A test method for torsional performance of steel beams

Abstract

The invention belongs to the field of loading test of civil engineering structure test, and specifically relates to a test method for the torsion performance of a steel beam. The test method adopts a special device for measurement. The device comprises a portal reaction frame, a reaction pedestal, an MTS actuator, a torsion transmission device, a limit turntable and a limit base. The device converts the thrust provided by the MTS actuator into torque through the torsion transmission device, and limits the steel beam specimen during the test loading through the limit device, so that the rotation center of the steel beam coincides with the torsion center of the device, thereby innovatively realizing the torsion test of the steel beam, and converting the angle that is difficult to directly test in the torsion angle measurement method into a test length, so that the test process is convenient, efficient and more accurate.

Description

Technical Field

[0001] The invention belongs to the field of loading tests for civil engineering structure experiments, and in particular relates to a method for testing the torsion performance of a steel beam. Background Art

[0002] During the use of steel structure buildings, the steel beams located outside the building often undergo torsion deformation under the load of canopies, balconies, etc. Therefore, it is very important to study the mechanical properties of steel structure components under torque. The torsion loading device is mainly used to perform torsion tests on specimens. The relationship curve between torque and torsion angle is obtained through test data analysis, and the torsion performance of the specimen is evaluated based on the curve.

[0003] In the prior art, most torsion loading devices can only perform torsion tests on small-scale specimens such as bolt rods and steel bars, and use AC servo motors and ordinary hydraulic jacks as power devices. For torsion tests on large specimens, there are limitations such as small torque and instability. In addition, the existing method directly tests the torsion angle, which is difficult to measure and its torsion angle measuring instrument is restricted by factors such as the need to be customized and high cost, which makes it difficult to meet current actual needs.

[0004] Therefore, whether it is possible to combine the test conditions available in the existing structural test sites to provide a simpler and more efficient test method for the torsional performance of steel beams, and apply it to the torsional performance test of steel beams with box-type, I-type, T-type and other cross-sectional forms has become one of the urgent problems to be solved by technical personnel in this field. Summary of the invention

[0005] In view of many shortcomings in the prior art, the present invention provides a method for testing the torsional performance of a steel beam, which is measured by a special device, wherein the device comprises a gantry reaction frame, a reaction pedestal, an MTS actuator, a torsion transmission device, a limit turntable and a limit base. The device converts the thrust provided by the MTS actuator into torque through the torsion transmission device, and limits the steel beam specimen during test loading through the limit device, so that the rotation center of the steel beam coincides with the torsion center of the device, thereby innovatively realizing the torsion test of the steel beam, and converting the angle that is difficult to directly test in the torsion angle measurement method into a test length, so that the test process is convenient, efficient and more accurate.

[0006] The specific technical solutions of the present invention are as follows:

[0007] A method for testing the torsion performance of a steel beam, the specific steps are as follows:

[0008] First, install the steel beam on the corresponding test device, then turn on the switch of the MTS actuator to start the torsion test of the steel beam. The MTS actuator drives the loading plate to move up and down. During the advancement process, the loading plate interacts with the I-beam to generate a torsional force, which is transmitted to the end of the steel beam through the first embedded plate cavity, causing one end of the steel beam to twist relative to the other end.

[0009] In the above process, point A is the torsion center, point B is the positioning pin fixing point, and point C is the wire displacement meter fixing point;

[0010] a is the initial distance from the positioning pin to the ground wire displacement meter, a ′ is the distance from the positioning pin to the ground wire displacement meter during the test loading, b is the distance from the torsion center to the fixed point of the ground wire displacement meter, c is the distance from the torsion center to the positioning pin, α is the torsion angle, β is the initial value of the angle between the fixing point B of the positioning pin of the wire displacement meter to the torsion center A and the torsion center A to the fixed point C of the ground wire displacement meter, γ is the measured value of the angle between the fixing point B of the positioning pin of the wire displacement meter to the torsion center A and the torsion center A to the fixed point C of the ground wire displacement meter during the test, and the calculation formula is as follows:

[0011] Torsion angle of steel beam: α=β-γ,

[0012]

[0013] ;

[0014] The test device used in the above-mentioned test includes a gantry reaction frame, a reaction platform, an MTS actuator, a torsion transmission device, a limit turntable and a limit base;

[0015] Furthermore, the portal reaction frame is fixedly connected to the horizontal plane of the reaction pedestal by anchor bolts; two MTS actuators are provided, one of which is vertically connected to the bottom of the portal reaction frame beam by a base, with its end facing downward and connected to the upper loading plate of the torsion transmission device; the other MTS actuator is fixed to the horizontal plane of the reaction pedestal by a base, with its end facing upward and connected to the lower loading plate of the torsion transmission device; the connections are all ball joints, and the design of the ball joints can ensure that when the torsion transmission device is rotated under force, the force applied by the MTS actuator is always perpendicular to the loading plate.

[0016] The torsion transmission device comprises a loading plate, an I-beam, a first embedded plate cavity, a triangular support member, a first connecting plate, a mounting seat, a first clamping plate and a second clamping plate, wherein the loading plates are two and are symmetrically arranged on the upper and lower sides of both ends of the I-beam, and further, the two sides of the loading plates are fixedly connected to the I-beam through at least four triangular support members; a through hole is arranged in the middle of the I-beam and is welded to the first embedded plate cavity as a whole; the first embedded plate cavity is a cavity structure for mounting a steel beam;

[0017] In the above structure, the MTS actuator can monitor the magnitude of the applied force in real time through the sensor; and when the load is applied to the end of the MTS actuator, the loading plate and the I-beam will rotate along the torsion center, and then the first embedded plate cavity will rotate relative to the end of the steel beam.

[0018] Preferably, the loading plate is provided with bolt holes corresponding to the end heads of the MTS actuators, wherein the bolt holes contain screws for clamping the loading plate and the end heads of the MTS actuators, thereby ensuring that the two are tightly connected.

[0019] The first clamping plate and the second clamping plate are arranged inside the first embedded plate cavity; threaded holes are evenly arranged on the upper side and right side of the first embedded plate cavity, a pin hole is arranged in the middle of the upper side, and the first clamping plate is arranged with a pin hole corresponding to the first embedded plate cavity; threaded rods are arranged in the threaded holes to press against the first clamping plate and the second clamping plate to clamp the steel beam, and the pin rods arranged in the pin holes pass through the first embedded plate cavity and the first clamping plate to fix the steel beam to avoid movement or loosening during the torsion process; mounting seats are symmetrically arranged on both sides of the first embedded plate cavity, and the mounting seats are welded to the I-beam as a whole; threaded holes are evenly arranged on the mounting seats. In order to cooperate with the use of the above-mentioned pin holes and pin rods, it is necessary to open a limit hole at the corresponding position of the top end of the steel beam.

[0020] The limit device includes a limit turntable and a limit base, wherein the limit turntable includes a first connecting plate, a turntable, a cylindrical steel shaft and a rolling bearing, and further, the first connecting plate is provided with a threaded hole corresponding to the mounting seat, and is fixedly connected to the mounting seat through the threaded hole; one end of the cylindrical steel shaft is fixedly connected to the middle of the first connecting plate, and the rolling bearing is sleeved into the other end of the cylindrical steel shaft; the rolling bearing includes an inner ring and an outer ring, the inner ring is sleeved on the cylindrical steel shaft, and the outer ring is fixedly connected to the inner side of the turntable; the turntable is a smooth solid turntable, and the limit holes are evenly arranged on the upper, lower, left and right sides of the turntable, and the limit holes are connected with basket bolts and steel strands used to connect the reaction frame and the reaction pedestal; this structure provides sufficient strength and rigidity while limiting the spatial movement of the torsion center, so as to achieve the coincidence of the rotation center of the steel beam with the torsion center of the device, thereby ensuring the accuracy and safety of the test.

[0021] The limiting base includes a second embedded plate cavity, a peripheral support member, a third clamping plate, a fourth clamping plate and a bottom plate, and the two sides of the second embedded plate cavity are welded into one with the connecting bottom plate through the peripheral support member; threaded holes are evenly arranged on the upper side and the right side of the second embedded plate cavity, and a pin hole is arranged in the middle of the upper side, and threaded rods for tightening the third clamping plate and the fourth clamping plate are arranged in the threaded holes, and pin rods passing through the second embedded plate cavity, the third clamping plate and the steel beam are arranged in the pin holes; mounting holes corresponding to the vertical surface of the reaction force pedestal are respectively arranged on the upper and lower sides of the bottom plate, and screws for clamping the bottom plate and the reaction force pedestal are arranged in the mounting holes.

[0022] A mounting plate is installed at the center position below the loading plate on the upper side of the I-beam, and a wire-pull type displacement meter is installed on the reaction base below the mounting plate. Preferably, mounting plates are provided on both sides of the I-beam. When in use, positioning pins are provided on the mounting plate, and the wire end of the wire-pull type displacement meter can be fixed on the positioning pins.

[0023] The torsional performance testing device adopting the above-mentioned structure can fix the steel beam between the first embedded plate cavity and the second embedded plate cavity. By adjusting the first to fourth clamping plates, steel beams with different cross-sectional sizes and different cross-sectional thicknesses can be fastened in the embedded plate cavity; and by adjusting the distance between the portal reaction frame and the limit base, the testing requirements of steel beams of different lengths can be met.

[0024] During the specific test, as described in the above method, first install the steel beam according to the above requirements, then turn on the switch of the MTS actuator to start the torsion test of the steel beam. The MTS actuator drives the loading plate to move up and down. During the advancement process, the loading plate interacts with the I-beam to generate a torsional force, which is transmitted to the end of the steel beam through the first embedded plate cavity, causing one end of the steel beam to twist relative to the other end, thereby completing the torsion performance test. The torque is obtained by multiplying the output force of the MTS actuator by the lever arm.

[0025] Furthermore, the wire displacement meters are arranged at the same height on both sides of the I-beam, and the method of double-channel acquisition and averaging can effectively improve the data accuracy;

[0026] In order to ensure the measurement accuracy of the above method, the initial value β of the angle between the positioning pin and the torsion center and the torsion center and the fixed point of the ground wire displacement meter must be greater than 78°; if the angle is less than this, the detection accuracy will decrease. Therefore, considering the size of the equipment and the ease of operation, the above angle is optimized. The torsion angle of the steel beam can be obtained through the above calculation.

[0027] Compared with the prior art, the method for testing the torsional performance of a steel beam provided by the present invention has the following advantages:

[0028] (1) The torsion angle measurement method is designed to match the torsion device. The MTS actuator applies an outward push pressure, which can limit the rotation direction of the torsion device on the one hand, and prevent the connection between the MTS actuator and the portal reaction frame and reaction wall from being pulled out due to the application of inward tension on the other hand, thus ensuring the safety of the test.

[0029] (2) Currently, there are few devices used for torsional loading of steel beams. Generally, AC servo motors and ordinary hydraulic jacks are used as driving devices, which have disadvantages such as small loading torque and complex design. This device does not require additional power driving device design. It uses MTS actuators for loading, and the upper and lower MTS actuators have equal thrust and opposite directions, which can easily achieve large torque loading and is suitable for steel beam torsional loading tests.

[0030] (3) Currently, most of the torsion loading equipment used for large specimens adopts single-end loading. This equipment can realize synchronous loading at both ends, has good test reliability, and can also ensure the safety of large-scale structural tests.

[0031] (4) The torsion loading device and the limit base are provided with limit holes, which can effectively prevent the relative sliding of the steel beam and the torsion loading device. The limit turntable is used as a spatial limit device to provide sufficient lateral restraint force. It has a simple structure and high overall strength, so that the rotation center of the steel beam coincides with the torsion center of the device, ensuring the accuracy of the test results.

[0032] (5) The first embedded plate cavity of the torsion loading device and the second embedded plate cavity of the limiting base and the steel beam are clamped by bolts. The thickness of the clamped steel plate can be changed, which can be applicable to steel beams with different cross-sectional sizes, cross-sectional thicknesses and various cross-sectional types. There is no connection constraint between the torsion loading device and the limiting base, which can be applicable to steel beams of different lengths, thereby improving the applicability of the device.

[0033] (6) The middle part of the torsion loading device is a plate cavity with holes on both sides. The first connecting plate is connected to the mounting seat by bolts. It is easy to install and disassemble, and the steel beam specimen can be quickly replaced, which improves the practicality of the device.

[0034] (7) The device has the characteristics of simple structure, flexible use and easy maintenance, and has good social and economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a schematic diagram of the overall structure of the device for testing the torsional performance of a steel beam according to the present invention;

[0036] Figure 2 It is a schematic diagram of the structure of the torsion transmission device of the present invention;

[0037] Figure 3 This is a schematic diagram of the structure of the limit turntable of the present invention;

[0038] Figure 4 This is a schematic diagram of the structure of the limiting base of the present invention;

[0039] Figure 5 It is a schematic diagram of the torsion angle measurement method of the present invention;

[0040] Figure 6 Schematic diagram of the torque and torsion angle detection results of different box-shaped steel beams in the embodiment;

[0041] In the figure, 1 is a torsion transmission device, 11 is a loading plate, 12 is an I-beam, 13 is a first embedded plate cavity, 14 is a triangular support member, 15 is a mounting seat, 16 is a first clamping plate, 17 is a second clamping plate, 18 is a mounting plate, 2 is a limit turntable, 21 is a first connecting plate, 22 is a turntable, 23 is a cylindrical steel shaft, 24 is a rolling bearing, 3 is a limit base, 31 is a second embedded plate cavity, 32 is a peripheral support member, 33 is a third clamping plate, 34 is a fourth clamping plate, 35 is a bottom plate, 4 is a steel beam specimen, 5 is an MTS actuator, 6 is a basket bolt, 7 is a wire displacement meter, 8 is a portal reaction frame, and 9 is a reaction pedestal. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0043] Device Embodiment

[0044] like Figure 1-4 As shown, the present invention first provides a device for testing the torsion performance of a box-type steel beam, comprising a portal reaction frame (8), a reaction pedestal (9), an MTS actuator (5), a torsion transmission device (1), a limit turntable (2) and a limit base (3);

[0045] Furthermore, the portal reaction frame (8) is fixedly connected to the horizontal plane of the reaction pedestal (9) by anchor bolts; two MTS actuators (5) are provided, one of which is vertically connected to the bottom of the crossbeam of the portal reaction frame (8) by a base, with its end facing downward and connected to the upper loading plate of the torsion transmission device (1); the other MTS actuator is fixed to the horizontal plane of the reaction pedestal (9) by a base, with its end facing upward and connected to the lower loading plate of the torsion transmission device (1);

[0046] The torsion transmission device (1) comprises a loading plate (11), an I-beam (12), a first embedded plate cavity (13), a triangular support member (14), a mounting seat (15), a first clamping plate (16) and a second clamping plate (17), wherein the loading plates (11) are two and are symmetrically arranged at the upper and lower sides of both ends of the I-beam (12), and further, the two sides of the loading plate (11) are fixedly connected to the I-beam (12) via at least four triangular support members (14); the loading plate (11) is provided with a bolt hole corresponding to the end of the MTS actuator (5), and the bolt hole contains a screw for clamping the loading plate (11) and the end of the MTS actuator (5); a through hole is provided in the middle of the I-beam (12) and is welded to the first embedded plate cavity (13) as a whole;

[0047] A first clamping plate (16) and a second clamping plate (17) are arranged inside the first embedded plate cavity (13); threaded holes are evenly arranged on the upper side and right side of the first embedded plate cavity (13), a pin hole is arranged in the middle of the upper side, and the first clamping plate (16) is provided with a pin hole corresponding to the first embedded plate cavity (13); threaded rods are arranged in the threaded holes for tightening the first clamping plate (16) and the second clamping plate (17), and pin rods are arranged in the pin holes to pass through the first embedded plate cavity (13) and the first clamping plate (16) to fix the box-shaped steel beam (4); mounting seats (15) are symmetrically arranged on both sides of the first embedded plate cavity (13), and the mounting seats (15) are welded to the I-beam (12) as a whole; threaded holes are evenly arranged on the mounting seats (15).

[0048] The position limiting device comprises a position limiting rotating disk (2) and a position limiting base (3), wherein the position limiting rotating disk (2) comprises a first connecting plate (21), a rotating disk (22), a cylindrical steel shaft (23) and a rolling bearing (24);

[0049] Furthermore, the first connecting plate (21) is provided with a threaded hole corresponding to the mounting seat (15), and is fixedly connected to the mounting seat through the threaded hole; one end of the cylindrical steel shaft (23) is fixedly connected to the middle of the first connecting plate (21), and the rolling bearing (24) is inserted into the other end of the cylindrical steel shaft (23); the rolling bearing (24) comprises an inner ring and an outer ring, the inner ring is sleeved on the cylindrical steel shaft (23), and the outer ring is fixedly connected to the inner side of the turntable (22); the turntable (22) is evenly provided with limit holes on the upper, lower, left and right sides, and the limit holes are connected with a basket bolt (6) and a steel strand for connecting the horizontal plane of the reaction frame (8) and the reaction pedestal (9);

[0050] The limiting base (3) comprises a second embedded plate cavity (31), a peripheral support member (32), a third clamping plate (33), a fourth clamping plate (34) and a bottom plate (35); the second embedded plate cavity (31) is welded to a connecting bottom plate (35) on both sides through the peripheral support member (32); threaded holes are evenly arranged on the upper side and right side of the second embedded plate cavity (31); a pin hole is arranged in the middle of the upper side; threaded rods for tightening the third clamping plate (33) and the fourth clamping plate (34) are arranged in the threaded holes; a pin rod passing through the second embedded plate cavity (31), the third clamping plate (33) and the box-shaped steel beam (4) is arranged in the pin hole; mounting holes corresponding to the vertical surface of the reaction force pedestal (9) are respectively arranged on the upper and lower sides of the bottom plate (35); screws for clamping the bottom plate (35) and the reaction force pedestal (9) are arranged in the mounting holes.

[0051] A mounting plate (18) is installed at a central position below the loading plate on the upper side of the I-beam (12), and a wire-drawing displacement meter (7) is installed on a reaction pedestal below the mounting plate (18). Preferably, mounting plates (18) are provided on both sides of the I-beam (12). When in use, a positioning pin is provided on the mounting plate (18), and a wire end of the wire-drawing displacement meter (7) is fixed on the positioning pin.

[0052] Method Embodiment

[0053] A method for testing the torsion performance of a steel beam, the specific steps are as follows:

[0054] First, install the box-shaped steel beam according to the above requirements, then turn on the switch of the MTS actuator to start the torsion test of the box-shaped steel beam. The MTS actuator drives the loading plate to move up and down. During the advancement process, the loading plate interacts with the I-beam to generate a torsional force, which is transmitted to the end of the box-shaped steel beam through the first embedded plate cavity, causing one end of the box-shaped steel beam to twist relative to the other end.

[0055] The torque is obtained by multiplying the output force of the MTS actuator (5) by the lever arm;

[0056] In the above process, point A is the torsion center, point B is the positioning pin fixing point, and point C is the wire displacement meter fixing point;

[0057] a is the initial distance from the positioning pin to the ground wire displacement meter, a ′ is the distance from the positioning pin to the ground wire displacement meter during the test loading, b is the distance from the torsion center to the fixed point of the ground wire displacement meter, c is the distance from the torsion center to the positioning pin, α is the torsion angle, β is the initial value of the angle between the fixing point B of the positioning pin of the wire displacement meter to the torsion center A and the torsion center A to the fixed point C of the ground wire displacement meter, γ is the measured value of the angle between the fixing point B of the positioning pin of the wire displacement meter to the torsion center A and the torsion center A to the fixed point C of the ground wire displacement meter during the test, and the calculation formula is as follows:

[0058] Torsion angle of steel beam: α=β-γ,

[0059]

[0060] ;

[0061] Positioning pins are arranged at the same height on both sides of the I-beam, and the method of double-channel acquisition and averaging can effectively improve the data accuracy; Figure 5 shown.

[0062] In order to ensure the measurement accuracy, the method needs to satisfy that the initial value of the angle between the positioning pin and the torsion center and the torsion center to the fixed point of the ground wire displacement meter is greater than 78°. The corresponding initial value β in this embodiment is 79.6°. The torsion angle of the box-type steel beam can be obtained through the above calculation.

[0063] Experimental example

[0064] By using the scheme of the above method embodiment and the device in the device embodiment, the torsion performance test of the box-shaped steel beam without a hole, the box-shaped steel beam with a circular hole and the box-shaped steel beam with a square hole is carried out respectively; wherein the size information of the box-shaped steel beam without a hole, the box-shaped steel beam with a circular hole and the box-shaped steel beam with a square hole is as follows:

[0065] The specimen of the box-shaped steel beam without opening is 2200 mm long, with a cross-sectional size of 400 mm × 200 mm and a wall thickness of 8 mm;

[0066] The box-shaped steel beam with circular hole has a specimen length of 2200 mm, a cross-sectional size of 400 mm × 200 mm, a wall thickness of 8 mm, and a box-shaped steel beam with a circular hole of 100 mm in diameter in the middle of the web;

[0067] The box-type steel beam with square hole has a specimen length of 2200 mm, a cross-sectional size of 400 mm×200 mm, a wall thickness of 8 mm, and a box-type steel beam with a square hole of 100 mm×100 mm in the middle of the web.

[0068] After testing, the torsional performance of box-shaped steel beams without holes, box-shaped steel beams with round holes and box-shaped steel beams with square holes is as follows: Figure 6 As shown, the results are as follows:

[0069] The ultimate torques of the three test box-type steel beams are as follows: without hole (9.1°, 142.7 kN·m), with round hole (8.5°, 137.0 kN·m), and with square hole (7.7°, 129.0 kN·m).

[0070] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for testing the torsional performance of a steel beam, characterized in that: The specific steps are as follows: First, install the steel beam in the test device, then turn on the switch of the MTS actuator to start the torsion test of the steel beam. During the advancement process, the loading plate and the I-beam interact to generate a torsional force, which is transmitted to the end of the steel beam through the first embedded plate cavity, causing one end of the steel beam to twist relative to the other end. In the above process, point A is set as the torsion center, point B is set as the positioning pin fixing point, and point C is set as the wire displacement meter fixing point; a is the initial distance from the positioning pin to the ground wire displacement meter, a ′ is the distance from the positioning pin to the ground wire displacement meter during the test loading, b is the distance from the torsion center to the fixed point of the ground wire displacement meter, c is the distance from the torsion center to the positioning pin, α is the torsion angle, β is the initial value of the angle between the fixing point B of the positioning pin of the wire displacement meter to the torsion center A and the torsion center A to the fixed point C of the ground wire displacement meter, γ is the measured value of the angle between the fixing point B of the positioning pin of the wire displacement meter to the torsion center A and the torsion center A to the fixed point C of the ground wire displacement meter during the test, and the calculation formula is as follows: Torsion angle of steel beam: α=β-γ, ； The test device comprises a gantry reaction frame (8), a reaction pedestal (9), an MTS actuator (5), a torsion transmission device (1), a limit turntable (2) and a limit base (3); the gantry reaction frame (8) is fixedly connected to the horizontal plane of the reaction pedestal (9) by anchor bolts; two MTS actuators (5) are provided, one of which is vertically connected to the bottom of the crossbeam of the gantry reaction frame (8) by a base, with its end facing downward and connected to the upper loading plate of the torsion transmission device (1); the other MTS actuator is fixed to the horizontal plane of the reaction pedestal (9) by a base, with its end facing upward and connected to the lower loading plate of the torsion transmission device (1); The torsion transmission device (1) comprises a loading plate (11), an I-beam (12), a first embedded plate cavity (13), a triangular support member (14), a mounting seat (15), a first clamping plate (16) and a second clamping plate (17), wherein the loading plates (11) are two and are symmetrically arranged at the upper and lower sides of both ends of the I-beam (12); a bolt hole corresponding to the end of the MTS actuator (5) is opened on the loading plate (11), and a screw for clamping the loading plate (11) and the end of the MTS actuator (5) is arranged in the bolt hole; a through hole is arranged in the middle of the I-beam (12) and is welded to the first embedded plate cavity (13) to form an integral body; A first clamping plate (16) and a second clamping plate (17) are arranged inside the first embedded plate cavity (13); threaded holes are evenly arranged on the upper side and right side of the first embedded plate cavity (13), a pin hole is arranged in the middle of the upper side, and the first clamping plate (16) is provided with a pin hole corresponding to the first embedded plate cavity (13); mounting seats (15) are symmetrically arranged on both sides of the first embedded plate cavity (13), and the mounting seats (15) are welded to an I-beam (12) as a whole; threaded holes are evenly arranged on the mounting seats (15); The position limiting device comprises a position limiting rotating disk (2) and a position limiting base (3), wherein the position limiting rotating disk (2) comprises a first connecting plate (21), a rotating disk (22), a cylindrical steel shaft (23) and a rolling bearing (24); The first connecting plate (21) is provided with a threaded hole corresponding to the mounting seat (15), and is fixedly connected to the mounting seat through the threaded hole; one end of the cylindrical steel shaft (23) is fixedly connected to the middle of the first connecting plate (21), and the rolling bearing (24) is inserted into the other end of the cylindrical steel shaft (23); limit holes are evenly arranged on the upper, lower, left and right sides of the turntable (22), and the limit holes are connected with a basket bolt (6) and a steel strand for connecting the horizontal plane of the reaction frame (8) and the reaction pedestal (9); The limiting base (3) comprises a second embedded plate cavity (31), a peripheral support member (32), a third clamping plate (33), a fourth clamping plate (34) and a bottom plate (35); the second embedded plate cavity (31) is welded to a connecting bottom plate (35) on both sides through the peripheral support member (32); threaded holes are evenly arranged on the upper side and right side of the second embedded plate cavity (31), and a pin hole is arranged in the middle of the upper side; the bottom plate (35) is respectively provided with mounting holes corresponding to the vertical surface of the reaction force pedestal (9) on the upper and lower sides, and screws for clamping the bottom plate (35) and the reaction force pedestal (9) are arranged in the mounting holes; A mounting plate (18) is installed at a central position below the loading plate on the upper side of the I-beam (12), a wire-type displacement meter (7) is installed on a reaction pedestal below the mounting plate (18), and a positioning pin is provided on the mounting plate (18).

2. The method for testing the torsional performance of a steel beam according to claim 1, characterized in that: The torque is obtained by multiplying the output force of the MTS actuator (5) by the lever arm.

3. The method for testing the torsional performance of a steel beam according to claim 1, characterized in that: Positioning pins are arranged at the same height on both sides of the I-beam, and the double-channel acquisition and averaging method is used to improve data accuracy.

4. The method for testing the torsional performance of a steel beam according to claim 1, characterized in that: The initial value of the angle between the positioning pin and the torsion center and the torsion center and the fixing point of the ground pull-wire displacement meter is greater than 78°.

5. The method for testing the torsional performance of a steel beam according to claim 1, characterized in that: Both sides of the loading plate (11) are fixedly connected to the I-beam (12) via at least four triangular support members (14).

6. The method for testing the torsional performance of a steel beam according to claim 1, characterized in that: A threaded rod is arranged in the threaded hole of the first embedded plate cavity (13) for tightening the first clamping plate (16) and the second clamping plate (17), and a pin is arranged in the pin hole to pass through the first embedded plate cavity (13) and the first clamping plate (16) to fix the steel beam (4).

7. The method for testing the torsional performance of a steel beam according to claim 1, characterized in that: The rolling bearing (24) comprises an inner ring and an outer ring, the inner ring being sleeved on the cylindrical steel shaft (23), and the outer ring being fixedly connected to the inner side of the rotating disk (22).

8. The method for testing the torsional performance of a steel beam according to claim 1, characterized in that: A threaded rod for tightening the third clamping plate (33) and the fourth clamping plate (34) is arranged in the threaded hole of the second embedded plate cavity (31), and a pin rod penetrating the second embedded plate cavity (31), the third clamping plate (33) and the steel beam (4) is arranged in the pin hole.

9. The method for testing the torsional performance of a steel beam according to claim 1, characterized in that: Mounting plates (18) are provided on both sides of the I-beam (12), and positioning pins are provided on the mounting plates (18), and the ends of the pull-wire displacement meters (7) are fixed on the positioning pins.

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