CN107314936B - Environment-fatigue load coupling simulation device capable of being regulated and controlled freely - Google Patents

Abstract

The invention discloses a freely adjustable environment-fatigue load coupling simulation device, which includes a spherical joint connection part, a top plate, an upper loading part, a screw, a rubber limit block, a sliding bar and a locking screw, a bubble level, and a lower loading part. , supports and corrosive solution tanks. There is a rectangular slot in the middle of the top plate for the upper loading part to slide. The screws pass through the upper loading part and the top plate respectively. The rotating screw can flexibly adjust the position of the upper loading part to adapt to different types and sizes of test pieces. The rubber limit block is used to block the screw rod, and the sliding bar and locking screw are used to fix the rubber limit block. The corrosion solution tank is used to provide a variety of different corrosion environment conditions to simulate fatigue load conditions on test pieces under different environments. Bubble levels and supports are used to ensure precise positioning of the loading device to improve control accuracy. This device is easy to operate, has strong controllability, and has extensive application value in coupling simulations of different environments and fatigue loads.

Description

A freely adjustable environment-fatigue load coupling simulation device

Technical field

The invention relates to a freely adjustable environment-fatigue load coupling simulation device.

Background technique

Fatigue load can cause the service performance of materials and components to degrade or even cause fatigue brittle fracture, and the corrosive environment can accelerate this degradation or fracture process. In terms of metal material testing, corrosion fatigue crack growth rate is an important basis for fatigue damage tolerance analysis of engineering components. At present, the corrosion fatigue crack growth rate test of materials is limited by the loading device, the anti-corrosion requirements are high, and the applicable specimen form is relatively single. For example, there is an existing device that covers a compact tensile specimen by designing an environmental box. The environmental box has a hole at the notch of the specimen, and a rubber skin is used at the hole to isolate the extensometer and the corrosive solution. However, this device has high sealing requirements. , and the rubber skin may affect the sensitivity of the extensometer. Problems such as tightness and corrosive solution leakage also exist in some tests on central crack tensile specimens. There are also devices developed for single-sided notched specimens to prevent the extensometer from being corroded by contact with the solution. The disadvantages are that the scope of application is limited, and the loading point of the loading device has poor adjustability or does not have the ability to continuously adjust. In terms of testing beam components, existing methods mostly accelerate corrosion by energizing the main bars of the test beam, and then perform fatigue loading when the main bars of the test beam reach the designed corrosion rate. This method is a study on the fatigue performance of components after corrosion. It does not consider the coupling of corrosion environment and fatigue load, and is inconsistent with the actual situation.

Contents of the invention

In view of the shortcomings of the existing technology, the present invention provides a freely adjustable environment-fatigue load coupling simulation device that is novel in structure, economically feasible, and highly practical.

In order to achieve the above technical objectives, the technical solution of the present invention is:

A freely adjustable environment-fatigue load coupling simulation device includes a spherical joint connection part, a loading part and a support part. The support member is provided with a piece to be tested, and the loading part is connected to the actuator of the fatigue testing machine through a ball hinge connection part and performs pressure loading on the piece to be tested.

The spherical hinge connection part includes a spherical hinge and a connecting piece. The spherical shell of the spherical hinge is connected to the actuator of the fatigue testing machine, and the spherical body of the spherical hinge is connected to the loading part through the connecting piece.

The loading part includes an upper loading part and a lower loading part, and the upper loading part and the lower loading part are respectively arranged at the upper and lower ends of the test piece. The upper loading part includes a top plate, an upper loading part and a screw. The top plate is connected to the actuator of the fatigue testing machine through a ball joint connection part. There is a rectangular slot on the top plate. The upper loading part is The top is provided with a protrusion, the shape of the protrusion matches the rectangular groove and is embedded in the rectangular groove, and the protrusion has a hole for the screw to pass through in the extending direction of the rectangular groove, and an internal thread is provided in the hole to To match the screw, the top plate has through holes at both ends of the rectangular slot for the screw to penetrate into the rectangular slot and pass through the holes on the protrusion. The bottom of the upper loading part is a tooth-shaped protrusion and contacts the test piece. the upper end. The lower loading part includes a lower loading part, and the top of the lower loading part is provided with a toothed protrusion and contacts the lower end of the piece to be tested.

The support component includes a leveling auxiliary component for horizontally supporting the test piece. The leveling auxiliary component is a rectangular body, with the test piece placed on the top surface, and a gap left in the middle for accommodating the lower loading component.

The freely adjustable environment-fatigue load coupling simulation device also includes a corrosive solution tank, a corrosive solution is provided in the corrosive solution tank, and the support member and the lower loading member are placed in the corrosive solution tank. Inside, the piece to be tested is immersed in the corrosive solution.

The freely adjustable environment-fatigue load coupling simulation device, the spherical hinge connection part includes a spherical hinge and two connectors, and the spherical shell of the spherical hinge is connected to the actuator of the fatigue testing machine , the two ends of the sphere of the ball hinge are symmetrically fixed with horizontal steel rods, the two connectors are respectively provided at both ends of the ball hinge and fixed on the loading part, and the connectors are both provided with holes for accommodating steel rods. The ball hinge penetrates the steel rod into the hole of the connecting piece to drive the loading part.

In the freely adjustable environment-fatigue load coupling simulation device, the upper loading part also includes at least one rubber limit block. The rubber limit block is in an inverted U shape and is arranged in a rectangular groove. Snap onto the screw.

In the freely adjustable environment-fatigue load coupling simulation device, the upper loading part also includes sliding bars equal to the number of rubber limit blocks and locking screws for fixing the sliding bars. The sliding The strip is arranged perpendicularly to the rectangular groove on the top plate. The two ends of the sliding strip are hook-shaped parts extending downward and buckled at the two opposite edges of the top plate. The hook-shaped parts are provided with screw holes and are secured with locking screws. Pass through the screw hole for fixation, and the position where the sliding bar passes through the rectangular groove is the position of the rubber limit block set in the rectangular groove.

The freely adjustable environment-fatigue load coupling simulation device also includes a bubble level, and the bubble level is arranged on the top plate of the upper loading part.

A freely adjustable environment-fatigue load coupling simulation device, including a ball joint connection part, a loading part and a support part. The support part is provided with a test piece, and the loading part is connected to the fatigue test through the ball joint connection part. The actuator of the machine is loaded with pressure on the test piece.

The spherical hinge connection part includes a spherical hinge and a connecting piece. The spherical shell of the spherical hinge is connected to the actuator of the fatigue testing machine, and the spherical body of the spherical hinge is connected to the loading part through the connecting piece.

The loading part includes an upper loading part and a lower loading part, and the upper loading part and the lower loading part are respectively arranged at the upper and lower ends of the test piece. The upper loading part includes a top plate, at least two upper loading parts and a number of screws equal to that of the upper loading parts. The top plate is connected to the actuator of the fatigue testing machine through a ball joint connection part, and the top plate has a hole connected to the upper loading part. There are rectangular slots with an equal number of pieces. The top of the upper loading piece is provided with a number of protrusions equal to the rectangular slot. The shape of the protrusions matches the rectangular slot and is embedded in the rectangular slot, and the protrusions are along the edge. There are holes in the extending direction of the rectangular slot for the screws to pass through. Only one of the holes on the protrusion of the upper loading member has internal threads to match the screws, and each hole with internal threads is not in the same rectangular slot. Inside, the top plate has through holes at both ends of the rectangular slot for the screws to penetrate into the rectangular slot and pass through the holes on the protrusions. The bottom of the upper loading part is a tooth-shaped protrusion and contacts the test piece. upper end. The lower loading part includes at least one lower loading part, and the top of the lower loading part is provided with a toothed protrusion and contacts the lower end of the piece to be tested. The support component includes a leveling auxiliary component for horizontally supporting the test piece. The leveling auxiliary component is a rectangular body, with the test piece placed on the top surface, and a gap left in the middle for accommodating the lower loading component.

The freely adjustable environment-fatigue load coupling simulation device also includes a corrosive solution tank, a corrosive solution is provided in the corrosive solution tank, and the support member and the lower loading member are placed in the corrosive solution tank. Inside, the piece to be tested is immersed in the corrosive solution.

The freely adjustable environment-fatigue load coupling simulation device, the spherical hinge connection part includes a spherical hinge and two connectors, and the spherical shell of the spherical hinge is connected to the actuator of the fatigue testing machine , the two ends of the sphere of the ball hinge are symmetrically fixed with horizontal steel rods, the two connectors are respectively provided at both ends of the ball hinge and fixed on the loading part, and the connectors are both provided with holes for accommodating steel rods. The ball hinge penetrates the steel rod into the hole of the connecting piece to drive the loading part.

In the freely adjustable environment-fatigue load coupling simulation device, the upper loading part also includes at least one rubber limit block. The rubber limit block is in an inverted U shape and is arranged in a rectangular groove. Snap onto the screw.

In the freely adjustable environment-fatigue load coupling simulation device, the upper loading part also includes sliding bars equal to the number of rubber limit blocks and locking screws for fixing the sliding bars. The sliding The strip is arranged perpendicularly to the rectangular groove on the top plate. The two ends of the sliding strip are hook-shaped parts extending downward and buckled at the two opposite edges of the top plate. The hook-shaped parts are provided with screw holes and are secured with locking screws. Pass through the screw hole for fixation, and the position where the sliding bar passes through the rectangular groove is the position of the rubber limit block set in the rectangular groove.

The freely adjustable environment-fatigue load coupling simulation device also includes a bubble level, and the bubble level is arranged on the top plate of the upper loading part.

The technical effect of the present invention is that the loading position can be freely adjusted and controlled with high precision, and the number of upper and lower loading parts can be appropriately increased or decreased to meet the needs of different tests, and can be applied to concrete cube test blocks or concrete prismatic test blocks. The splitting test is also suitable for the corrosion fatigue crack growth test of single-side notch specimens of different sizes, and the environment-fatigue coupled loading test of small beam components of different sizes. This device has simple structure, convenient operation and low cost, and has wide application value in coupling simulation of different environments and fatigue loads.

The present invention will be further described below in conjunction with the accompanying drawings.

Description of the drawings

Figure 1 is a schematic diagram of the overall structure of the present invention;

Figure 2 is an exploded schematic diagram of the present invention;

Figure 3 is a schematic diagram of the specific structure of the ball joint connection part;

Figure 4 is a schematic diagram of the specific structure of the upper loading member;

Figure 5 is a schematic diagram of the use of rubber limit blocks, sliding bars and locking screws;

Figure 6 is a right side view of the present invention;

Figure 7 is a left side view of the present invention.

Among them, 1 is the fatigue testing machine actuator, 201 is the ball joint, 202 is the connector, 301 is the top plate, 302 is the sliding bar and locking screw, 303 is the screw, 304 is the bubble level, 305 is the upper loading part, 306 It is the rubber limit block, 401 is the extensometer, 402 is the single-sided notch specimen, 5 is the support member, 6 is the lower loading member, and 7 is the corrosion solution tank.

Detailed ways

Example 1

This embodiment includes a ball joint connection part, a loading part and a support part. The support part is provided with a piece to be tested, and the loading part is connected to the actuator of the fatigue testing machine through the ball joint connection part and performs pressure loading on the test piece;

The spherical hinge connection part includes a spherical hinge and two connecting pieces. The spherical shell of the spherical hinge is connected to the actuator of the fatigue testing machine. Horizontal steel rods are fixed symmetrically on both ends of the ball of the spherical hinge. The two connectors described above are respectively provided at both ends of the spherical hinge and fixed on the loading part. The connectors are both provided with holes for accommodating steel rods. The spherical hinge drives the loading by penetrating the steel rod into the hole of the connector. part; using the adjustability of the ball hinge, the loading part can be flexibly adjusted within a certain range;

The loading part includes an upper loading part and a lower loading part. The upper loading part and the lower loading part are respectively arranged at the upper and lower ends of the test piece; the upper loading part includes a top plate, an upper loading part and a screw, and the top plate is connected through a ball hinge connection part. The actuator of the fatigue testing machine has a rectangular groove on the top plate, and a protrusion is provided on the top of the upper loading part. The shape of the protrusion matches and is embedded in the rectangular groove, and the protrusion is along the rectangular groove. There is a hole in the extension direction for the screw to pass through. The hole is provided with internal threads to match the screw. The top plate has through holes at both ends of the rectangular slot for the screw to penetrate into the rectangular slot and pass through the boss. hole, the upper loading part can slide in the rectangular groove by rotating the screw. The bottom of the upper loading part is a tooth-like protrusion and contacts the upper end of the test piece; the lower loading part includes a lower loading part, and the top of the lower loading part has a The tooth-like protrusion contacts the lower end of the test piece; the support is a leveling auxiliary piece, used to support the test piece horizontally and to ensure that the upper and lower loading parts are flush. The leveling auxiliary piece is a rectangular body and is placed on the top surface. The piece to be tested, and there is a gap in the middle to accommodate the lower loading piece.

In order to test the specimen in a corrosive environment, this embodiment is provided with a corrosive solution tank. The corrosive solution tank is equipped with a corrosive solution. The support member and the lower loading member are both placed in the corrosive solution tank. The support member and the lower loading member are All are coated with anti-corrosion coatings, and the test pieces are immersed in the corrosive solution. Before starting the loading test, the supports need to be removed.

In order to prevent the screw from rotating during fatigue loading and at the same time better wedge the gap between the upper loading part and the screw interface, the loading part also includes at least one rubber limit block, which is in the shape of an inverted U. into the rectangular groove and snap onto the screw. Compared with steel, rubber material is a soft material. Once it is stuck into the screw, it can adapt to the thread shape on the screw to a certain extent, and can play a better stabilizing role.

In order to prevent the rubber limit blocks from gradually loosening and jumping out of the groove during fatigue loading, the loading part also includes the same number of slide bars as the rubber limit blocks and locking screws for fixing the slide bars. The strip is arranged perpendicularly to the rectangular groove on the top plate. The two ends of the sliding strip are hook-shaped parts extending downward and buckled at the two opposite edges of the top plate. The hook-shaped parts are provided with screw holes and are secured with locking screws. Pass through the screw holes to secure. Locking screws secure the slide bar to the top plate. The position where the sliding bar passes through the rectangular groove is the position of the rubber limit block set in the rectangular groove. In this way, the slide bar blocks the rubber limit block from above, which can effectively prevent the rubber limit block from moving abnormally.

In order to keep the entire device level to ensure the test effect, this embodiment also includes a bubble level, which is arranged on the top plate of the upper loading part. This allows the unit to be adjusted according to the bubble level to maintain level. Bubble levels and supports are used to ensure the precise position of the loading device and improve control accuracy. In addition, the ball joint connection part is adjustable. When the position of the test piece is deviated, eccentric loading will occur, causing the upper loading part to no longer be horizontal. At this time, the position of the test piece needs to be adjusted. This feedback mechanism helps improve test accuracy.

The device of this embodiment can be used for the splitting test of concrete cube test blocks or concrete prismatic test blocks.

Example 2

This embodiment includes a ball joint connection part, a loading part and a support part. The support part is provided with a piece to be tested, and the loading part is connected to the actuator of the fatigue testing machine through the ball joint connection part and performs pressure loading on the test piece;

The loading part includes an upper loading part and a lower loading part. The upper loading part and the lower loading part are respectively arranged at the upper and lower ends of the test piece; the upper loading part includes a top plate, at least two upper loading parts and a number of screws equal to the upper loading parts. , the top plate is connected to the actuator of the fatigue testing machine through a ball hinge connection part. The top plate is provided with a number of rectangular grooves equal to the number of upper loading parts. The top of the upper loading part is provided with a number of protrusions equal to the number of rectangular grooves. The shape of the protrusions It matches and is embedded in the rectangular groove, and the protrusion has holes along the extending direction of the rectangular groove for the screw rod to pass through. Only one of the holes on the protrusion of each upper loading member is provided with an internal thread to match the screw rod. , and each hole with internal threads is not in the same rectangular groove. The top plate has through holes at both ends of the rectangular groove for the screw rod to penetrate into the rectangular groove and pass through the hole on the boss. , the upper loading part can slide in the rectangular groove by rotating the screw, and one screw only controls the sliding of one upper loading part. The bottom of the upper loading part is a tooth-like protrusion and contacts the upper end of the test piece; the lower part The loading part includes at least one lower loading part. The top of the lower loading part is provided with a toothed protrusion and contacts the lower end of the test piece; the support part is a leveling auxiliary part, used to horizontally support the test piece and to ensure upper and lower loading. The parts are flush, the leveling auxiliary part is a rectangular body, the test piece is placed on the top surface, and there is a gap in the middle to accommodate the lower loading part.

This embodiment also includes the same ball joint connection part, corrosion solution tank, rubber limit block, sliding bar, locking screw and bubble level as in Embodiment 1.

The difference between Embodiment 2 and Embodiment 1 is that the number of upper and lower loading parts is multiple, which can meet the needs of loading tests at multiple points on the specimen under different circumstances. At the same time, for the convenience of processing, this embodiment is provided with a number of protrusions equal to the number of rectangular grooves on the top of the upper loading member. In fact, according to specific needs, only one protrusion can be provided on the top of each upper loading part, and the protrusions of different upper loading parts are different according to the specific positions corresponding to different rectangular grooves.

As shown in Figures 1 and 2, the entire upper loading part 3 is installed and connected to the fatigue testing machine actuator 1 through the spherical hinge connection part 2 by drilling holes in the top plate 301. The specific structure of the spherical hinge connection part 2 is as shown in Figure 3. Show. A rectangular slot is provided in the middle of the top plate 301 for the upper loading part 305 to slide. Two screw rods 303 pass through the two upper loading parts 305 and the top plate 301 respectively. Rotating the screw rod 303 can realize the sliding of the upper loading part 305. As shown in Figure 4, the upper loading member 305 has two circular holes. One hole is provided with threads suitable for the screw 303, while the other hole is smooth. Therefore, one screw 303 can control only one upper part. The position of the loading part 305 moves, so that the position of the upper loading part 305 can be adjusted according to different specimen sizes.

The rubber stopper 306 is used to block the screw 303 to prevent the position of the upper loading member 305 from changing during the test. The sliding bar and locking screw 302 can slide along the top plate 301. When the position of the sliding bar is determined, the rubber stopper 306 can be fixed by tightening the screw, thereby further fixing the upper loading member 305, as shown in Figure 5.

The bubble level 304 is fixed on the top plate 301 to ensure that the entire upper loading part 3 is level. The support member 5 is used to horizontally support the test piece and ensure that the upper and lower loading parts are parallel and aligned, as shown in Figures 6 and 7. Before the test starts, the support 5 can be removed to perform the fatigue loading test. The bubble level 304 and the support 5 are both used to ensure the accurate position of the loading device and improve control accuracy.

The corrosive solution tank 7 passes through the lower loading member 6 and contains solution for simulating the corrosive environment. If necessary, the corrosive solution tank 7 can be replaced with an existing closed salt spray tank or a seawater circulation power device. The lower loading part 6 is welded to the bottom steel plate as a whole, and then connected to the fatigue testing machine base using bolts.

Based on the device of the invention and with reference to the standard "Standard test method for measuring offatigue crack growth rates", corrosion fatigue crack growth tests can be carried out. The basic test method is: turn the unilateral notched specimen upside down so that the notch of the specimen is located at the water surface of the corrosive solution, and install the extensometer at the notch position of the specimen. According to the flexibility method, use the extensometer to monitor the opening displacement of the unilateral notched specimen. Thus, the crack growth rate of the specimen under the coupling action of corrosive solution and fatigue load can be monitored.

Based on the device of the invention and referring to the specification "Standard for Test Methods of Concrete Structures", the bending performance test of small beam-type components under the coupling effect of corrosive environment and fatigue load can also be simulated to study the service life and bending stiffness of the component under the coupling effect of environment and fatigue load. and other performance degradation rules.

Claims (10)

1. The environment-fatigue load coupling simulation device capable of being regulated and controlled freely is characterized by comprising a spherical hinge connecting part, a loading part and a supporting piece, wherein a test piece to be tested is arranged on the supporting piece, and the loading part is connected with an actuator of a fatigue testing machine through the spherical hinge connecting part and carries out pressure loading on the test piece to be tested;

the spherical hinge connecting part comprises a spherical hinge and a connecting piece, a spherical shell of the spherical hinge is connected to an actuator of the fatigue testing machine, and a sphere of the spherical hinge is connected to the loading part through the connecting piece;

the loading part comprises an upper loading part and a lower loading part, and the upper loading part and the lower loading part are respectively arranged at the upper end and the lower end of the test piece to be tested; the upper loading part comprises a top plate, an upper loading part and a screw rod, wherein the top plate is connected with an actuator of the fatigue testing machine through a spherical hinge connecting part, a rectangular groove is formed in the top plate, a bulge is arranged at the top of the upper loading part, the bulge is matched with the rectangular groove in shape and embedded into the rectangular groove, a hole for the screw rod to pass through is formed in the bulge along the extending direction of the rectangular groove, internal threads are arranged in the hole to be matched with the screw rod, through holes are formed in the two side ends of the top plate at the position of the rectangular groove for the screw rod to penetrate into the rectangular groove and penetrate through the hole in the bulge, and the bottom of the upper loading part is a toothed bulge and is contacted with the upper end of a test piece to be tested; the lower loading part comprises a lower loading piece, and the top of the lower loading piece is provided with tooth-shaped bulges and contacts with the lower end of the test piece to be tested;

the support piece comprises a leveling auxiliary piece for horizontally supporting a test piece to be tested, the leveling auxiliary piece is a cuboid, the test piece to be tested is placed on the top surface, and a gap for accommodating the lower loading piece is reserved in the middle;

the test piece to be tested is immersed in the corrosive solution.

2. The environment-fatigue load coupling simulation device capable of being freely regulated and controlled according to claim 1, wherein the spherical hinge connecting part comprises a spherical hinge and two connecting pieces, a spherical shell of the spherical hinge is connected to an actuator of a fatigue testing machine, steel bars which are horizontally arranged are symmetrically fixed at two ends of a sphere of the spherical hinge, the two connecting pieces are respectively arranged at two ends of the spherical hinge and are fixed on the loading part, holes for accommodating the steel bars are formed in the connecting pieces, and the spherical hinge penetrates into the holes of the connecting pieces through the steel bars to drive the loading part.

3. The freely controllable environment-fatigue load coupling simulation device according to claim 1, wherein the upper loading part further comprises at least one rubber limiting block, and the rubber limiting block is in an inverted U shape, is arranged in the rectangular groove and is buckled on the screw rod.

4. The environment-fatigue load coupling simulation device capable of being freely regulated and controlled according to claim 3, wherein the upper loading part further comprises sliding strips and locking screws, the number of the sliding strips is equal to that of the rubber limiting blocks, the sliding strips are perpendicular to the rectangular grooves on the top plate and are arranged on the top plate, two ends of each sliding strip are downwardly extending hook-shaped pieces and are buckled at two opposite edges of the top plate, the hook-shaped pieces are provided with screw holes and are fixed through the locking screws penetrating through the screw holes, and the positions of the sliding strips penetrating through the rectangular grooves are the positions of the rubber limiting blocks arranged in the rectangular grooves.

5. The freely controllable environment-fatigue load coupling simulation apparatus according to claim 1, further comprising a bubble level disposed on the top plate of the upper loading portion.

6. The environment-fatigue load coupling simulation device capable of being regulated and controlled freely is characterized by comprising a spherical hinge connecting part, a loading part and a supporting piece, wherein a test piece to be tested is arranged on the supporting piece, and the loading part is connected with an actuator of a fatigue testing machine through the spherical hinge connecting part and carries out pressure loading on the test piece to be tested;

the spherical hinge connecting part comprises a spherical hinge and a connecting piece, a spherical shell of the spherical hinge is connected to an actuator of the fatigue testing machine, and a sphere of the spherical hinge is connected to the loading part through the connecting piece;

the loading part comprises an upper loading part and a lower loading part, and the upper loading part and the lower loading part are respectively arranged at the upper end and the lower end of the test piece to be tested; the upper loading part comprises a top plate, at least two upper loading parts and screws with the same number as the upper loading parts, the top plate is connected with an actuator of the fatigue testing machine through a spherical hinge connecting part, rectangular grooves with the same number as the upper loading parts are formed in the top plate, the number of protrusions with the same number as the rectangular grooves are formed in the top of the upper loading parts, the protrusions are matched with the rectangular grooves and are embedded into the rectangular grooves, holes for the screws to pass through are formed in the protrusions along the extending direction of the rectangular grooves, only one hole is formed in each upper loading part protrusion, the holes are provided with internal threads for matching the screws, the holes with the internal threads are not located in the same rectangular groove, through holes are formed in the two side ends of the top plate at the position of the rectangular groove for the screws to penetrate into the rectangular grooves and penetrate through the holes in the protrusions, the bottom of the upper loading parts are tooth-shaped protrusions and are in contact with the upper ends of test pieces to be tested; the lower loading part comprises at least one lower loading piece, and the top of the lower loading piece is provided with tooth-shaped bulges and contacts with the lower end of the test piece to be tested;

the support piece comprises a leveling auxiliary piece for horizontally supporting a test piece to be tested, the leveling auxiliary piece is a cuboid, the test piece to be tested is placed on the top surface, and a gap for accommodating the lower loading piece is reserved in the middle;

the test piece to be tested is immersed in the corrosive solution.

7. The environment-fatigue load coupling simulation device capable of being freely regulated and controlled according to claim 6, wherein the spherical hinge connecting part comprises a spherical hinge and two connecting pieces, a spherical shell of the spherical hinge is connected to an actuator of the fatigue testing machine, steel bars which are horizontally arranged are symmetrically fixed at two ends of a sphere of the spherical hinge, the two connecting pieces are respectively arranged at two ends of the spherical hinge and are fixed on the loading part, holes for accommodating the steel bars are formed in the connecting pieces, and the spherical hinge penetrates into the holes of the connecting pieces through the steel bars to drive the loading part.

8. The freely controllable environment-fatigue load coupling simulation device according to claim 6, wherein the upper loading part further comprises at least one rubber limiting block, and the rubber limiting block is in an inverted U shape, is arranged in the rectangular groove and is buckled on the screw rod.

9. The environment-fatigue load coupling simulation device capable of being freely regulated and controlled according to claim 8, wherein the upper loading part further comprises sliding strips and locking screws, the number of the sliding strips is equal to that of the rubber limiting blocks, the sliding strips are perpendicular to the rectangular grooves on the top plate and are arranged on the top plate, two ends of each sliding strip are downwardly extending hook-shaped pieces and are buckled at two opposite edges of the top plate, the hook-shaped pieces are provided with screw holes and are fixed through the locking screws penetrating through the screw holes, and the positions of the sliding strips penetrating through the rectangular grooves are the positions of the rubber limiting blocks arranged in the rectangular grooves.

10. The freely controllable environment-fatigue load coupling simulation apparatus according to claim 6, further comprising a bubble level disposed on the top plate of the upper loading portion.