Submarine tunnel reinforced concrete lining durability test model and method

Abstract

The invention provides a subsea tunnel reinforced concrete lining durability test model and method.The test model comprises a model frame, a joggle joint end plate, an electric telescopic rod, a threaded rod, a hollow threaded rod, a plugging gasket and a connecting beam, and the model frame comprises a front baffle, a rear baffle, a bottom plate, a first mortise joint end plate, a second mortise joint end plate, the connecting beam and a sliding assembly; the joggle joint end plate is in mortise and tenon connection with the first mortise joint end plate and the second mortise joint end plate, bolt holes are reserved in the joggle joint end plate, the electric telescopic rod is connected with the second mortise joint end plate and controls the second mortise joint end plate to advance or retreat, the threaded rod is used for lifting and fixing reinforcing steel bars, a cavity is formed in the threaded rod, and the thickness and the diameter of the plugging gasket are consistent with those of the joggle joint end plate. And the connecting beam is used for connecting the front baffle plate and the rear baffle plate. According to the invention, the preparation requirements of the durability test sample of the reinforced concrete lining of the subsea tunnel considering different steel bar embedding angles, embedding lengths and embedding depths can be met.

Description

Technical Field

[0001] The invention relates to the technical field of submarine tunnel concrete structure testing, and in particular to a submarine tunnel reinforced concrete lining durability testing model and method. Background Art

[0002] The lining of the submarine tunnel is exposed to long-term erosion from seawater during its service. The steel corrosion caused by chloride ions is an important reason for the degradation of the engineering structure performance. Conducting indoor reinforced concrete durability degradation experiments is of great significance for ensuring the safety of the submarine tunnel structure, optimizing the design and construction, and reducing maintenance costs.

[0003] At present, the reinforced concrete durability test models commonly used are of fixed size. A single model can only prepare test samples of one size. In addition, the arrangement method of steel bars in concrete is limited by the mold, and the positioning accuracy is low, which affects the accuracy of the test results. There is still a lack of undersea tunnel reinforced concrete lining durability test models and precise positioning methods that can consider different steel bar burial angles, burial lengths and burial depths.

[0004] After searching, the Chinese invention patent with application publication number CN108332891A discloses a test mold for reinforced concrete corrosion and a stress monitoring method for the corrosion process. It is provided with a mold groove, a baffle and a steel specimen. The steel specimen is arranged in the cavity of the mold groove, and the two ends of the steel specimen pass through the baffles on both sides. It has the advantages of easy processing and manufacturing, small space occupation and simple preparation. However, the baffle of this patent needs to be opened, and the sealing is poor when laying steel bars with threads on the surface, and the exposed steel bar ends need to be cut off after the concrete specimen is formed, and the positioning and layout of steel bars whose length is less than the side length of the mold cannot be completed. This patent can flexibly arrange steel bars of different orientations and sizes inside the concrete sample, meeting the preparation needs of the durability test samples of the reinforced concrete lining of the submarine tunnel considering different steel bar burial angles, burial lengths and burial depths. Summary of the invention

[0005] In view of the defects in the prior art, the object of the present invention is to provide a durability test model and method for reinforced concrete lining of a submarine tunnel.

[0006] According to one aspect of the present invention, a durability test model for reinforced concrete lining of a submarine tunnel is provided, the model comprising: The model frame includes a front baffle, a rear baffle, a bottom plate, a first mortise-jointed end plate, a second mortise-jointed end plate, a connecting beam, and a sliding assembly; A mortise and tenon end plate, wherein the mortise and tenon end plate is connected to the first mortise and tenon end plate and the second mortise and tenon end plate, and bolt holes are reserved on the mortise and tenon end plate; An electric telescopic rod connected to the second mortise and tenon end plate to control the second mortise and tenon end plate to move forward or backward; A threaded rod passes through the lower bolt hole on the mortise end plate and is used to lift and fix the steel bar; A hollow threaded rod, passing through the upper bolt hole on the mortise end plate, for clamping the steel bar, and having a cavity inside for laying the sensor connection line connected to the steel bar; A plugging gasket, the thickness and diameter of which are consistent with those of the mortise end plate, is used to plug the bolt holes on the mortise end plate; A connecting beam is used to connect the front baffle and the rear baffle.

[0007] Furthermore, there are three bolt holes reserved on the mortise and tenon end plate in each group, which are distributed in an isosceles triangle. The distance from the center of the upper bolt hole to the lower bolt hole is equal to the sum of the radius of the steel bar buried in the test and the radius of the bolt hole. The distance between the two lower bolt holes is smaller than the diameter of the steel bar. The position of the bolt hole on the mortise and tenon end plate is determined according to the position of the steel bar buried in the test design.

[0008] Furthermore, the second mortise and tenon end plate is provided with bolt holes for connecting the sliding assembly.

[0009] Furthermore, the sliding assembly includes screws and U-shaped fasteners. The U-shaped fasteners fit tightly with the top flanges of the front baffle and the rear baffle and can slide freely along the top flanges. Bolt holes are provided on the upper side of the U-shaped fasteners for the screws to pass through, thereby fixing them to the second mortise and tenon end plate.

[0010] Furthermore, a bolt hole is reserved at the lower portion of the U-shaped fastener, and when the second mortise and tenon end plate moves to a preset position, the second mortise and tenon end plate is assisted in being fixed by bolts.

[0011] Furthermore, the rear baffle is marked with lateral distance scale lines and depth scale lines.

[0012] Furthermore, a level bubble for checking the horizontality of the model is provided on the connecting beam.

[0013] According to another aspect of the present invention, a method for testing the durability of reinforced concrete lining of a submarine tunnel is provided. The method is implemented using the above-mentioned test model for the durability of reinforced concrete lining of a submarine tunnel, and comprises: Design the sample size required for the durability test of reinforced concrete lining of submarine tunnels, and determine the length, diameter, burial depth, and front and rear distance of the steel bars according to the test purpose; Put the U-shaped fastener on the top flange of the front baffle and the rear baffle, connect the U-shaped fastener and the second mortise plate with screws, operate the electric telescopic rod, push the second mortise end plate to the specified position along the horizontal distance scale line, and pass the bolts through the bolt holes reserved at the bottom of the U-shaped fastener to ensure that the second mortise end plate is fixed; According to the determined length, diameter, embedding depth, and embedding front and rear distance of the steel bars, select the appropriate mortise and tenon end plates, assemble the mortise and tenon end plates to the first mortise and tenon end plates and the second mortise and tenon end plates one by one, and pass the threaded rods through the lower bolt holes of the mortise and tenon end plates on both sides respectively. The distance between the threaded rods on the left and right sides is less than the length of the steel bars to be embedded; Lay the steel bars on the threaded rods, pass the hollow threaded rods through the upper bolt holes of the tenon-jointed end plates on both sides, adjust the hollow threaded rods, clamp the steel bars to the preset position, and seal the remaining bolt holes of the tenon-jointed end plates on both sides with sealing gaskets; Pour concrete along the depth scale to the preset height, place the model on the vibration table for preliminary vibration, remove the threaded rod and hollow threaded rod, seal the bolt holes with sealing gaskets, pour concrete again, place the model on the vibration table for secondary vibration, scrape off the excess concrete on the surface, and smooth the upper surface of the specimen with a scraper; After the reinforced concrete specimen has formed strength, the electric telescopic rod is operated to take out the reinforced concrete specimen, put it into the curing room for curing, and then conduct a durability test.

[0014] Compared with the prior art, the present invention has at least one of the following beneficial effects: The invention is flexible in operation and can realize the preparation of reinforced concrete durability test samples of different sizes. Rebars of different lengths and diameters can be flexibly arranged inside the concrete sample, meeting the preparation needs of reinforced concrete lining durability test samples of submarine tunnels considering different buried angles, buried lengths and buried depths of the reinforcement. The invention has good sealing performance, effectively avoids the change of the position of the reinforcement during the vibration process, and greatly improves the accuracy of the positioning of the reinforcement inside the concrete. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings: Figure 1 It is a structural schematic diagram of a durability test model of a submarine tunnel reinforced concrete lining according to the present invention; Figure 2 It is a right view of a durability test model of a submarine tunnel reinforced concrete lining according to the present invention; Figure 3 A top view of a durability test model of a submarine tunnel reinforced concrete lining according to the present invention; Figure 4 The schematic diagram of the structure of the mortise and tenon end plate in a durability test model of reinforced concrete lining of a submarine tunnel; Figure 5 This is a schematic diagram of the structure of the sliding component in a durability test model of reinforced concrete lining of an undersea tunnel.

[0016] In the figure: 1-front baffle, 2-rear baffle, 3-bottom plate, 4-first mortise and tenon end plate, 5-second mortise and tenon end plate, 6-connecting beam, 7-tenon and mortise end plate, 8-electric telescopic rod, 9-threaded rod, 10-hollow threaded rod, 11-upper bolt hole, 12-lower bolt hole, 13-rebar, 14-second mortise and tenon end plate bolt hole, 15-screw, 16-U-shaped fastener, 17-top flange, 18-lateral distance scale line, 19-depth scale line, 20-level bubble. DETAILED DESCRIPTION

[0017] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several variations and improvements may be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0018] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this application, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0019] In the present application, terms such as "upper", "lower", "left", "right", "front", "back", "vertical", "horizontal", "side", "bottom", etc. indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings. They are relational words determined only for the convenience of describing the structural relationships of the various parts or elements of the present application, and do not specifically refer to any part or element in the present application and should not be understood as a limitation on the present invention.

[0020] In this application, terms such as "fixed connection", "connected", "connection", etc. should be understood in a broad sense, indicating that it can be fixedly connected, integrally connected or detachably connected; it can be directly connected or indirectly connected through an intermediate medium. Relevant technicians in this field can determine the specific meanings of the above terms in this application according to specific circumstances, and they should not be understood as limitations on this application.

[0021] Reference Figure 1~Figure 5As shown, a durability test model of reinforced concrete lining of a submarine tunnel provided by an embodiment of the present invention includes a model frame, a mortise and tenon end plate 7, an electric telescopic rod 8, a threaded rod 9, a hollow threaded rod 10, a blocking gasket, and a connecting beam 6. Among them, the model frame includes a front baffle 1, a rear baffle 2, a bottom plate 3, a first mortise and tenon end plate 4, a second mortise and tenon end plate 5, a connecting beam 6, and a sliding assembly. The mortise and tenon end plate 7 is mortise-jointed with the first mortise and tenon end plate 4 and the second mortise and tenon end plate 5, and bolt holes are reserved on the mortise and tenon end plate 7.

[0022] An electric telescopic rod 8, connected to the second mortise and tenon end plate 5, controls the second mortise and tenon end plate 5 to move forward or backward; The threaded rod 9 passes through the upper bolt hole 12 on the mortise end plate 7 and is used to lift and fix the steel bar 13; A hollow threaded rod 10 passes through an upper bolt hole 11 on the mortise end plate 7 and is used to clamp the steel bar 13. The hollow threaded rod 10 has a cavity inside for laying a sensor connection line connected to the steel bar 13. A plugging gasket, the thickness and diameter of which are consistent with those of the mortise end plate 7, is used to plug the bolt holes on the mortise end plate 7; A connecting beam 6, used to connect the front baffle 1 and the rear baffle 2; Furthermore, there are three bolt holes reserved on the mortise and tenon end plate 7 in each group, which are distributed in an isosceles triangle. The distance from the center of the upper bolt hole 11 to the lower bolt hole 12 is equal to the sum of the radius of the steel bar 13 buried in the test and the radius of the bolt hole. The distance between the two lower bolt holes is smaller than the diameter of the steel bar 13. The position of the bolt hole on the mortise and tenon end plate 7 is determined according to the position of the steel bar 13 buried in the test design.

[0023] The second mortise and tenon end plate 5 is provided with bolt holes for connecting the sliding assembly.

[0024] The sliding assembly includes screws 15 and U-shaped fasteners 16. The U-shaped fasteners 16 fit tightly with the top flanges 17 of the front baffle 1 and the rear baffle 2 and can slide freely along the top flanges 17. Bolt holes are provided on the upper side of the U-shaped fasteners 16 for the screws 15 to pass through, so as to be fixed to the second mortise and tenon end plate 5.

[0025] Bolt holes are reserved at the lower part of the U-shaped fastener 16. When the second mortise and tenon end plate 5 moves to a preset position, the second mortise and tenon end plate 5 is fixed with the aid of bolts.

[0026] The rear baffle plate 2 is marked with transverse distance scale lines 18 and depth scale lines 19 .

[0027] The connecting beam 6 is provided with a level bubble 20 for checking the horizontality of the model.

[0028] Based on the same inventive concept, another embodiment of the present invention provides a durability test method for reinforced concrete lining of a submarine tunnel. The method is implemented using the above-mentioned durability test model for reinforced concrete lining of a submarine tunnel. Figure 1~Figure 5 , the method comprises the following steps: S1. Design the sample size required for the durability test of reinforced concrete lining of submarine tunnels, and determine the length, diameter, burial depth, and front and rear distance of the steel bars 13 according to the test purpose; S2. Put the U-shaped fastener 16 on the top flange 17 of the front baffle 1 and the rear baffle 2, connect the U-shaped fastener 16 and the second mortise plate with screws 15, operate the electric telescopic rod 8, push the second mortise end plate 5 to the specified position along the horizontal distance scale line 18, and pass the bolts through the bolt holes reserved at the bottom of the U-shaped fastener 16 to ensure that the second mortise end plate 5 is fixed; S3. According to the determined length, diameter, embedding depth, and embedding front and rear distance of the steel bar 13, select the appropriate mortise and tenon end plates 7, assemble the mortise and tenon end plates 7 to the first mortise and tenon end plates 4 and the second mortise and tenon end plates 5 one by one, and pass the threaded rods 9 through the lower bolt holes 12 of the mortise and tenon end plates 7 on both sides, respectively. The distance between the threaded rods 9 on the left and right sides is less than the length of the steel bar 13 to be embedded; S4, placing the steel bar 13 on the threaded rod 9, passing the hollow threaded rod 10 through the upper bolt holes 11 of the mortise and tenon end plates 7 on both sides, adjusting the hollow threaded rod 10, clamping the steel bar 13 to the preset position, and sealing the remaining bolt holes of the mortise and tenon end plates 7 on both sides with sealing gaskets; S5, pour concrete along the depth scale line 19 to a preset height, place the model on a vibration table for preliminary vibration, remove the threaded rod 9 and the hollow threaded rod 10, seal the bolt holes with sealing gaskets, pour concrete again, place the model on the vibration table for secondary vibration, scrape off excess concrete on the surface, and smooth the upper surface of the specimen with a scraper; S6. After the reinforced concrete specimen has formed strength, the electric telescopic rod 8 is operated to take out the reinforced concrete specimen, put it into the curing room for curing, and then conduct a durability test.

[0029] The above-mentioned embodiment of the present invention is flexible in operation, can realize the preparation of reinforced concrete durability test samples of different sizes, can flexibly arrange steel bars of different lengths and diameters inside the concrete sample, and meets the needs of preparing reinforced concrete lining durability test samples of submarine tunnels considering different steel bar burial angles, burial lengths and burial depths. It has good sealing performance, effectively avoids the change of the position of the steel bars during the vibration process, and greatly improves the accuracy of the positioning of the steel bars inside the concrete.

[0030] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various modifications or variations within the scope of the claims, which does not affect the essence of the present invention. The above preferred features can be used in any combination without conflicting with each other.

Claims

1. A durability test model for reinforced concrete lining of a submarine tunnel, characterized in that: include: The model frame includes a front baffle, a rear baffle, a bottom plate, a first mortise-jointed end plate, a second mortise-jointed end plate, a connecting beam, and a sliding assembly; A mortise and tenon end plate, wherein the mortise and tenon end plate is connected to the first mortise and tenon end plate and the second mortise and tenon end plate, and bolt holes are reserved on the mortise and tenon end plate; An electric telescopic rod connected to the second mortise and tenon end plate to control the second mortise and tenon end plate to move forward or backward; A threaded rod passes through the lower bolt hole on the mortise end plate and is used to lift and fix the steel bar; A hollow threaded rod, passing through the upper bolt hole on the mortise end plate, for clamping the steel bar, and having a cavity inside for laying the sensor connection line connected to the steel bar; A plugging gasket, the thickness and diameter of which are consistent with those of the mortise end plate, is used to plug the bolt holes on the mortise end plate; A connecting beam is used to connect the front baffle and the rear baffle.

2. The durability test model of reinforced concrete lining of a submarine tunnel according to claim 1 is characterized in that: There are three bolt holes reserved on the mortise and tenon end plate in each group, which are distributed in an isosceles triangle. The distance from the center of the upper bolt hole to the lower bolt hole is equal to the sum of the radius of the steel bar buried in the test and the radius of the bolt hole. The distance between the two lower bolt holes is less than the diameter of the steel bar. The position of the bolt hole on the mortise and tenon end plate is determined according to the position of the steel bar buried in the test design.

3. The durability test model of reinforced concrete lining of a submarine tunnel according to claim 1 is characterized in that: The second mortise and tenon end plate is provided with bolt holes for connecting the sliding assembly.

4. The durability test model of reinforced concrete lining of a submarine tunnel according to claim 1 is characterized in that: The sliding assembly includes screws and U-shaped fasteners. The U-shaped fasteners fit tightly with the top flanges of the front baffle and the rear baffle and can slide freely along the top flanges. Bolt holes are provided on the upper side of the U-shaped fasteners for the screws to pass through, so as to be fixed to the second mortise and tenon end plate.

5. The durability test model of reinforced concrete lining of a submarine tunnel according to claim 1 is characterized in that: The lower part of the U-shaped fastener is provided with a bolt hole, and when the second mortise and tenon end plate moves to a preset position, the second mortise and tenon end plate is fixed with the aid of bolts.

6. The durability test model of reinforced concrete lining of a submarine tunnel according to claim 1, characterized in that: The rear baffle is marked with transverse distance scale lines and depth scale lines.

7. The durability test model of reinforced concrete lining of a submarine tunnel according to claim 1 is characterized in that: The connecting beam is provided with a level bubble for checking the horizontality of the model.

8. A durability test method for reinforced concrete lining of a submarine tunnel, characterized in that: The durability test model of reinforced concrete lining of a submarine tunnel according to any one of claims 1 to 7 is implemented, comprising: Design the sample size required for the durability test of reinforced concrete lining of submarine tunnels, and determine the length, diameter, burial depth, and front and rear distance of the steel bars according to the test purpose; Put the U-shaped fastener on the top flange of the front baffle and the rear baffle, connect the U-shaped fastener and the second mortise plate with screws, operate the electric telescopic rod, push the second mortise end plate to the specified position along the horizontal distance scale line, and pass the bolts through the bolt holes reserved at the bottom of the U-shaped fastener to ensure that the second mortise end plate is fixed; According to the determined length, diameter, embedding depth, and embedding front and rear distance of the steel bars, select the appropriate mortise and tenon end plates, assemble the mortise and tenon end plates to the first mortise and tenon end plates and the second mortise and tenon end plates one by one, and pass the threaded rods through the lower bolt holes of the mortise and tenon end plates on both sides respectively. The distance between the threaded rods on the left and right sides is less than the length of the steel bars to be embedded; Lay the steel bars on the threaded rods, pass the hollow threaded rods through the upper bolt holes of the tenon-jointed end plates on both sides, adjust the hollow threaded rods, clamp the steel bars to the preset position, and seal the remaining bolt holes of the tenon-jointed end plates on both sides with sealing gaskets; Pour concrete along the depth scale to the preset height, place the model on the vibration table for preliminary vibration, remove the threaded rod and hollow threaded rod, seal the bolt holes with sealing gaskets, pour concrete again, place the model on the vibration table for secondary vibration, scrape off the excess concrete on the surface, and smooth the upper surface of the specimen with a scraper; After the reinforced concrete specimen has formed strength, the electric telescopic rod is operated to take out the reinforced concrete specimen, put it into the curing room for curing, and then conduct a durability test.

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