Flange joint, fabricated steel pipe concrete arch frame and construction method of arch frame

Abstract

The present application relates to the technical field of steel pipe concrete arch flange node connection, and discloses a flange node, an assembled steel pipe concrete arch comprising the flange node and a construction method of the assembled steel pipe concrete arch. The flange node disclosed by the present application comprises: two flange plates, which are respectively used for being connected to the opposite two ends of two adjacent arc segments; two reinforcing members, which are respectively in one-to-one correspondence with the two flange plates and are connected thereto, the opposite two ends of the two adjacent arc segments are both provided with cavities capable of accommodating the reinforcing members, and the two reinforcing members are respectively arranged in the two cavities; first concrete grout, which fills the cavities; and a connecting member, which connects the two flange plates. The flange node provided by the present application is used for connecting the two adjacent arc segments, and can effectively improve the connection strength of the node.

Description

Technical Field

[0001] This invention relates to the field of flange joint connection technology for steel-concrete composite arch frames, and in particular to a flange joint, a steel-concrete composite arch frame, and a construction method for the arch frame. Background Technology

[0002] As mining progresses to deeper levels, the surrounding rock becomes loose and fractured, increasing the difficulty of tunnel support. Traditional U-shaped steel arch frames are insufficient to meet the requirements for controlling surrounding rock deformation. With the same steel content in the cross-section, steel-concrete composite arch frames offer higher support strength and deformation capacity compared to U-shaped steel arch frames, and have become the primary method for surface support in deep surrounding rock deformation.

[0003] Steel-concrete composite arch frames have various cross-sectional forms, each consisting of multiple arc segments. Flange joints are one of the main methods for connecting adjacent arc segments. Existing flange joints consist of two flange plates and multiple bolts. The two flange plates are placed on two separate arc segments and then connected together using connectors to achieve the connection between adjacent arc segments. The most significant drawback of using existing flange joints to connect adjacent arc segments is the low connection strength; the joint is prone to fracture under stress.

[0004] Therefore, how to improve the connection strength of nodes has become an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0005] To solve the above technical problems, the present invention provides a flange node with higher connection strength, an assembled steel pipe arch frame including the flange node, and a construction method for the assembled steel pipe arch frame.

[0006] To achieve the above objectives, the present invention provides the following solution:

[0007] This invention provides a flange node, comprising: two flange plates, each used to connect to opposite ends of two adjacent arc segments; two reinforcing members, each corresponding to and connected to one of the two flange plates, wherein each of the opposite ends of the two adjacent arc segments is provided with a cavity capable of accommodating the reinforcing member, and the two reinforcing members are respectively disposed within the two cavities; a first concrete grout, the first concrete grout filling the cavities; and a connector, the two flange plates being connected via the connector.

[0008] Optionally, the reinforcing member includes an inner steel pipe and a stiffening member. One end of the inner steel pipe is fixedly connected to the flange plate, and the stiffening member is disposed on the outer side wall of the inner steel pipe. The length of the inner steel pipe is shorter than the length of the cavity. The first concrete slurry fills the space between the inner steel pipe and the inner wall of the cavity, as well as the interior of the inner steel pipe.

[0009] Optionally, the stiffening member is a stiffening stud, and there are multiple stiffening members, all of which are evenly arranged on the outer side wall of the inner steel pipe; the connecting member includes a bolt and a nut, one end of the bolt passes through the two flange plates and is fastened by the nut, and there are multiple connecting members, all of which are evenly arranged along the circumference of the flange plates.

[0010] Optionally, the first concrete slurry is composed of at least cement, silica fume, fly ash, slag powder, sand, steel fiber, water-reducing agent and water.

[0011] Optionally, the first concrete slurry, by weight, comprises 600 parts of cement, 150 parts of silica fume, 100 parts of fly ash, 150 parts of slag powder, 1100 parts of sand, 8.8 parts of water-reducing agent, and 176 parts of water, based on the total volume of the cement, silica fume, fly ash, slag powder, sand, and water after uniform mixing. The volumetric content of the steel fiber is 2%. The cement is P.O42.5R silicate cement; the silica fume contains more than 95% silica; the fly ash is Grade I fly ash; the slag powder is S95 grade slag powder; and the sand has a particle size distribution that achieves the most compact packing state. The sand has three particle sizes: coarse sand, medium sand, and fine sand. The coarse sand has a particle size of 0.63mm to 1.25mm, the medium sand has a particle size of 0.315mm to 0.63mm, and the fine sand has a particle size of 0.15mm to 0.63mm. By weight, the coarse sand comprises 425.7 parts, the medium sand 367.4 parts, and the fine sand 306.9 parts. The steel fiber is copper-plated straight steel fiber with a diameter of 0.2mm, a length of 13mm, and a tensile strength of ≥2850MPa. The water-reducing agent is powdered polycarboxylate high-efficiency water-reducing agent or liquid polycarboxylate high-efficiency water-reducing agent with a solid content of 50% and a water reduction rate of ≥40%.

[0012] The present invention also provides a prefabricated steel-concrete composite arch frame, comprising:

[0013] The main body comprises a plurality of arc segments arranged sequentially, and cavities are provided at both ends of any two adjacent arc segments.

[0014] The flange node is provided between any two adjacent arc segments. The two flange plates of the flange node are respectively provided at the opposite ends of the two adjacent arc segments. The two reinforcing members of the flange node are respectively provided in the two cavities provided at the opposite ends of the two adjacent arc segments. The first concrete grout of the flange node fills the cavity, and the two flange plates of the flange node are connected by the connecting member of the flange node.

[0015] Optionally, each of the arc segments is provided with a grouting channel and a grout outlet channel, through which the first concrete grout fills the cavity; all the grouting channels are located on the same side of the main body, all the grout outlet channels are located on the same side of the main body, and the grouting channels and the grout outlet channels are located on different sides of the main body.

[0016] The present invention also provides a construction method for the prefabricated steel-concrete composite arch frame, which includes the following steps when connecting the flange nodes:

[0017] Step 1: Place the two reinforcing members into the two cavities respectively, and connect the two flange plates to the opposite ends of the two arc segments respectively;

[0018] Step two: Connect the two flange plates together using the connector;

[0019] Step 3: Fill both cavities with the first concrete slurry.

[0020] Optionally, the following steps are included before the flange node connection is performed:

[0021] The flange joint is machined to connect the two reinforcing members to the two flange plates respectively;

[0022] The arc segment is processed, the arc segment includes an outer steel pipe and a concrete column disposed inside the outer steel pipe, a second concrete grout is filled inside the outer steel pipe to form the concrete column, and the cavity is formed by making the length of the concrete column shorter than the length of the outer steel pipe.

[0023] Optionally, the flange node and the arc segment can be prefabricated in a factory.

[0024] The present invention achieves the following technical effects compared to the prior art:

[0025] The flange node provided by the present invention includes: two flange plates, which are respectively used to connect to the opposite ends of two adjacent arc segments; two reinforcing members, which correspond to and are connected to the two flange plates one by one, and the opposite ends of the two adjacent arc segments are provided with cavities capable of accommodating the reinforcing members, and the two reinforcing members are respectively disposed in the two cavities; a first concrete grout, which fills the cavities; and a connector, which connects the two flange plates.

[0026] In the specific use of the flange node provided by the present invention, after the two flange plates are butted together, they are mechanically connected by a connector. After the mechanical connection is completed, the first concrete grout is injected into the connection area (cavity) for grouting connection. The flange node provided by the present invention achieves a triple reinforcement effect based on mechanical connection, grouting connection and reinforcement. Compared with only setting flange plates and connectors, the flange node provided by the present invention has higher connection strength. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a cross-sectional view of a flange node provided in an embodiment of the present invention;

[0029] Figure 2 This is an exploded view of the flange node provided in an embodiment of the present invention;

[0030] Figure 3 This is a schematic diagram of the structure of the flange node reinforcement provided in an embodiment of the present invention;

[0031] Figure 4 This is a schematic diagram illustrating the arrangement of the grouting channel and grout outlet channel at the flange node provided in an embodiment of the present invention.

[0032] Figures 1-4 Explanation of reference numerals in the attached drawings: 100, flange node; 1, flange plate; 2, arc segment; 201, concrete column; 202, outer steel pipe; 203, cavity; 3, inner steel pipe; 4, stiffener; 5, connector; 6, grouting channel; 7, grout outlet channel. Detailed Implementation

[0033] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] The purpose of this invention is to provide a flange node with higher connection strength, an assembled steel pipe arch frame including the flange node, and a construction method for the assembled steel pipe arch frame.

[0035] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0036] refer to Figures 1-4 As shown, the flange node 100 provided in this embodiment includes a first concrete grout, a connector 5, two flange plates 1, and two connectors 5. The two flange plates 1 are respectively used to connect to the opposite ends of two adjacent arc segments 2. The two reinforcing members correspond one-to-one with the two flange plates 1. Both opposite ends of the two adjacent arc segments 2 are provided with cavities 203 that can accommodate the reinforcing members. The two reinforcing members are respectively disposed in the two cavities 203. The first concrete grout fills the cavities 203. The two flange plates 1 are connected by connectors 5.

[0037] In the specific use of the flange node 100 provided in this embodiment, after the two flange plates 1 are joined together, they are mechanically connected by the connector 5. After the mechanical connection is completed, the first concrete grout is injected into the connection area (cavity 203) for grouting connection. The flange node 100 provided by the present invention achieves a triple reinforcement effect based on mechanical connection, grouting connection and reinforcement. Compared with only setting flange plates 1 and connector 5, the flange node 100 provided by the present invention has higher connection strength.

[0038] In this embodiment, as Figure 3 As shown, the reinforcing member includes an inner steel pipe 3 and a stiffener 4. One end of the inner steel pipe 3 is fixedly connected to the flange plate 1, and the other end of the inner steel pipe 3 is disposed in the cavity 203. The stiffener 4 is disposed on the outer wall of the inner steel pipe 3. The length of the inner steel pipe 3 is shorter than the length of the cavity 203 so that the first concrete slurry can be injected into the interior of the inner steel pipe 3. The first concrete slurry fills the space between the inner steel pipe 3 and the inner wall of the cavity 203, as well as the interior of the inner steel pipe 3.

[0039] In this embodiment, the stiffening member 4 is a stiffening stud, and there are multiple stiffening members 4. All stiffening members 4 are evenly arranged on the outer side wall of the inner steel pipe 3. For example, multiple stiffening member assemblies are evenly arranged on the outer side wall of the inner steel pipe 3 along the axial direction of the inner steel pipe 3. Each stiffening member assembly includes multiple stiffening members 4 evenly arranged along the circumference of the inner steel pipe 3. The exact number of stiffening members 4 depends on the actual needs. It should be noted that the stiffening member 4 is not limited to stiffening studs, but can also be other structures that can improve the connection strength between the inner steel pipe 3 and the first concrete grout. This is only an example.

[0040] In this embodiment, the connector 5 includes a bolt and a nut. One end of the bolt passes through the two flange plates 1 and is fastened by the nut. There are multiple connectors 5, and all connectors 5 are evenly arranged along the circumference of the flange plates 1. The exact number of connectors 5 depends on the actual needs. Similarly, the connectors 5 are not limited to bolts and nuts; they can also be other forms, as long as they can fix the two flange plates 1 together.

[0041] In this embodiment, the first concrete grout is composed of at least cement, silica fume, fly ash, slag powder, sand, steel fibers, water-reducing agent, and water. The addition of steel fibers significantly improves the strength and toughness of the grouting connection.

[0042] Specifically, in this embodiment, the first concrete slurry, by weight, comprises 600 parts cement, 150 parts silica fume, 100 parts fly ash, 150 parts slag powder, 1100 parts sand, 8.8 parts water-reducing agent, and 176 parts water. The total volume of the cement, silica fume, fly ash, slag powder, sand, and water is used as the base. The volumetric content of steel fiber is 2%. The cement is P.O42.5R silicate cement; the silica fume contains more than 95% silica; the fly ash is Grade I fly ash; the slag powder is S95 grade slag powder; and the sand particle size distribution achieves the most compact packing state, with the sand particle size divided into coarse and fine grades. Three types of sand are used: coarse sand (0.63mm–1.25mm), medium sand (0.315mm–0.63mm), and fine sand (0.15mm–0.63mm). By weight, coarse sand comprises 425.7 parts, medium sand 367.4 parts, and fine sand 306.9 parts. The steel fibers are copper-plated straight fibers with a diameter of 0.2mm and a length of 13mm, possessing a tensile strength of over 2850MPa. The water-reducing agent is either powdered or liquid polycarboxylate high-efficiency water-reducing agent with a solid content of 50% and a water reduction rate of over 40%. This configuration results in good fluidity, compressive strength, and flexural strength in the first concrete slurry. Furthermore, in practical applications, calculations using a modified Andreasen and Andersen packing model are performed to achieve the most compact packing of the sand particle size distribution.

[0043] More specifically, the composition is as follows: 600 parts cement, 150 parts silica fume, 100 parts fly ash, 150 parts slag powder, 1100 parts sand, 8.8 parts water-reducing agent, and 176 parts water. The total volume of the cement, silica fume, fly ash, slag powder, sand, and water is used as the base. The volumetric content of steel fiber is 2%. The cement is P.O42.5R ordinary Portland cement, the silica fume has a silica content of 95.68%, the silica fume is grade 951 produced by Elken International Trading Co., Ltd., the fly ash is grade 1 fly ash, the slag powder is grade S95 slag powder, and the steel fiber is copper-plated straight steel fiber with a diameter of 0. The steel fibers are 2mm thick, 13mm long, and have a tensile strength of 2895MPa. The steel fibers are produced by Yutian County Zhitai Steel Fiber Manufacturing Co., Ltd., and the water-reducing agent is powdered polycarboxylate high-efficiency water-reducing agent. The sand particle size distribution achieves the most compact packing state. The sand particle sizes are divided into three types: coarse sand (0.63mm–1.25mm), medium sand (0.315mm–0.63mm), and fine sand (0.15mm–0.63mm). By weight, the proportions are: coarse sand 425.7 parts, medium sand 367.4 parts, and fine sand 306.9 parts. The first concrete slurry with this mix ratio was subjected to fluidity and mechanical property tests. The test results are as follows:

[0044] (1) The fluidity test of the first concrete slurry with the above proportion was carried out according to the "Method for Determination of Flowability of Cement Mortar" (GB / T2419-2005). The average value of the two mutually perpendicular diameters was 250 mm. The test results showed that the first concrete slurry prepared according to the above proportion had good fluidity.

[0045] (2) Test blocks were made using a 40mm×40mm×160mm mold and cured for 28 days according to the standard curing method. The flexural strength and compressive strength tests were conducted. The average compressive strength of the first concrete slurry was 126MPa and the average flexural strength was 32MPa. The test results show that the first concrete slurry prepared according to the above proportion has good compressive and flexural properties.

[0046] The first concrete slurry mixing method is as follows: First, pour cement, silica fume, fly ash, slag powder, water-reducing agent and sand into the mixer and dry mix for 2 to 3 minutes. Then, slowly add water and mix for 3 to 4 minutes until the slurry has a good flow state. Then, slowly and disperse the steel fiber and mix for 5 minutes.

[0047] refer to Figures 1-4As shown, this embodiment also provides a prefabricated steel-concrete composite arch frame, including: a main body and flange nodes 100. The main body includes multiple arc segments 2 arranged sequentially, the specific number of arc segments 2 being determined according to actual needs, and cavities 203 are provided at opposite ends of any two adjacent arc segments 2. A flange node 100 is provided between any two adjacent arc segments 2, and the two flange plates 1 of the flange node 100 are respectively provided at opposite ends of the two adjacent arc segments 2. The two reinforcing members of the flange node 100 are respectively provided in the two cavities 203 provided at opposite ends of the two adjacent arc segments 2. The first concrete grout of the flange node 100 fills the cavity 203, and the two flange plates 1 of the flange node 100 are connected by the connecting members 5 of the flange node 100.

[0048] In this embodiment, each arc segment 2 is provided with a grouting channel 6 and a grout outlet channel 7. The first concrete grout fills the cavity 203 through the grouting channel 6 and the grout outlet channel 7. One cavity 203 corresponds to one grouting channel 6 and one grout outlet channel 7. The grouting channel 6 and the grout outlet channel 7 are both connected to the cavity 203.

[0049] Furthermore, such as Figure 2 and Figure 4 As shown, all grouting channels 6 are located on the same side of the main body, and all grout outlet channels 7 are located on the same side of the main body, while the grouting channels 6 and grout outlet channels 7 are located on different sides of the main body. This arrangement allows for simultaneous grouting of multiple cavities 203. Specifically, a grouting pipe can be installed, connecting all grouting channels 6 on the main body to this pipe, and the first concrete slurry can be transported to each grouting channel 6 using the grouting pipe.

[0050] The construction method for the prefabricated steel-concrete composite arch frame provided in this embodiment includes the following steps before connecting the flange nodes 100:

[0051] Process flange node 100 to connect two reinforcing members to two flange plates 1 respectively. Specifically, weld multiple stiffening studs to the outside of the inner steel pipe 3 and axially embed the inner steel pipe 3 into the central hole of the flange plate 1. The inner steel pipe 3 and the flange plate 1 are coaxially arranged. The outer diameter of the inner steel pipe 3 is consistent with the diameter of the central hole. Weld the inner steel pipe 3 and the flange plate 1 along the circumferential direction of the central hole to connect the reinforcing member and the flange plate 1 together. More specifically, the distance between the inner steel pipe 3 and the central hole of the flange plate 1 is less than the thickness of the flange plate 1. The remaining distance in the central hole is used to weld the inner steel pipe 3 and the flange plate 1 together along the circumferential direction of the central hole.

[0052] Processing arc segment 2, which includes an outer steel pipe 202 and a concrete column 201 disposed inside the outer steel pipe 202. A second concrete grout is filled inside the outer steel pipe 202 to form the concrete column 201, and a cavity 203 is formed by making the length of the concrete column 201 shorter than the length of the outer steel pipe 202. The detailed composition of the second concrete grout is determined according to actual needs.

[0053] When connecting flange node 100, the following steps are included:

[0054] Step 1: Place the two reinforcing members in the two cavities 203 respectively, and connect the two flange plates 1 to the opposite ends of the two arc segments 2 respectively. Specifically, the axes of the inner steel pipe 3, the outer steel pipe 202 and the cavity 203 are coincident. Place the inner steel pipe 3 coaxially in the cavity 203, so that the end face of the outer steel pipe 202 contacts the flange plate 1. Weld the outer steel pipe 202 and the flange plate 1 in the circumferential direction to realize the connection between the flange plate 1 and the arc segment 2.

[0055] Step 2: Use connector 5 to connect the two flange plates 1 together. Specifically, one of the two flange plates 1 has multiple first threaded holes circumferentially and the other has multiple second threaded holes circumferentially. The positions of the first threaded holes and the second threaded holes correspond one to one. One bolt corresponds to one first threaded hole and one second threaded hole. One end of the bolt passes through the corresponding first threaded hole and second threaded hole and is tightened with a nut to connect the two flange plates 1 together.

[0056] Step 3: Fill both cavities 203 with the first concrete grout. Specifically, fill the space between the inner steel pipe 3 and the inner wall of the cavity 203, as well as the interior of the inner steel pipe 3, with the grouting channel 6 and the grout outlet channel 7.

[0057] In this embodiment, in order to shorten the on-site construction cycle and improve the construction quality, the flange node 100 and the arc segment 2 are prefabricated in the factory, and on-site, the flange node 100 and the arc segment 2 only need to be assembled together.

[0058] This specification uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. Furthermore, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A flange joint, characterized in that, include: Two flange plates, each used to connect to the opposite ends of two adjacent arc segments; Two reinforcing members are provided, each corresponding to and connected to one of the two flange plates. Each of the two adjacent arc segments has a cavity at its opposite ends that can accommodate the reinforcing members. The two reinforcing members are respectively disposed in the two cavities. A first concrete grout, wherein the first concrete grout fills the cavity; A connector, through which the two flange plates are connected; The reinforcing member includes an inner steel pipe and a stiffening member. One end of the inner steel pipe is fixedly connected to the flange plate. The stiffening member is disposed on the outer side wall of the inner steel pipe. The length of the inner steel pipe is shorter than the length of the cavity. The first concrete slurry fills the space between the inner steel pipe and the inner wall of the cavity, as well as the interior of the inner steel pipe.

2. The flange node according to claim 1, characterized in that, The stiffening element is a stiffening stud, and there are multiple stiffening elements, all of which are evenly arranged on the outer side wall of the inner steel pipe; the connecting element includes a bolt and a nut, one end of the bolt passes through the two flange plates and is fastened by the nut, and there are multiple connecting elements, all of which are evenly arranged along the circumference of the flange plates.

3. The flange node according to claim 1, characterized in that, The first concrete slurry is composed of at least cement, silica fume, fly ash, slag powder, sand, steel fiber, water-reducing agent and water.

4. The flange node according to claim 3, characterized in that, The first concrete slurry, by weight, comprises the following components: 600 parts cement, 150 parts silica fume, 100 parts fly ash, 150 parts slag powder, 1100 parts sand, 8.8 parts water-reducing agent, and 176 parts water. The total volume of the cement, silica fume, fly ash, slag powder, sand, and water after thorough mixing is used as the base. The volumetric content of the steel fiber is 2%. The cement is P.O42.5R silicate cement; the silica fume contains more than 95% silica; and the fly ash is Grade I fly ash. The slag powder is S95 grade slag powder; the sand has a particle size distribution that achieves the most compact packing state, and the sand particle size is divided into three types: coarse sand, medium sand, and fine sand. By weight, the coarse sand is 425.7 parts, the medium sand is 367.4 parts, and the fine sand is 306.9 parts; the steel fiber is copper-plated straight steel fiber with a diameter of 0.2 mm, a length of 13 mm, and a tensile strength of ≥2850 MPa; the water-reducing agent is powdered polycarboxylate high-efficiency water-reducing agent or liquid polycarboxylate high-efficiency water-reducing agent with a solid content of 50% and a water reduction rate of ≥40%.

5. A prefabricated steel-concrete composite arch frame, characterized in that, include: The main body comprises a plurality of sequentially arranged arc segments, and cavities are provided at opposite ends of any two adjacent arc segments; as described in any one of claims 1-4, a flange node is provided between any two adjacent arc segments, the two flange plates of the flange node are respectively provided at opposite ends of the two adjacent arc segments, the two reinforcing members of the flange node are respectively provided in the two cavities provided at opposite ends of the two adjacent arc segments, the first concrete grout of the flange node fills the cavities, and the two flange plates of the flange node are connected by the connecting members of the flange node.

6. The prefabricated steel-concrete composite arch frame according to claim 5, characterized in that, Each of the arc segments is provided with a grouting channel and a grout outlet channel. The first concrete grout fills the cavity through the grouting channel and the grout outlet channel. All the grouting channels are located on the same side of the main body, and all the grout outlet channels are located on the same side of the main body. The grouting channels and the grout outlet channels are located on different sides of the main body.

7. A construction method for a prefabricated steel-concrete composite arch frame as described in any one of claims 5-6, characterized in that, The flange node connection includes the following steps: Step 1: Place the two reinforcing members into the two cavities respectively, and connect the two flange plates to the opposite ends of the two arc segments respectively; Step two: Connect the two flange plates together using the connector; Step 3: Fill both cavities with the first concrete slurry.

8. The construction method of the prefabricated steel-concrete composite arch frame according to claim 7, characterized in that, Before performing the flange node connection, the following steps are also included: The flange joint is machined to connect the two reinforcing members to the two flange plates respectively; The arc segment is processed, the arc segment includes an outer steel pipe and a concrete column disposed inside the outer steel pipe, a second concrete grout is filled inside the outer steel pipe to form the concrete column, and the cavity is formed by making the length of the concrete column shorter than the length of the outer steel pipe.

9. The construction method of the prefabricated steel-concrete composite arch frame according to claim 8, characterized in that, The flange joint and the arc segment are manufactured using a factory prefabrication method.

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