A single-compartment UHPC-NC hybrid structure cable gallery

Abstract

A single-compartment UHPC-NC hybrid structure cable tunnel relates to the field of cable tunnel technology. The cable tunnel is composed of several assembled segments. Each segment includes a U-shaped prefabricated component at the bottom and an inverted U-shaped cover plate at the top. The U-shaped prefabricated component comprises a prefabricated body cast from ordinary concrete. At each of the four corners of the prefabricated body, UHPC material is used to cast a haunch structure. The outer end face of the haunch structure is flush with the front or rear end of the prefabricated body. Adjacent assembled segments are connected as a whole by prestressed steel bars penetrating the haunch structures. A water-proof mechanism is provided at the connection between the cover plate and the U-shaped prefabricated component. This invention features a simple structure, low manufacturing cost, high construction efficiency, high strength, water resistance, and good overall ductility.

Description

Technical Field

[0001] This invention relates to the field of cable tunnel technology, specifically to a single-compartment UHPC-NC hybrid structure cable tunnel. Background Technology

[0002] A trench-type utility tunnel refers to a public passageway in urban underground spaces used for the intensive laying of cables and communication lines, typically with a single-compartment cross-section. As the "nerve endings" of the urban underground integrated utility tunnel system, trench-type utility tunnels effectively solve the traffic congestion caused by repeated road excavation for the maintenance of outdated and aging municipal pipelines, as well as the "spider web" problem of urban roads. They improve the aesthetics of the urban environment and ensure smooth traffic flow. By laying various pipelines inside the tunnel, contact between the pipelines and groundwater, soil, and corrosive substances in the soil is avoided, extending their service life.

[0003] In the field of cement-based materials and applications, ultra-high performance concrete (UHPC), as an advanced cement-based material, provides a source of innovation and space for industrial-grade, lightweight, and durable engineering structures; the requirements of low carbon, green environmental protection, sustainability, and high-quality development have also promoted the application of UHPC in engineering construction.

[0004] Zhang Hao and others designed a prefabricated shallow-buried trench-type cable tunnel. The tunnel is composed of U-shaped prefabricated components and a top plate prefabricated component set above the U-shaped prefabricated components. The U-shaped prefabricated components, as the main components, are prefabricated into a "Z" shape, so that after assembly, the U-shaped prefabricated components mutually limit each other to form a whole, effectively overcoming the uneven settlement of the cable channel.

[0005] Zhang Wei et al. designed a combined UHPC and steel structure pipe gallery. Precast steel plates are set inside the UHPC precast integrated pipe gallery. The precast steel plates and the UHPC precast integrated pipe gallery are fixedly connected by multiple connecting components. Both transverse stiffening ribs and longitudinal stiffening ribs are fixed to the inner wall of the precast steel plates. Multiple transverse stiffening steel plates are fixed on both sides of the inner wall of the precast steel plates. Each transverse stiffening steel plate extends along the length of the precast steel plate.

[0006] Lu Nan et al. designed a resin concrete cable tunnel with prefabricated brackets. The tunnel includes multiple U-shaped prefabricated components, which are connected by an insertion method. The outer wall ribs of the prefabricated components are provided with multiple reinforcing ribs. The top of both sides of the prefabricated components are provided with bosses, and the bosses are provided with L-shaped slots for installing cover plates. The inner wall of the prefabricated components is provided with mounting holes for installing prefabricated brackets. Adjacent prefabricated brackets are assembled by splicing.

[0007] In summary, existing ordinary reinforced concrete cable tunnel connection structures are prone to damage, and the prestress values ​​that can be applied to the connectors—prestressed steel bars—are relatively small. Under vehicle loads and foundation settlement, excessive deflection and joint deformation may occur. Cable tunnels using UHPC as the component material and requiring the assembly of many steel plates and stiffeners have high economic costs. The arrangement of multiple auxiliary steel plates and a large number of stiffeners increases the amount of assembly work and reduces installation efficiency. Resin concrete cable tunnels with prefabricated brackets have prefabricated components made of resin concrete. Due to the immature resin concrete preparation technology, the cost of the cable tunnels produced is high, and this type of cable tunnel is prone to water seepage from the cover plate, causing serious water accumulation inside the tunnel. Summary of the Invention

[0008] To address the problems of existing technologies, this invention provides a single-compartment UHPC-NC hybrid structure cable tunnel. While maintaining the existing cable tunnel form, it employs an inverted U-shaped cover to prevent severe water accumulation within the tunnel. By combining UHPC material with ordinary concrete, the structure achieves stiffness and load-bearing capacity close to that of a UHPC cable tunnel, solving the technical problems of excessive deflection and joint deformation that may occur under vehicle loads and foundation settlement. Simultaneously, it reduces costs. This invention features a simple structure, high construction efficiency, and solves the problems of excessively high economic costs and large construction volume associated with existing cable tunnels using UHPC materials.

[0009] To solve the above problems, the technical solution of the present invention is as follows:

[0010] A single-compartment UHPC-NC hybrid structure cable tunnel is disclosed, comprising several assembled segments connected together. Each assembled segment includes a U-shaped prefabricated component at the bottom and an inverted U-shaped cover plate at the top. The U-shaped prefabricated component includes a prefabricated body cast from ordinary concrete. At the four corners of both ends of the prefabricated body, UHPC material is used to cast a haunch structure. The outer end face of the haunch structure is flush with the front or rear end of the prefabricated body. Adjacent assembled segments are connected into a whole by prestressed steel bars penetrating the haunch structure. A water-proof mechanism is provided at the connection between the cover plate and the U-shaped prefabricated component.

[0011] Preferably, the end of the axilla structure located at the bottom, away from the bottom corner of the precast body, extends inward to form a first protrusion, and the axilla structure located at the top extends horizontally inward to form a second protrusion. Both the first and second protrusions are provided with connecting holes that pass through the front and rear end faces. The connecting holes of adjacent assembly segments are opposite to each other. The prestressed steel rod passes through two opposite connecting holes and locks the adjacent axilla structures.

[0012] Preferably, the cover plate is cast from ordinary concrete.

[0013] Preferably, the leak-proof mechanism is a first water-swellable waterstop strip located at the connection between the cover plate and the U-shaped precast component.

[0014] Preferably, a second water-swellable sealing strip is provided between the opposite ends of adjacent assembled segments.

[0015] Preferably, the prestressed steel bar includes a bolt body, a steel washer, a rubber round washer, and an anchor nut. The bolt body passes through the corresponding connecting holes and is locked by the steel washer, the rubber round washer, and the anchor nut.

[0016] Preferably, a number of pins are pre-embedded between the precast body and the axle corner structure, with one end of the pins pre-embedded in the precast body and the other end pre-embedded in the axle corner structure.

[0017] Preferably, the left and right edges of the top of the cover plate, the inner corners of the cover plate, and the left and right edges of the top of the U-shaped preform are all rounded, and the curvature of the inner corner of the cover plate matches the curvature of the left and right edges of the top of the U-shaped preform.

[0018] The single-compartment UHPC-NC hybrid structure cable gallery of the present invention has the following beneficial effects:

[0019] 1. The prefabricated components of the cable tunnel assembly segment of the present invention are UHPC-NC hybrid structures. By strategically using UHPC, the load-bearing capacity of the structure and the deformation resistance of the joints can be effectively improved while controlling economic costs.

[0020] 2. The UHPC-NC hybrid structure can solve the problems of excessive deflection and excessive joint deformation of cable tunnel structures under vehicle loads and foundation settlement, thereby improving the load-bearing capacity of cable tunnels.

[0021] 3. By setting the first and second water-swellable sealing strips, the problem of water leakage in the cable tunnel is effectively solved. The cover plate is designed with rounded corners to prevent damage from bumps and avoids water leakage after damage.

[0022] 4. The assembly and connection parts of the U-shaped precast components and cover plates are designed with rounded corners to reduce stress concentration at the contact points and prevent external water from seeping into the corridor after the concrete is damaged. Attached Figure Description

[0023] Figure 1 A front view of the prefabricated assembly segment of the present invention;

[0024] Figure 2 This invention Figure 1 A magnified view of a portion of the image;

[0025] Figure 3 Assembly connection diagram of adjacent assembly segments of the present invention;

[0026] Figure 4 1. A structural diagram of the prestressed steel bar used in this invention;

[0027] 1-Cover plate; 2-Connecting hole; 3-Half corner structure; 4-First water-swellable sealing strip; 5-Pin; 6-Steel washer; 7-Anchor nut; 8-Rubber round washer. Detailed Implementation

[0028] The following description provides a detailed explanation of the embodiments of the present invention in a step-by-step manner. This description is only a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0029] In the description of this invention, it should be noted that the terms "upper," "lower," "left," "right," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or a specific orientational structure and operation. Therefore, they should not be construed as limiting this invention.

[0030] In the initial embodiment, the present invention provides a single-compartment UHPC-NC hybrid structure cable gallery, such as Figure 1-4 As shown, the cable tunnel is composed of several assembled segments connected together. Each assembled segment includes a U-shaped precast component at the bottom and an inverted U-shaped cover plate 1 at the top. The U-shaped precast component includes a precast body cast from ordinary concrete. At the four corners of both ends of the precast body, UHPC material is used to cast a haunch structure 3. The outer end face of the haunch structure 3 is flush with the front or rear end of the precast body. Adjacent assembled segments are connected into a whole by prestressed steel bars that penetrate the haunch structure. A water-proof mechanism is provided at the connection between the cover plate 1 and the U-shaped precast component.

[0031] In this embodiment, the U-shaped precast component is cast from two materials: UHPC and ordinary concrete. The strategic use of UHPC effectively improves the load-bearing capacity of the structure and the deformation resistance of the joints while controlling economic costs.

[0032] In a further embodiment, such as Figure 1-3As shown, the axilla structure 3 at the bottom extends inward from the corner of the precast body to form a first protrusion (not marked in the figure), and the axilla structure at the top extends horizontally inward to form a second protrusion. Both the first and second protrusions are reserved with connecting holes 2 that pass through the front and rear end faces. The connecting holes of adjacent assembly segments are opposite to each other. The prestressed steel rod passes through the two opposite connecting holes 2 and locks the adjacent axilla structures.

[0033] In a further embodiment, such as Figure 1-3 As shown, the cover plate 1 is cast from ordinary concrete.

[0034] In a further embodiment, such as Figure 1-3 As shown, the water-proof mechanism is a first water-swellable water-stop strip 4 installed at the connection between the cover plate 1 and the U-shaped prefabricated component, which can prevent water from entering the cable conduit.

[0035] In a further embodiment, such as Figure 3 As shown, a second water-swellable sealing strip (not shown in the figure) is provided between the opposite ends of adjacent assembled segments to prevent water leakage at the joint.

[0036] In a further embodiment, such as Figure 3 , 4 As shown, the prestressed steel bar includes a bolt body, a steel washer 6, a rubber round washer 8, and an anchor nut 7. The bolt body passes through the corresponding connecting holes and is locked by the steel washer 6, the rubber round washer 8, and the anchor nut 7.

[0037] In a further embodiment, such as Figure 3 As shown, several pins 5 are pre-embedded between the precast component body and the armpit corner structure. One end of each pin 5 is pre-embedded in the precast component body, and the other end is pre-embedded in the armpit corner structure. By pre-embedding the pins, the material interface is reinforced, thereby improving the ductility of the cable tunnel structure.

[0038] In a further embodiment, such as Figure 1 As shown, the left and right edges of the top of the cover plate, the inner corners of the cover plate, and the left and right edges of the top of the U-shaped precast component are all rounded. The curvature of the inner corner of the cover plate 1 matches the curvature of the left and right edges of the top of the U-shaped precast component. The purpose of rounding the top of the cover plate is to solve the problem of easy damage to the concrete at the corners of the existing cable tunnel cover plates and the easy water seepage after the concrete is damaged. The purpose of matching the curvature of the inner corner of the cover plate 1 with the curvature of the left and right edges of the top of the U-shaped precast component is to ensure that the two are tightly assembled and avoid damage and water leakage caused by stress concentration at the connection.

[0039] It should be noted that, if the economic cost is acceptable, the U-shaped precast component of the present invention can also be integrally cast using UHPC; at the same time, the prestressed steel bar of the present invention can also be reasonably replaced with high-strength bolts and other connecting parts that can perform similar functions.

Claims

1. A single-compartment UHPC-NC hybrid structure cable gallery, characterized in that: The cable tunnel is composed of several assembled segments. Each assembled segment includes a U-shaped precast component at the bottom and an inverted U-shaped cover plate at the top. The U-shaped precast component includes a precast body made of ordinary concrete. At the four corners of both ends of the precast body, UHPC material is used to cast a haunch structure. The outer end face of the haunch structure is flush with the front or rear end of the precast body. Adjacent assembled segments are connected into a whole by prestressed steel bars that penetrate the haunch structure. A water-proof mechanism is provided at the connection between the cover plate and the U-shaped precast component. The axilla structure at the bottom extends inward from the corner of the precast body to form a first protrusion, and the axilla structure at the top extends horizontally inward to form a second protrusion. Both the first and second protrusions are reserved with connecting holes that pass through the front and rear end faces. The connecting holes of adjacent assembly segments are opposite to each other. The prestressed steel bars pass through the two opposite connecting holes and lock the adjacent axilla structures. The cover plate is cast from ordinary concrete. Several pins are also pre-embedded between the precast body and the axle corner structure. One end of the pin is pre-embedded in the precast body and the other end is pre-embedded in the axle corner structure.

2. The single-compartment UHPC-NC hybrid structure cable gallery as described in claim 1, characterized in that: The aforementioned leak-proof mechanism is a first water-swellable waterstop strip installed at the connection between the cover plate and the U-shaped prefabricated component.

3. The single-compartment UHPC-NC hybrid structure cable gallery as described in claim 1, characterized in that: A second water-swellable sealing strip is provided between the opposite ends of adjacent assembly segments.

4. The single-compartment UHPC-NC hybrid structure cable gallery as described in claim 1, characterized in that: The prestressed steel bar includes a bolt body, a steel washer, a rubber round washer, and an anchor nut. The bolt body passes through the corresponding connecting holes and is locked by the steel washer, the rubber round washer, and the anchor nut.

5. A single-compartment UHPC-NC hybrid structure cable gallery as described in claim 1, characterized in that: The left and right edges of the top of the cover plate, the inner corners of the cover plate, and the left and right edges of the top of the U-shaped preform are all rounded. The curvature of the inner corner of the cover plate matches the curvature of the left and right edges of the top of the U-shaped preform.

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