A flexural testing system for high-performance concrete

Abstract

This invention relates to the field of concrete performance testing technology, specifically to a flexural testing system for high-performance concrete. The system includes a first base and a hydraulic drive component, which drives the first base to slide vertically. Two upper clamping rollers are located at the bottom of the first base. A second base is located below the first base. Two mounting seats are located on the top of the second base. Each mounting seat has a lower clamping roller and a bidirectional spiral shaft at its top. The bidirectional spiral shaft can rotate around its own axis and has two spiral grooves with opposite directions of rotation. Each spiral groove has a positioning part that is screwed into it. When positioning the high-performance concrete sample, the rotation of the bidirectional spiral shaft causes the two positioning parts on the same shaft to move closer together, thereby achieving positioning of the high-performance concrete sample in the width direction and improving the accuracy of the bending test results.

Description

Technical Field

[0001] This invention relates to the field of concrete performance testing technology, and in particular to a flexural testing system for high-performance concrete. Background Technology

[0002] High-performance concrete, as a new type of building material, has been widely used in many fields such as building construction, road and bridge construction, and marine engineering due to its comprehensive advantages of high strength, high durability, high workability and high volume stability.

[0003] Since the performance of high-performance concrete is directly related to the safety and durability of engineering structures, rigorous testing of various data before its use is a key step to ensure that it meets the requirements for actual use; among them, the flexural performance test is particularly important; and testing equipment is required when testing the flexural performance of high-performance concrete.

[0004] In related technologies, such as Chinese patent CN220063686U, a device for testing the compressive and flexural strength of cement concrete samples is disclosed. This device includes a test platform equipped with a hydraulic drive, a long plate, and an upper clamping roller. The hydraulic drive is used to drive the long plate to rise and fall, and a lower clamping roller is fixed on the long plate. In use, the concrete sample is first placed on top of the lower clamping roller. Then, the hydraulic drive is activated, moving the concrete sample so that it contacts the upper clamping roller. As the hydraulic drive continues to operate, the concrete sample is bent by the upper and lower clamping rollers. The change in hydraulic pressure of the hydraulic drive is monitored by relevant software. When the concrete sample breaks, the hydraulic drive is deactivated, thus achieving the flexural strength test of the concrete sample.

[0005] However, when testing concrete samples using existing flexural strength testing devices, the concrete sample and the lower clamping roller may be misaligned in the width direction, causing the stress state of the concrete sample to deviate from the stress state under standard testing conditions, which will affect the accuracy of the bending test results. Summary of the Invention

[0006] Therefore, it is necessary to provide a high-performance concrete flexural properties testing system to address the problem of low accuracy in current concrete flexural properties testing devices.

[0007] The above objectives are achieved through the following technical solutions:

[0008] A flexural strength testing system for high-performance concrete, the system being configured to perform flexural strength testing on high-performance concrete samples, the high-performance concrete samples being cuboid in shape.

[0009] The high-performance concrete flexural strength testing system includes a first base that can slide vertically; two upper clamping rollers are provided at the bottom of the first base, the upper clamping rollers being parallel to the width direction of the high-performance concrete sample, the two upper clamping rollers being spaced apart and symmetrically arranged about the first base; a second base is provided below the first base; two mounting seats are provided at the top of the second base, the two mounting seats being spaced apart along the length direction of the high-performance concrete sample; a lower clamping roller is provided at the top of each mounting seat, the lower clamping rollers being parallel to the upper clamping rollers, the two lower clamping rollers being spaced apart and symmetrically arranged about the first base; a bidirectional spiral shaft is also provided at the top of each mounting seat, the bidirectional spiral shaft being parallel to the lower clamping rollers, the bidirectional spiral shaft being rotatable about its own axis, each bidirectional spiral shaft having two spiral grooves with opposite directions of rotation, each spiral groove having a positioning part screwed into it, the two positioning parts being symmetrically arranged about the first base, the positioning parts being configured to position the high-performance concrete sample along the width direction; after positioning the high-performance concrete sample, the positioning parts disengage from the high-performance concrete sample.

[0010] Furthermore, the two mounting seats can slide synchronously in opposite directions along a direction parallel to the length of the high-performance concrete sample; the high-performance concrete flexural strength testing system also includes a sliding component and an adjusting component, the sliding component being configured to drive the two mounting seats to slide; the adjusting component being configured to drive the two positioning parts away from each other after the two lower clamping rollers have moved into position, without changing the position of the bidirectional spiral shaft.

[0011] Furthermore, the sliding assembly includes a gear and a rack, with the gear sleeved on each of the bidirectional helical shafts; the rack extends along the direction parallel to the length of the high-performance concrete sample and meshes with the gear.

[0012] Further, the adjusting assembly includes a wedge-shaped seat and a sliding shaft, with a third base disposed below the second base; the second base is disposed on the third base and can slide elastically in the vertical direction, forming a stop engagement with the third base; the gear and the bidirectional spiral shaft are connected by a keyway, and the keyways are clearance-fitted; a first elastic element is connected between each gear and the bidirectional spiral shaft, the elastic force direction of the first elastic element being configured to make the relative position of the gear and the bidirectional spiral shaft in the circumferential direction remain unchanged; the wedge-shaped seat is disposed on the third base and forms an inclined guide engagement with the third base; a second elastic element is connected between the wedge-shaped seat and the third base, the elastic force direction of the second elastic element being configured to make the wedge-shaped seat tend to move towards the high-performance concrete sample; the rack is disposed on the wedge-shaped seat; the sliding shaft is simultaneously disposed through the second base, the third base, and the wedge-shaped seat, and can slide in the vertical direction, the sliding shaft and the lower clamping roller being arranged parallel to each other.

[0013] Furthermore, the number of gears is set to four, with two gears sleeved at both ends of one of the bidirectional helical shafts and the other two gears sleeved at both ends of the other bidirectional helical shaft; the number of wedge seats is set to two, and the two wedge seats are arranged at intervals along the width direction of the high-performance concrete sample; the number of racks is set to two, and the two racks respectively mesh with the two gears located on the same side.

[0014] Furthermore, there are two sliding shafts, which are arranged at intervals along the length of the high-performance concrete specimen.

[0015] Furthermore, the first elastic element is a torsion spring.

[0016] Furthermore, the second elastic element is a first compression spring, which is sleeved on the sliding shaft.

[0017] Furthermore, a handwheel is fitted onto each of the bidirectional spiral shafts.

[0018] Furthermore, the high-performance concrete flexural strength testing system also includes a hydraulic drive configured to provide a driving force for sliding the first base.

[0019] The beneficial effects of this invention are:

[0020] This invention relates to a flexural strength testing system for high-performance concrete. By setting up a bidirectional spiral shaft and clamping parts, when positioning the high-performance concrete sample, the two positioning parts on the same bidirectional spiral shaft move closer to each other through the rotation of the bidirectional spiral shaft, thereby moving the high-performance concrete sample in the width direction to align with the upper and lower clamping rollers. This avoids the impact on the accuracy of bending test results caused by the lack of a width-direction positioning mechanism when subsequently performing flexural strength testing on the high-performance concrete sample.

[0021] Furthermore, by setting two mounting seats, the two lower clamping rollers can slide synchronously in opposite directions along a direction parallel to the length of the high-performance concrete sample. During use, the distance between the two lower clamping rollers can be adjusted adaptively according to the length of the high-performance concrete sample, thereby meeting the testing requirements of high-performance concrete samples of different lengths and improving the application range of the system. Attached Figure Description

[0022] Figure 1 A three-dimensional structural schematic diagram of the high-performance concrete flexural properties testing system provided in an embodiment of the present invention;

[0023] Figure 2 for Figure 1 A magnified view of the structure at point A in the middle;

[0024] Figure 3 A top view of the flexural properties testing system for high-performance concrete provided in an embodiment of the present invention;

[0025] Figure 4 for Figure 3 Sectional view along the BB direction;

[0026] Figure 5 for Figure 4 A magnified schematic diagram of the structure at point C in the middle;

[0027] Figure 6 for Figure 3 DD-direction cross-sectional view;

[0028] Figure 7 for Figure 6 A magnified schematic diagram of the structure at point E in the middle;

[0029] Figure 8 This is a front view structural schematic diagram of the high-performance concrete flexural properties testing system provided in an embodiment of the present invention;

[0030] Figure 9 for Figure 8 Sectional view along the FF direction;

[0031] Figure 10 This is a side view of the flexural properties testing system for high-performance concrete provided in an embodiment of the present invention.

[0032] in:

[0033] 1. First base; 101. Upright pole;

[0034] 2. Upper clamping roller;

[0035] 3. Second base; 301. Second slide groove; 302. Blocking block;

[0036] 4. Mounting base; 401. First slide groove;

[0037] 5. Lower clamping roller;

[0038] 6. Double-sided helical shaft;

[0039] 7. Positioning section;

[0040] 8. Sliding assembly; 801. Gear; 8011. First mounting slot; 802. Rack;

[0041] 901, Third base; 9011, Second compression spring; 9012, Top block; 9013, Guide post; 9014, Wedge strip; 9015, Mounting plate; 90151, Third slide groove; 902, Torsion spring; 903, Wedge seat; 904, First compression spring; 905, Sliding shaft;

[0042] 10. Handwheel;

[0043] 11. Bearing housing;

[0044] 12. Key;

[0045] 13. Fixing bolts. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below through embodiments and in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0047] The component designations used in this document, such as "first" and "second," are merely for distinguishing the described objects and do not have any sequential or technical meaning. The terms "connection" and "linkage," unless otherwise specified, include both direct and indirect connections (linkages). In the description of this invention, it should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the invention.

[0048] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0049] The following reference Figures 1 to 10 This invention describes a flexural strength testing system for high-performance concrete. The system is configured to test the flexural strength of high-performance concrete samples. The high-performance concrete samples are cuboid in shape, and this geometry gives the samples both a length direction and a width direction.

[0050] The flexural strength testing system for high-performance concrete is configured to include a first base 1 and a second base 3. The bottom of the first base 1 is equipped with two upper clamping rollers 2, which are perpendicular to the width direction of the high-performance concrete sample. During use, the upper clamping rollers 2 press against the top of the high-performance concrete sample, ensuring pressure is applied to the top of the sample from top to bottom. The second base 3 is located below the first base 1, and its top is equipped with two mounting seats 4, which are spaced apart along the length of the high-performance concrete sample. Each mounting seat 4 has a lower clamping roller 5 on its top, which is parallel to the upper clamping rollers 2. During use, the lower clamping roller 5 pushes against the bottom of the high-performance concrete sample, ensuring both support and upward pressure on the bottom of the sample when the upper clamping rollers 2 press against it.

[0051] Two upper clamping rollers 2 are arranged at intervals and symmetrically about the first base 1, and two lower clamping rollers 5 are arranged at intervals and symmetrically about the first base 1. For the upper clamping rollers 2 and lower clamping rollers 5 located on the same side, the lower clamping rollers 5 are located outside the upper clamping rollers 2. This ensures that when the upper clamping rollers 2 and lower clamping rollers 5 are close to each other, the staggered arrangement between the upper clamping rollers 2 and lower clamping rollers 5 can bend the high-performance concrete sample, thereby enabling the testing of the bending resistance of the high-performance concrete.

[0052] In the field of existing concrete sample flexural strength testing, the concrete sample flexural strength testing device has obvious technical limitations when positioning high-performance concrete samples: the current device can only achieve positioning of high-performance concrete samples in the length direction, but lacks a positioning mechanism for the width direction. This lack of positioning mechanism will directly lead to the high-performance concrete sample being misaligned relative to the upper clamping roller 2 in the width direction during the testing process.

[0053] Specifically, when the high-performance concrete sample and the upper clamping roller 2 are misaligned along the width direction, the stress distribution on the high-performance concrete sample will change unevenly due to the positional shift during the bending operation of the upper clamping roller 2 and the lower clamping roller 5. This will have a significant impact on the accuracy of the bending test results, and consequently, the test data will not be able to truly reflect the flexural strength of the high-performance concrete sample.

[0054] Based on this, in the high-performance concrete flexural strength testing system provided in this embodiment of the invention, two bearing seats 11 are also provided on the top of each mounting base 4. The two bearing seats 11 are arranged at intervals along the width direction of the high-performance concrete sample. A bidirectional spiral shaft 6 is simultaneously inserted into the two bearing seats 11 on the same mounting base 4. The bidirectional spiral shaft 6 can rotate around its own axis. The bidirectional spiral shaft 6 and the lower clamping roller 5 are arranged in parallel. A first groove 401 is provided on the top of each mounting base 4. The first groove 401 is a strip structure and extends in a direction parallel to the width of the high-performance concrete sample. The first groove 401 is located between the two bearing seats 11. Each bidirectional spiral shaft 6 has two spiral grooves with opposite directions of rotation. A positioning part 7 is screwed into each spiral groove. The two positioning parts 7 are symmetrically arranged about the first base 1. The positioning part 7 can be set as a block structure, and its bottom is slidably inserted into the first groove 401 during installation. Thus, when the bidirectional spiral shaft 6 rotates in the forward direction, the spiral groove and the positioning part 7 can drive the two positioning parts 7 on the same bidirectional spiral shaft 6 to move closer to each other, thereby moving the high-performance concrete sample in the width direction to align with the upper clamping roller 2 and the lower clamping roller 5. This avoids the impact on the accuracy of the bending test results due to the lack of a positioning mechanism in the width direction when conducting bending tests on the high-performance concrete sample in the future.

[0055] It is understandable that the positioning part 7 can also be configured as a plate, rod, or other forms of structure.

[0056] It should be noted that after the high-performance concrete sample is moved to be aligned with the upper clamping roller 2 and the lower clamping roller 5, the bidirectional spiral shaft 6 needs to be driven to rotate in the opposite direction. Through the spiral engagement between the spiral groove and the positioning part 7, the two positioning parts 7 on the same bidirectional spiral shaft 6 are driven to move away from each other, so that the positioning part 7 and the high-performance concrete sample are no longer in contact, thus avoiding the influence of frictional contact between the positioning part 7 and the high-performance concrete sample on the bending test results.

[0057] In a further embodiment, the existing device also has obvious limitations in its applicability. It can only test concrete samples of standard specifications. When faced with high-performance concrete samples of varying lengths, it cannot achieve adaptive testing through structural adjustments, which to some extent limits its application scenarios in actual engineering testing.

[0058] To effectively solve the above problems, a second slide groove 301 is provided on the top of the second base 3. The second slide groove 301 extends parallel to the length of the high-performance concrete sample. A slider is provided at the bottom of each mounting seat 4. The slider slides into the second slide groove 301 during installation. The high-performance concrete flexural strength testing system also includes a sliding component 8. The sliding component 8 is configured to drive the two mounting seats 4 to slide, ensuring that the two mounting seats 4 can slide synchronously in opposite directions parallel to the length of the high-performance concrete sample. This allows for synchronous adjustment of the distance between the two lower clamping rollers 5, thus adapting to different lengths of high-performance concrete samples. This not only meets the testing requirements of high-performance concrete samples of different lengths but also expands the application range of the system. To prevent the mounting seats 4 from sliding out of the second slide groove 301, blocking blocks 302 are provided on the left and right side walls of the second base 3. The blocking blocks 302 can form a stop with the mounting seats 4.

[0059] Specifically, the sliding component 8 can be configured to include a gear 801 and a rack 802, with a gear 801 sleeved on each bidirectional spiral shaft 6; the rack 802 extends in a direction parallel to the length of the high-performance concrete sample and meshes with the gear 801. Thus, when the bidirectional spiral shaft 6 rotates in the forward direction, on the one hand, through the meshing transmission between the gear 801 and the rack 802, the bidirectional spiral shaft 6, the mounting base 4, and the lower clamping roller 5 can be driven to move towards the center, thereby changing the distance between the two lower clamping rollers 5, and thus adapting to the length of different high-performance concrete samples. This not only meets the testing requirements of high-performance concrete samples of different lengths, but also improves the application range of the system.

[0060] On the other hand, through the spiral engagement between the spiral groove and the positioning part 7, the two positioning parts 7 on the same bidirectional spiral shaft 6 can be driven to move closer to each other, thereby moving the high-performance concrete sample in the width direction to align with the upper clamping roller 2 and the lower clamping roller 5. This avoids the impact on the accuracy of the bending test results due to the lack of a positioning mechanism in the width direction when performing bending tests on the high-performance concrete sample in the future.

[0061] Therefore, by setting the sliding component 8, the distance between the two lower clamping rollers 5 and the distance between the two positioning parts 7 on the same bidirectional spiral shaft 6 can be adjusted simultaneously. This not only makes the operation simple and the adjustment efficiency high, but also helps to improve the detection efficiency.

[0062] The flexural strength testing system for high-performance concrete also includes an adjustment component. This component is configured to, after the two lower clamping rollers 5 have moved into position, move the two positioning parts 7 away from each other without changing the position of the bidirectional spiral shaft 6. Thus, when the bidirectional spiral shaft 6 rotates in the opposite direction, without changing its position, the helical engagement between the spiral groove and the positioning parts 7 moves the two positioning parts 7 on the same bidirectional spiral shaft 6 away from each other, causing the positioning parts 7 to disengage from the high-performance concrete sample and preventing frictional contact between the positioning parts 7 and the high-performance concrete sample from affecting the bending test results.

[0063] Specifically, the adjustment assembly can be configured to include a third base 901, a first elastic element, a wedge-shaped seat 903, a second elastic element, and a mounting base 4. The third base 901 is located below the second base 3 and remains stationary to ensure support for other components. A third elastic element and a top block 9012 are provided on the top of the third base 901. The third elastic element is also connected to the bottom of the second base 3, and the elastic force of the third elastic element is set in the vertical direction to ensure that the second base 3 can slide elastically in the vertical direction and provide power for the reset of the second base 3. The top block 9012 can abut against the bottom of the second base 3 to ensure that it can form a stop with the second base 3, which facilitates support when the high-performance concrete sample is bent. A mounting hole is coaxially and through the end face of gear 801. During installation, gear 801 is fitted onto the double-sided helical shaft 6 through the mounting hole. A first mounting groove 8011 is formed on the inner circumferential wall of the mounting hole, and a second mounting groove is formed on the end circumferential side wall of the double-sided helical shaft 6. The second mounting groove is aligned with the first mounting groove 8011 during installation, and a key 12 is inserted into it. The key 12 is also inserted into the first mounting groove 8011 and is clearance-fitted with the first mounting groove 8011. Initially, the key 12 abuts against the first side wall of the first mounting groove 8011. A first elastic element is connected between each gear 801 and the double-sided helical shaft 6. The elastic force direction of the first elastic element is configured to keep the relative position of gear 801 and double-sided helical shaft 6 in the circumferential direction constant. This ensures that when gear 801 and double-sided helical shaft 6 rotate relative to each other, the first elastic element can simultaneously store force, thereby driving gear 801 or double-sided helical shaft 6 to reset.

[0064] It is understandable that the first elastic element can be set as a torsion spring 902. When installed, the torsion spring 902 is sleeved on the bidirectional spiral shaft 6, and its two ends are respectively connected to the bidirectional spiral shaft 6 and the gear 801. The torsion spring 902 is initially in a relaxed state. When the bidirectional spiral shaft 6 and the gear 801 rotate relative to each other, the torsion spring 902 stores force to provide driving force for the subsequent reverse rotation of the bidirectional spiral shaft 6.

[0065] It is understood that the third elastic element can be configured as the second compression spring 9011 or an elastic rubber body. When the third elastic element is configured as the second compression spring 9011, to ensure that the force of the second compression spring 9011 on the second base 3 is always set in the vertical direction, a guide post 9013 is provided at the top of the third base 901. The guide post 9013 extends in the vertical direction, and its top end is slidably inserted into the second base 3 during installation to ensure that the second base 3 can be guided to slide in the vertical direction. The second compression spring 9011 is sleeved on the guide post 9013 during installation. Under the restriction of the guide post 9013, the second compression spring 9011 can only be compressed or released in the vertical direction. In addition, other elements with elastic energy storage and release functions can also be used in this invention.

[0066] Understandably, in order to improve the stability of the second base 3 when it moves, the number of guide columns 9013 can be set to multiple.

[0067] As an example, the number of guide posts 9013 can be set to four, with the four guide posts 9013 distributed at the four corners of the second base 3.

[0068] The wedge-shaped seat 903 is a strip-shaped cuboid structure that extends along a direction parallel to the length of the high-performance concrete sample, such as... Figure 1 and Figure 2 As shown, taking the wedge-shaped seat 903 located on the front side as an example, a first inclined surface is provided on the rear side wall of the wedge-shaped seat 903, extending in the downward-forward direction; a wedge-shaped strip 9014 is provided on the top of the third base 901. The wedge-shaped strip 9014 is a strip-shaped cuboid structure and extends in a direction parallel to the length of the high-performance concrete sample. Taking the wedge-shaped strip 9014 located on the front side as an example, a second inclined surface is provided on the front side wall of the wedge-shaped strip 9014, extending in the downward-forward direction and forming an inclined surface guide engagement with the first inclined surface. The rack 802 is installed parallel to the top of the wedge-shaped seat 903. Thus, during the downward movement of the wedge-shaped seat 903, through the engagement between the first and second inclined surfaces, the wedge-shaped seat 903 can synchronously drive the rack 802 to move away from the high-performance concrete sample until the gear 801 and the rack 802 disengage, avoiding the influence of the rack 802's support on the gear 801 on the bending test results.

[0069] To facilitate the installation of the wedge seat 903, two mounting plates 9015 are also provided on the top of the third base 901. The two mounting plates 9015 are arranged at intervals along the width direction of the high-performance concrete sample. The plate surfaces of the mounting plates 9015 are vertically arranged. The mounting plates 9015 are strip structures and extend in a direction parallel to the length of the high-performance concrete sample. A third sliding groove 90151 is provided on each mounting plate 9015. The third sliding groove 90151 extends in the vertical direction. A sliding shaft 905 is slidably inserted into the two third sliding grooves 90151. The sliding shaft 905 passes through the left and right side walls of the second base 3 and the wedge seat 903. Under the constraint of the sliding shaft 905, the second base 3 and the wedge seat 903 can slide synchronously in the vertical direction, thereby ensuring the meshing stability between the rack 802 and the gear 801. To facilitate the resetting of the wedge seat 903, a second elastic element is connected between the wedge seat 903 and the third base 901. The elastic force of the second elastic element is configured to cause the wedge seat 903 to tend to move towards the high-performance concrete sample. Thus, as the rack 802 moves away from the high-performance concrete sample, the second elastic element can simultaneously store force, thereby subsequently driving the wedge seat 903 to reset.

[0070] It is understandable that the second elastic element can be set as the first compression spring 904. The first compression spring 904 is sleeved on the sliding shaft 905 and connected between the wedge seat 903 and the mounting plate 9015. When the rack 802 moves away from the high-performance concrete sample, the first compression spring 904 stores force to provide driving force for the subsequent reset of the wedge seat 903.

[0071] Therefore, during use, before the high-performance concrete sample is placed on the two lower clamping rollers 5, the second base 3 and its components will move downward under its own weight, thereby compressing the second compression spring 9011. When the second base 3 and its components are in equilibrium, the second base 3 is in the first position. When the high-performance concrete sample is placed on the two lower clamping rollers 5, the second base 3 and its components, as well as the high-performance concrete sample, will continue to move downward under gravity, further compressing the second compression spring 9011. When the second base 3 and its components, as well as the high-performance concrete sample, are in equilibrium, the second base 3 is in the second position. At this time, the second base 3 and the top block 9012 are spaced apart. During the placement of the high-performance concrete sample, the second base 3 synchronously drives the wedge seat 903 to move downward via the sliding shaft 905. The wedge seat 903 synchronously drives the rack 802 to move downward. At the same time, through the cooperation between the first inclined surface and the second inclined surface, the wedge seat 903 and the rack 802 are synchronously driven to move away from the high-performance concrete sample, and the first compression spring 904 is compressed. When the second base 3 is in the second position, the rack 802 is still in the meshing state with the gear 801.

[0072] Then, the bidirectional spiral shaft 6 is manually rotated in the forward direction. At this time, under the gravity of the high-performance concrete sample, the gear 801 remains stationary through the meshing with the rack 802, and the bidirectional spiral shaft 6 rotates in the direction of loosening the key 12 and the first sidewall, while the torsion spring 902 stores force. During the forward rotation of the bidirectional spiral shaft 6, the key 12 first disengages from the first mounting groove 8011 and then re-engages; when the key 12 abuts against the second sidewall of the first mounting groove 8011, as the bidirectional spiral shaft 6 continues to rotate in the forward direction, the gear 801 is synchronously driven to rotate through the meshing between the key 12 and the first mounting groove 8011, and then the lower clamping roller 5 is moved through the meshing between the gear 801 and the rack 802. Once the clamping roller 5 is in place, the bidirectional spiral shaft 6 is released. At this time, under the gravity of the high-performance concrete sample, the gear 801 remains stationary through meshing with the rack 802, and the torsion spring 902 is released, causing the bidirectional spiral shaft 6 to rotate in the opposite direction. Without changing the position of the bidirectional spiral shaft 6, the spiral groove and the positioning part 7 are engaged to move the two positioning parts 7 on the same bidirectional spiral shaft 6 away from each other, so that the positioning part 7 and the high-performance concrete sample are no longer in contact, thus avoiding the influence of frictional contact between the positioning part 7 and the high-performance concrete sample on the bending test results.

[0073] Then, the first base 1 is moved downwards until the upper clamping roller 2 abuts against the top of the high-performance concrete sample. The first base 1 continues to move downwards, and the upper clamping roller 2 simultaneously pushes the high-performance concrete sample downwards. Simultaneously, the high-performance concrete sample, through the lower clamping roller 5, drives the second base 3 and its components, causing the rack 802 and wedge seat 903 to move downwards. At the same time, through the engagement between the first and second inclined surfaces, the rack 802 and wedge seat 903 move synchronously away from the high-performance concrete sample, and the first compression spring 904 continues to compress. When the second base 3 contacts the top block 9012, the second base 3 is in the third position, and the gear 801 and rack 802 disengage, preventing the rack 802's support of the gear 801 from affecting the bending test results. The first base 1 then continues to move downwards, and the upper clamping roller 2 and lower clamping roller 5 perform bending tests on the high-performance concrete sample.

[0074] When the high-performance concrete sample breaks, the test is completed. The high-performance concrete sample is removed. At this time, under the combined action of the first compression spring 904 and the second compression spring 9011, the high-performance concrete flexural strength testing system is reset, which is convenient for the next test.

[0075] In a further embodiment, to improve the stability of the bidirectional spiral shaft 6 during movement, four gears 801 are provided, with two gears 801 sleeved at both ends of one bidirectional spiral shaft 6 and the other two gears 801 sleeved at both ends of the other bidirectional spiral shaft 6; each gear 801 is connected to the bidirectional spiral shaft 6 through a torsion spring 902 and also forms a gap-type keyway fit with the bidirectional spiral shaft 6; two wedge seats 903 are provided, which are arranged symmetrically and spaced apart along the width direction of the high-performance concrete sample; two wedge strips 9014 are provided, which are arranged spaced apart along the width direction of the high-performance concrete sample and are corresponding to the wedge seats 903; two racks 802 are provided, which are respectively mounted on the two wedge seats 903 and mesh with the two gears 801 located on the same side.

[0076] Specifically, the symmetrical meshing of the four gears 801 with the two racks 802 ensures that the force on both sides of the bidirectional helical shaft 6 is uniform during rotation, eliminating torque deviation caused by unilateral transmission; the symmetrical guiding engagement of the two wedge seats 903 with the two wedge bars 9014 provides dual constraints for the vertical and horizontal movement of the rack 802, ensuring that the rack 802 maintains linear motion during transmission and avoiding gear 801 meshing failure due to offset.

[0077] In other embodiments, to improve the stability of the second base 3 and the wedge seat 903 during movement, two sliding shafts 905 are provided, and the two sliding shafts 905 are arranged at intervals along the length direction of the high-performance concrete sample.

[0078] Specifically in this embodiment, in order to facilitate the installation of the two sliding shafts 905, each mounting plate 9015 is provided with two third sliding grooves 90151, and the two third sliding grooves 90151 on the same mounting plate 9015 are arranged at intervals along the length direction of the high-performance concrete sample.

[0079] During use, the two sliding shafts 905 can simultaneously limit the displacement deviation of the second base 3 and the wedge seat 903 in the length and pitch directions of the high-performance concrete sample. Compared with the guidance of a single sliding shaft 905, its ability to constrain multidimensional displacement is significantly enhanced.

[0080] In other embodiments, to improve the ease of rotating the bidirectional spiral shaft 6, a handwheel 10 is fitted onto each bidirectional spiral shaft 6. Thus, during use, the bidirectional spiral shaft 6 can be rotated via the handwheel 10, thereby reducing the operator's workload.

[0081] In other embodiments, the high-performance concrete flexural strength testing system is further configured to include a hydraulic drive that provides a driving force for sliding the first base 1, ensuring that the upper clamping roller 2 can apply pressure to the top of the high-performance concrete sample from top to bottom, thereby enabling the high-performance concrete sample to be bent by the upper clamping roller 2 and the lower clamping roller 5.

[0082] Specifically, in this embodiment, the hydraulic drive component is a hydraulic cylinder. When installed, the hydraulic cylinder is located above the first base 1. The output shaft of the hydraulic cylinder is set vertically downward and fixed to the top of the first base 1 to ensure that it can drive the first base 1 to slide vertically.

[0083] In other embodiments, the hydraulic cylinder is installed below the third base 901, with its output shaft facing upwards in the vertical direction. Two uprights 101 are threadedly connected to the first base 1 via nuts. The uprights 101 extend vertically and are spaced apart along the width of the high-performance concrete sample, both penetrating the third base 901 during installation. The output shaft of the hydraulic cylinder is also fixedly mounted at the bottom of the two uprights 101, ensuring that the first base 1 can slide vertically via the uprights 101.

[0084] In other embodiments, both upper clamping rollers 2 are rotatably mounted on the mounting base 4 via fixing bolts 13 at the center during installation, and one lower clamping roller 5 is rotatably mounted on the mounting base 4 via fixing bolts 13 at the center during installation, thereby enabling it to adapt to high-performance concrete samples with surface defects.

[0085] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0086] The above-described embodiments are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention.

Claims

1. A flexural testing system for high-performance concrete, characterized in that, The flexural strength testing system for high-performance concrete is configured to perform flexural strength testing on high-performance concrete samples, which are cuboid in shape. The high-performance concrete flexural strength testing system includes a first base that can slide vertically; two upper clamping rollers are provided at the bottom of the first base, the upper clamping rollers being parallel to the width direction of the high-performance concrete sample, the two upper clamping rollers being spaced apart and symmetrically arranged about the first base; a second base is provided below the first base; two mounting seats are provided at the top of the second base, the two mounting seats being spaced apart along the length direction of the high-performance concrete sample; a lower clamping roller is provided at the top of each mounting seat, the lower clamping rollers being parallel to the upper clamping rollers, the two lower clamping rollers being spaced apart and symmetrically arranged about the first base; a bidirectional spiral shaft is also provided at the top of each mounting seat, the bidirectional spiral shaft being parallel to the lower clamping rollers, the bidirectional spiral shaft being rotatable about its own axis, each bidirectional spiral shaft having two spiral grooves with opposite directions of rotation, each spiral groove having a positioning part screwed into it, the two positioning parts being symmetrically arranged about the first base, the positioning parts being configured to position the high-performance concrete sample along the width direction; after positioning the high-performance concrete sample, the positioning parts disengage from the high-performance concrete sample. The two mounting seats are capable of sliding synchronously in opposite directions along a direction parallel to the length of the high-performance concrete sample; the flexural strength testing system for the high-performance concrete also includes a sliding component and an adjusting component, the sliding component being configured to drive the two mounting seats to slide; the adjusting component being configured to drive the two positioning parts away from each other without changing the position of the bidirectional spiral shaft after the two lower clamping rollers have moved into place. The sliding assembly includes a gear and a rack, with the gear sleeved on each of the bidirectional helical shafts; the rack extends along a direction parallel to the length of the high-performance concrete sample and meshes with the gear; The adjusting assembly includes a wedge-shaped seat and a sliding shaft. A third base is disposed below the second base. The second base is disposed on the third base and can slide elastically in the vertical direction, forming a stop engagement with the third base. The gear and the bidirectional spiral shaft are connected by a keyway, and the keyways are clearance-fitted. A first elastic element is connected between each gear and the bidirectional spiral shaft. The elastic force direction of the first elastic element is configured to make the relative position of the gear and the bidirectional spiral shaft in the circumferential direction remain unchanged. The wedge-shaped seat is disposed on the third base and forms an inclined guide engagement with the third base. A second elastic element is connected between the wedge-shaped seat and the third base. The elastic force direction of the second elastic element is configured to make the wedge-shaped seat tend to move towards the high-performance concrete sample. The rack is disposed on the wedge-shaped seat. The sliding shaft is disposed through the second base, the third base, and the wedge-shaped seat, and can slide in the vertical direction. The sliding shaft and the lower clamping roller are arranged parallel to each other.

2. The high-performance concrete flexural strength testing system according to claim 1, characterized in that, The number of gears is set to four, with two gears sleeved at both ends of one of the bidirectional helical shafts and the other two gears sleeved at both ends of the other bidirectional helical shaft; the number of wedge seats is set to two, and the two wedge seats are arranged at intervals along the width direction of the high-performance concrete sample; the number of racks is set to two, and the two racks respectively mesh with the two gears located on the same side.

3. The high-performance concrete flexural strength testing system according to claim 1, characterized in that, There are two sliding shafts, which are arranged at intervals along the length of the high-performance concrete specimen.

4. The high-performance concrete flexural strength testing system according to claim 1, characterized in that, The first elastic element is a torsion spring.

5. The flexural strength testing system for high-performance concrete according to claim 1, characterized in that, The second elastic element is a first compression spring, which is sleeved on the sliding shaft.

6. The flexural strength testing system for high-performance concrete according to claim 1, characterized in that, Each of the bidirectional spiral shafts is fitted with a handwheel.

7. The high-performance concrete flexural strength testing system according to claim 1, characterized in that, The high-performance concrete flexural strength testing system also includes a hydraulic drive configured to provide a driving force for sliding the first base.

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