of steel support, 13. connecting part, 14. transverse stabilizer bar, 15. oblique stabilizer bar, 16. upper end plate, 17. lower end plate, 18. connecting plate, 21. L-shaped hanging arm, 22. adjusting head. DETAILED DESCRIPTION

[0041] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. Component models, material names, connection structures, control methods, algorithms and other features not clearly described in this technical solution are all considered to be common technical features disclosed in the prior art.

[0042] Example 1

[0043] The space truss support system in this embodiment includes a plurality of space truss support structures arranged between the purlins 4, see Figure 1 and 2 Each of the space truss support structures comprises a space truss structure, adjustment members 2 arranged at both ends of the space truss structure, and a prestressing device 3 connected to the adjustment member 2; one side of the prestressing device 3 is supported on the surrounding purlin 4 of the foundation pit; the space truss structure comprises a plurality of space truss standard units 1 connected in sequence, see Figures 3 to 5 The space truss standard unit 1 includes a node 11, a steel support standard section 12, a connector 13, a lateral stabilizer bar 14, and an oblique stabilizer bar 15. A plurality of the steel support standard sections 12 are sequentially connected through the node 11. In the space truss structure, at least one layer of a tetrahedral pyramid connecting rod structure formed by the lateral stabilizer bar 14 and the oblique stabilizer bar 15 is provided.

[0044] In a specific implementation, in each layer of the four-sided pyramid connecting rod structure, four oblique stabilizing rods 15 are sequentially connected to form a quadrilateral bottom structure, and the other four oblique stabilizing rods 15 form four edges of the four-sided pyramid connecting rod structure;

[0045] In the quadrilateral bottom structure, two lateral stabilizer bars 14 are arranged at a diagonal position of the quadrilateral structure to achieve lateral support of the quadrilateral bottom, and one lateral stabilizer bar 14 is perpendicular to the quadrilateral bottom structure to achieve support along the height direction of the quadrangular pyramid connecting rod structure.

[0046] In a specific implementation, the adjusting member 2 is adjustably connected between the prestressing device 3 and the node 11 .

[0047] See also Figure 6 , the space truss standard unit 1 further comprises a connecting member 13, the connecting member 13 is used for connecting the oblique stabilizing rod 15 and the node 11;

[0048] The two ends of the lateral stabilizer bar 14 are respectively provided with an upper end plate 16 and a lower end plate 17, and the upper end plate 16 is connected to a connecting plate 18. The lateral stabilizer bar 14, the upper end plate 16, the lower end plate 17 and the connecting plate 18 are an integrated structure; in the quadrilateral bottom structure, the lateral stabilizer bar 14 is connected to the two oblique stabilizer bars 15 through the connecting plate 18, and the lateral stabilizer bar 14 is connected to the node 11 through the lower end plate 17.

[0049] In specific implementation, a plurality of outwardly convex connectors are provided on the node 11, and the connectors are used for connecting the node 11 with the lateral stabilizer bar 14 and connecting the node 11 with the end plate of the connector 13. The connector 13 is a cross ear plate.

[0050] In a specific implementation, in the quadrilateral bottom structure of the quadrangular pyramid connecting rod structure, a diagonal line of the quadrilateral bottom structure is collinear with the axial direction of the steel support standard section 12. In a specific implementation, optionally, in the quadrilateral bottom structure of the quadrangular pyramid connecting rod structure, the center position of the quadrilateral bottom structure corresponds to the position of a node 11.

[0051] In a specific implementation, the quadrilateral bottom structure of the quadrangular pyramid connecting rod structure is respectively composed of a first oblique stabilizing rod, a second oblique stabilizing rod, a third oblique stabilizing rod, and a fourth oblique stabilizing rod connected in sequence, and the first oblique stabilizing rod, the second oblique stabilizing rod, the third oblique stabilizing rod, and the fourth oblique stabilizing rod are respectively for Figure 4 The upper left position, the upper right position, the lower left position, and the lower right position of the middle quadrilateral bottom structure, the first oblique stabilizing rod and the fourth oblique stabilizing rod are respectively connected to the first node through the connecting member 13, and the first node corresponds to Figure 4 At the left node position, the second oblique stabilizing rod and the third oblique stabilizing rod are connected to the third node through the connecting member 13 respectively. The third node corresponds to Figure 4 The second node located between the first node and the third node is connected to the first lateral stabilizer bar, the second lateral stabilizer bar, and the third lateral stabilizer bar respectively. Figure 4 The first lateral stabilizer bar, the second lateral stabilizer bar and the third lateral stabilizer bar form an inverted T-shaped support structure. The first lateral stabilizer bar corresponds to Figure 5 The first lateral stabilizer bar corresponds to the position of the stabilizer bar on the left side in the horizontal direction, the second lateral stabilizer bar corresponds to the position of the stabilizer bar on the right side in the horizontal direction, and the third lateral stabilizer bar corresponds to the position of the stabilizer bar in the vertical direction.

[0052] In the specific implementation, among the four edges of the four-sided pyramid connecting rod structure, the fifth oblique stabilizing rod and the sixth oblique stabilizing rod respectively form a pair of edges along the length direction of the steel support standard section 12, and the fifth oblique stabilizing rod corresponds to Figure 4 The stabilizing rod position on the left side of the length direction of the steel support standard section 12, the sixth oblique stabilizing rod corresponds to the stabilizing rod position on the right side, and the seventh oblique stabilizing rod and the eighth oblique stabilizing rod form a pair of edges along the diameter direction of the steel support standard section 12, and the seventh oblique stabilizing rod corresponds to Figure 4The upper stabilizing rod position in the width direction of the middle steel support standard section 12, the eighth oblique stabilizing rod corresponds to the lower stabilizing rod position, and one ends of the fifth oblique stabilizing rod, the sixth oblique stabilizing rod, the seventh oblique stabilizing rod, and the eighth oblique stabilizing rod are connected to each other, and the connection point is the vertex of the four-sided pyramid connecting rod structure.

[0053] In specific implementation, the connecting plate 18 is a cross-shaped plate structure, one end of the first lateral stabilizer bar is connected to the first oblique stabilizer bar and the second oblique stabilizer bar through the connecting plate 18, the second lateral stabilizer bar is connected to the third oblique stabilizer bar and the fourth oblique stabilizer bar through one end of the connecting plate 18, and one end of the third lateral stabilizer bar is connected to one end of the fifth oblique stabilizer bar, the sixth oblique stabilizer bar, the seventh oblique stabilizer bar, and the eighth oblique stabilizer bar through the connecting plate 18.

[0054] In terms of technical principle, the space truss support system of the present invention is provided with one or more space truss support structures between the purlins 4 as shown in Figures 1 and 2. The core space truss support structure is composed of a space truss structure, adjustment members 2 at both ends, and a prestressing device 3 connected to the adjustment member 2. The prestressing device 3 is pressed against the purlins 4 of the foundation pit to apply prestress to enhance the overall stability. The space truss structure includes a plurality of space truss standard units 1 connected in sequence as shown in Figures 3 to 5. The node 11 in the space truss standard unit 1 connects a plurality of steel support standard sections 12 in sequence, and is provided with at least one layer of a tetrahedral connecting rod structure composed of a transverse stabilizer bar 14 and an oblique stabilizer bar 15. The oblique stabilizer bar 15 is used to construct a quadrilateral bottom structure and a tetrahedral pyramid edge. The transverse stabilizer bar 14 is distributed at a specific position at a diagonal position and perpendicular to the bottom direction of the quadrilateral to achieve support in the transverse and height directions. The adjusting member 2 is adjustably connected between the prestressing device 3 and the node 11 to facilitate adaptation to different working conditions. The space truss standard unit 1 is also provided with a connector 13 (see FIG6 ) for connecting the oblique stabilizer bar 15 with the node 11. The transverse stabilizer bar 14 has an upper end plate 16 and a lower end plate 17 at both ends and is connected with an integrated connecting plate 18, through which it is connected with the oblique stabilizer bar 15 and the node 11 in a specific manner. The convex connector on the node 11 is used to connect with the transverse stabilizer bar 14 and the end plate of the connector 13. The connector 13 is a cross-shaped ear plate. The diagonal line of the quadrilateral bottom structure of the four-sided pyramid connecting rod structure is collinear with the axis of the steel support standard section 12 and the center position can correspond to a node 11. The oblique stabilizers are connected in specific groups and connected with the transverse stabilizer bar 14 through a cross-shaped connecting plate 18, together forming a stable and reasonably stressed space truss support system, which ensures that the entire system can effectively cope with the stress conditions in the project and can be flexibly adjusted to meet the needs of different working conditions from aspects such as the design of each component and the connection method.

[0055] See also Figures 7 to 9 , the adjusting member 2 plays an important role in connecting the prestressed device 3 with the spatial truss structure in the entire system. One end of its L-shaped hanging arm 21 is placed on the purlin 4, providing a basic support point for the entire system, and the other end is connected to the adjusting head 22 by bolts. The adjusting head 22 is provided with multiple bolt connection positions along the axial direction. This design can flexibly adjust the connection relationship between the prestressed device 3 and the node 11, so that the application and transmission process of the prestress can be accurately controlled to adapt to the diversified adjustment requirements of the preload and stress state of the support system under different working conditions. The prestressed device 3 can be selected from a jack, a prestressed steel bundle, and a prestressed anchor. It can actively provide prestress for the entire spatial truss support system, put the system in a compressed state in advance, and enhance its stability before bearing external loads, thereby effectively ensuring the resistance to external forces such as lateral soil pressure during foundation pit construction.

[0056] From the perspective of mechanical structure principles, the space truss support system achieves effective force transmission and balanced distribution through ingenious structural design. The purlin 4 serves as a supporting foundation, bears the top force from the prestressed device 3, and transmits the reaction force to the surrounding soil or structure. The steel support standard section 12 in the space truss structure bears the main axial pressure and tension, which are connected to each other through the node 11 to form a continuous force transmission path. The tetrahedral connecting rod structure is a key stabilizing component. The quadrilateral bottom structure composed of the oblique stabilizing rod 15 can resist the shear force and bending moment in the horizontal direction and disperse the horizontal force to each node 11 and the steel support standard section 12. The setting of the transverse stabilizer bar 14 at the diagonal position of the bottom of the quadrilateral effectively enhances the torsion and bending resistance of the bottom structure, while the transverse stabilizer bar 14 perpendicular to the bottom limits the deformation of the tetrahedral connecting rod structure in the height direction to prevent local instability. The connector 13 ensures the reliability of the connection between the oblique stabilizing rod 15 and the node 11, so that the force can be transmitted smoothly. The adjusting member 2 not only realizes the connection between the prestressed device 3 and the space truss structure, but also can change the direction and magnitude of force transmission by adjustment, adapt to the force changes under different working conditions, optimize the mechanical properties of the entire structure, and enable the space truss support system to remain stable and effectively play a supporting role in a complex mechanical environment.

[0057] For specific implementation, see Fig.10 and 11. When the tetrahedral pyramid connecting rod structure is provided with multiple layers, the tetrahedral pyramid connecting rod structure of the outer layer is in a proportional magnification relationship with the tetrahedral pyramid connecting rod structure of the inner layer. From the perspective of mechanical structure, this proportional magnification relationship is conducive to the uniform transmission and dispersion of force. Since the tetrahedral pyramid connecting rod structures of each layer are similar in shape, when subjected to external loads, such as soil pressure from the side wall of the foundation pit, the stress can smoothly transition between the layers of the structure along a similar path, avoiding the stress concentration phenomenon caused by structural mutations. For example, when the outer layer is subjected to a large pressure, the force can be reasonably distributed to the inner layer structure according to the proportional relationship, so that the entire space truss is like a collaborative whole, and each rod and node can give full play to its bearing capacity, thereby effectively improving the overall bearing capacity and stability of the system. In terms of the convenience of manufacturing and installation, the proportional magnification design makes the components of each layer of the structure have a certain degree of commonality and similarity. In the production and manufacturing process, similar processes and molds can be used to process rods and connectors of different layers, reducing production costs and production cycles. At the construction site, construction workers can form a standardized operating process for the installation steps and connection methods of each layer of the structure, reducing the installation difficulty and error rate caused by structural differences, improving construction efficiency, and helping to ensure the progress and quality of the project. From the perspective of space utilization and adaptability, this design can better adapt to the needs of foundation pits of different sizes and shapes. For larger-sized foundation pits, the coverage and support strength of the space truss support system can be flexibly expanded by increasing the number of layers of the tetrahedral pyramid connecting rod structure and maintaining a proportional enlargement relationship without redesigning complex structural forms. Whether it is a narrow subway foundation pit or a relatively wide municipal road foundation pit, the space truss support system can effectively adapt and support with this multi-layer proportionally enlarged tetrahedral pyramid connecting rod structure, providing stable and reliable protection for underground engineering construction.

[0058] The adjusting member 2 includes an L-shaped hanging arm 21 and an adjusting head 22 connected to each other. One end of the L-shaped hanging arm 21 is overlapped on the purlin 4, and the other end is connected to the adjusting head 22 by bolts; one end of the adjusting head 22 is connected to the prestressing device 3, and the other end is connected to the node 11; the adjusting head 22 is provided with multiple bolt connection positions along the axial direction, and the front and rear adjustment of the bolt connection positions meets the working condition requirements. The prestressing device 3 is one of a jack, a prestressed steel strand, and a prestressed anchor.

[0059] In the space truss support system of the present invention, the adjusting member 2 plays a key role in connection and adjustment. The L-shaped hanging arm 21 has a unique structural design, one end of which is firmly overlapped on the purlin 4, providing a reliable support foundation for the entire system. The other end is connected to the adjusting head 22 by bolts. This connection method not only ensures the stability of the connection, but also facilitates necessary adjustments during the construction process. As the core part of the adjusting member 2, the adjusting head 22 is tightly connected to the prestressing device 3 at one end, so that the prestress can be effectively transmitted to the entire space truss structure. The other end is connected to the node 11, ensuring the reasonable transmission and distribution of force between the standard units of the space truss.

[0060] A plurality of bolt connection positions are arranged axially on the adjusting head 22. In actual construction, due to the huge differences in the size, shape, external force and other working conditions of different foundation pits, the effective length of the adjusting member 2 can be accurately changed by flexibly adjusting the bolt connection position forward and backward, thereby adjusting the overall preload and stress state of the spatial truss support system. For example, when the side wall pressure of the foundation pit is large, the bolt connection position can be adjusted in a specific direction, so that the spatial truss structure can better resist the lateral force and effectively prevent the instability and deformation of the steel support.

[0061] As a key component for providing prestress, the prestressing device 3 can be selected from one of a jack, a prestressed steel bundle or a prestressed anchor. If a jack is used, it can generate a strong thrust or pull through hydraulic or mechanical principles, and can easily apply precise prestress to the space truss support system. The operator can accurately control the expansion and contraction of the jack according to the construction requirements and monitoring data to achieve the ideal prestressing effect. When using a prestressed steel bundle, the steel bundle will cause the space truss structure to generate prestress during the tensioning process. The advantage is that the prestress can be applied evenly over a large range, and the durability of the steel bundle is good, which can provide a stable prestress for the system for a long time. The prestressed anchor is mainly used to fix the two ends of the prestressed steel bundle to ensure that the prestress can be reliably maintained in the space truss support system, prevent the loss and relaxation of the prestress, and ensure the stability of the entire support structure during construction and even in the subsequent use process. By reasonably selecting and using the prestressing device 3, the prestressing level of the space truss support system can be flexibly adjusted according to the specific engineering requirements, so that it can adapt to various complex construction conditions, and provide solid protection for the safety of underground structure construction and the surrounding environment of the foundation pit.

[0062] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A space truss support system, characterized in that: It comprises a space truss support structure arranged between the purlins (4); Each of the spatial truss support structures comprises a spatial truss structure, adjustment members (2) arranged at both ends of the spatial truss structure, and a prestressing device (3) connected to the adjustment members (2); One side of the prestressed device (3) is supported on a surrounding purlin (4) of the foundation pit; The spatial truss structure comprises a plurality of sequentially connected spatial truss standard units (1), the spatial truss standard unit (1) comprising a node (11), a steel support standard section (12), a transverse stabilizer bar (14), and an oblique stabilizer bar (15), the plurality of steel support standard sections (12) being sequentially connected via the node (11), and the spatial truss structure is provided with at least one layer of a tetrahedral pyramid connecting rod structure formed by the transverse stabilizer bar (14) and the oblique stabilizer bar (15); In each layer of the tetrahedral pyramid connecting rod structure, four oblique stabilizing rods (15) are connected in sequence to form a quadrilateral bottom structure, and another four oblique stabilizing rods (15) form four edges of the tetrahedral pyramid connecting rod structure; In the quadrilateral bottom structure, two transverse stabilizer bars (14) are arranged at a diagonal position of the quadrilateral structure to achieve transverse support of the quadrilateral bottom, and one transverse stabilizer bar (14) is perpendicular to the quadrilateral bottom structure to achieve support in the height direction of the quadrangular pyramid connecting rod structure; The adjusting member (2) is adjustably connected between the prestressing device (3) and the node (11).

2. A space truss support system according to claim 1, characterized in that: The spatial truss standard unit (1) further comprises a connecting member (13), wherein the connecting member (13) is used for connecting the oblique stabilizing rod (15) and the node (11); An upper end plate (16) and a lower end plate (17) are respectively provided at both ends of the lateral stabilizer bar (14); a connecting plate (18) is connected to the upper end plate (16); the lateral stabilizer bar (14), the upper end plate (16), the lower end plate (17) and the connecting plate (18) are an integrated structure; In the quadrilateral bottom structure, the lateral stabilizer bar (14) is connected to the two oblique stabilizer bars (15) via a connecting plate (18), and the lateral stabilizer bar (14) is connected to the node (11) via a lower end plate (17).

3. A space truss support system according to claim 2, characterized in that: The node (11) is provided with a plurality of outwardly protruding connectors, and the connectors are used for connecting the node (11) to a transverse stabilizer bar (14) and for connecting the node (11) to an end plate of a connector (13).

4. A space truss support system according to claim 2, characterized in that: The connecting piece (13) is a cross ear plate.

5. A space truss support system according to claim 2, characterized in that: In the quadrilateral bottom structure of the quadrangular pyramid connecting rod structure, a diagonal line of the quadrilateral bottom structure is colinear with the axial direction of the steel support standard section (12).

6. A space truss support system according to claim 5, characterized in that: The quadrilateral bottom structure of the four-sided pyramid connecting rod structure is composed of a first oblique stabilizing rod, a second oblique stabilizing rod, a third oblique stabilizing rod, and a fourth oblique stabilizing rod connected in sequence, the first oblique stabilizing rod and the fourth oblique stabilizing rod are respectively connected to the first node through a connecting member (13), the second oblique stabilizing rod and the third oblique stabilizing rod are respectively connected to the third node through a connecting member (13), the second node located between the first node and the third node is respectively connected to the first lateral stabilizing rod, the second lateral stabilizing rod, and the third lateral stabilizing rod, and the first lateral stabilizing rod, the second lateral stabilizing rod, and the third lateral stabilizing rod form an inverted T-shaped support structure.

7. A space truss support system according to claim 6, characterized in that: Among the four edges of the four-sided pyramid connecting rod structure, the fifth oblique stabilizing rod and the sixth oblique stabilizing rod respectively form a pair of edges along the length direction of the steel support standard section (12), and the seventh oblique stabilizing rod and the eighth oblique stabilizing rod respectively form a pair of edges along the diameter direction of the steel support standard section (12), and one end of the fifth oblique stabilizing rod, the sixth oblique stabilizing rod, the seventh oblique stabilizing rod, and the eighth oblique stabilizing rod are connected to each other, and the connection point is the vertex of the four-sided pyramid connecting rod structure; The connecting plate (18) is a cross-shaped plate structure; one end of the first lateral stabilizer bar is connected to the first oblique stabilizer bar and the second oblique stabilizer bar via the connecting plate (18); the second lateral stabilizer bar is connected to the third oblique stabilizer bar and the fourth oblique stabilizer bar via one end of the connecting plate (18); and one end of the third lateral stabilizer bar is connected to one end of the fifth oblique stabilizer bar, the sixth oblique stabilizer bar, the seventh oblique stabilizer bar, and the eighth oblique stabilizer bar via the connecting plate (18).

8. The space truss support system according to claim 1, characterized in that: When the quadrangular pyramid connecting rod structure is provided with multiple layers, the quadrangular pyramid connecting rod structure of the outer layer is in an equal proportion to the quadrangular pyramid connecting rod structure of the inner layer.

9. The space truss support system according to claim 1, characterized in that: The adjusting member (2) comprises an L-shaped hanging arm (21) and an adjusting head (22) which are connected to each other, one end of the L-shaped hanging arm (21) is overlapped on the surrounding purlin (4), and the other end is connected to the adjusting head (22) by bolts; One end of the regulating head (22) is connected to the prestressing device (3), and the other end is connected to the node (11); The adjusting head (22) is provided with a plurality of bolt connection positions along the axial direction, and the front and rear adjustment of the bolt connection positions can meet the working condition requirements.

10. The space truss support system according to claim 1, characterized in that: The prestressing device (3) is one of a jack, a prestressed steel bundle, and a prestressed anchor.

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