A test device and test method for continuous two-end shear loading

Abstract

The present invention provides a test device and test method for continuous two-end shear loading. The test device includes a square outer frame, a bidirectional loading bracket, a hydraulic loading device, a winch lifting mechanism and a specimen base; the bidirectional loading bracket includes a support frame arranged along the diagonal of the outer frame and upper and lower loading frames respectively installed on the support frame, one end of the support frame is installed at one of the top corners of the square frame body through a rotating shaft, and the other end is provided with a connecting member fixed at the diagonal of the top corner, and the winch lifting mechanism is installed on the top of the outer frame and connected to the support frame through a steel wire rope. The hydraulic loading device includes a hydraulic pump and upper and lower loading jacks respectively installed on the upper and lower loading frames. The present invention improves the accuracy of the test results and the test efficiency, and can provide more comprehensive test research parameters for research such as the reinforcement of old residential areas with tight time and heavy tasks, and has good economic and social benefits.

Description

Technical Field

[0001] The present invention relates to the field of professional testing of building structures, and specifically to a testing device and a testing method for continuous two-end shear loading, which are mainly used for rapid and continuous large-scale research on the shear bearing capacity performance of test pieces constructed by masonry or the like. Background Art

[0002] In my country, almost all large and medium-sized cities have old urban areas. In order to speed up urban construction and improve the urban environment, many cities have started projects to strengthen old urban buildings. Large-scale reinforcement projects involve the study of many parameters, among which the study of the shear bearing capacity of the wall is an important parameter, which involves the study of the shear bearing capacity of the wall before and after reinforcement. In order to speed up the test progress and accurately and specifically study the shear bearing capacity of the wall, the diagonal loading shear test method described in the American National Standard ASTM E519-2015 can be used to study the shear bearing capacity of the wall.

[0003] The existing diagonal loading shear test method for the shear bearing capacity of walls is to place the specimen diagonally vertically on a large pressure testing machine for testing, which requires crane transportation each time, which is time-consuming and laborious. At the same time, the existing test method mainly adopts in-situ single-end loading, that is, the test is carried out by applying a load at one end of the specimen. When loading at one end, it is easy to generate a large edge load at the loading corner of the specimen, which will cause premature splitting failure under the action of this load. This has a large test data error for the study of the shear bearing capacity of the specimen, and the test failure phenomenon is not sufficient; and the existing test device needs to be reinstalled before each test, and it needs to be completely disassembled and repeated to the next specimen at the end. The steps are complicated and the physical consumption is large; the specimens are greatly affected by accidental factors such as the environment and human factors during the processing process, so each group of the same type of test needs to meet at least 3 specimens to ensure the accuracy of the test, which leads to a large number of specimens generated by more research variables during the test. If the original test plan is used to repeat the disassembly in each test, it will inevitably cause the test progress to be too slow and a large waste of manpower and other resources. Summary of the invention

[0004] In view of the problems existing in the existing in-situ single-ended diagonal shear test method, the present invention proposes a test device and a test method for continuous two-end shear loading. The test method of the present invention can realize bidirectional loading test, reduce the test data error of the shear bearing capacity of the specimen, and can realize continuous loading, improve the test efficiency, and provide more comprehensive test research parameters for the research on the reinforcement of old residential areas with tight time and heavy tasks, and has good economic and social benefits.

[0005] In order to achieve the above technical objectives, the present invention provides a test device for continuous two-end shear loading, which performs a shear loading test on a square test specimen, and is characterized in that: the test device includes a square outer frame with the same shape as the test specimen, a bidirectional loading bracket, a hydraulic loading device, a winch lifting mechanism and a specimen base; the bidirectional loading bracket includes a support frame arranged along the diagonal of the outer frame and an upper loading frame and a lower loading frame respectively installed on the support frame, one end of the support frame is installed at one of the top corners of the square frame body through a rotating shaft, and the other end is provided with a connecting member fixed at the diagonal of the top corner, the winch lifting mechanism is installed on the top of the outer frame, connected to the support frame by a steel wire rope, and when the connecting member is not fixed, the winch lifting mechanism drives the support frame to rotate up and down along the rotating shaft ; The upper loading frame and the lower loading frame both include a reaction plate and a loading support, the reaction plate is fixedly mounted on the support frame, and the loading support is slidably connected to the support frame; the hydraulic loading device includes an oil pressure pump, an upper loading jack and a lower loading jack, the upper loading jack and the lower loading jack are respectively mounted on the upper loading frame and the lower loading frame through jack holders, the electric oil pressure pump is respectively connected to the upper loading jack and the lower loading jack through oil pipes, and provides hydraulic power for the upper loading jack and the lower loading jack; during the loading test, the test specimen is placed on the specimen base, the outer frame is located outside the test specimen and the specimen base, and the diagonal of the outer frame is in the same straight line as the diagonal of the test specimen, and the two loading frames are located at two diagonal positions of the test specimen, and are in close contact with the corners of the test specimen through the loading supports respectively.

[0006] A further technical solution of the present invention is as follows: the test specimen is a square specimen with a side length of 900-1200 mm and a thickness of 200-250 mm; the height of the specimen base is 900-1100 mm, and the length of the specimen base is 180-210 mm less than the length of the test specimen; the outer frame includes two parallel square frames, the tops of the two square frames are connected as a whole by a first cross bar on one side, and are connected by a rotating shaft on the other side, and an oblique support rod is provided on the upper part of one side where the two square frames are connected by the rotating shaft, and the height of the oblique support rod is higher than the total height of the test specimen and the specimen base, and universal wheels are respectively provided at the bottom of the two square frames, and each universal wheel has its own braking mechanism.

[0007] A further technical solution of the present invention is as follows: the support frame comprises two symmetrical square bars, each of which is provided with a plurality of bolt holes, and the plurality of bolt holes are equidistantly distributed on the sides of the square bars, with the internal wires passing through the bars, and the diameter and hole spacing of the bolt holes are both 20-40 mm; one end of the two square bars is installed on one of the top corners of the square frame body through a rotating shaft, and the other end is connected through a second cross bar, and the ends of the two square bars provided with the second cross bar are connected to the diagonal parts of the square frame body through a connecting member; the winch lifting mechanism is connected to the middle part of the second cross bar through a steel wire rope; the connecting member comprises a lap groove arranged at the ends of the two square bars and a support rod arranged on the outer frame, and when the support frame rotates along the rotating shaft to the diagonal line of the outer frame, the support frame is lapped on the support rod through the lap groove at its end.

[0008] The better technical solution of the present invention is as follows: the hoist lifting mechanism includes a hoist, a pulley and a lifting wire rope, the hoist and the pulley are installed on the top of the outer frame, one end of the lifting wire rope is connected to the hoist and is connected to one end of the support frame with a connecting member around the pulley, and drives the support frame to rotate up and down along the rotating shaft in the outer frame.

[0009] A better technical solution of the present invention: the hydraulic pump is an electric hydraulic pump, the hydraulic pump is connected to the oil distributor through a main oil pipe, the oil distributor is respectively connected to the upper loading jack and the lower loading jack through two oil distribution pipes, for realizing synchronous actuation of the upper loading jack and the lower loading jack, and a pressure sensor is installed at the top position of the piston end of each jack.

[0010] The preferred technical solution of the present invention is as follows: the jack fixture is provided with two groups, which are respectively connected to the reaction plate and the loading support, each group of jack fixtures includes two symmetrically arranged arc-shaped clamping plates and a screw rod corresponding to each arc-shaped clamping plate, at least two fixing plates with thread holes are correspondingly welded on the reaction plate and the loading support, a rotating handle is provided at one end of the screw rod, and the thread on the screw rod matches the inner thread of the thread hole on the fixing plate; when the upper loading jack and the lower loading jack are installed, the jack is placed between the reaction plate and the loading support, and the two groups of jack fixtures are respectively placed on the piston end and the cylinder end of the jack to be installed, and the two arc-shaped clamping plates of each group of jack fixtures are symmetrically clamped on the outside of the jack, and each arc-shaped clamping plate is tightened and fixed to the jack after passing through the corresponding fixing plate through the screw rod.

[0011] The preferred technical solution of the present invention is as follows: the reaction plate includes a reaction plate base plate, transverse stiffening ribs, longitudinal support plates arranged at both ends of the reaction plate base plate and fixing holes arranged on the longitudinal support plates, each longitudinal support plate is provided with two fixing holes with full threads passing through the inside, the two fixing holes are longitudinally centered and arranged vertically to the reaction plate base plate, the hole spacing and diameter thereof are consistent with the square rod, and steel wheels are symmetrically provided on the upper and lower parts of the longitudinal support plate, and the space between the upper and lower steel wheels matches the square rod; the two ends of the reaction plate are respectively slidably connected to the upper and lower surfaces of the two square rods through steel wheels, and are fixedly connected to the square rods through bolts, and when the bolts are removed, the reaction plate can slide freely on the square rods.

[0012] The preferred technical solution of the present invention is as follows: the loading support includes a loading base plate and a loading pad, the loading pad is two full-length flat plates at an angle of 90°, rigidly fixed on the loading base plate, a plurality of stiffening ribs are provided between the loading base plate and the loading pad, steel wheels are also symmetrically provided at both ends of the loading support, with an upper and lower group provided on each side, the upper group is symmetrically arranged on the loading pad, and the lower group is arranged on the loading base plate, and the space between the upper and lower groups of steel wheels matches the square rod; the two ends of the loading support are slidably connected to the upper and lower surfaces of the two square rods through steel wheels respectively, and can slide freely along the square rods.

[0013] The present invention also provides a test method for continuous two-end shear loading, wherein the method uses the above-mentioned device for continuous two-end shear loading to perform the test, and the specific steps are as follows:

[0014] S1 Specimen placement: Place the test specimen on the specimen base and install the measurement sensors required for the specimen test before the test;

[0015] S2 Install the test device: Place the outer frame in a spacious position, lock the wheels of the outer frame, install the upper and lower loading frames on the support frame, reserve a position for the loading jack between the loading support and the reaction plate of each loading frame, adjust the distance between the loading support and the reaction plate of the upper and lower loading frames, and then fix the reaction plate; select two long piston loading jacks that match the test, and install a pressure sensor on the top of the jack piston, respectively install the two loading jacks between the loading support and the reaction plate of the upper and lower loading frames through the jack holder, connect the two loading jacks to the electric hydraulic pump, operate the electric hydraulic pump to push the two loading jack pistons out by 5 to 15 mm, and operate the jack holder to fix the two loading jacks to the center of the loading direction;

[0016] S3 initial state of the device: adjust the upper loading frame and the lower loading frame to the two far ends of the support frame and fix them; release the connecting member at the lower end of the support frame, and drive the support frame to rotate upward along the rotating shaft through the hoist lifting mechanism until the support frame is higher than the height of the specimen base and the test specimen, and then stop;

[0017] S4 Push into the test position: release the brake mechanism of the outer frame, push the installed test device along the side of the frame to the outside of the test specimen, and the diagonal line of the test specimen and the outer frame are in the same straight line, then drive the support frame to rotate downward along the shaft to the diagonal line of the outer frame through the winch lifting mechanism, stop the winch lifting mechanism, and connect the support frame to the outer frame through the connecting member; adjust the upper and lower loading frames so that the two loading frames are respectively located at the two diagonal parts of the test specimen and then fix them respectively, then use the loading jack to make the loading support close to the corner of the test specimen, and lock the brake mechanism of the outer frame to limit the outer frame from continuing to move;

[0018] S5 test: the test is carried out in accordance with the specification, the upper and lower loading jacks are adjusted by the hydraulic pump to work simultaneously for loading and unloading operations, and the test data is recorded by the installed pressure sensor, and the shear loading test is carried out on both ends of the test specimen;

[0019] S6 Disassembly test device: After the S5 test is completed, loosen the fixing bolts of the upper loading frame and the lower loading frame, adjust the upper and lower loading frames to move them to the far end of the support frame and fix them, and then drive the support frame to be lifted to a position higher than the test specimen through the winch adjustment mechanism;

[0020] S7 performs the next set of tests: release the brake mechanism of the outer frame, push the outer frame forward to the next test specimen, and repeat steps S4-S6 to complete the shear loading test at both ends of the next test specimen.

[0021] A further technical solution of the present invention is as follows: the test specimen is a masonry specimen which is built in a strip manner and cured on a specimen base, and a plurality of test specimens are arranged in a line or in multiple rows with their short sides facing each other, and are numbered in sequence, and a distance between two adjacent test specimens in the same row is ≥500mm. After the shear loading test at both ends of each test specimen is completed, there is no need to disassemble the device, and the outer frame can be moved to the next adjacent test specimen for a shear loading test.

[0022] The invention is suitable for diagonal shear test research in the professional field of building structure engineering, and the device is designed to address many inconveniences of the specifications and existing in-situ diagonal shear tests.

[0023] The beneficial effects of the present invention are:

[0024] 1. The test device of the present invention comprises a test part and a test frame, wherein the test frame has only an upper part of a short side surface of the frame with an inclined rod support higher than the test piece, and has no other shielding components, so that the test piece can be directly crossed over and operated; the loading device can be raised and lowered by only electrically adjusting a small winch, and the device group with a freely sliding steel wheel can achieve the fitting of the support group to the test piece, and the device is connected to the reaction plate through the full-thread through hole on the square rod by bolts, so that the device can be fixed for subsequent loading; the present invention achieves the purpose of continuous loading, and the operation is simple and convenient, avoiding the complicated process of disassembly and reinstallation when the next test piece is tested after each test is completed, thereby accelerating the test efficiency and saving the test cost.

[0025] 2. The test part in the present invention can realize bidirectional loading. By realizing uniform and synchronous loading at both ends, the influence of accidental factors such as environment and human factors on the test specimen during the test process can be reduced. At the same time, the influence of premature splitting failure caused by additional edge load can also be reduced, thereby improving the accuracy of the test results and the test efficiency. It can provide more comprehensive test research parameters for the reinforcement of old residential areas with tight time and heavy tasks, and has good economic and social benefits.

[0026] 3. The bidirectional loading mechanism in the present invention is connected as a whole through a square rod with holes. The openings on the square rod with holes are full-thread through holes. On the one hand, they provide temporary fixing positions for the upper and lower reaction plates and the upper and lower loading supports before installing the jack and when lifting the rods; on the other hand, the reaction plates are fixed to appropriate holes before the test to provide reaction force during loading; at the same time, the square rod with holes also provides a sliding track for the reaction plates and the loading supports to meet the linearity of the loading direction during loading.

[0027] 4. A protruding wheel rim is provided at the inner edge of the small steel wheel on the loading mechanism of the present invention, which can ensure that the entire device group runs straight along the square rod with holes without deviation during the sliding process. At the same time, a locking device can also be provided on the wheel to facilitate fixing the device group when adjusting the lifting of the square rod with holes.

[0028] 5. The frame of the present invention has universal wheels and is equipped with wheel locks, which makes it easy to carry the test device and quickly move it to the test specimen, ensuring that the frame is in a locked and stable state during the test, avoiding the phenomenon of manually lifting the device accessories to the test site, saving labor costs, and improving the test speed.

[0029] 6. The test device of the present invention adopts an integrated mode. Before the test, it is only necessary to replace the loading jack with the required accuracy. The device is equipped with a jack fixer to prevent the jack from shifting during loading and unloading, thereby improving the test accuracy.

[0030] 7. During the test process of the present invention, at the end of each test, the fixing bolts on the square rod are removed, the sliding device is assembled to the two ends of the square rod, and the electric adjustment small winch is used to lift the test device until it is higher than the test piece. By reasonably designing the test pieces arranged in a "straight line", the entire test frame device is pushed forward to the second test piece, and after the test, it continues to move forward and so on until all the test pieces are completed. In this process, only the sliding device group and the electric small winch are required, and other test devices do not need to be adjusted too much, which saves time and effort, and also avoids differences in test conditions of the same group of test pieces due to each loading and unloading of the test device.

[0031] The present invention can reduce the influence of accidental factors such as environment and human factors on the test specimens during the test process by realizing two-end loading and continuous loading, thereby improving the accuracy of the test results and the test efficiency. It can provide more comprehensive test research parameters for studies such as reinforcement of old residential areas with tight time and heavy tasks, and has good economic and social benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 is a front view of the overall device of the present invention;

[0033] Figure 2 yes Figure 1 A magnified schematic diagram of the middle part;

[0034] Figure 3 is a side view of the overall device of the present invention;

[0035] Figure 4 is a top view of the loading reaction plate of the present invention;

[0036] Figure 5 is a side view of the loading reaction plate of the present invention

[0037] Figure 6 It is a structural schematic diagram of the jack fixer of the present invention;

[0038] Figure 7 is a front view of a loading support of the present invention;

[0039] Figure 8 is a top view of a loading support of the present invention;

[0040] Fig. 9 is a side view of a loading support of the present invention;

[0041] Fig.10 It is a schematic diagram of the state in which the device group of the present invention is pushed into the two ends of the square rod with holes;

[0042] Fig.11 It is a schematic diagram of the square rod with holes and the device group of the present invention in the lifting state;

[0043] Fig.12It is a schematic diagram of the whole set of device structure of the present invention being pushed into the next test piece;

[0044] Fig.13 It is a schematic diagram of the test process of the present invention;

[0045] Fig.14 It is a schematic diagram of the test flow in the embodiment.

[0046] In the figure: 1—external frame, 100—square frame body, 101—first cross bar, 102—diagonal support bar, 103—universal wheel, 104—brake mechanism, 2—support frame, 200—rotating shaft, 201—connecting member, 2011—support bar, 2012—slot, 202—bolt hole, 203—second cross bar, 204—square bar, 3—upper loading frame, 300—reaction plate, 3001—reaction plate bottom plate, 3002—transverse stiffening rib, 3003—longitudinal support plate, 3004—fixing hole, 301—loading support, 3011—loading bottom plate, 3012—loading pad, 3013—loading support, 3014—loading base plate, 3015—loading pad, 3016—loading base plate, 3017—loading base plate, 3018—loading base plate, 3019—loading base plate, 3020—loading base plate, 3021—loading base plate, 3023—loading base plate, 3024—loading base plate, 3025—loading base plate, 3026—loading base plate, 3027—loading base plate, 3028—loading base plate, 3029—loading base plate, 3030—loading base plate, 3031—loading base plate, 3032—loading base plate, 3033—loading base plate, 3034—loading base plate, 3035—loading base plate, 3036—loading base plate, 3037—loading base plate, 3038—loading base plate, 3039—loading base plate, 3040—loading base plate, 3041—loading base plate, 3042—loading base plate, 30 —Stiffening rib plate, 4—lower loading frame, 5—electric hydraulic pump, 6—upper loading jack, 7—lower loading jack, 8—jack holder, 800—arc-shaped clamping plate, 801—screw rod, 802—rotating handle, 9—wire rope, 10—test specimen, 11—winch, 12—pulley, 13—specimen base, 14—main oil pipe, 15—oil distributor, 16—oil distribution pipe, 17—steel wheel, 18—bolt, 19—pressure sensor, 20—fixing plate. DETAILED DESCRIPTION

[0047] The present invention will be further described below in conjunction with the accompanying drawings and embodiments. Figures 1 to 14 The drawings are all of embodiments, which are drawn in a simplified manner and are only used for the purpose of clearly and concisely illustrating the embodiments of the present invention. The technical solutions shown in the following drawings are specific solutions of the embodiments of the present invention and are not intended to limit the scope of the invention claimed for protection. 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.

[0048] In the description of the present invention, it should be understood that the terms "upper", "lower", "inside", "outside", "left", "right", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships conventionally placed when the invention is used, or are the orientations or positional relationships conventionally understood by those skilled in the art. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0049] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms such as "disposed" and "connected" should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0050] The test specimen 10 in the embodiment is a square specimen with a side length of 900 to 1200 mm and a thickness of 200 to 250 mm; a test device for continuous two-end shear loading used in the embodiment, such as Figures 1 to 3 As shown, the test device includes a square outer frame 1 of the same shape as the test specimen 10, a bidirectional loading bracket, a hydraulic loading device, a winch lifting mechanism and a specimen base 13. The height of the specimen base 13 is 900-1100 mm, and the length of the specimen base 13 is 180-210 mm less than the length of the test specimen 10. Generally, about 200 mm is reserved for the convenience of installing the loading device. The outer frame 1 includes two parallel square frames 100, one side of the top of the two square frames 100 is connected as a whole by a first cross bar 101, and the other side is connected by a rotating shaft 200. A diagonal brace 102 is provided on the upper part of one side of the two square frames 100 connected by the rotating shaft 200. The height of the diagonal brace 102 is higher than the total height of the test specimen 10 and the specimen base 13. Universal wheels 103 are respectively provided at the bottom of the two square frames 100. Each universal wheel 103 has a brake mechanism 104. The universal wheel 103 is used to carry the test device. The brake mechanism 14 can be a wheel lock installed on the upper part of the universal wheel 103 to lock the frame movement during the test. The length and width of the outer frame 1 are set according to the size of the test specimen 10 to facilitate the test.

[0051] A test device for continuous two-end shear loading used in the embodiment, such as Figures 1 to 3As shown, the bidirectional loading bracket includes a supporting frame 2 arranged along the diagonal line of the outer frame 1 and an upper loading frame 3 and a lower loading frame 4 respectively mounted on the supporting frame 2. The upper loading frame 3 and the lower loading frame 4 both include a reaction plate 300 and a loading support 301, the reaction plate 300 is fixedly mounted on the support frame 2, and the loading support 301 is slidably connected to the support frame 2; the hydraulic loading device includes an electric oil pressure pump 5, an upper loading jack 6 and a lower loading jack 7, the upper loading jack 6 and the lower loading jack 7 are respectively mounted on the upper loading frame 3 and the lower loading frame 4 through jack holders 8, and the jack holders 8 on each loading frame are provided with two groups, which are respectively connected to the reaction plate 300 and the loading support 301; the electric oil pressure pump 5 is connected to the oil distributor 15 through the main oil pipe 14, and the oil distributor is respectively connected to the upper loading jack 6 and the lower loading jack 7 through two oil distribution pipes 16, and provides hydraulic power for the upper loading jack 6 and the lower loading jack 7, so as to realize the synchronous actuation of the upper loading jack 6 and the lower loading jack 7, and a pressure sensor 19 is installed at the top position of the piston end of each jack. During the loading test, the test specimen 10 is placed on the specimen base 13, the outer frame 1 is located outside the test specimen 10 and the specimen base 13, and the diagonal line of the outer frame 1 is in the same straight line as the diagonal line of the test specimen 10. The two loading frames 3 are located at the two diagonal parts of the test specimen 10, and are in close contact with the corners of the test specimen 10 through the loading supports 301. Figure 6 As shown, each set of jack fixtures 8 includes two symmetrically arranged arc-shaped clamping plates 800 and a screw rod 801 for fixing each arc-shaped clamping plate 800. At least two fixing plates 20 with thread holes are correspondingly welded on the reaction plate 300 and the loading support 301. A rotating handle 802 is provided at one end of the screw rod 801, and the thread on the screw rod 801 matches the inner thread of the thread hole on the fixing plate 20. When the upper loading jack 6 and the lower loading jack 7 are installed, the jack is placed between the reaction plate 300 and the loading support 301, and the two sets of jack fixtures 8 are respectively placed on the piston end and the cylinder end of the jack to be installed. The two arc-shaped clamping plates 800 of each set of jack fixtures are symmetrically clamped on the outside of the jack, and each arc-shaped clamping plate 800 is connected to the outside of the jack by the screw rod 801. After passing through the corresponding fixed plate 20, the jack is tightened and fixed. When the screw rod 801 rotates, the arc-shaped clamping plate 800 maintains the original position and rotates asynchronously. The arc-shaped clamping plate 800 is perpendicular to the jack cylinder body and must include the jack cylinder body to support the jack and limit its lateral displacement during installation and testing, ensuring that the overall test device is in a linear state.

[0052] A test device for continuous two-end shear loading used in the embodiment, such as Figures 1 to 3As shown, the support frame 2 includes two symmetrical square rods 204, each of which is provided with a plurality of bolt holes 202, and the plurality of bolt holes 202 are equidistantly distributed on the side of the square rod 204, and the internal thread runs through the rod member, and the diameter and hole spacing of the bolt hole 202 are both 20-40 mm, which are used to bolt the reaction plate of the loading frame to facilitate the fixing of the reaction plate 300; one end of the two square rods 204 is installed at one of the top corners of the square frame body 100 through the rotating shaft 200, and the other end is connected by the second cross bar 203, and the ends of the two square rods 204 provided with the second cross bar 203 are connected to the diagonal parts of the square frame body 100 through the connecting member 201; the connecting member 201 includes a groove 2012 arranged at the ends of the two square rods 204 and a support rod 2011 arranged on the outer frame 1, and when the support frame 2 is rotated along the rotating shaft 200 to the diagonal line of the outer frame 1, the support frame 2 The hoisting mechanism comprises a hoisting machine 11, a pulley 12 and a lifting wire rope 9. The hoisting machine 11 and the pulley 12 are installed on the top of the outer frame 1. One end of the lifting wire rope 9 is connected to the hoisting machine 11 and connected to the middle part of the second cross bar 203 around the pulley 12, and drives the support frame 2 to rotate up and down in the outer frame 1 along the rotating shaft 200 (such as Figures 10 to 12 ).

[0053] The reaction plate 300 in the embodiment is as follows: Figure 4 and Figure 5 As shown, it includes a reaction plate bottom plate 3001, transverse stiffening ribs 3002, longitudinal support plates 3003 arranged at both ends of the reaction plate bottom plate 3001, and fixing holes 3004 arranged on the longitudinal support plates 3003. Each longitudinal support plate 3003 is provided with two fixing holes 3004 with full threads passing through the inside. The two fixing holes 3004 are arranged vertically in the center of the reaction plate bottom plate 3001, and the hole spacing and diameter thereof are consistent with the square rod 204. Steel wheels 17 are symmetrically arranged on the upper and lower sides of the longitudinal support plates 3003, and the space between the upper and lower steel wheels 17 matches the square rod 204. The two ends of the reaction plate 300 are respectively slidably connected to the upper and lower surfaces of the two square rods 204 through the steel wheels 17, and can move along the square rods 204. After moving to a certain position, it can be fixedly connected to the square rods 204 by bolts 18. The loading support 301 is as shown in Figures 7 to 9As shown, it includes a loading base plate 3011 and a loading pad 3012. The loading pad 3012 is two full-length flat plates at 90°, rigidly fixed on the loading base plate 3011, and the loading pad 3012 can just clamp the corner of the main test specimen 10. A plurality of stiffening ribs 3013 are arranged between the loading base plate 3011 and the loading pad 3012. Steel wheels 17 are also symmetrically arranged at both ends of the loading support 301, and two groups are arranged on each side. The upper group is symmetrically arranged on the loading pad 3012, and the lower group is arranged on the loading base plate 3011. The space between the upper and lower groups of steel wheels 17 matches the square rod 204; the two ends of the loading support 301 are respectively connected to the upper and lower surfaces of the two square rods 204 through the steel wheels 17, and can slide freely along the square rods 204. The loading support 301 is arranged at the two diagonal loading positions of the test specimen 10, and can slide freely on the square rods 204 when there is no constraint, which is convenient for loading.

[0054] When the present invention is used, a plurality of test specimens can be subjected to a shear loading test in succession, wherein the test specimens are arranged in a line with their short sides facing each other, such as Fig.13 As shown, the specimen base should be arranged with the notch of the specimen facing the test direction. The short side spacing of the specimen should be a ≥ 500mm. Multiple rows of specimens (200) can be set according to the actual needs of the test, and the spacing between each row should be b ≥ 1200mm, so as to facilitate the test installation and observation of test phenomena. All specimens are named in sequence from near to far according to the distance from the starting test position, 1A~1Z, 2A~2Z, and so on. They can also be named flexibly according to the actual test. Each test only needs to move the frame (100).

[0055] The test method of the present invention is further described below in conjunction with a specific embodiment. In the embodiment, a masonry specimen is taken as an example, and the above-mentioned test device for continuous shear loading at both ends is used to continuously perform shear loading tests on multiple test specimens. The test specimens in the embodiment are a set of test specimens with reinforced surface variables, all of which are brick-laid square specimens with a side length of 1200mm and a thickness of 240mm when not reinforced. The strength of the masonry mortar is M2.5, and the arrangement is as follows: Fig.14 As shown, a total of 4 rows are divided, with 25 and 100 pieces in each row as an example; the specific test steps are as follows:

[0056] S1 Specimen placement: Taking masonry specimens as an example, the specimens are laid in strips and cured on the specimen base. The specimens are named 1A~1Y to 4A~4Y. The lateral spacing of the specimens is a=500mm, and the row spacing is b=1200mm. The measuring sensors required for the specimen test are installed before the test.

[0057] S2 Install the test device: Place the outer frame 1 in a spacious position, lock the wheel locks, install the loading support 301 and the reaction plate 300 of the upper loading frame 3 and the lower loading frame 4 on the square rod 204 respectively, place the steel wheels 17 of the loading support 301 and the reaction plate 300 on the upper and lower surfaces of the square rod 204, and allow them to slide up and down along the square rod 204 under the action of external force, and fasten the reaction plate 300 through the bolts 18. Fix, and reserve space for the loading jack between the loading support 301 and the reaction plate 300; then select two long piston loading jacks that match the test, install a pressure sensor at the top of each jack piston, and finally install the upper loading jack 6 between the loading support and the reaction plate of the upper loading frame 3, and install the lower loading jack 7 between the loading support and the reaction plate of the lower loading frame 4, operate the oil pump to push the loading jack piston top 10mm, and operate the jack holders 8 of the upper and lower loading jacks to fix the loading jacks to the center of the loading direction.

[0058] S3 initial state of the device: move the upper loading frame 3 and the lower loading frame 4 equipped with loading jacks to the two ends of the square rod 204 respectively, and fix and lock the reaction plate 300 of each loading frame by bolts 18; adjust the winch 11 to tighten the wire rope 9 around the pulley 12, lift the support frame 2 and the loading frame installed on the support frame 2 to rotate around the rotating shaft 200, and when the support frame 2 is higher than the total height of the test specimen 10 and the specimen base 13, suspend the work of the winch 11.

[0059] S4 Push into the test position: unlock the wheel lock of the outer frame 1 to make it unlocked, as shown in Figure 11, push the above-installed frame and loading device assembly along the side of the frame to the position of the test specimen 1A; then adjust the winch 11 to lower the support frame 2, and stop the winch when the support frame 2 is at the diagonal position on both sides of the test specimen 10. Fig.10 As shown, the groove 2012 at the bottom of the support frame 2 is clamped on the support rod 2011 on the outer frame 1, and the bottom of the surface support frame 2 is in an active state; then the reaction plate fixing bolts of the upper loading frame 3 and the lower loading frame 4 are loosened, and the upper loading frame 3 can slide freely by gravity to approach the upper diagonal of the test specimen 10, and the lower loading frame 4 is pushed upward to make it close to the lower diagonal of the test specimen 10. After the upper and lower loading frames are close to the two diagonals, they are fixed and locked by bolts 18 respectively, and the upper and lower download jacks are adjusted to push so that the loading support 301 is close to the test specimen 10, and then the wheel lock is adjusted to be in a locked state to limit the movement of the frame.

[0060] S5 performs the test: the test is performed in accordance with the specification, the upper and lower jacks are adjusted by the electric hydraulic pump 5 to work simultaneously to perform loading and unloading operations, the test data is recorded by the installed pressure sensor 19, etc., and the shear loading test at both ends of the test specimen 1A is completed.

[0061] S6 Disassembly test device: After the S5 test is completed, remove the bolts 18 of the upper and lower loading frames, move the upper and lower loading frames to the two far ends of the square rod respectively, and fix them with bolts, and adjust the winch 11 to lift the square rod and the auxiliary device group.

[0062] S7 carries out the next set of tests: Fig.12 As shown, push the test device forward to the test specimen 1B, repeat steps S4-S6 to perform the shear loading test on the test specimen 1B; then repeat the above test steps until all the specimens 1A to 1Y in the first row are completed, and push the test device to the position of the test specimen 2A in the second row, and repeat the above steps to complete the loading tests of the second, third and fourth rows in sequence.

[0063] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation modes, which are merely illustrative rather than restrictive. Under the guidance of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the present invention and the claims, all of which are within the protection of the present invention.

Claims

1. A test device for continuous two-end shear loading, which performs a shear loading test on a square test specimen, characterized in that: The test device comprises a square outer frame (1) of the same shape as the test specimen (10), a bidirectional loading bracket, a hydraulic loading device, a winch lifting mechanism and a specimen base (13); the bidirectional loading bracket comprises a support frame (2) arranged along the diagonal of the outer frame (1) and an upper loading frame (3) and a lower loading frame (4) respectively mounted on the support frame (2); one end of the support frame (2) is mounted on one of the top corners of the square frame body (100) via a rotating shaft (200), and the other end is provided with a connecting member (201) fixed to the diagonal of the top corner; the winch lifting mechanism is mounted on the top of the outer frame (1) and connected to the support frame (2) via a steel wire rope (9); and when the connecting member (201) is not fixed, the winch lifting mechanism drives the support frame (2) to rotate up and down along the rotating shaft (200); the upper loading frame (3) and the lower loading frame (4) both comprise a reaction plate (300) and a loading support (301); the reaction plate (300) is fixedly mounted On the support frame (2), a loading support (301) is slidably connected to the support frame (2); the hydraulic loading device comprises an oil pressure pump (5), an upper loading jack (6) and a lower loading jack (7); the upper loading jack (6) and the lower loading jack (7) are respectively mounted on the upper loading frame (3) and the lower loading frame (4) via a jack fixture (8); the oil pressure pump (5) is respectively connected to the upper loading jack (6) and the lower loading jack (7) via an oil pipe, and is used for the upper loading jack The top (6) and the lower loading jack (7) provide hydraulic power; during the loading test, the test specimen (10) is placed on the specimen base (13), the outer frame (1) is located outside the test specimen (10) and the specimen base (13), and the diagonal line of the outer frame (1) and the diagonal line of the test specimen (10) are on the same straight line, and the two loading frames (3) are located at two diagonal positions of the test specimen (10), and are in close contact with the corners of the test specimen (10) through the loading supports (301); The support frame (2) comprises two symmetrical square rods (204), and the reaction plate (300) comprises a reaction plate bottom plate (3001), a transverse stiffening rib (3002), longitudinal support plates (3003) arranged at both ends of the reaction plate bottom plate (3001), and fixing holes (3004) arranged on the longitudinal support plates (3003), each longitudinal support plate (3003) being provided with two fixing holes (3004) with full threads passing through the inside, and the two fixing holes (3004) being centered longitudinally and perpendicular to the reaction plate bottom plate (3001). 001), the hole spacing and diameter thereof are consistent with those of the square rod (204), and steel wheels (17) are symmetrically arranged on the upper and lower sides of the longitudinal support plate (3003), and the space between the upper and lower steel wheels (17) matches the square rod (204); the two ends of the reaction plate (300) are respectively slidably connected to the upper and lower sides of the two square rods (204) through the steel wheels (17), and are fixedly connected to the square rod (204) through bolts (18), and when the bolts (18) are removed, the reaction plate (300) can slide freely on the square rod (204); The loading support (301) comprises a loading base plate (3011) and a loading pad plate (3012). The loading pad plate (3012) is two full-length flat plates at an angle of 90 degrees, which are rigidly fixed on the loading base plate (3011). A plurality of stiffening rib plates (3013) are provided between the loading base plate (3011) and the loading pad plate (3012). Steel wheels (17) are also symmetrically provided at both ends of the loading support (301), with two groups of steel wheels (17) provided on each side. The upper group is symmetrically provided on the loading pad plate (3012), and the lower group is provided on the loading base plate (3011). The space between the upper and lower groups of steel wheels (17) matches the square rod (204). The two ends of the loading support (301) are respectively connected to the upper and lower surfaces of the two square rods (204) by sliding, and can slide freely along the square rods (204).

2. A test device for continuous two-end shear loading according to claim 1, characterized in that: The test specimen (10) is a square specimen with a side length of 900-1200 mm and a thickness of 200-250 mm; the specimen base (13) has a height of 900-1100 mm, and the length of the specimen base (13) is 180-210 mm less than the length of the test specimen (10); the outer frame (1) comprises two parallel square frame bodies (100), the tops of the two square frame bodies (100) are connected as a whole via a first crossbar (101) on one side, and are connected via a rotating shaft (200) on the other side; an oblique support rod (102) is provided on the upper part of one side of the two square frames (100) connected via the rotating shaft (200), the oblique support rod (102) being arranged at a height higher than the total height of the test specimen (10) and the specimen base (13); universal wheels (103) are provided at the bottoms of the two square frame bodies (100), and each universal wheel (103) is provided with a brake mechanism (104).

3. A test device for continuous two-end shear loading according to claim 1 or 2, characterized in that: Each square rod (204) is provided with a plurality of bolt holes (202), and the plurality of bolt holes (202) are equidistantly distributed on the side of the square rod (204), and the inside of the square rod is fully threaded through the rod member, and the diameter and hole spacing of the bolt holes (202) are both 20-40 mm; one end of the two square rods (204) is installed at one of the top corners of the square frame body (100) through a rotating shaft (200), and the other end is connected through a second cross bar (203), and the two square rods (204) are provided with the end of the second cross bar (203) connected through a connecting member (20 1) is connected to the diagonal part of the square frame body (100); the hoist lifting mechanism is connected to the middle part of the second cross bar (203) through a steel wire rope (9); the connecting member (201) comprises a lap groove (2012) provided at the ends of two square bars (204) and a support rod (2011) provided on the outer frame (1); when the support frame (2) rotates along the rotating shaft (200) to the diagonal line of the outer frame (1), the support frame (2) is lapped on the support rod (2011) through the lap groove (2012) at its end.

4. A test device for continuous two-end shear loading according to claim 1 or 2, characterized in that: The hoist lifting mechanism comprises a hoist (11), a pulley (12) and a lifting wire rope (9); the hoist (11) and the pulley (12) are mounted on the top of the outer frame (1); one end of the lifting wire rope (9) is connected to the hoist (11) and is connected to one end of a connecting member (201) provided on a support frame (2) around the pulley (12), and drives the support frame (2) to rotate up and down along a rotating shaft (200) in the outer frame (1).

5. A test device for continuous two-end shear loading according to claim 1 or 2, characterized in that: The hydraulic pump (5) is an electric hydraulic pump. The hydraulic pump (5) is connected to an oil distributor (15) via a main oil pipe (14). The oil distributor is respectively connected to an upper loading jack (6) and a lower loading jack (7) via two oil distribution pipes (16) for achieving synchronous actuation of the upper loading jack (6) and the lower loading jack (7). A pressure sensor (19) is installed at the top of the piston end of each jack.

6. A test device for continuous two-end shear loading according to claim 1 or 2, characterized in that: The jack fixture (8) is provided with two groups, which are respectively connected to the reaction plate (300) and the loading support (301), each group of the jack fixture (8) comprises two symmetrically arranged arc-shaped clamping plates (800) and a screw rod (801) corresponding to each arc-shaped clamping plate (800), at least two fixing plates (20) with thread holes are welded to the reaction plate (300) and the loading support (301), one end of the screw rod (801) is provided with a rotating handle (802), and the thread on the screw rod (801) is in contact with the fixing The internal threads of the thread holes on the fixed plate (20) match each other; when the upper loading jack (6) and the lower loading jack (7) are installed, the jack is placed between the reaction plate (300) and the loading support (301), and the two sets of jack fixtures (8) are respectively placed on the piston end and the cylinder end of the jack to be installed, and the two arc-shaped clamping plates (800) of each set of jack fixtures are symmetrically clamped on the outside of the jack, and each arc-shaped clamping plate (800) passes through the corresponding fixed plate (20) through the screw rod (801) and then tightens and fixes the jack.

7. A test method for continuous two-end shear loading, characterized in that: The method uses the device for continuous two-end shear loading as described in any one of claims 1 to 6 to conduct a test, and the specific steps are as follows: S1 Specimen placement: Place the test specimen on the specimen base and install the measurement sensors required for the specimen test before the test; S2 Install the test device: place the outer frame in a spacious position, lock the wheels of the outer frame, install the upper and lower loading frames on the support frame, reserve a position for the loading jack between the loading support and the reaction plate of each loading frame, adjust the distance between the loading support and the reaction plate of the upper and lower loading frames, and then fix the reaction plate; select two long piston loading jacks that match the test, and install a pressure sensor on the top of the jack piston, respectively install the two loading jacks between the loading support and the reaction plate of the upper and lower loading frames through the jack holder, connect the two loading jacks to the electric hydraulic pump, operate the electric hydraulic pump to push the two loading jack pistons out by 5~15mm respectively, and operate the jack holder to fix the two loading jacks to the center of the loading direction; S3 initial state of the device: adjust the upper loading frame and the lower loading frame to the two far ends of the support frame and fix them; release the connecting member at the lower end of the support frame, and drive the support frame to rotate upward along the rotating shaft through the hoist lifting mechanism until the support frame is higher than the height of the specimen base and the test specimen, and then stop; S4 Push into the test position: release the brake mechanism of the outer frame, push the installed test device along the side of the frame to the outside of the test specimen, and the diagonal line of the test specimen and the outer frame are in the same straight line, then drive the support frame to rotate downward along the shaft to the diagonal line of the outer frame through the winch lifting mechanism, stop the winch lifting mechanism, and connect the support frame to the outer frame through the connecting member; adjust the upper and lower loading frames so that the two loading frames are respectively located at the two diagonal parts of the test specimen and then fix them respectively, then use the loading jack to make the loading support close to the corner of the test specimen, and lock the brake mechanism of the outer frame to limit the outer frame from continuing to move; S5 test: the test is carried out in accordance with the specification, the upper and lower loading jacks are adjusted by the hydraulic pump to work simultaneously for loading and unloading operations, and the test data is recorded by the installed pressure sensor, and the shear loading test is carried out on both ends of the test specimen; S6 Disassembly test device: After the S5 test is completed, loosen the fixing bolts of the upper loading frame and the lower loading frame, adjust the upper and lower loading frames to move them to the far end of the support frame and fix them, and then drive the support frame to be lifted to a position higher than the test specimen through the winch adjustment mechanism; S7 performs the next set of tests: release the brake mechanism of the outer frame, push the outer frame forward to the next test specimen, and repeat steps S4-S6 to complete the shear loading test at both ends of the next test specimen.

8. A test method for continuous two-end shear loading according to claim 7, characterized in that: The test specimen is a masonry specimen built in a strip manner and cured on a specimen base. Multiple test specimens are arranged in a line or in multiple rows with their short sides facing each other, and are numbered in sequence. The distance between two adjacent test specimens in the same row is ≥500mm. After the shear loading test at both ends of each test specimen is completed, there is no need to disassemble the device, and the outer frame can be moved to the next adjacent test specimen for a shear loading test.

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