Buckle type cable trench cover plate and design method thereof

Abstract

The invention relates to the technical field of power transformation engineering cable trenches, in particular to a buckle type cable trench cover plate and a design method thereof, and the trench cover plate comprises a top surface, a cantilever edge, a drip groove, a clamping groove, a clamping groove cover, stiffening ribs and steel bars. The novel ultrathin concrete buckle type cable trench cover plate finished product is directly and transversely lapped on the side wall of a cable trench, the top faces of the cover plates face upwards, the cover plates are spliced on the long sides in the cable trench direction, the clamping groove of one cover plate is lapped on the clamping groove of the other cover plate in a covering mode, and a whole is formed. And the clamping groove can play roles in water, oil, wind, sand and fire prevention. After the cover plate is integrally assembled, operation and maintenance personnel and robots can walk on the cover plate conveniently. The problem that the cable trench cover plate is difficult to open frequently on site is solved, the impact resistance and durability of the cable trench cover plate are improved, and local damage or cracks are avoided; the waterproof, oil-proof, fireproof, sand-proof and sand-proof problems of the cable trench are solved, the cable in the trench is effectively protected, and the cable trench has good economic, environmental and social benefits.

Description

Technical Field

[0001] This invention relates to the field of cable trench technology in substation engineering, and in particular to a snap-on cable trench cover and its design method. Background Technology

[0002] Cable trench covers in substation projects are used to cover U-shaped cable trenches used for laying cables. They protect the cables inside the trench and also facilitate the movement of maintenance personnel and robots. Cable trench covers are generally made of precast reinforced concrete, with a standard width of 500mm, a thickness ranging from 50mm to 300mm, and a length varying from 600mm to 2000mm depending on the cross-sectional width of the U-shaped cable trench.

[0003] Taking a 1m long, 0.5m wide, and 50mm thick concrete trench cover as an example, its weight is 67.5kg. Due to its weight, frequently opening the trench cover to inspect and maintain the cables inside is quite difficult for operators. Often, some trench covers are bumped and knocked, resulting in chipped edges, cracks, or even damage. Therefore, existing technology generally sets flat steel or angle steel frames around the edges of the cover to improve its service life, but this also increases the weight of the cover accordingly. For example, using 50mm wide and 5mm thick angle steel on all four sides adds 11.3kg to the weight.

[0004] To reduce the weight of the concrete cover slab, the first thought is to reduce its thickness. The conventional approach is to ensure the ground live load does not exceed 4 kN / m. 2 The reinforcing bars were replaced with wire mesh, and ordinary concrete was replaced with fine aggregate concrete. Ground live load refers to the variable load acting on the surface of the cable trench cover, i.e., temporary or mobile external forces, such as pressure exerted by maintenance personnel, repair equipment, vehicles, or other temporary heavy objects. However, due to the limitations of trench width and the needs of mechanical calculations, a minimum thickness of 50mm is generally required to ensure that, under maximum live load, the design requirement of crack width not exceeding 0.2mm and allowable deflection not exceeding 1 / 200 of the calculated span (net trench width + cover thickness) is met.

[0005] Subsequently, with the large-scale construction of substations and the exploration of relevant personnel, in order to facilitate the frequent opening of cable trenches, some cable trench covers were changed from concrete to composite materials, which greatly reduced the weight of the covers. However, after several years of use, the corrosion resistance and fire resistance of composite materials became prominent, and a large number of composite material trench covers had to be replaced.

[0006] Furthermore, although conventional cable trench covers appear tightly joined to the naked eye after installation, gaps still exist. Rainwater can seep into the cable trench through these gaps. In northern regions, fine sand can also be blown into the trench during sandstorms, making timely cleaning impossible and impacting the operating environment and durability of the cables. Additionally, near oil-containing equipment such as main transformers and high-voltage reactors, oil and fire from accidents can fall into the cable trench, severely compromising fire safety for the cables.

[0007] Therefore, existing cable trench covers cannot meet the requirements for waterproofing, oil resistance, fire prevention, wind and sand protection, corrosion resistance, and load-bearing capacity. Summary of the Invention

[0008] The purpose of this invention is to provide a snap-on cable trench cover and its design method, which can solve the technical problems that existing cable trench covers cannot meet the requirements of waterproofing, oil resistance, fire prevention, wind and sand protection, corrosion resistance, and stress resistance.

[0009] To achieve the above objectives, the present invention provides the following technical solution: This invention designs a snap-on cable trench cover, comprising: The cover plate body has a flat top. A front transverse stiffening rib is provided on the bottom surface of the cover plate body. The front transverse stiffening rib is provided along the width direction of the cable trench, and the length of the front transverse stiffening rib is less than the net width of the cable trench. One end of the front transverse stiffening rib extends to the outside of the cover plate body, cantilevering to form a protrusion. The top surface of the protrusion is flush with the bottom surface of the cover plate body, and a groove is provided at the upper end of the protrusion. The cover plate body has a cantilevered edge along its length direction, the cantilevered edge extends to the outside of the cable trench sidewall, and the length of the cover plate body is greater than the width of the outside of the cable trench; When two cable trench covers are spliced ​​together, one end of one cover overlaps the groove of the other cover to form a closed space.

[0010] The cable trench cover has a flat top surface, facilitating movement for maintenance personnel and robots. The cantilevered edges of the cable trench cover are located on the short side of the cover, with a thickness consistent with the overall cover thickness, protruding from both sides of the cable trench outer wall. This means that when the cable trench cover is placed horizontally over the cable trench, its length exceeds the width of the cable trench, allowing for a certain length of cantilever on both sides, facilitating lifting of the cover from the sides of the cable trench. A groove is provided on one edge of the cable trench cover to collect rainwater and windblown sand, which is discharged outside the cable trench due to the side slope, preventing seepage into the cable trench. The groove is a U-shaped channel located on one long side of the cover, running along its length. Water and oil flowing from the top surface of the cable trench cover to the side are caught by the groove and then flow outwards along the groove, effectively preventing water and oil from entering the cable trench. Due to the ultra-high strength characteristics of ultra-high performance concrete, the groove can be cast in one piece using a mold, eliminating the need for additional flat steel or angle steel frames and preventing localized damage. When two cover plates are joined together, the slot of one cover plate overlaps the slot of the other cover plate to form a closed space.

[0011] As a preferred embodiment, the cover plate body is made of special concrete with a thickness of 20mm, reducing its weight by more than half compared to a conventional 50mm thick cover plate. The special concrete has a compressive strength of not less than 120MPa and a tensile strength more than five times that of ordinary concrete, and incorporates steel fibers. The ultra-thin, ultra-high-performance concrete cover plate of this invention is only 20mm thick, reducing its weight by more than half compared to a conventional 50mm thick cover plate. The ultra-high-performance ultra-thin concrete has a compressive strength of 120MPa, four times that of ordinary C30 concrete, and a tensile strength more than five times that of ordinary concrete. It can replace some of the reinforcing steel, requiring only four reinforcing bars to meet the strength requirements. The ultra-high-performance concrete incorporates many fine steel fibers, effectively preventing crack formation. The steel fibers effectively inhibit the propagation and penetration of microcracks, transforming them into numerous uniformly distributed microcracks that are difficult to see with the naked eye, typically less than 0.1mm wide, thus achieving high toughness and high durability.

[0012] As a preferred embodiment, it also includes a rear transverse stiffening rib, which is arranged on the other side of the bottom surface of the cover plate body along the width direction of the cable trench, and the length of the rear transverse stiffening rib is less than the net width of the cable trench.

[0013] As a preferred embodiment, the cover plate body extends to the outer part of the rear transverse stiffening rib to form a slot cover. The slot cover mates with the slot, and the length of the slot cover is greater than the length of the slot. The bottom surface of the slot cover is flush with the top surface of the slot. The slot cantilever extends from the bottom edge of the transverse stiffening rib, and the top surface of the slot is flush with the bottom surface of the slot cover, ensuring that the entire top surface of the cover plate remains flat after the slot cover is placed on the slot. The top surface of the slot cover is flush with the top surface of the cover plate and is located on the other long side of the cover plate, also along the length direction of the cover plate. When two cover plates are spliced ​​along their long sides, the slot cover of one cover plate overlaps the slot of the other cover plate, making the slot form a closed space. The gap at the joint of the two cover plates is similar to that of a conventional cover plate, but because there is an additional slot below the joint, water, oil, or fine sand blown by the wind that seeps through the gap can only fall into the slot. Meanwhile, the slot effectively covers the gaps between the cable trench cover plates, preventing flammable oil from directly entering the cable trench, thus providing waterproofing, oil protection, wind and sand protection, and fire prevention. A slot cover is installed on the other side of the cable trench cover plate to cover the slot at the edge of the cover plate, ensuring a smooth and flat surface after the two cover plates are properly joined, without affecting the appearance or allowing normal walking on it.

[0014] As a preferred embodiment, the system also includes two longitudinal stiffening ribs. Both longitudinal stiffening ribs are positioned along the length of the cable trench at the bottom of the cover plate body. These two longitudinal stiffening ribs overlap with the front and rear transverse stiffening ribs, forming a reinforcing ring at the bottom of the cover plate body. The stiffening ribs are located on the four sides of the cover plate, on the bottom surface of the trench cover. After normal installation, the top surface of the cover plate is flat, and the stiffening ribs on the bottom surface are not visible. The stiffening ribs act like beams around the perimeter of the trench cover, protruding from the bottom surface of the plate. The thickness of the protrusion is approximately the same as the thickness of the plate, and the width is slightly greater than the width of the plate. First, to meet the stress requirements of the trench cover, a continuous steel bar is installed inside the stiffening rib, which acts as a beam to support the slab from all sides, thereby minimizing the overall thickness of the slab. Second, for process requirements, the stiffening ribs along the width of the slab are inserted into the inner side of the trench walls on both sides of the cable trench, preventing the cable trench cover from moving to the sides. The stiffening ribs along the length of the slab can be used to set the slots, so that the slots are lower than the surface of the trench cover. After the slot cover is placed on the slot, the top surface of the entire trench cover can remain flat.

[0015] Furthermore, the outer distance between the two longitudinal stiffening ribs is less than the net width of the cable trench, and the two longitudinal stiffening ribs are respectively clamped on the inner side of the cable trench sidewall. During installation, the longitudinal stiffening ribs are clamped on the inner side of the cable trench sidewall to prevent the trench cover from sliding on the left and right sides, and to act as beams for the cable trench cover, making the cable trench cover thinner.

[0016] Furthermore, the outer distance between the two longitudinal stiffening ribs is greater than the net width of the cable trench. The two longitudinal stiffening ribs are installed on the upper part of the cable trench sidewall, and a sealing strip is installed at the bottom of the cover plate body inside the longitudinal stiffening ribs. The longitudinal stiffening ribs are installed on the upper part of the cable trench sidewall, and a sealing strip is added to the bottom of the cover plate for sealing. This can shorten the length of the cover plate while ensuring waterproof sealing, making it easier to open the cover plate.

[0017] Furthermore, continuous reinforcing bars are arranged inside the two longitudinal stiffening ribs, the front transverse stiffening rib, and the rear transverse stiffening rib. To meet the load-bearing requirements of the trench cover, continuous reinforcing bars are placed within the stiffening ribs, acting as beams to support the slab from all sides, thus minimizing the overall thickness of the slab. These reinforcing bars are only located within the stiffening ribs; the rest of the cable trench cover has no reinforcing bars. Conventional cable trench covers require double-layered, bidirectional reinforcing bars; in contrast, ultra-high performance concrete covers significantly reduce the amount of reinforcing bars used. The reinforcing bars in the stiffening ribs primarily serve a load-bearing function, ensuring that the overall load-bearing capacity and deformation of the trench cover meet the requirements.

[0018] As a preferred embodiment, a drip groove is also included, which is located at the bottom end of the cantilevered side of the cover plate body, along the width direction of the cover plate body. When rainwater flows from the top surface of the cable trench cover plate to both sides, it can drip off from the drip groove, preventing further seepage into the bottom surface of the cable trench cover plate and the cable trench.

[0019] This invention also provides a design method for a snap-on cable trench cover, comprising the following steps: The design requirements for cable trench covers are as follows: crack width not greater than 0.2mm, deflection not greater than 1 / 200 of the calculated span; The net width and live load requirements of the cable trench were determined, and the thickness of the cover plate body was calculated to be 20mm based on the mechanical properties of the special concrete. Stiffening ribs are provided on all four sides of the bottom surface of the cover plate body, and continuous steel bars are arranged in the stiffening ribs; A slot is provided on the stiffening rib on one side of the long side of the cover plate body, and a slot cover that mates with the slot is provided on the other side. A cantilevered edge and a drip groove are provided on the short side of the cover plate body; The anti-slip pattern on the top surface of the cover plate is made using fair-faced concrete technology. Calculate the design load value, quasi-permanent load value, mid-span strength, mid-span deflection, and mid-span crack respectively to verify whether the design requirements are met.

[0020] As a preferred option, the specially formulated concrete has a compressive strength of not less than 120 MPa, a tensile strength more than 5 times that of ordinary concrete, and is mixed with steel fibers.

[0021] As a preferred option, the size of the stiffening ribs is determined based on the stress calculation of the cover plate, in order to replace the conventional double-layer bidirectional reinforcement.

[0022] The beneficial effects of this invention are: This invention provides a snap-on cable trench cover and its design method, which solves the problem of frequent on-site opening difficulties of cable trench covers, improves their impact resistance and durability, and avoids local damage or cracks; it also solves the problems of waterproofing, oil prevention, fire prevention, and wind and sand prevention of cable trenches, optimizes the operating environment of cable trenches, and effectively protects the cables in the trench; it effectively improves resource utilization, avoids data waste, and also improves construction and maintenance efficiency.

[0023] This invention meets the requirements for waterproofing, oil resistance, fireproofing, wind and sand protection, corrosion resistance, and load-bearing capacity of cable trenches, while improving the efficiency of construction and cable maintenance. This invention offers significant economic, environmental, and social benefits. The advantages of this invention are as follows: 1. Weight reduction and ease of opening: Due to the use of ultra-thin design (20mm thickness) and ultra-high performance concrete, the weight of the cover plate is reduced by more than 50% compared with the conventional 50mm cover plate. This weight reduction effect is directly caused by the reduction in thickness and the high strength of the material, which allows maintenance personnel to easily and frequently open the cover plate, improving maintenance efficiency.

[0024] 2. Improved structural strength and durability: The high strength of ultra-high performance concrete (compressive strength 120MPa) makes its tensile strength 5 times that of ordinary concrete, which can directly replace most steel bars, requiring only 4 steel bars in the stiffening ribs; at the same time, the incorporation of steel fibers inhibits the propagation of microcracks, enhances the impact resistance of the cover plate, and avoids chipping and corner breakage. This effect is directly achieved by the material composition and stiffening rib design.

[0025] 3. Sealing and protection performance: The snap-fit ​​design of the slot and slot cover forms a closed space through mechanical splicing. Rainwater, oil or sand are guided to both sides of the slot and discharged to prevent seepage into the cable trench. This sealing effect is directly brought about by the groove-cantilever structure. At the same time, the slot covers the gaps to prevent the intrusion of flammable oil and improve fire resistance.

[0026] 4. Resource efficiency and environmental friendliness: Reduced concrete usage and simplified steel reinforcement directly reduce material consumption; improved cover plate durability reduces replacement frequency, thereby reducing engineering waste and meeting energy conservation and environmental protection requirements. Attached Figure Description

[0027] Figure 1 This is a top view of the cable trench cover.

[0028] Figure 2 for Figure 1 Cross-sectional view at point AA in Example 1.

[0029] Figure 3 for Figure 1 Cross-sectional view at point AA in Example 2.

[0030] Figure 4 for Figure 1 Cross-sectional view at point BB.

[0031] Figure 5 This is a schematic diagram of the splicing of two cable trench covers.

[0032] Figure 6 This is the load-deflection curve diagram of the present invention.

[0033] Explanation of reference numerals in the attached figures: 10. Cable trench cover; 11. Cable trench; 12. Cable trench sidewall; Cable trench cover 10: cover body 1, cantilevered edge 2, drip groove 3, longitudinal stiffening rib 4, slot 5, slot cover 6, front transverse stiffening rib 7, rear transverse stiffening rib 8. Detailed Implementation

[0034] To make the technical problems solved by the present invention, the technical solutions adopted, and the technical effects achieved clearer, the technical solutions of the present invention will be further described below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only for explaining the present invention and not for limiting the present invention. Furthermore, it should be noted that, for ease of description, only the parts related to the present invention are shown in the accompanying drawings, not all of them.

[0035] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The terms "first position" and "second position" refer to two different positions.

[0036] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections or detachable connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.

[0037] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of the invention include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0038] This invention belongs to the field of substations and converter stations, and relates to outdoor power distribution assembly areas and indoor cable trench covers of various voltage levels within the substation. To facilitate the frequent opening of cable trench covers in substations, meet the requirements for waterproofing, oil resistance, fireproofing, wind and sand protection, corrosion resistance, and load-bearing capacity of cable trenches, and improve the efficiency of construction and cable maintenance, this invention designs a better cable trench cover.

[0039] This invention can solve the following technical problems: 1) Solving the problem of frequent opening difficulties. The present invention is an ultra-thin concrete trench cover. Taking a conventional concrete trench cover that is 1m long, 0.5m wide, and 50mm thick as an example, its weight is 67.5kg. The ultra-thin concrete cover of the present invention is only 20mm thick, which reduces the weight by more than half compared with conventional covers, making it easier for maintenance personnel to open.

[0040] 2) Solving the problem of low strength in conventional concrete. This invention is an ultra-high performance concrete cover plate. The compressive strength of ultra-high performance concrete is 120 MPa, which is 4 times that of ordinary C30 concrete, and its tensile strength is more than 5 times that of ordinary concrete. It can replace some of the reinforcing steel. For a conventional 1m wide cable trench cover plate, the strength is 4kN / m... 2 Under live load, to meet the design requirements that the crack width is no more than 0.2mm and the allowable deflection is no more than 1 / 200 of the calculated span (net width of the trench + cover plate thickness), the cover plate thickness is conventionally 50mm, and the reinforcement needs to be arranged in two layers and in two directions. However, the ultra-high performance concrete cover plate of this invention is only 20mm thick and replaces most of the reinforcement, requiring only 4 reinforcement bars to meet the strength requirements.

[0041] 3) Solving the problem of easy local damage. This invention is an ultra-high performance concrete trench cover. Utilizing the high strength of ultra-high performance concrete, it eliminates the need for flat steel or angle steel frames around the edges of the cover to extend its service life. Tests have verified that this trench cover will not develop chipped edges or missing corners even after being subjected to impacts.

[0042] 4) Solving the problem of easy cracking. This invention is an ultra-high performance concrete trench cover. Because the ultra-high performance concrete incorporates many fine steel fibers, it can effectively prevent cracking. The steel fibers effectively inhibit the propagation and penetration of microcracks, transforming them into a large number of evenly distributed microcracks that are difficult to see with the naked eye (usually less than 0.1 mm in width), thereby achieving high toughness and high durability.

[0043] 5) Solve the problems of waterproofing, oil resistance, fire prevention, and wind and sand protection. This invention is a snap-on trench cover. A groove is set on one edge of the cable trench cover to facilitate the collection of rainwater and wind and sand, which are discharged outside the cable trench by the side slope to prevent seepage into the cable trench. A groove cover is set on the other side of the cable trench cover to cover the groove on the edge of the cover, so that the surface of the two cover plates is flat and smooth after normal splicing, without affecting the appearance and normal walking on it.

[0044] 6) Solving the problem of resource waste. This invention provides a thinner and lighter trench cover, which reduces the amount of concrete used in the trench cover, eliminates the need for conventional steel reinforcement, improves the durability of the trench cover, increases construction and maintenance efficiency, reduces the amount of work required to repair or replace trench covers that are easily damaged, and promotes energy conservation and environmental protection.

[0045] In this invention, the direction along the length of the cable trench cover is defined as transverse, and the direction along the width of the cable trench cover is defined as longitudinal.

[0046] This invention provides a snap-on cable trench cover, comprising: The cover plate body has a flat top. A front transverse stiffening rib is provided on the bottom surface of the cover plate body. The front transverse stiffening rib is provided along the width direction of the cable trench, and the length of the front transverse stiffening rib is less than the net width of the cable trench. One end of the front transverse stiffening rib extends to the outside of the cover plate body, cantilevering to form a protrusion. The top surface of the protrusion is flush with the bottom surface of the cover plate body, and a groove is provided at the upper end of the protrusion. The cover plate body has a cantilevered edge along its length direction, the cantilevered edge extends to the outside of the cable trench sidewall, and the length of the cover plate body is greater than the width of the outside of the cable trench; When two cable trench covers are spliced ​​together, one end of one cover overlaps the groove of the other cover to form a closed space.

[0047] The cable trench cover has a flat top surface, facilitating movement for maintenance personnel and robots. The cantilevered edges of the cable trench cover are located on the short side of the cover, with a thickness consistent with the overall cover thickness, protruding from both sides of the cable trench outer wall. This means that when the cable trench cover is placed horizontally over the cable trench, its length exceeds the width of the cable trench, allowing for a certain length of cantilever on both sides, facilitating lifting of the cover from the sides of the cable trench. A groove is provided on one edge of the cable trench cover to collect rainwater and windblown sand, which is discharged outside the cable trench due to the side slope, preventing seepage into the cable trench. The groove is a U-shaped channel located on one long side of the cover, running along its length. Water and oil flowing from the top surface of the cable trench cover to the side are caught by the groove and then flow outwards along the groove, effectively preventing water and oil from entering the cable trench. Due to the ultra-high strength characteristics of ultra-high performance concrete, the groove can be cast in one piece using a mold, eliminating the need for additional flat steel or angle steel frames and preventing localized damage. When two cover plates are joined together, the slot of one cover plate overlaps the slot of the other cover plate to form a closed space.

[0048] In one embodiment, the cover plate body is made of special concrete with a thickness of 20mm, reducing its weight by more than half compared to a conventional 50mm thick cover plate. The special concrete has a compressive strength of not less than 120MPa and a tensile strength more than five times that of ordinary concrete, and incorporates steel fibers. The ultra-thin, ultra-high-performance concrete cover plate of this invention is only 20mm thick, reducing its weight by more than half compared to a conventional 50mm thick cover plate. The ultra-high-performance ultra-thin concrete has a compressive strength of 120MPa, four times that of ordinary C30 concrete, and a tensile strength more than five times that of ordinary concrete. It can replace some of the reinforcing steel, requiring only four reinforcing bars to meet the strength requirements. The ultra-high-performance concrete incorporates many fine steel fibers, effectively preventing crack formation. The steel fibers effectively inhibit the propagation and penetration of microcracks, transforming them into numerous uniformly distributed microcracks that are difficult to see with the naked eye, typically less than 0.1mm wide, thus achieving high toughness and high durability.

[0049] In one embodiment, a rear transverse stiffening rib is further included, which is disposed on the other side of the bottom surface of the cover plate body along the width direction of the cable trench, and the length of the rear transverse stiffening rib is less than the net width of the cable trench.

[0050] In one embodiment, the cover plate body extends to the outer portion of the rear transverse stiffening rib to form a slot cover. The slot cover mates with the slot, and the length of the slot cover is greater than the length of the slot. The bottom surface of the slot cover is flush with the top surface of the slot. The slot cantilever extends from the bottom edge of the transverse stiffening rib, and the top surface of the slot is flush with the bottom surface of the slot cover, ensuring that the entire top surface of the cover plate remains flat after the slot cover is placed on the slot. The top surface of the slot cover is flush with the top surface of the cover plate and is located on the other long side of the cover plate, also along the length direction of the cover plate. When two cover plates are spliced ​​along their long sides, the slot cover of one cover plate overlaps the slot of the other cover plate, forming a closed space. The gap at the joint of the two cover plates is similar to that of a conventional cover plate, but because there is an additional slot below the joint, water, oil, or fine sand blown by the wind that seeps through the gap can only fall into the slot. Meanwhile, the slot effectively covers the gaps between the cable trench cover plates, preventing flammable oil from directly entering the cable trench, thus providing waterproofing, oil protection, wind and sand protection, and fire prevention. A slot cover is installed on the other side of the cable trench cover plate to cover the slot at the edge of the cover plate, ensuring a smooth and flat surface after the two cover plates are properly joined, without affecting the appearance or allowing normal walking on it.

[0051] In one embodiment, two longitudinal stiffening ribs are also included. Both longitudinal stiffening ribs are arranged along the length of the cable trench at the bottom of the cover plate body. These two longitudinal stiffening ribs overlap with the front and rear transverse stiffening ribs, forming a ring of reinforcement at the bottom of the cover plate body. The stiffening ribs are located on the four sides of the plate, on the bottom surface of the trench cover plate. After normal installation, the top surface of the cover plate is flat, and the stiffening ribs on the bottom surface are not visible. The stiffening ribs are equivalent to beams around the trench cover plate, protruding from the bottom surface of the plate. The thickness of the protrusion is approximately the same as the thickness of the plate, and the width is slightly greater than the width of the plate. First, to meet the stress requirements of the trench cover, a continuous steel bar is installed inside the stiffening rib, which acts as a beam to support the slab from all sides, thereby minimizing the overall thickness of the slab. Second, for process requirements, the stiffening ribs along the width of the slab are inserted into the inner side of the trench walls on both sides of the cable trench, preventing the cable trench cover from moving to the sides. The stiffening ribs along the length of the slab can be used to set the slots, so that the slots are lower than the surface of the trench cover. After the slot cover is placed on the slot, the top surface of the entire trench cover can remain flat.

[0052] In one embodiment, the outer distance between the two longitudinal stiffening ribs is less than the net width of the cable trench, and the two longitudinal stiffening ribs are respectively clamped on the inner side of the cable trench sidewall. During installation, the longitudinal stiffening ribs are clamped on the inner sidewall of the cable trench to prevent the trench cover from sliding on the left and right sides, and to act as beams for the cable trench cover, making the cable trench cover thinner.

[0053] In another embodiment, the outer distance between the two longitudinal stiffening ribs is greater than the net width of the cable trench. The two longitudinal stiffening ribs are respectively installed above the sidewall of the cable trench, and a sealing strip is provided at the bottom of the cover body inside the longitudinal stiffening ribs. The longitudinal stiffening ribs are installed above the sidewall of the cable trench, and a sealing strip is added to the bottom of the cover to ensure waterproof sealing while shortening the length of the cover and facilitating the opening of the cover.

[0054] In one embodiment, continuous reinforcing bars are arranged inside the two longitudinal stiffening ribs, the front transverse stiffening rib, and the rear transverse stiffening rib. To meet the load-bearing requirements of the trench cover, continuous reinforcing bars are placed within the stiffening ribs, acting as beams to support the slab from all sides, thus minimizing the overall thickness of the slab. These reinforcing bars are only located within the stiffening ribs; the rest of the cable trench cover has no reinforcing bars. Conventional cable trench covers require double-layered, bidirectional reinforcing bars; in contrast, ultra-high performance concrete covers can significantly reduce the amount of reinforcing bars used. The reinforcing bars in the stiffening ribs primarily serve a load-bearing function, ensuring that the overall load-bearing capacity and deformation of the trench cover meet the requirements.

[0055] In one embodiment, a drip groove is also included, which is disposed at the bottom end of the cantilevered side of the cover body along the width direction of the cover body. When rainwater flows from the top surface of the cable trench cover to both sides, it can drip off from the drip groove, preventing further seepage into the bottom surface of the cable trench cover and into the cable trench.

[0056] In one embodiment, front transverse stiffening ribs and rear transverse stiffening ribs are respectively provided at the front and rear ends of the bottom of the cover plate body; The upper end of the front transverse stiffening rib is provided with a slot, and the side of the rear transverse stiffening rib is provided with a slot cover that mates with the slot. The slot cover extends rearward along the cover plate body, and the top surface of the slot is flush with the bottom surface of the slot cover. The lengths of the front transverse stiffening ribs and the rear transverse stiffening ribs are both less than the net width D of the cable trench; The cover plate body has cantilevered edges on both the left and right sides, which extend to the outer side of the cable trench sidewall. The length of the cover plate body is greater than the width of the outer side of the cable trench.

[0057] This invention also provides a design method for a snap-on cable trench cover, comprising the following steps: Step 1: Determine the design requirements for the cable trench cover: the crack width should not exceed 0.2mm, and the deflection should not exceed 1 / 200 of the calculated span; Step 2: Determine the net width and live load requirements of the cable trench, and calculate the thickness of the cover plate body to be 20mm based on the mechanical properties of the special concrete; Step 3: Stiffening ribs are set on the four sides of the bottom surface of the cover plate body, and continuous steel bars are placed in the stiffening ribs; Step 4: Set a slot on the stiffening rib on one side of the long side of the cover plate body, and set a slot cover on the other side to cooperate with the slot. Step 5: Install a cantilevered edge and a drip groove on the short side of the cover plate body; Step 6: Use fair-faced concrete to create an anti-slip pattern on the top surface of the cover plate; Step 7: Calculate the design load value, quasi-permanent load value, mid-span strength, mid-span deflection, and mid-span crack respectively, and verify whether they meet the design requirements.

[0058] The specially made concrete has a compressive strength of not less than 120 MPa, a tensile strength more than 5 times that of ordinary concrete, and is mixed with steel fibers.

[0059] The size of the stiffening ribs is determined based on the stress calculation of the cover plate, in order to replace the conventional double-layer bidirectional reinforcement.

[0060] It should be understood that the specific order or hierarchy of steps in the process disclosed in this invention is an example of an exemplary method. Based on design preferences, it should be understood that the specific order or hierarchy of steps in the process may be rearranged without departing from the scope of this disclosure. The appended method claims provide elements of various steps in an exemplary order and are not intended to limit the specific order or hierarchy described.

[0061] In one embodiment, the specially formulated concrete has a compressive strength of 180 MPa and a tensile strength of 10 MPa.

[0062] In practical applications, the cable trench cover measures 1900 mm × 500 mm, with four-sided ribs of 50 mm thickness, a middle span of 25 mm, an average thickness of 37 mm, a weight of 69.5 kg, a design live load of 4.0 kN / m², and a crack control level of three. Ultra-high performance concrete is tested according to the following standards: "Code for Acceptance of Construction Quality of Concrete Structures" (GB 50204-2015); "Standard for Test Methods of Concrete Structures" (GB / T 50152-2012).

[0063] Based on the calculation of a flexible cover plate, the clear span of the plate is 1.4m, the calculated span is: Lx = 1.50m (clear span + 1 / 2 support width), the cover plate width is Ly = 0.500m, the cover plate thickness is h = 20mm, and the cover plate density is 25.00kN / m³. 3 The standard value of the cover plate's self-weight load is 0.993 kN / m. 2 Partial factor for dead load γ G =1.30, live load partial factor γ Q =1.50, uniformly distributed live load q =4.00kN / m 2 The concrete has a compressive strength of 180 MPa and a tensile strength of 10 MPa.

[0064] Calculate the design load, quasi-permanent load, mid-span strength, mid-span deflection, and mid-span crack using the following formulas: 2.1 Design load values: Calculation formula: Design load value = γ G ×Permanent Load+ γ Q × γ l ×Live load; Uniformly distributed load = 1.30 × 0.993 + 1.50 × 1.00 × 4.00 = 7.3 kN / m 2 ; In the formula, γ G For the permanent load partial factor; γ Q This is the live load partial factor; γ l To account for the adjustment factor for the design service life, 1.0 is taken for 50 years; 2.2 Quasi-permanent load values: Calculation formula: Quasi-permanent load value = Dead load + ψ q ×Live load; Uniformly distributed load = 0.993 + 0.60 × 4.00 = 3.33 kN / m 2 ; In the formula, ψ q This is the quasi-permanent value coefficient for live load; 2.3 Mid-span strength: Design value of mid-span bending moment for a 0.5m wide cover plate: M = 1 / 8 × 7.3 × 0.5 × 1.5^2 = 1.03 kN.m; Bending stress = 1.03 / (0.5×0.037^2 / 6) = 9 MPa < 10 MPa; Therefore, in terms of mid-span strength, the tensile strength of ultra-high performance concrete can meet the design requirements.

[0065] 2.4 Mid-span deflection: According to Clause 3.4.3 of the "Standard for Design of Concrete Structures" GB50010, the limit for slab deflection is l0 / 200 (l0 is the calculated span): 1500mm / 200=7.5mm.

[0066] In the test, when the cumulative deflection reached 7.68 mm (exceeding 7.5 mm) through progressive loading, the load reached 9.593 kN / m. 2 This has far exceeded the actual requirement of 7.3 kN / m. 2It can be seen that the mid-span deflection meets the design requirements, as shown in the load-deflection curve. Figure 6 As shown, the corresponding values ​​for load and deflection are detailed in the table below.

[0067] 2.5 Mid-span crack: According to Clause 3.4.5 of the "Standard for Design of Concrete Structures" GB50010, the limit for slab cracks is 0.2 mm.

[0068] Through on-site loading tests, the cover plate was loaded to 3.164 kN / m. 2 No cracks appeared in the component at (1.0 times the quasi-permanent combination value of the load). Loading to 7.594 kN / m... 2 Cracks appeared in the component at 2.4 times the quasi-permanent combination load value. The load reached 10.963 kN / m. 2 At 1.2 times the basic load combination value, the maximum crack width reached 0.12m. Within the crack width limit requirement, the load far exceeded the actual requirement of 7.3kN / m. 2 It is evident that the mid-span crack meets the design requirements.

[0069] The load-deflection data summary table is as follows: For details of the load-deflection curve, please refer to [link / reference]. Figure 6 As shown, when designing the mid-span deflection, the load reached 9.593 kN / m when the cumulative deflection reached 7.68 mm (exceeding 7.5 mm) through progressive loading in the experiment. 2 This has far exceeded the actual requirement of 7.3 kN / m. 2 It is evident that the mid-span deflection meets the design requirements.

[0070] This invention is achieved through the following technical solution. The cable trench cover includes: a top surface of the cover, a cantilevered edge, a drip groove, a slot, a slot cover, stiffening ribs, and reinforcing bars.

[0071] The cable trench cover, with its top surface facing upwards, is made using fair-faced concrete technology and features raised anti-slip patterns for easy walking by maintenance personnel. Because the cover is made of ultra-high performance, high-strength concrete, its thickness can be reduced by more than half compared to conventional covers for the same span, allowing it to meet load-bearing and deformation requirements without the need for steel reinforcement. Furthermore, the inclusion of steel fibers in the ultra-high performance concrete easily achieves zero cracks on the concrete trench cover surface.

[0072] The cantilevered edge of the cable trench cover is located on the short side of the cover plate, and its thickness is the same as the overall thickness of the cover plate. It protrudes from both sides of the outer wall of the cable trench. That is, after the cable trench cover is laid horizontally above the cable trench, the length of the cable trench cover is greater than the width of the cable trench, and both sides can be cantilevered for a certain length, which makes it convenient to lift the cable trench cover from both sides of the cable trench.

[0073] The drip groove is located at the bottom end of the cantilevered side of the cable trench cover, along the width direction of the cover. When rainwater flows from the top surface of the cable trench cover to both sides, it drips from the drip groove, preventing further seepage into the bottom surface of the cable trench cover and into the cable trench.

[0074] The aforementioned slot is a U-shaped groove located on one of the long sides of the cover plate, along the length of the cover plate. Water and oil flowing from the top surface of the cable trench cover plate to the side can be caught by the slot, and then flow out of the cable trench along both sides, effectively preventing water and oil from flowing into the cable trench. Due to the ultra-high strength characteristics of ultra-high performance concrete, the slot can be cast in one piece using a mold, without the need for additional flat steel or angle steel frames, and without causing localized damage.

[0075] The top surface of the slot cover is flush with the top surface of the cover plate and is located on the other long side of the cover plate, also along the length of the cover plate. When the two cover plates are spliced ​​along their long sides, the slot cover of one cover plate overlaps the slot of the other cover plate, forming a closed space within the slot. The gap at the joint of the two cover plates is similar to that of a conventional cover plate, but because there is an additional slot below the joint, water, oil, or wind-blown sand that seeps through the gap can only fall into the slot. At the same time, the slot effectively covers the gap at the joint of the trench cover plates, effectively preventing accidental oil with fire from directly entering the cable trench, thus playing a role in waterproofing, oil prevention, wind and sand prevention, and fire prevention.

[0076] The stiffening ribs are installed on the four sides of the cover plate, located on the bottom surface of the trench cover plate. After normal installation, the top surface of the cover plate is flat, and the stiffening ribs on the bottom surface are not visible. The stiffening ribs include longitudinal stiffening ribs 4 and transverse stiffening ribs 7. The longitudinal stiffening ribs 4 are set along the width direction of the cover plate, and the transverse stiffening ribs 7 are set along the length direction of the cover plate. The two longitudinal stiffening ribs 4 and the two transverse stiffening ribs 7 overlap to form a complete circle. The stiffening ribs are equivalent to the beams around the trench cover plate, protruding from the bottom surface of the cover plate. The thickness of the protrusion is about the same as the thickness of the plate, and the width is slightly larger than the width of the plate.

[0077] Firstly, in order to meet the stress requirements of the trench cover, a continuous steel bar is installed inside the stiffening rib, which acts as a beam to support the slab from all sides, thereby minimizing the overall thickness of the cover.

[0078] Secondly, for process requirements, the stiffening ribs along the width of the cover plate are secured to the inner sides of the cable trench walls on both sides, preventing the cable trench cover plate from moving to either side. The stiffening ribs along the length of the cover plate can be used to set the slots, making the slots lower than the surface of the trench cover plate. After the slot cover is placed on top of the slot, the top surface of the entire trench cover plate can remain flat. The specific size of the stiffening ribs can be determined based on the stress calculations of the cable trench cover plate.

[0079] The reinforcing bars are only located within the stiffening ribs; the rest of the cable trench cover has no reinforcing bars. Conventional cable trench covers require reinforcing bars in both the upper and lower layers and in both directions. In contrast, ultra-high performance concrete covers can significantly reduce the amount of reinforcing bars used. The reinforcing bars in the stiffening ribs primarily serve a load-bearing function, ensuring that the overall load-bearing capacity and deformation of the trench cover meet requirements. The specific size of the reinforcing bars can be determined based on the stress calculations of the trench cover.

[0080] The present invention will now be described in detail with reference to the accompanying drawings: This invention relates to a novel ultra-thin concrete snap-on cable trench cover. It is directly placed horizontally onto the sidewall 12 of the cable trench, with the top surface of the cover 10 facing upwards. The covers are spliced ​​along the long side of the cable trench 11, with the slot 6 of one cover overlapping the slot 5 of another, forming a single unit. The slots provide waterproofing, oil resistance, wind and sand protection, and fire resistance. Once assembled, the cover allows maintenance personnel and robots to move freely on it.

[0081] Appendix Figure 1 This is a top view of the finished trench cover, showing its top surface. Two short sides cantilever from the outer sidewall of the cable trench. One long side has a slot, slightly lower than the top surface of the cover, while the other long side has a slot cover flush with the top surface. Anti-slip patterns are incorporated into the top surface during precast concrete installation. The top surface of the cover features raised anti-slip patterns. The short sides cantilever from the outer side of the cable trench wall, while one long side has a slot 5, and the other side has a slot cover 6. The slot covers overlap the slots of adjacent cover plates, forming a continuous waterproof structure.

[0082] Appendix Figure 2Example 1 shows a cross-sectional view of the cable trench and its cover plate AA. The cable trench has a net width of D. The cover plate rests directly on the sidewall of the cable trench via transverse stiffening ribs along its long side. The cantilevered edge of the cover plate is located outside the sidewall, facilitating cable maintenance by lifting the cover plate from the side. A drip groove is provided at the bottom end of the cantilevered edge to prevent rainwater from seeping into the cable trench. Two longitudinal stiffening ribs 4 are provided along the short side of the cover plate, perpendicular to the front transverse stiffening ribs 7 and the rear transverse stiffening ribs 8, but slightly thicker. Together, they form the support system for the cover plate. The outer distance between the two longitudinal stiffening ribs 4 is less than the net width D of the cable trench. During installation, the longitudinal stiffening ribs 4 are engaged with the inner sidewall of the cable trench to prevent the cover plate from sliding to the left and right, acting as beams and allowing for a thinner cover plate. The cover plate is supported on the cable trench wall 2 by the long-side stiffening ribs 7. A drip groove 4 is provided at the bottom of the cantilevered edge 3 to prevent rainwater from seeping in along the edge of the slab. The short side stiffening rib 4 is perpendicular to the front transverse stiffening rib of the long side and is inserted into the inner side of the trench wall to prevent slippage. The size of the stiffening rib is determined based on stress calculations and contains continuous steel bars, replacing the conventional double-layer steel bars.

[0083] Appendix Figure 3 Example 2 shows a cross-sectional view of the cable trench and its cover plate AA. The cable trench has a net width D. The outer distance between the two longitudinal stiffening ribs 4 is greater than the net width D of the cable trench. The two longitudinal stiffening ribs 4 are installed on the upper part of the sidewall of the cable trench. A sealing strip is provided at the bottom of the cover plate body 1 inside the longitudinal stiffening ribs 4. The longitudinal stiffening ribs are installed on the upper part of the sidewall of the cable trench, and a sealing strip is added to the bottom of the cover plate for sealing. This can shorten the length of the cover plate while ensuring waterproof sealing, making it easier to open the cover plate.

[0084] Appendix Figure 4 The longitudinal section along the cable trench shows the cross-section of a cover plate. Two transverse stiffening ribs are provided along the long side of the cover plate: front transverse stiffening rib 7 and rear transverse stiffening rib 8, which are attached to the trench. Figure 2 The two longitudinal stiffening ribs 4 are perpendicular to each other. The slot 5 is cantilevered from the bottom edge of the front transverse stiffening rib 7, and the top surface of the slot 5 is flush with the bottom surface of the slot cover 6, ensuring that the top surface of the entire cover plate remains flat after the slot cover 6 is placed on the slot 5. Figure 4 Display slot 5 is formed by a cantilever structure with stiffening ribs, and the top surface is flat after the slot cover 6 is placed over it. Ultra-high performance concrete is poured in one go, eliminating the need for a frame. During installation, the cover is lightweight and easy to open; maintenance personnel can lift it from the cantilevered side. The snap-fit ​​structure ensures waterproofing and sandproofing at the joint. The two cable trench covers, when joined together, appear as follows: Figure 5 As shown.

[0085] In this embodiment, the cover plate is 20mm thick and suitable for cable trenches with a net width of 1m, at a resistance of 4kN / m. 2 The deformation requirements are met under live load. Other deformations, such as dimensional adjustments or material fine-tuning, are also within the scope of protection of this invention.

[0086] This invention utilizes ultra-high performance, ultra-thin concrete to process cable trench covers, overcoming the following difficulties: (1) Determine a suitable concrete mix proportion; Since concrete with a compressive strength exceeding 100 MPa falls into the category of high-performance concrete, after calculating and determining the strength target, systematic mix proportion tests should be conducted for this type of special concrete to obtain accurate design parameters for key mechanical properties such as compressive and flexural strength.

[0087] (2) Refined design of ultra-thin components; When the thickness of the trench cover is significantly reduced while the functional requirements remain unchanged, all details such as its groove, buckle, limiting structure, anti-slip surface and drainage structure need to be carefully designed to ensure that the full function is achieved within the limited dimensions.

[0088] (3) Crack control of ultra-thin components; Conventional structural members typically rely on reinforcement to control cracks, while ultra-thin members are difficult to reinforce with steel bars and require the addition of steel fibers to enhance crack resistance. The fiber content needs to be determined experimentally to achieve the desired crack control effect.

[0089] (4) Experimental verification stage; Full-scale prototype specimens must be fabricated and static load and impact tests conducted to verify the correctness of the structural analysis results and the reliability of the construction details, while also verifying the effectiveness of the production process and quality control system.

[0090] The difficulty in designing the snap-on cable trench cover of this invention lies essentially in the systemic challenge of applying a cutting-edge composite material to load-bearing structural components. It requires designers to break free from traditional concrete thinking, deeply integrate materials science, structural mechanics, and precision manufacturing processes, and, in the absence of comprehensive specifications, rely on in-depth testing and rigorous analysis to ensure the safety, durability, and reliability of the final product. This is both the difficulty and the source of its technological sophistication and value.

[0091] Scope of Protection of this Invention: The above examples are merely specific embodiments of this invention. Obviously, this invention is not limited to the above embodiments and can have many variations. All variations that can be directly derived or conceived by those skilled in the art from the disclosure of this invention should be considered within the scope of protection of this invention. Other undescribed parts belong to the prior art.

Claims

1. A snap-on cable trench cover, characterized in that, include: The cover plate body (1) has a flat top. A front transverse stiffening rib (7) is provided on the bottom surface of the cover plate body (1). The front transverse stiffening rib (7) is provided along the width direction of the cable trench, and the length of the front transverse stiffening rib (7) is less than the net width of the cable trench. One end of the front transverse stiffening rib (7) extends to the outside of the cover plate body (1) and cantilevered to form a protrusion. The top surface of the protrusion is flush with the bottom surface of the cover plate body (1), and the upper end of the protrusion is provided with a slot (5). The cover plate body (1) has a cantilevered edge (2) along its length direction, the cantilevered edge (2) extends to the outside of the cable trench sidewall, and the length of the cover plate body (1) is greater than the width of the outside of the cable trench. When two cable trench covers are spliced ​​together, one end of one cover overlaps the groove (5) of the other cover to form a closed space.

2. The snap-on cable trench cover according to claim 1, characterized in that: The cover plate body (1) is made of special concrete. The cover plate body (1) is 20mm thick and its weight is more than half that of a conventional 50mm thick cover plate. The special concrete has a compressive strength of not less than 120Mpa and a tensile strength of more than 5 times that of ordinary concrete, and is mixed with steel fibers.

3. A snap-on cable trench cover according to claim 2, characterized in that: It also includes a rear transverse stiffening rib (8), which is arranged on the other side of the bottom surface of the cover plate body (1) along the width direction of the cable trench. The length of the rear transverse stiffening rib (8) is less than the net width of the cable trench.

4. A snap-on cable trench cover according to claim 3, characterized in that: The cover plate body (1) extends to the outer part of the rear transverse stiffening rib (8) to form a slot cover (6). The slot cover (6) cooperates with the slot (5). The length of the slot cover (6) is greater than the length of the slot (5). The bottom surface of the slot cover (6) is flush with the top surface of the slot (5).

5. A snap-on cable trench cover according to claim 4, characterized in that: It also includes two longitudinal stiffening ribs (4), both of which are set at the bottom of the cover body (1) along the length of the cable trench. The two longitudinal stiffening ribs (4) overlap with the front transverse stiffening rib (7) and the rear transverse stiffening rib (8) to form a ring of reinforcing structure at the bottom of the cover body (1).

6. A snap-on cable trench cover according to claim 5, characterized in that: The outer distance between the two longitudinal stiffening ribs (4) is less than the net width of the cable trench, and the two longitudinal stiffening ribs (4) are respectively clamped on the inner side of the side wall of the cable trench.

7. A snap-on cable trench cover according to claim 5, characterized in that: The outer distance between the two longitudinal stiffening ribs (4) is greater than the net width of the cable trench. The two longitudinal stiffening ribs (4) are installed on the upper side wall of the cable trench respectively. A sealing strip is provided at the bottom of the cover body (1) inside the longitudinal stiffening ribs (4).

8. A snap-on cable trench cover according to any one of claims 1 to 7, characterized in that: It also includes a drip groove (3), which is set at the bottom end of the cantilever side (2) of the cover plate body, along the width direction of the cover plate body (1).

9. A design method for a snap-on cable trench cover, characterized in that, Includes the following steps: The design requirements for cable trench covers are as follows: crack width not greater than 0.2mm, deflection not greater than 1 / 200 of the calculated span; The net width and live load requirements of the cable trench were determined, and the thickness of the cover plate body was calculated to be 20mm based on the mechanical properties of the special concrete. Stiffening ribs are provided on all four sides of the bottom surface of the cover plate body, and continuous steel bars are arranged in the stiffening ribs; A slot is provided on the stiffening rib on one side of the long side of the cover plate body, and a slot cover that mates with the slot is provided on the other side. A cantilevered edge and a drip groove are provided on the short side of the cover plate body; The anti-slip pattern on the top surface of the cover plate is made using fair-faced concrete technology. Calculate the design load value, quasi-permanent load value, mid-span strength, mid-span deflection, and mid-span crack respectively to verify whether the design requirements are met.

10. The design method of a snap-on cable trench cover according to claim 9, characterized in that: The specially formulated concrete has a compressive strength of not less than 120 MPa, a tensile strength that is more than 5 times that of ordinary concrete, and is mixed with steel fibers.

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