A uHPC manhole cover and a production process thereof

Abstract

The application discloses a UHPC inspection well lid and a production process thereof, wherein iron sand is added into a UHPC concrete formula to replace part of traditional fine quartz sand, the strength and compression resistance of the iron sand are superior to those of the fine quartz sand, so that the overall strength and compression resistance of the UHPC concrete are improved, the performance is further enhanced by steel fibers, the UHPC concrete is poured into an outer shell of the inspection well lid to replace a traditional iron or plastic inspection well lid, the cost is reduced, the strength of the inspection well lid is ensured, production is more convenient, direct pouring is directly used, demolding is not needed, the iron content is small, and the risk of theft is reduced, a plurality of reinforcing ribs are arranged on an outer wall of the main shell in the application, the overall strength of the main shell is improved, the load-bearing performance is improved, the reinforcing ribs are extended into a filling cavity, and a first steel mesh is directly welded on the reinforcing ribs, so that the integrity between the first steel mesh and the main shell is improved, and the strength is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of inspection well covers, in particular to the technical field of UHPC inspection well covers and production processes thereof. BACKGROUND

[0002] With the development of modern cities, the urban underground pipeline system is becoming more and more developed. There are a large number of underground pipelines in urban construction, such as sewers, underground gas pipelines, water pipelines, power pipelines, communication pipelines, and national defense pipelines. These pipelines have an outlet to the ground every certain distance, which is called a manhole. The manhole opening is usually flush with the ground, so a cover is needed to cover the manhole. The cover is called a manhole cover. Manhole covers are usually made of reinforced concrete, metal, and reinforced plastic. The shapes are mainly round and square. On the manhole cover, the purpose of the underground pipeline, the pipeline maintenance unit, and the telephone number are usually indicated.

[0003] There are many types of existing manhole covers. For example, a cast manhole cover is disclosed in Chinese patent CN105275017A. The manhole cover body is a cast iron part. The upper surface of the manhole cover body is an oval structure. The length of the manhole cover is twice the width. The length of the manhole cover is 80-100 cm, the width is 50-60 cm, and the thickness is 3-5 cm. The manhole cover has a reinforcing rib in the width direction.

[0004] Chinese patent CN101424084B discloses a nodular cast iron composite manhole cover. The manhole cover body includes a nodular cast iron frame and an unsaturated resin covering layer fixed to the nodular cast iron frame. The nodular cast iron frame includes a frame disc with multiple unsaturated resin filling holes. The bottom surface of the frame disc is fixedly provided with a vertical frame. The vertical frame and the outer edge of the frame disc form a fixed step. The frame disc is fixedly provided with a reinforcing rib on the bottom surface of the inner side of the vertical frame. The frame disc, vertical frame, and reinforcing rib are integrally cast and formed into a nodular cast iron frame.

[0005] However, the above-mentioned manhole covers are almost made of cast iron, which has a relatively high cost. Since the value of renewable utilization is high, the phenomenon of losing manhole covers often occurs, which causes hidden dangers to society and traffic safety. Therefore, it is necessary to further develop new types of manhole covers that replace traditional cast iron manhole covers while maintaining the basic shape and performance of the manhole covers. SUMMARY

[0006] The UHPC inspection well cover and the production process thereof disclosed by the application have the advantages that the UHPC concrete with a lower cost is combined with the inspection well cover shell to replace the traditional cast iron inspection well cover, the renewable value of the inspection well cover is reduced, and the anti-theft performance is improved.

[0007] To achieve the above object, the application provides a UHPC inspection well cover, which comprises an inspection well cover shell and UHPC concrete filled in the inspection well cover shell, and the UHPC concrete is made of the following key parts of raw materials: 1000 parts of Portland cement, 150-200 parts of silica fume, 50-150 parts of steel fiber, 250-450 parts of iron sand, 550-750 parts of fine quartz sand, 20-30 parts of water reducing agent and 400-500 parts of water.

[0008] The inspection well cover shell comprises a main shell in a disc shape and an upper cover, the main shell is provided with a filling cavity, the UHPC concrete is filled in the filling cavity, the upper cover is detachably connected with the upper side opening of the filling cavity, the middle part of the main shell is provided with a downwardly protruding lower protruding part, the center of the lower protruding part is provided with a pouring opening in communication with the filling cavity, the circumferential surface of the lower protruding part is provided with a conical surface transition section integrally formed with the main shell, the outer wall of the conical surface transition section is provided with a plurality of reinforcing ribs, one end of each of the reinforcing ribs away from the lower protruding part extends through the outer wall of the conical surface transition section to the filling cavity, and the filling cavity is provided with a horizontally arranged first steel mesh, and the outer periphery of the first steel mesh is welded with the reinforcing ribs extending into the filling cavity.

[0009] Preferably, the reinforcing ribs are equidistantly arranged around the outer wall of the conical surface transition section, and a horizontal rib is arranged between adjacent reinforcing ribs.

[0010] Preferably, the lower end surface of the upper cover is provided with a plurality of downwardly protruding lower anchoring members, the lower anchoring members extend into the filling cavity, and the lower anchoring members are in a J shape or an inverted T shape.

[0011] Preferably, the conical surface transition section is provided with a plurality of exhaust holes in communication with the filling cavity.

[0012] Preferably, one end of the filling cavity close to the pouring opening is provided with a second steel mesh, the second steel mesh is welded with the inner wall of the pouring opening, and the welding points of the second steel mesh and the inner wall of the pouring opening correspond to the positions of the reinforcing ribs.

[0013] Preferably, the center of the second steel mesh is provided with a through hole for a vibrator to pass through.

[0014] Preferably, the main shell is made of iron or steel, and the upper cover is made of PE or PP, PA or resin material.

[0015] Preferably, the steel fiber is a copper-plated corrugated steel fiber with a diameter of 0.3mm-0.15mm and a length of 30mm-80mm; the iron sand and the fine quartz sand have a particle size of less than 0.5mm.

[0016] Preferably, the lower convex column protruding downward is arranged at the lower end of the upper cover, a convex hollow cavity is arranged in the lower convex column and penetrates the upper and lower ends of the lower convex column, a convex column hole corresponding to the lower convex column is arranged on the main shell for the lower convex column to pass through, and a plurality of positioning recesses and positioning protrusions corresponding to each other are arranged at the connecting position of the upper cover and the main shell.

[0017] Another object of the present application is to provide a UHPC inspection well cover production process, comprising the following steps:

[0018] Step S1, preparing the inspection well cover outer shell as described in any one of the above, and buckling the upper cover and the main shell;

[0019] Step S2, weighing and taking silicate cement 1000 parts, silica fume 150-200 parts, steel fiber 50-150 parts, iron sand 250-450 parts, fine quartz sand 550-750 parts, water reducing agent 20-30 parts, and water 400-500 parts according to the weight ratio;

[0020] Step S3, mixing and dry mixing the silicate cement 1000 parts, silica fume 150-200 parts, steel fiber 50-150 parts, iron sand 250-450 parts, fine quartz sand 550-750 parts, and water reducing agent 20-30 parts, and then adding water 400-500 parts to wet mix to obtain UHPC concrete;

[0021] Step S4, inverting the inspection well cover outer shell prepared in step one so that the pouring opening faces upward, and pouring the UHPC concrete prepared in step S3 into the filling cavity through the pouring opening;

[0022] Step S5, inserting a vibrator into the filling cavity through the pouring opening for vibration, and the vibration time is 1-10min until the concrete is exposed from each exhaust hole;

[0023] Step S6, supplementing the UHPC concrete into the filling cavity through the pouring opening again, and inserting the vibrator into the filling cavity for secondary vibration, and the vibration time is 20-60s; if the UHPC concrete is insufficient during the vibration process, continue to supplement the UHPC concrete into the filling cavity through the pouring opening;

[0024] Step S7, take out the vibrator, smooth the UHPC concrete at the pouring opening, start watering and curing after the UHPC concrete coagulates, the watering interval is controlled at 4-6h in the environment above 30 degrees Celsius; the watering interval is 6-10h in the environment of 15-30 degrees Celsius; the watering interval is 8-12h below 5-15 degrees Celsius.

[0025] The UHPC inspection well cover and the production process have the beneficial effects that: the iron sand is added in the UHPC concrete formula to replace part of the traditional fine quartz sand, the strength and the compression resistance of the iron sand are better than those of the fine quartz sand, so that the overall strength and the compression resistance of the UHPC concrete are improved, the steel fiber further enhances the performance, the UHPC concrete is poured into the shell of the inspection well cover to replace the traditional iron or plastic well cover, the cost is reduced, the strength of the inspection well cover is ensured, the production is more convenient, direct pouring is used, demolding is not needed, the iron content is small, and the risk of theft is reduced, the outer wall of the main shell is provided with multiple reinforcing ribs in the application, the overall strength of the main shell is improved, the load-bearing performance is improved, the reinforcing ribs are extended into the filling cavity, and the first steel mesh is directly welded on the reinforcing ribs, so that the integrity between the first steel mesh and the main shell is improved, the strength is improved, the first steel mesh and the main shell are matched with each other, the load-bearing and deformation resistance of the inspection well cover are improved, and the pouring stability of the UHPC concrete is improved.

[0026] The features and advantages of the present application will be described in detail with examples combined with the drawings. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 is a schematic view of the front structure of the shell of the inspection well cover in the application.

[0028] Figure 2 is a schematic view of the front structure of the shell of the inspection well cover in the application.

[0029] Figure 3 is a schematic view of the lower structure of the shell of the inspection well cover in the application.

[0030] Figure 4 is a schematic view of the top structure of the shell of the inspection well cover in the application.

[0031] Wherein:

[0032] 1, the shell of the inspection well cover; 2, the first steel mesh; 3, the second steel mesh; 11, the main shell; 12, the upper cover; 13, the reinforcing rib; 14, the horizontal rib; 111, the filling cavity; 112, the lower convex part; 113, the conical transition section; 114, the convex column hole; 115, the positioning protrusion; 121, the exhaust hole; 122, the convex column; 123, the positioning groove; 1516 1121, the pouring opening; 1131, the exhaust hole; 1221, the convex column hollow cavity. DETAILED DESCRIPTION

[0033] In order to make the objects, technical solutions and advantages of the present application clearer, the following further describes the present application with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not used to limit the scope of the present application. In addition, in the following description, the description of well-known structures and techniques is omitted to avoid unnecessary confusion of the concept of the present application.

[0034] In the description of the present application, it should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0035] In the description of the present application, it should be noted that the terms "center", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the present application is usually placed, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", "third", and the like are only used to distinguish the description and cannot be understood as indicating or implying relative importance. Therefore, the features defined as "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, "a plurality of" means two or more, unless otherwise explicitly specified and limited. "Several" means one or more, unless otherwise explicitly specified and limited.

[0036] In the description of the present application, it should also be noted that unless otherwise explicitly specified and limited, the terms "disposed", "mounted", "connected", "linked" should be broadly understood, for example, can be fixedly connected, can be detachably connected, or integrally connected; can be mechanically connected, can be electrically connected; can be directly connected, can be indirectly connected through an intermediate medium, and can be internal communication of two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances. Example 1

[0037] Reference is made to Figure 1 , Figure 2 , Figure 3 and Figure 4The application discloses a UHPC manhole cover, which comprises a manhole cover shell body 1 and UHPC concrete filled in the manhole cover shell body 1, wherein the UHPC concrete is made of the following key parts of raw materials: 1000 parts of Portland cement, 175 parts of silica fume, 100 parts of steel fiber, 350 parts of iron sand, 600 parts of fine quartz sand, 25 parts of water reducing agent and 450 parts of water. In the UHPC concrete formula, the iron sand is added to replace part of the traditional fine quartz sand, and the strength and compression resistance of the iron sand are better than those of the fine quartz sand, so that the overall strength and compression resistance of the UHPC concrete are improved, and the performance is further enhanced by the steel fiber.

[0038] The manhole cover shell body 1 comprises a disc-shaped main shell body 11 and an upper cover 12, the main shell body 11 is internally provided with a filling cavity 111, the UHPC concrete is filled in the filling cavity 111, the upper cover 12 is detachably connected with the upper side opening of the filling cavity 111, the middle part of the main shell body 111 is provided with a downwardly protruding lower protruding part 112, the center of the lower protruding part 112 is provided with a pouring opening 1121 which is in communication with the filling cavity 111, the circumferential surface of the lower protruding part 112 is provided with a conical surface transition section 113 which is integrally formed with the main shell body 11, the outer wall of the conical surface transition section 113 is provided with a plurality of reinforcing ribs 13, one end of each of the reinforcing ribs 13 which is away from the lower protruding part 112 extends through the outer wall of the conical surface transition section 113 and reaches into the filling cavity 111, the filling cavity 111 is internally provided with a horizontally arranged first steel mesh 2, and the outer periphery of the first steel mesh 2 is welded and connected with the reinforcing ribs 13 which extend into the filling cavity 111. In the embodiment, the UHPC concrete is poured into the manhole cover shell body 1 to replace the traditional iron or plastic manhole cover, so that the cost can be reduced, the strength of the manhole cover can be ensured, the production is more convenient, the pouring can be directly performed, demolding is not needed, the iron content is small, and the risk of theft is reduced. In the application, the outer wall of the main shell body 11 is provided with a plurality of reinforcing ribs 13, so that the overall strength of the main shell body 11 can be improved and the load-bearing performance can be improved. The reinforcing ribs 13 extend into the filling cavity 111, and the first steel mesh 2 is directly welded on the reinforcing ribs 13, so that the integrity between the first steel mesh 2 and the main shell body 11 can be improved, the strength can be improved, the first steel mesh 2 and the main shell body 11 are matched with each other, the load-bearing and deformation resistance performance of the manhole cover is improved, and the pouring stability of the UHPC concrete is improved.

[0039] Referring to Figure 1 , Figure 3 The reinforcing ribs 13 are equidistantly arranged around the outer wall of the conical surface transition section 113, and a horizontal rib 14 is arranged between adjacent reinforcing ribs 13. The horizontal rib 14 further improves the strength and prevents the reinforcing ribs 13 from being deformed.

[0040] Referring to Figure 2The lower end surface of the upper cover 12 is provided with a plurality of protruding lower anchoring members 121 extending into the filling cavity 111, and the lower anchoring members 121 are inverted T-shaped. During pouring, the lower anchoring members 121 can be poured into the UHPC concrete, thereby firmly fixing the upper cover 12 and the main shell 11 together.

[0041] Referring to Figure 3 The conical transition section 113 is provided with a plurality of exhaust holes 1131 communicating with the filling cavity 111. The exhaust holes 1131 mainly serve two purposes: one is to exhaust air in the filling cavity 111 during pouring, and the other is to allow workers to observe the internal pouring condition, and to determine whether the concrete at the position is poured in place by observing whether the concrete overflows from the exhaust holes 1131.

[0042] Referring to Figure 2 One end of the filling cavity 111 close to the pouring opening 1121 is provided with a second steel mesh 3, which is welded to the inner wall of the pouring opening 1121, and the welding points of the second steel mesh 3 and the inner wall of the pouring opening 1121 correspond to the positions of the reinforcing ribs 13. The first steel mesh 2 and the second steel mesh 3 correspond to the upper and lower ends of the reinforcing ribs 13, respectively, further improving the integrity, strength and anti-deformation performance between the steel mesh and the main shell 11.

[0043] Preferably, the second steel mesh 3 is provided with a through hole for the vibrator to pass through. This facilitates vibration during pouring, thereby improving the uniformity of the concrete.

[0044] Preferably, the main shell 11 is made of iron, and the upper cover 12 is made of resin. The main shell 11 is subjected to a large force during use, and is made of iron to ensure strength, while the upper cover 12 is exposed and is made of resin or other materials with low recycling value, which is conducive to improving the anti-theft performance.

[0045] Preferably, the steel fiber is a copper-plated corrugated steel fiber with a diameter of 0.3mm and a length of 80mm; and the iron sand and the fine quartz sand have a particle size of less than 0.5mm.

[0046] Referring to Figure 2The lower convex column 122 is provided on the lower end of the upper cover 12 and protrudes downward, and a convex column hollow cavity 1221 is arranged in the lower convex column 122 and penetrates the upper and lower ends of the lower convex column 122. The main shell 11 is provided with a convex column hole 114 corresponding to the lower convex column 122 for the lower convex column 122 to pass through. The connecting position of the upper cover 12 and the main shell 11 is also respectively provided with a plurality of corresponding positioning grooves 123 and positioning protrusions 115. The convex column hollow cavity 122 inside the lower convex column is used for the water flow on the upper side of the well cover to flow into the well during use, and is also used for the well cover hook to extend in to lift the well cover. The positioning grooves 123 and the positioning protrusions 115 are matched with each other to facilitate positioning and connection. Embodiment two

[0047] On the basis of embodiment one, the difference between this embodiment and embodiment one is that the UHPC concrete is made of the following key parts of raw materials: 1000 parts of Portland cement, 150 parts of silica fume, 50 parts of steel fiber, 250 parts of iron sand, 550 parts of fine quartz sand, 20 parts of water reducing agent, and 400 parts of water. The specific gravity of the Portland cement in this embodiment is higher, and the strength is higher. Embodiment three

[0048] On the basis of embodiment one, the difference between this embodiment and embodiment one is that the UHPC concrete is made of the following key parts of raw materials: 1000 parts of Portland cement, 150 parts of silica fume, 50 parts of steel fiber, 250 parts of iron sand, 550 parts of fine quartz sand, 20 parts of water reducing agent, and 400 parts of water. The specific gravity of the Portland cement in this embodiment is higher, and the strength is higher. Embodiment four

[0049] This embodiment proposes a UHPC well cover production process, which includes the following steps:

[0050] Step S1, prepare the well cover outer shell 1 as described in any one of embodiments 1-3, and buckle the upper cover 12 and the main shell 11;

[0051] Step S2, weigh and take Portland cement, silica fume, steel fiber, iron sand, fine quartz sand, water reducing agent, and water according to the weight ratio;

[0052] Step S3, mix the Portland cement, silica fume, steel fiber, iron sand, fine quartz sand, and water reducing agent for dry mixing, and then add water for wet mixing to obtain UHPC concrete;

[0053] Step S4, invert the well cover outer shell 1 prepared in step one so that the pouring port 1121 faces upward, and pour the UHPC concrete prepared in step S3 into the filling cavity 111 through the pouring port 1121;

[0054] Step S5, the vibrator is inserted into the filling cavity 111 through the pouring opening 1121 to vibrate, the vibration time is 5 min, until the concrete is exposed from each exhaust hole 1131;

[0055] Step S6, the UHPC concrete is added into the filling cavity 111 through the pouring opening 1121 again, and the vibrator is inserted into the filling cavity 111 to vibrate for 20-60 s, if the UHPC concrete is insufficient during the vibration, the UHPC concrete is continuously added into the filling cavity 111 through the pouring opening 1121;

[0056] Step S7, the vibrator is taken out, the UHPC concrete at the pouring opening 1121 is smoothed, and the UHPC concrete is poured and maintained after the UHPC concrete is coagulated, the pouring interval is controlled to be 5 h in an environment above 30 degrees Celsius, the pouring interval is 8 h in an environment of 15-30 degrees Celsius, and the pouring interval is 10 h in an environment below 5-15 degrees Celsius. In the embodiment, the UHPC concrete is dry mixed in step S3 and then wet mixed in step S4, the secondary mixing is more uniform, the concrete is vibrated and added multiple times, the internal gap is reduced, and the strength is improved.

[0057] The standard parts used in the application file can be purchased from the market, the specific connection mode of each part adopts the conventional means such as bolts, rivets and welding in the prior art, the internal components of the electric sliding rail sliding seat, the cylinder, the welding machine, the electric telescopic rod and the controller adopt conventional models in the prior art, and the internal structure belongs to the prior art structure, workers can complete normal operation according to the prior art manual, and the circuit connection adopts the conventional connection mode in the prior art, which will not be described in detail here.

[0058] It should be noted that although the above embodiments have been described in the present text, the patent protection scope of the present application is not limited thereby. Therefore, based on the innovative idea of the present application, the changes and modifications of the embodiments described in the present text, or the equivalent structure or equivalent process transformation made by using the content of the present application specification and drawings, directly or indirectly apply the above technical solutions to other related technical fields, are all included in the protection scope of the present application patent.

Claims

1. A UHPC manhole cover, comprising a manhole cover outer shell (1) and a UHPC concrete filled in the manhole cover outer shell (1), characterized in that: The UHPC concrete is made of raw materials in the following key proportions: Portland cement 1000 parts, silica fume 150-200 parts, steel fiber 50-150 parts, iron sand 250-450 parts, fine quartz sand 550-750 parts, water reducing agent 20-30 parts, and water 400-500 parts; The outer shell body (1) comprises a disc-shaped main shell body (11) and an upper cover (12), the main shell body (11) is provided with a filling cavity (111) therein, the UHPC concrete is filled in the filling cavity (111), the upper cover (12) is detachably connected with the upper side opening of the filling cavity (111), the middle part of the main shell body (11) is provided with a downwardly protruding lower protruding part (112), the center of the lower protruding part (112) is provided with a pouring opening (1121) in communication with the filling cavity (111), the circumferential surface of the lower protruding part (112) is provided with a conical transition section (113) integrally formed with the main shell body (11), the outer wall of the conical transition section (113) is provided with a plurality of reinforcing ribs (13), one end of each reinforcing rib (13) away from the lower protruding part (112) extends through the outer wall of the conical transition section (113) and into the filling cavity (111), the filling cavity (111) is provided with a horizontally arranged first steel mesh (2), the outer periphery of the first steel mesh (2) is weldedly connected with the reinforcing ribs (13) extending into the filling cavity (111); the reinforcing ribs (13) are equidistantly arranged around the outer wall of the conical transition section (113), and a horizontal rib (14) is arranged between adjacent reinforcing ribs (13); the lower end surface of the upper cover (12) is provided with a plurality of downwardly protruding lower anchoring members (121), the lower anchoring members (121) extend into the filling cavity (111), and the lower anchoring members (121) are in J-shaped or inverted T-shaped; the conical transition section (113) is provided with a plurality of exhaust holes (1131) in communication with the filling cavity (111); one end of the filling cavity (111) close to the pouring opening (1121) is provided with a second steel mesh (3), the second steel mesh (3) is weldedly connected with the inner wall of the pouring opening (1121), and the welding points of the second steel mesh (3) and the inner wall of the pouring opening (1121) correspond to the positions of the reinforcing ribs (13); the center of the second steel mesh (3) is provided with a through hole for a vibrator.

2. A UHPC manhole cover according to claim 1, characterized in that: The main shell body (11) is made of iron or steel, and the upper cover (12) is made of PE or PP, PA, or resin material.

3. A UHPC manhole cover as claimed in claim 1, characterized in that: The steel fiber is a copper-plated corrugated steel fiber with a diameter of 0.3-0.15 mm and a length of 30-80 mm; the iron sand and the fine quartz sand have a particle size of less than 0.5 mm.

4. A UHPC manhole cover as claimed in claim 1, characterized in that: The upper cover (12) is provided with a lower convex column (122) protruding downward at the lower end, a hollow cavity (1221) is arranged in the lower convex column (122) and penetrates the upper and lower ends of the lower convex column (122), the main shell (11) is provided with a convex column hole (114) corresponding to the lower convex column (122) for the passage of the lower convex column (122), and the connecting position of the upper cover (12) and the main shell (11) is further provided with a plurality of corresponding positioning grooves (123) and positioning protrusions (115), respectively.

5. A process for the production of a UHPC manhole cover, characterized in that, The method comprises the following steps: Step S1, preparing the manhole cover outer shell (1) according to any one of claims 1-4, and buckling the upper cover (12) and the main shell (11); Step S2, weighing and taking silicate cement 1000 parts, silica fume 150-200 parts, steel fiber 50-150 parts, iron sand 250-450 parts, fine quartz sand 550-750 parts, water reducing agent 20-30 parts, and water 400-500 parts according to the weight ratio; Step S3, mixing and dry mixing silicate cement 1000 parts, silica fume 150-200 parts, steel fiber 50-150 parts, iron sand 250-450 parts, fine quartz sand 550-750 parts, and water reducing agent 20-30 parts, and then adding water 400-500 parts for wet mixing to obtain UHPC concrete; Step S4, inverting the manhole cover outer shell (1) prepared in step one so that the pouring port (1121) faces upward, and injecting the UHPC concrete prepared in step S3 into the filling cavity (111) through the pouring port (1121); Step S5, inserting a vibrator into the filling cavity (111) through the pouring port (1121) for vibration, and the vibration time is 1-10 min; Step S6, supplementing the UHPC concrete into the filling cavity (111) through the pouring port (1121) again, and inserting a vibrator into the filling cavity (111) for secondary vibration, and the vibration time is 20-60 s; if the UHPC concrete is insufficient during the vibration process, continue to supplement the UHPC concrete into the filling cavity (111) through the pouring port (1121); Step S7, removing the vibrator, smoothing the UHPC concrete at the pouring port (1121), and starting water curing after the UHPC concrete is coagulated; the water interval is controlled to be 4-6 h in an environment above 30 degrees Celsius; the water interval is 6-10 h in an environment of 15-30 degrees Celsius; and the water interval is 8-12 h in an environment below 5-15 degrees Celsius.

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