A construction joint water stop and concrete bonding fatigue test device

Abstract

The application relates to the technical field of construction material fatigue testing, and proposes a construction joint water stop belt and concrete bonding fatigue test device, a machine base, a concrete block fixing table and a multidirectional fatigue test mechanism are arranged on the upper surface of the machine base, a liftable freezing and thawing mechanism is arranged directly above the concrete block fixing table, the liftable freezing and thawing mechanism is connected with the machine base through a support, and a liquid spraying mechanism is arranged on one side of the liftable freezing and thawing mechanism. Through the arrangement of the multidirectional fatigue test mechanism, the single-direction static test in the traditional water stop belt bonding strength test is changed; through the multidirectional reciprocating movement of the multidirectional fatigue test mechanism, the expansion and contraction changes of the construction joint in different directions under the real environment are simulated; meanwhile, the liftable freezing and thawing mechanism and the liquid spraying mechanism are designed to simulate different tunnel environments to carry out freezing and thawing cycles, chemical corrosion and other operations, simulate extreme working conditions of multi-field coupling, and evaluate the long-term durability of the bonding position of the water stop belt and the concrete.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of construction material fatigue testing, in particular to a construction joint water stop belt and concrete bonding fatigue test device. BACKGROUND

[0002] In tunnel engineering, waterproof construction is the most important part of engineering quality, and the bonding construction of water stop belt and concrete at the construction joint is the key link to ensure the waterproof effect of the tunnel structure, so the bonding effect between the water stop belt and the concrete needs to be tested before construction. The traditional water stop belt bonding strength test has the following shortcomings:

[0003] 1. Only static tensile / shear strength is considered, and the influence of long-term fatigue load on the bonding performance of the concrete interface is not considered;

[0004] 2. Since the changes at the construction joint are not in a single direction, a single direction of fatigue testing cannot meet the needs of the actual environment;

[0005] 3. Since different geological tunnel environments are different, the existing bonding degree test device cannot be simulated according to different geological tunnel environments, which can easily lead to large deviations between experiments and reality.

[0006] Therefore, in view of the above problems, a construction joint water stop belt and concrete bonding fatigue test device is proposed to solve the above problems. SUMMARY

[0007] To achieve the above purpose, the present application realizes the following technical scheme: a construction joint water stop belt and concrete bonding fatigue test device, a machine base, a concrete block fixing table and a multidirectional fatigue test mechanism are arranged on the upper surface of the machine base, a liftable freeze-thaw mechanism is arranged directly above the concrete block fixing table, the liftable freeze-thaw mechanism is connected with the machine base through a support, and a liquid spraying mechanism is arranged on one side of the liftable freeze-thaw mechanism.

[0008] The multidirectional fatigue test mechanism includes a clamping assembly, a horizontal and vertical movement assembly, a reciprocating stretching assembly and a driving assembly, the clamping assembly is used to fix the water stop belt bonded with the concrete block, the horizontal and vertical movement assembly and the reciprocating stretching assembly are used to drive the water stop belt to perform multidirectional fatigue testing, and the driving assembly is used to drive the horizontal and vertical movement assembly and the reciprocating stretching assembly to move.

[0009] The liquid spraying mechanism includes a water flow spraying head and an erosion liquid spraying head, which are used to spray liquid to the bonding part of the concrete block and the water stop belt, and the water flow spraying head and the erosion liquid spraying head are connected through a switching assembly.

[0010] Preferably, the surface of the base is slidably connected with a side plate frame, the horizontal and vertical moving assembly is located at one side of the side plate frame, the horizontal and vertical moving assembly comprises a fixed frame fixed on the surface of the side plate frame, a horizontal moving frame is slidably connected in the fixed frame, a vertical moving frame is slidably connected in the horizontal moving frame, a triangular cam is arranged in the vertical moving frame, and the shaft of the triangular cam is connected with the driving assembly.

[0011] Preferably, the surface of the vertical moving frame is fixed with a connecting rod, and the clamping assembly is mounted on the outer surface of the connecting rod.

[0012] Preferably, the reciprocating stretching assembly comprises a rotating rod, the rotating rod is rotatably connected with a supporting block fixed on the surface of the side plate frame, an eccentric disc is fixed at the bottom of the rotating rod, a connecting rod is rotatably connected with the surface of the eccentric disc, a supporting table is arranged on one side of the connecting rod, and the connecting rod is rotatably connected with a fixed rod on the surface of the supporting table.

[0013] Preferably, the driving assembly comprises a driving motor fixed on the surface of the supporting table, the surface of the side plate frame is fixed with a double-shaft reverser, the input shaft of the double-shaft reverser is connected with the driving end of the driving motor through a first electromagnetic coupling and a telescopic connecting shaft, the two output shafts of the double-shaft reverser are respectively connected with the shaft of the triangular cam and the rotating rod on the surface of the eccentric disc, and a second electromagnetic coupling is arranged between the rotating rod and the output shaft of the double-shaft reverser.

[0014] Preferably, the liftable freeze-thaw mechanism comprises a lifting cylinder fixed at the top of the support, and a semiconductor freeze-thaw assembly is fixed to the telescopic end of the lifting cylinder, the semiconductor freeze-thaw assembly comprises a fixed shell, a water-cooling circulating heat sink and a plurality of semiconductor refrigerating pieces are mounted in the fixed shell, the lower surfaces of the plurality of semiconductor refrigerating pieces are connected with a uniform temperature plate facilitating cold and heat conduction, and flexible pipes are connected to the water inlets and outlets of the water-cooling circulating heat sink.

[0015] Preferably, the switching assembly comprises a guide rod fixed on the side wall of the support, the top of the water flow spraying head and the erosion liquid spraying head are slidably connected with the guide rod, a connecting plate is fixed between the water flow spraying head and the erosion liquid spraying head, a switching cylinder is further fixed on the side wall of the support, and the telescopic end of the switching cylinder is connected with the erosion liquid spraying head.

[0016] Preferably, the water outlets of the water flow spraying head and the erosion liquid spraying head are arranged at an angle of 30°.

[0017] Preferably, the top of the base is provided with a detection bin, and the concrete block fixing table, the multidirectional fatigue testing mechanism, the liftable freeze-thaw mechanism and the liquid spraying mechanism are arranged in the detection bin.

[0018] Preferably, the surface of the base is provided with a drainage groove, the bottom of the drainage groove is connected to two drainage pipes, the top of each of the two drainage pipes is connected to an electric switch valve, and the drainage ends of the two drainage pipes extend to the outside of the base.

[0019] This invention provides a fatigue testing device for the bond between a waterstop and concrete at a construction joint. It has the following beneficial effects:

[0020] This invention, through the design of a multi-directional fatigue testing mechanism, changes the traditional unidirectional static test of the bonding strength of waterstops. By using a multi-directional fatigue testing mechanism with reciprocating motion in multiple directions, it simulates the expansion and contraction changes of construction joints in different directions under real-world conditions, greatly improving the accuracy of bonding fatigue experiments. At the same time, it is designed with a liftable freeze-thaw mechanism and a spraying mechanism to simulate different tunnel environments, such as freeze-thaw cycles and chemical erosion, and simulate extreme working conditions with multiple coupled fields. Different testing methods are selected for different tunnel conditions, and the long-term durability of the waterstop at the bond with concrete is evaluated through comprehensive experiments. Attached Figure Description

[0021] Figure 1 This is a perspective view of a fatigue testing device for the bond between a waterstop and concrete at a construction joint, according to the present invention.

[0022] Figure 2 This is an internal overall structural diagram of a fatigue testing device for the bond between a waterstop and concrete at a construction joint, according to the present invention.

[0023] Figure 3 This is a front view of a fatigue testing device for the bond between a waterstop and concrete at a construction joint, according to the present invention.

[0024] Figure 4 This is an overall structural diagram of the multi-directional fatigue testing mechanism in the fatigue testing device for the bond between the waterstop and concrete at a construction joint according to the present invention.

[0025] Figure 5 This is an overall structural diagram of the horizontal and vertical moving components in a fatigue test device for the bond between a waterstop and concrete at a construction joint, according to the present invention.

[0026] Figure 6 This is an overall structural diagram of the spraying mechanism in the fatigue test device for the bond between the waterstop and concrete at a construction joint according to the present invention.

[0027] Figure 7 This is an exploded view of the semiconductor freeze-thaw assembly in the fatigue test device for the bond between the waterstop at the construction joint and the concrete according to the present invention.

[0028] Figure 8 This invention provides a fatigue testing device for the bond between a waterstop and concrete at a construction joint. Figure 2 A bird's-eye view.

[0029] Wherein, 1, base; 11, drainage groove; 12, drainage pipeline; 13, electric switch valve; 2, concrete block fixing table; 3, multidirectional fatigue test mechanism; 31, clamping assembly; 32, horizontal and vertical moving assembly; 321, fixing frame; 322, horizontal moving frame; 323, vertical moving frame; 324, triangular cam; 325, connecting rod; 33, reciprocating stretching assembly; 331, rotating rod; 332, supporting block; 333, eccentric disc; 334, connecting rod; 335, fixed rod; 34, driving assembly; 341, driving motor; 342, double-shaft commutator; 343, first electromagnetic coupling; 344, telescopic connecting shaft; 345, second electromagnetic coupling; 4, liftable freeze-thaw mechanism; 41, lifting cylinder; 42, semiconductor freeze-thaw assembly; 421, fixed shell; 422, semiconductor refrigerating sheet; 423, uniform temperature plate; 424, water-cooling circulating heat sink; 5, liquid spraying mechanism; 51, water flow spraying head; 52, erosion liquid spraying head; 53, switching assembly; 531, guide rod; 532, switching cylinder; 6, side plate frame; 7, supporting table; 8, support; 9, detection bin. DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative work are within the protection scope of the present application.

[0031] As Figures 1-8 shown, the embodiment of the present application provides a construction joint water stop belt and concrete bonding fatigue test device, and the specific implementation is as follows:

[0032] Embodiment 1

[0033] The embodiment provides a construction joint water stop belt and concrete bonding fatigue test device, a base 1, a concrete block fixing table 2 and a multidirectional fatigue test mechanism 3 are arranged on the upper surface of the base 1, the concrete block fixing table 2 is used for fixing a poured concrete test block, fixed plates are arranged on the two sides of the concrete block fixing table 2, locking rods are arranged on the two sides of the fixed plates, the fixed plates are used for stably fixing concrete test blocks of a standard size, the multidirectional fatigue test mechanism 3 comprises a clamping assembly 31, a horizontal-vertical moving assembly 32, a reciprocating stretching assembly 33 and a driving assembly 34, the clamping assembly 31 is used for fixing a water stop belt bonded with a concrete block, so that the multidirectional fatigue test mechanism 3 drives the water stop belt to perform multidirectional operations such as forward and backward stretching, horizontal movement and vertical movement, thereby meeting the actual construction environment requirement, the horizontal-vertical moving assembly 32 and the reciprocating stretching assembly 33 are used for driving the water stop belt to perform multidirectional fatigue tests, and the driving assembly 34 is used for driving the horizontal-vertical moving assembly 32 and the reciprocating stretching assembly 33 to move.

[0034] A side plate frame 6 is slidably connected to the surface of the base 1, the horizontal-vertical moving assembly 32 is located on one side of the side plate frame 6, the horizontal-vertical moving assembly 32 comprises a fixed frame 321 fixed to the surface of the side plate frame 6, a horizontal moving frame 322 is slidably connected to the inside of the fixed frame 321, a vertical moving frame 323 is slidably connected to the inside of the horizontal moving frame 322, a triangular cam 324 is arranged in the inside of the vertical moving frame 323, the triangular cam 324 rotates in the inside of the vertical moving frame 323, the shaft of the triangular cam 324 is connected with the driving assembly 34, when the driving assembly 34 drives the triangular cam 324 to rotate, under the eccentric effect of the triangular cam 324, the vertical moving frame 323 on the outer surface of the triangular cam 324 can move up and down and left and right, forming a horizontal-vertical-horizontal-vertical rectangular track, a connecting rod 325 is fixed to the surface of the vertical moving frame 323, the clamping assembly 31 is installed on the outer surface of the connecting rod 325, so that the clamping assembly 31 can drive the water stop belt to perform reciprocating motion in the rectangular track, thereby realizing multidirectional fatigue tests, specifically, the clamping assembly 31 comprises a U-shaped frame, an adjusting rod is threadedly connected to the surface of the U-shaped frame, a movable clamping plate is rotatably connected to the bottom end of the adjusting rod, the movable clamping plate can be adjusted to clamp and fix water stop belts of different thicknesses.

[0035] The reciprocating stretching assembly 33 comprises a rotating rod 331 rotatably connected with a supporting block 332 fixed on the surface of the side plate frame 6, the bottom of the rotating rod 331 is fixed with an eccentric disc 333, the surface of the eccentric disc 333 is rotatably connected with a connecting rod 334, one side of the connecting rod 334 is provided with the supporting table 7, the connecting rod 334 is rotatably connected with a fixed rod 335 on the surface of the supporting table 7, when the rotating rod 331 rotates, the eccentric disc 333 can be driven to rotate, since the eccentric disc 333 is connected with the rotating rod 331 and the fixed rod 335, and the supporting table 7 is fixed on the surface of the base 1 and does not move, therefore, under the action of the rotation of the eccentric disc 333, the side plate frame 6, the clamping assembly 31 and the horizontal and vertical moving assembly 32 can be driven to move forward and backward as a whole, so that the reciprocating stretching fatigue detection is realized.

[0036] The driving assembly 34 comprises a driving motor 341 fixed on the surface of the supporting table 7, the surface of the side plate frame 6 is fixed with a double-shaft commutator 342, the input shaft of the double-shaft commutator 342 is connected with the driving end of the driving motor 341 through a first electromagnetic coupling 343 and a telescopic connecting shaft 344, the two output shafts of the double-shaft commutator 342 are respectively connected with the shaft of the triangular cam 324 and the rotating rod 331 on the surface of the eccentric disc 333, the second electromagnetic coupling 345 is arranged between the rotating rod 331 and the output shaft of the double-shaft commutator 342, the arrangement of the double-shaft commutator 342 can realize multi-directional fatigue detection by using one driving motor 341, the arrangement of the telescopic connecting shaft 344 can avoid the interference caused by the movement of the reciprocating stretching assembly 33, the first electromagnetic coupling 343 and the second electromagnetic coupling 345 can realize the disconnection or connection of the shaft body by short-circuiting, for example, when only the reciprocating stretching test is needed, the first electromagnetic coupling 343 can be disconnected, so that only the single reciprocating stretching fatigue test can be realized, and the practicability is higher.

[0037] Embodiment 2

[0038] Since the positions of different tunnels are different, the geological environments are also different, and the tunnel environment will be subjected to different conditions such as water erosion and geological permafrost, and when the adhesive fatigue test is performed, if these conditions are also considered, the accuracy of the experiment can be greatly improved.

[0039] A liftable freezing and thawing mechanism 4 is arranged above the concrete block fixing table 2 and is connected with the base 1 through a support 8, when freezing and thawing of the concrete test block is needed, since the tunnel concrete is generally only contacted with the permafrost and the erosion water on one side, only one side of the concrete test block needs to be subjected to freezing and thawing, the whole test block does not need to be placed in the freezing and thawing environment, and the cost of the device can be greatly reduced, specifically, the liftable freezing and thawing mechanism 4 comprises a lifting cylinder 41 fixed on the top of the support 8, and a semiconductor freezing and thawing assembly 42 is fixed on the telescopic end of the lifting cylinder 41, when freezing and thawing is needed, the semiconductor freezing and thawing assembly 42 can be attached to the surface of the concrete test block to realize freezing and thawing.

[0040] The semiconductor freeze-thaw assembly 42 comprises a fixed shell 421, the inside of the fixed shell 421 is mounted with a water-cooled circulating heat sink 424 and a plurality of semiconductor refrigerating pieces 422, the semiconductor refrigerating pieces 422 can realize the function conversion of refrigeration / heating by switching the current direction through the Peltier effect reversibility of TEC, the lower surfaces of the plurality of semiconductor refrigerating pieces 422 are commonly connected with a uniform plate 423 for conveniently conducting cold and heat, the inside of the uniform plate 423 is packaged with a temperature sensor for conveniently monitoring the temperature in real time, the water inlets and outlets of the water-cooled circulating heat sink 424 are connected with flexible pipes, the lengths of the flexible pipes are kept unrestricted within the lifting orientation of the semiconductor freeze-thaw assembly 42, the flexible pipes are connected with an external cooling water tank, and the water-cooled circulating heat sink 424 can be supplied with water in circulation.

[0041] One side of the liftable freeze-thaw mechanism 4 is provided with a liquid spraying mechanism 5, the liquid spraying mechanism 5 comprises a water flow spraying head 51 and an etching liquid spraying head 52, which are used for spraying liquid to the bonding part of the concrete block and the water stop belt, and the water flow spraying head 51 and the etching liquid spraying head 52 are connected through a switching assembly 53. The switching assembly 53 comprises a guide rod 531 fixed on the side wall of the support 8, the top of the water flow spraying head 51 and the etching liquid spraying head 52 are slidably connected with the guide rod 531, a connecting plate is fixed between the water flow spraying head 51 and the etching liquid spraying head 52, and a switching cylinder 532 is also fixed on the side wall of the support 8, and the extension end of the switching cylinder 532 is connected with the etching liquid spraying head 52. Since the etching liquid has a certain etching effect, the ordinary non-etching water and the etching liquid do not share one spraying head. When etching water is needed to be sprayed, for example, Figure 2 and Figure 6 As shown in the figure, the etching liquid spraying head 52 sprays the bonding interface of the concrete block and the water stop belt, the directional spraying bonding interface (non-full surface), and the preferential permeability of the groundwater along the construction joint is reproduced. When the groundwater of the tunnel has no etching effect, the switching cylinder 532 is extended to push the etching liquid spraying head 52 and the water flow spraying head 51 to move, and the water flow spraying head 51 is moved to the bonding interface of the concrete block and the water stop belt. The water outlets of the water flow spraying head 51 and the etching liquid spraying head 52 are both inclinedly arranged at an angle of 30°, which is convenient for spraying water to the bonding interface of the concrete block and the water stop belt.

[0042] The top of the base 1 is mounted with a detection bin 9, and the concrete block fixing table 2, the multidirectional fatigue test mechanism 3, the liftable freeze-thaw mechanism 4 and the liquid spraying mechanism 5 are all arranged in the inside of the detection bin 9.

[0043] The surface of the base 1 is provided with a drainage groove 11, the bottom of the drainage groove 11 is communicated with two drainage pipelines 12, the top of each of the two drainage pipelines 12 is connected with an electrically operated on-off valve 13, and the drainage ends of the two drainage pipelines 12 extend to the outside of the base 1, which is convenient for separately recycling the non-etching water and the etching solution.

[0044] Example 3

[0045] Take the Qiu Zhuang tunnel in the Ji Dazhe high-speed rail as an example, the overall profile of the project is: the total length is 760m, the maximum buried depth of the tunnel is about 62m, the rock mass joint fissure is developed, and the surrounding rock stability is good; the groundwater is generally rich, the water quality has no corrosiveness to the concrete structure; the special rock soil is expansive soil and seasonal frozen soil, and the overall geological condition is medium. Therefore, when detecting the tunnel condition, the influence of the erosive water and the seasonal frozen soil on the bonding place of the concrete block and the water stop belt needs to be considered.

[0046] In the specific operation, the water stop belt is poured into the concrete test block according to the specific construction mode, and the other side of the water stop belt should be poured into another concrete test block, but in order to facilitate the experiment, the clamping assembly 31 is fixed on one side to conduct a fatigue test on the bonding place of the concrete block and the water stop belt. In order to monitor the experimental effect in real time, a piezoelectric ceramic sensor can be arranged at the bonding place of the concrete and the water stop belt to detect the debonding degree of the bonding interface when the concrete test block and the water stop belt are poured.

[0047] In the detection, the bonding interface (non-full surface) can be sprayed through the directional spraying, and the preferential permeation of the groundwater along the construction joint is reproduced. Since the groundwater is erosive, an acid solution (pH=3.5-4.0) containing Cl⁻ / SO4²⁻ can be sprayed through the spraying head 52, and the concentration can reach 10 times that of the site, so that the laboratory acceleration of 20 years of erosion can be realized. Then, the concrete surface is subjected to freezing and thawing through the liftable freezing and thawing mechanism 4. The spraying liquid forms a high-concentration salt solution during the freezing period, which aggravates the spalling of the concrete and reproduces the unique damage mode in the frozen soil area. At the same time, the water stop belt is stretched through the multi-directional fatigue test mechanism 3 to simulate the extreme working condition of multi-field coupling, and the long-term durability of the bonding place of the water stop belt and the concrete is evaluated through comprehensive experiments.

[0048] Embodiment 4

[0049] Take the Ditan Mountain No. 1 tunnel in the Ji Dazhe high-speed rail as an example, the overall profile of the project is: the total length is 440m, the ground elevation is 65m-151m, the relative height difference is 86m, the structure is generally not developed, the rock mass joint fissure is developed, and the surrounding rock stability is generally good to good; the groundwater is generally rich, the water quality has no corrosiveness to the concrete structure; the special rock soil is expansive soil and seasonal frozen soil. Therefore, the erosive liquid does not need to be considered when the concrete construction material is in service, and the operation is basically the same as that of Embodiment 3, the only difference is that the non-erosive water sprayed through the water flow spraying head 51 is used instead of the erosive liquid to conduct the experiment. Although the embodiments of the present application have been shown and described, it can be understood by those skilled in the art that various changes, modifications, replacements and deformations can be made to these embodiments without departing from the principles and spirits of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A fatigue testing device for the bond between a waterstop and concrete at a construction joint, comprising a base (1), characterized in that: The upper surface of the base (1) is provided with a concrete block fixing platform (2) and a multi-directional fatigue testing mechanism (3). A liftable freeze-thaw mechanism (4) is provided directly above the concrete block fixing platform (2). The liftable freeze-thaw mechanism (4) is connected to the base (1) through a bracket (8). A liquid spraying mechanism (5) is provided on one side of the liftable freeze-thaw mechanism (4). The multi-directional fatigue testing mechanism (3) includes a clamping component (31), a horizontal and vertical moving component (32), a reciprocating tension component (33), and a driving component (34). The clamping component (31) is used to fix the waterstop bonded to the concrete block. The horizontal and vertical moving component (32) and the reciprocating tension component (33) are used to drive the waterstop to perform multi-directional fatigue testing. The driving component (34) is used to drive the horizontal and vertical moving component (32) and the reciprocating tension component (33) to move. The spraying mechanism (5) includes a water jet nozzle (51) and an erosion liquid nozzle (52) for spraying liquid onto the bonding area between the concrete block and the waterstop. The water jet nozzle (51) and the erosion liquid nozzle (52) are connected by a switching assembly (53). The base (1) is slidably connected to a side plate frame (6). The horizontal and vertical moving assembly (32) is located on one side of the side plate frame (6). The horizontal and vertical moving assembly (32) includes a fixed frame (321) fixed to the surface of the side plate frame (6). A horizontal moving frame (322) is slidably connected inside the fixed frame (321). A vertical moving frame (323) is slidably connected inside the horizontal moving frame (322). A triangular cam (324) is provided inside the vertical moving frame (323). The triangular cam (324) rotates inside the vertical moving frame (323). The shaft of the triangular cam (324) is connected to the drive assembly (34). The reciprocating tension assembly (33) includes a rotating rod (331), which is rotatably connected to a support block (332) fixed on the surface of the side plate frame (6). An eccentric disk (333) is fixed at the bottom of the rotating rod (331), and a connecting rod (334) is rotatably connected to the surface of the eccentric disk (333). A support platform (7) is provided on one side of the connecting rod (334), and the connecting rod (334) is rotatably connected to a fixed rod (335) on the surface of the support platform (7). The drive assembly (34) includes a drive motor (341) fixed on the surface of the support platform (7), a dual-axis commutator (342) fixed on the surface of the side plate frame (6), the input shaft of the dual-axis commutator (342) is connected to the drive end of the drive motor (341) through a first electromagnetic coupling (343) and a telescopic connecting rod (344), the two output shafts of the dual-axis commutator (342) are respectively connected to the shaft of the triangular cam (324) and the rotating rod (331) on the surface of the eccentric disk (333), and a second electromagnetic coupling (345) is provided between the rotating rod (331) and the output shaft of the dual-axis commutator (342). The liftable freeze-thaw mechanism (4) includes a lifting cylinder (41) fixed to the top of the bracket (8), and a semiconductor freeze-thaw assembly (42) is fixed to the telescopic end of the lifting cylinder (41).

2. The fatigue testing device for the bond between the waterstop and concrete at construction joints according to claim 1, characterized in that: A connecting rod (325) is fixed to the surface of the longitudinal moving frame (323), and the clamping assembly (31) is installed on the outer surface of the connecting rod (325).

3. The fatigue testing device for the bond between the waterstop and concrete at construction joints according to claim 1, characterized in that: The semiconductor freeze-thaw assembly (42) includes a fixed shell (421), inside which a water-cooled circulating heat sink (424) is installed and connected to multiple semiconductor cooling chips (422). The lower surfaces of the multiple semiconductor cooling chips (422) are connected to a heat spreader (423) for convenient heat conduction. The inlet and outlet of the water-cooled circulating heat sink (424) are connected to flexible pipes.

4. The fatigue testing device for the bond between the waterstop and concrete at construction joints according to claim 1, characterized in that: The switching assembly (53) includes a guide rod (531) fixed on the side wall of the bracket (8). The tops of the water jet head (51) and the erosion liquid jet head (52) are slidably connected to the guide rod (531). A connecting plate is fixed between the water jet head (51) and the erosion liquid jet head (52). A switching cylinder (532) is also fixed on the side wall of the bracket (8). The telescopic end of the switching cylinder (532) is connected to the erosion liquid jet head (52).

5. The fatigue testing device for the bond between the waterstop and concrete at construction joints according to claim 1, characterized in that: The nozzles of both the water jet head (51) and the erosion liquid jet head (52) are inclined at a 30° angle.

6. The fatigue testing device for the bond between the waterstop and concrete at construction joints according to claim 1, characterized in that: The top of the base (1) is equipped with a testing chamber (9), and the concrete block fixing platform (2), the multi-directional fatigue testing mechanism (3), the liftable freeze-thaw mechanism (4) and the spraying mechanism (5) are all located inside the testing chamber (9).

7. The fatigue testing device for the bond between the waterstop and concrete at construction joints according to claim 1, characterized in that: The surface of the base (1) is provided with a drainage groove (11), and the bottom of the drainage groove (11) is connected to two drainage pipes (12). The top of the two drainage pipes (12) is connected to an electric switch valve (13), and the drainage ends of the two drainage pipes (12) extend to the outside of the base (1).

Images