A bending and torsion testing device for building elements

Abstract

The application discloses a bending and torsion testing device for building components and relates to the field of building component performance testing, which comprises a testing tool mechanism and a load applying mechanism. The testing tool mechanism comprises a rack and two tool assemblies oppositely arranged on the rack. The tool assembly comprises a base slide and a tool mold. The tool mold is rotatably arranged on the base slide. A rectangular mold cavity is arranged along the axial direction of the tool mold. The testing piece is in the shape of a cuboid formed by pouring concrete and reinforcing steel. The two ends of the testing piece are fixedly sleeved with a tensile shaft shoulder and a pressure shaft shoulder. The load applying mechanism comprises a load frame, a load slide and a power assembly. The end face of the load slide close to the testing tool mechanism is provided with the power assembly. The power assembly comprises a pressure testing head. The pressure testing head is used for extruding the testing piece to apply a test load. The defects that the load combination of the existing device is single and the complex working conditions cannot be simulated are solved. The test data has more engineering reference value.

Description

Technical Field

[0001] This invention relates to the field of performance testing of building components, specifically to a bending and torsion testing device for building components. Background Technology

[0002] As the core load-bearing units of a building structure, building components not only bear static loads such as their own weight and live loads during actual service, but also need to resist dynamic loads such as earthquakes, wind, and vibrations. They are often under combined bending, torsion, and axial tension and compression stresses. In particular, the bending and torsional mechanical properties of rectangular components such as concrete beams, columns, and shear walls under complex working conditions directly determine the overall safety and durability of the building structure. Therefore, accurate bending and torsional composite testing is a key part of building engineering design, construction, and quality inspection. As the construction industry develops towards larger spans, higher floors, and greater complexity, the requirements for testing the mechanical performance of building components are becoming increasingly stringent. This necessitates not only simulating single bending and torsional loads but also reproducing complex conditions such as axial prestressing and alternating loads. Simultaneously, it demands the accurate capture of key parameters such as deformation and rotation of components during loading. However, existing bending and torsional testing devices for building components suffer from numerous technical shortcomings, making it difficult to meet the testing needs of actual engineering projects. First, the ability to simulate working conditions is insufficient, and the load combinations are limited. Existing devices are mostly limited to pure bending, pure torsion, or simple bending-torsion combinations, lacking a mechanism for the coordinated application of axial tensile and compressive loads and bending-torsion loads, and thus cannot simulate the "axial prestress + bending-torsion" combined stress state that prestressed concrete members experience in actual service. Secondly, the component fixing and positioning accuracy is low, and the constraint state is distorted. Most building components are cuboid in shape, and existing tooling molds mostly use general-purpose clamping structures, lacking dedicated positioning and locking designs for cuboid components. This makes them prone to slippage and movement during loading, affecting test stability. At the same time, the clamping gap between the mold and the component can easily lead to additional bending moments, further reducing test accuracy.

[0003] Third, deformation monitoring accuracy is low and data integrity is insufficient. Existing devices mostly use single-point displacement sensors for deformation monitoring, which can only measure local deformation of components and cannot fully capture the overall deformation distribution of components under bending and torsional loads. In addition, the position adjustment of the monitoring components is inconvenient and cannot be adapted to the monitoring needs of different components, resulting in the loss of key deformation data and making it difficult to accurately assess the mechanical properties and failure mechanisms of components. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a bending and torsion testing device for building components, thereby addressing the deficiencies of the prior art.

[0005] The objective of this invention is achieved through the following technical solution: a bending and torsion testing device for building components, comprising a testing fixture mechanism and a load application mechanism. The testing fixture mechanism includes a frame and two fixture assemblies mounted opposite each other on the frame. Each fixture assembly includes a base slide and a fixture mold. The fixture mold is rotatably mounted on the base slide, and the base slide is slidably mounted on the frame. The rotation axis of the fixture mold is parallel to the line of movement of the base slide on a horizontal plane. A rectangular cavity is formed through the fixture mold along its own axial direction. The test piece is cast into a cuboid shape using concrete and reinforcing steel. Tensile shoulders are formed at both ends of the test piece. The test piece is fitted with a rectangular mold cavity. Load application mechanisms are provided above, below, and on one side of the test fixture mechanism. Each load application mechanism includes a load frame, a load slide, and a power assembly. The load slide has the freedom to move axially along the tooling mold. A power assembly is located on the end face of the load slide near the test fixture mechanism. The power assembly includes a power base, a pressure test head, and a pressure sensor. The pressure sensor is mounted on the power base. The pressure test head is located on the end face of the power base near the frame, and the pressure test head contacts the pressure shaft of the pressure sensor.

[0006] Furthermore, the top surface of the base slide is provided with an arc-shaped mounting groove, the inner wall of the arc-shaped mounting groove is fixed with an arc-shaped slide rail, the bottom of the tooling mold is provided with an arc-shaped sliding groove, the arc-shaped slide rail is adapted to the arc-shaped sliding groove, and the cross-section of the arc-shaped sliding groove and the cross-section of the arc-shaped slide rail are both T-shaped.

[0007] Furthermore, the base slide has a drive cavity, and a power mechanism is installed in the drive cavity. The power mechanism includes a main shaft and a drive hydraulic rod. The main shaft is rotatably mounted on the base slide through bearings. A drive gear and a drive disk are mounted on the main shaft. The bottom of the tooling mold is fixed with arc-shaped teeth. The arc-shaped mounting groove has a window that communicates with the drive cavity. The drive gear partially passes through the window and meshes with the arc-shaped teeth. The cylinder of the drive hydraulic rod is hinged to the base slide, and the telescopic rod of the drive hydraulic rod is hinged to the drive disk.

[0008] Furthermore, the tooling mold includes an upper mold and a lower mold, with an upper mold cavity and a lower mold cavity respectively provided on the upper mold and the lower mold. The upper mold has a degree of freedom to move in the vertical direction. When the upper mold contacts the lower mold, the upper mold cavity and the lower mold cavity form a rectangular mold cavity.

[0009] Furthermore, a lead screw is rotatably mounted on the top of the lower mold half, and a guide shaft is fixed on the top of the lower mold half. The guide shaft and the lead screw are distributed on both sides of the lower mold cavity. A threaded hole and a guide hole are opened through the upper mold half. The lead screw is threaded to fit the threaded hole, and the guide shaft is slidably fitted to the guide hole. The lower mold half has an inner cavity, and a worm gear is rotatably mounted in the inner cavity. One end of the lead screw passes through the inner cavity and is connected to a worm wheel. The worm wheel meshes with the worm gear, and one end of the worm gear passes out of the lower mold half and is connected to a nut.

[0010] Furthermore, both ends of the test piece are coaxially formed with test shafts, and an encoder is installed on the test shaft. The encoder is installed on the base slide. A tension / compression guide rod is fixed on the frame. The base slide is slidably sleeved on the tension / compression guide rod. Each base slide is equipped with a tension / compression hydraulic rod. The cylinder of the tension / compression hydraulic rod is installed on the frame. The telescopic shaft of the tension / compression hydraulic rod is connected to the base slide.

[0011] Furthermore, the power assembly also includes a load hydraulic rod, the cylinder of which is mounted on a load slide, the telescopic shaft of which is connected to a power base, a telescopic rod is provided between the power base and the pressure test head, the two ends of which are respectively connected to the power base and the pressure test head, and a spring is fitted on the telescopic rod.

[0012] Furthermore, the load application mechanism also includes a linear drive module, which is mounted on the load frame and laid along the moving direction of the base slide. The load slide is mounted on the slide of the linear drive module, and a load-bearing plate is fixedly sleeved on the load slide. The load-bearing plate is connected to the load frame via a screw.

[0013] Furthermore, a deformation monitoring mechanism is provided on the side of the test fixture mechanism away from the load application mechanism. The deformation monitoring mechanism includes a monitoring platform and monitoring components. Several monitoring components are spaced apart on the monitoring platform along the moving direction of the base slide. Each monitoring component includes a monitoring side plate, a monitoring slide shaft, and a distance sensor. The monitoring side plate is slidably mounted on the monitoring platform and has the freedom to move radially along the fixture mold. The monitoring slide shaft slides through the monitoring side plate. A contact ball is fixed at the end of the monitoring slide shaft away from the monitoring side plate. A distance measuring plate is fixedly sleeved on the monitoring slide shaft. A monitoring spring is sleeved on the monitoring slide shaft. The two ends of the monitoring spring are respectively connected to the distance measuring plate and the monitoring side plate. The distance sensor is mounted on the monitoring side plate and is used to monitor the distance position of the distance measuring plate.

[0014] Furthermore, the monitoring platform has a lead screw groove at the position of the corresponding monitoring component, and a monitoring lead screw is rotatably installed in the lead screw groove. A lead screw slider is threaded onto the monitoring lead screw, and the monitoring side plate is fixed on the lead screw slider. One end of the monitoring lead screw passes through the monitoring platform and is connected to an adjusting gear. An intermediate gear is provided between two adjacent adjusting gears. The intermediate gear is rotatably installed on the monitoring platform and meshes with the adjusting gear. One end of one of the monitoring lead screws is connected to a manual turntable.

[0015] The beneficial effects of this invention are: 1. Through the coordinated design of the testing fixture mechanism and the load application mechanism, the coordinated application of multiple loads such as "axial tension and compression + bending + torsion" is realized, which perfectly reproduces the composite stress conditions that prestressed concrete components are subjected to in actual engineering. This solves the defects of existing devices that have a single load combination and cannot simulate complex working conditions, and the test data is more valuable for engineering reference.

[0016] 2. Tensile and compressive shoulders are fabricated on the test piece. When an axial compressive load is applied to the test piece, the tooling mold acts on the compressive shoulder; when an axial tensile load is applied to the test piece, the tooling mold acts on the tensile shoulder. This ensures stable application of axial load to the test piece, preventing shaft movement and radial slippage from affecting test accuracy. Furthermore, the tooling mold has a rectangular cavity that matches the test piece, effectively eliminating clamping gaps and preventing slippage and movement during loading, reducing interference from additional bending moments. The tooling mold can also drive the test piece to twist, applying a stable torsional load to accurately simulate the actual stress constraints of the component in the building structure, thus improving test accuracy.

[0017] 3. The deformation monitoring mechanism is equipped with multiple monitoring components at intervals along the length of the component. Each monitoring component makes elastic contact with the surface of the test piece through a contact ball. The displacement change of the monitoring slide shaft is captured in real time by a distance sensor, so as to realize comprehensive monitoring of the overall deformation distribution of the component. This overcomes the limitation of single-point monitoring of existing devices and provides complete and reliable data support for the analysis of the mechanical properties and failure mechanisms of the component. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of a bending and torsion testing device for building components according to the present invention. Figure 1 ; Figure 2 for Figure 1 Enlarged view of point A in the middle; Figure 3 This is a schematic diagram of the structure of a bending and torsion testing device for building components according to the present invention. Figure 2 ; Figure 4 for Figure 3 Enlarged view at point B in the middle; Figure 5 for Figure 3 Enlarged view at point C; Figure 6 This is a schematic diagram of the structure of a bending and torsion testing device for building components according to the present invention. Figure 3 ; Figure 7 This is a schematic diagram of the assembly of the base slide and the tooling mold in a bending and torsion testing device for building components according to the present invention. Figure 8 This is a schematic diagram of the specimen mold in a bending and torsion testing device for building components according to the present invention. In the diagram, 1-frame, 2-basic slide, 3-tooling mold, 4-rectangular mold cavity, 5-test piece, 6-tension shoulder, 7-pressure shoulder, 8-reinforcing steel bar, 9-load frame, 10-load slide, 11-power seat, 12-pressure test head, 13-pressure sensor, 14-arc mounting groove, 15-arc slide rail, 16-arc slide groove, 17-drive cavity, 18-main shaft, 19-drive hydraulic rod, 20-drive gear, 21-drive disc, 22-arc gear, 23-window, 24-upper mold half, 25-lower mold half, 26-lead screw, 27-guide shaft, 28-threaded hole, 29-guide hole, 30-inner cavity, 31-worm gear, 32-worm wheel, 33-nut, 34-test shaft, 35-... - Encoder, 36- Tension / Compression Guide Rod, 37- Tension / Compression Hydraulic Rod, 38- Load Hydraulic Rod, 39- Telescopic Rod, 40- Spring, 41- Linear Drive Module, 42- Support Plate, 43- Upper Mold, 44- Lower Mold, 45- First Mold Cavity, 46- Second Mold Cavity, 47- Monitoring Platform, 48- Monitoring Side Plate, 49- Monitoring Sliding Shaft, 50- Distance Sensor, 51- Contact Ball, 52- Distance Measuring Plate, 53- Monitoring Spring, 54- Screw Groove, 55- Monitoring Screw, 56- Screw Slider, 57- Adjusting Gear, 58- Intermediate Gear, 59- Manual Turntable, 60- Tension Shaft Shoulder Groove, 61- Pressure Shaft Shoulder Groove, 62- Rebar Hole, 63- Upper Semicircular Groove, 64- Lower Semicircular Groove, 65- Grouting Hole, 66- Screw. Detailed Implementation

[0019] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings, but the scope of protection of the present invention is not limited to the following description.

[0020] Example 1 like Figures 1 to 8As shown, a bending and torsion testing device for building components includes a testing fixture mechanism and a load application mechanism. The testing fixture mechanism includes a frame 1 and two fixture assemblies mounted opposite each other on the frame 1. Each fixture assembly includes a base slide 2 and a fixture mold 3. The fixture mold 3 is rotatably mounted on the base slide 2, and the base slide 2 is slidably mounted on the frame 1. The rotation axis of the fixture mold 3 is parallel to the line of movement of the base slide 2 on a horizontal plane. A rectangular cavity 4 is formed through the fixture mold 3 along its own axial direction. The test piece 5 is cast into a cuboid shape by concrete and steel reinforcement. Both ends of the test piece 5 have tensile shoulders 6 and compressive shoulders 7. Reinforcing steel bars 8 are embedded in both the tensile shoulders 6 and the compressive shoulders 7. The test piece 5 is matched with the rectangular cavity 4. Load application mechanisms are provided above, below, and on one side of the test fixture mechanism. These mechanisms include a load frame 9, a load slide 10, and a power assembly. The load slide 10 has the freedom to move axially along the fixture mold 3. A power assembly is located near the end face of the load slide 10 close to the test fixture mechanism. The power assembly includes a power base 11, a pressure test head 12, and a pressure sensor 13. The pressure sensor 13 is mounted on the power base 11. The pressure test head 12 is located near the end face of the power base 11 close to the frame 1. The pressure test head 12 contacts the pressure axis of the pressure sensor 13. Standard-sized building components, i.e., test pieces 5, need to be fabricated for testing. Test pieces 5 are fabricated using a test piece mold, ensuring that both ends of the test piece 5 have tensile shoulders 6 and pressure... The tensile shoulder 6 and compressive shoulder 7 at one end of the test piece 5 form a tooling area. The tooling areas at both ends of the test piece 5 are respectively fitted into the rectangular cavities 4 of the two tooling molds 3. After the test piece 5 is tooled, performance testing is performed. The two basic slides 2 move closer to the middle of the test piece 5. At this time, the compressive shoulder 7 abuts against the tooling mold 3, thereby applying pressure from both ends of the test piece 5 through the two basic slides 2 to simulate the bearing state of building components such as columns and walls. Then, pressure is applied to the side of the test piece 5 through the load application mechanism to obtain the bending performance of the test piece 5 under compression. This is used to explore the bending resistance of building components under compression. By changing the pressure at both ends of the test piece 5, the bending resistance under different compressions can be studied. The influence of the base slide 2 moving away from the center of the test piece 5, at which time the tension shoulder 6 abuts against the tooling mold 3, so that the two base slides 2 apply tension to both ends of the test piece 5 respectively, simulating the tension state of building components such as beams and plates. The load application mechanism applies pressure to the side of the test piece 5 to obtain the bending performance of the test piece 5 under tension, which is used to explore the bending resistance of building components under tension. By adjusting the tension at both ends of the test piece 5, the influence of different tension conditions on the bending resistance is studied. Thus, by setting the tension shoulder 6 and the pressure shoulder 7, the base slide 2 can accurately apply tension or pressure to the test piece 5 to simulate the actual stress state of building components, thereby accurately obtaining the physical properties of building components.Secondly, the tooling mold 3 can rotate on the base slide 2. When the actual building component is subjected to complex forces, i.e., when the building component is also affected by torsion, the tooling mold 3 deflects on the base slide 2. Since the cross-section of the rectangular mold cavity 4 and the cross-section of the test piece 5 are both rectangular, there is no relative rotational freedom between the rectangular mold cavity 4 and the test piece 5. This allows the tooling mold 3 to apply torsion to the test piece 5, which can simulate the axial tension or axial compression + torsion combined stress state of the building component. This can test the bending and torsional performance of the building component, making the test data more accurate. Load application mechanisms are set above, below, and on one side of the test tooling mechanism, which can also simulate the lateral force of the building component. The load slide 10 can move along the length of the test piece 5, so that the pressure test head 12 can act on the test piece 5. Pressure is applied to different regions along the length of test piece 5. During testing, only one load application mechanism is activated to apply pressure, studying the effect of single lateral pressure on the bending and torsional properties of test piece 5. The position of the pressure test head 12 can also be adjusted to study the bending and torsional properties of building components under different pressure positions. Activating two or three load application mechanisms allows for the study of the environmental state of multiple pressure positions on the side of the building component, obtaining the bending and torsional properties under combined stress. The aforementioned compression, tension, torsion, and lateral pressure can be arbitrarily combined to simulate the complex stress state of building components, overcoming the shortcomings of existing devices that have a single load combination and cannot simulate complex working conditions. The test data has greater engineering reference value. In specific implementation, a vision inspection system can be arranged on the side of the test fixture away from the load application mechanism. The vision inspection system includes a vision mounting frame with multiple industrial cameras arranged along the axial direction of the fixture mold 3. The industrial cameras capture the testing process of test piece 5 for analysis of the deformation of test piece 5.

[0021] Example 2 Based on Example 1, such as Figure 1 , Figure 2 and Figure 8As shown, the specimen mold includes an upper mold 43 and a lower mold 44. The top of the upper mold 43 has a first mold cavity 45, and the bottom of the lower mold 44 has a second mold cavity 46. The first mold cavity 45 and the second mold cavity 46 are closed to form the forming mold cavity of the test specimen 5. The upper mold 43 has a tension shaft shoulder groove 60 on the top wall of the first mold cavity 45, and the lower mold 44 has a pressure shaft shoulder groove 61 on the bottom wall of the second mold cavity 46. The tension shaft shoulder groove 60 and the pressure shaft shoulder groove 61 of the lower mold 44 are both provided with steel bar holes 62. The bottom surface of the upper mold 43 has upper semi-circular grooves 63 at both ends, and the top surface of the lower mold has lower semi-circular grooves 64 at both ends. The lower semi-circular grooves 64 and the upper semi-circular grooves 63 are combined to form the forming mold cavity of the test shaft 34. The top surface of the upper mold 43 has a grouting hole 65 that connects to the first mold cavity 45. The reinforcing cage is placed into the second cavity 46 of the lower mold 44, and then reinforcing steel bars 8 are inserted into the reinforcing bar holes 62 to enhance the strength of the tensile shoulder 6 and the compressive shoulder 7, so that the tensile shoulder 6 and the compressive shoulder 7 will not be damaged when the force is transmitted to the test piece 5. Then the upper mold 43 and the lower mold 44 are closed, and concrete is poured into the forming mold cavity through the grouting hole 65. After the concrete cools, the upper mold 43 is removed to obtain the test piece 5, and the tensile shoulder 6, the compressive shoulder 7 and the test shaft 34 are formed on the test piece 5. By placing different reinforcing cages and pouring concrete with different formulas, different building components can be made. Building components with different proportions and different amounts of reinforcing bars can be made into uniform size and shape through the test piece mold, which can reduce variables and study the physical properties of different building components.

[0022] Example 3 Based on Example 2, such as Figures 1 to 6As shown, a deformation monitoring mechanism is provided on the side of the test fixture away from the load application mechanism. The deformation monitoring mechanism includes a monitoring platform 47 and monitoring components. Several monitoring components are spaced apart on the monitoring platform 47 along the moving direction of the base slide 2. The monitoring components include a monitoring side plate 48, a monitoring slide shaft 49, and a distance sensor 50. The monitoring side plate 48 is slidably mounted on the monitoring platform 47 and has the freedom to move radially along the fixture mold 3. The monitoring slide shaft 49 is slidably mounted on the monitoring side plate 48. A contact ball 51 is fixed to the end of the monitoring slide shaft 49 away from the monitoring side plate 48. A distance measuring plate 52 is fixedly sleeved on the monitoring slide shaft 49, and a monitoring spring 53 is sleeved on the monitoring slide shaft 49. The two ends of the monitoring spring 53 are respectively connected to the distance measuring plate 52 and the monitoring side plate 48. Distance sensor 50 is installed on monitoring side plate 48 to monitor the distance position of distance measuring plate 52. The deformation monitoring mechanism can accurately obtain the deformation of test piece 5 at different positions. Specifically, before the test, the position of the monitoring components is adjusted so that the contact ball 51 in each monitoring component contacts the building component. Then the test is carried out. When the test piece 5 deforms during the test, the test piece 5 will push the monitoring slide shaft 49 to squeeze the monitoring spring 53 through the contact ball 51, causing the position of distance measuring plate 52 to change. The displacement value of distance measuring plate 52 is monitored by distance sensor 50, thereby accurately reflecting the deformation value of test piece 5. By combining multiple sets of monitoring components, the degree of deformation of test piece 5 at different positions can be obtained, thus making the data monitoring value of test piece 5 more comprehensive.

[0023] Example 4 Based on Example 3, such as Figures 1 to 3 As shown, the monitoring platform 47 has a lead screw groove 54 at the position of the corresponding monitoring component. A monitoring lead screw 55 is rotatably mounted in the lead screw groove 54. A lead screw slider 56 is threaded onto the monitoring lead screw 55. The monitoring side plate 48 is fixed to the lead screw slider 56. One end of the monitoring lead screw 55 passes through the monitoring platform 47 and is connected to an adjusting gear 57. An intermediate gear 58 is provided between two adjacent adjusting gears 57. The intermediate gear 58 is rotatably mounted on the monitoring platform 47 and meshes with the adjusting gear 57. One end of one of the monitoring lead screws 55 is connected to a manual turntable 59. Rotating the manual turntable 59 drives the monitoring lead screw 55 to rotate. The meshing of the intermediate gear 58 and the adjusting gear 57 drives all the monitoring lead screws 55 to rotate, causing the lead screw slider 56 to move the monitoring side plate 48 closer to the test piece 5, so that the contact ball 51 contacts the test piece 5. Under the action of the monitoring spring 53, it can adapt to the manufacturing error of the test piece 5. When the contact ball 51 in some monitoring components contacts the test piece 5 first, the monitoring spring 53 is compressed, causing the monitoring sliding shaft 49 to slide, avoiding interference with the test piece 5. After all the contact balls 51 in all monitoring components have contacted the test piece 5, the manual turntable 59 is stopped, so that the position adjustment of all monitoring components can be completed at one time. The operation is simple and quick.

[0024] Example 5 Based on Example 4, such as Figures 1 to 6 As shown, test shafts 34 are coaxially formed at both ends of test piece 5. Encoders 35 are mounted on the test shafts 34 and are installed on the base slide 2. A tension / compression guide rod 36 is fixed on the frame 1. The base slide 2 is slidably fitted onto the tension / compression guide rod 36. Each base slide 2 is equipped with a tension / compression hydraulic rod 37. The cylinder of the tension / compression hydraulic rod 37 is mounted on the frame 1, and the telescopic shaft of the tension / compression hydraulic rod 37 is connected to the base slide 2. The housing of the encoder 35 is mounted on the test frame, which is then screwed onto the frame 1. The encoder 35 monitors... The torsional state of test piece 5 is monitored by encoder 35 when the tooling mold 3 applies torque to test piece 5. When test piece 5 undergoes torsional deformation, test shaft 34 on test piece 5 will deflect to a certain extent. By identifying the deflection of test shaft 34 through encoder 35, the torsional resistance of test piece 5 can be obtained quickly and accurately. The base slide 2 is moved along the length direction of test piece 5 by tension hydraulic rod 37, and tension is applied to test piece 5 in conjunction with tension shoulder 6 and pressure is applied to test piece 5 in conjunction with pressure shoulder 7.

[0025] Example 5 Based on Example 4, such as Figures 1 to 7 As shown, the power assembly also includes a load hydraulic rod 38. The cylinder of the load hydraulic rod 38 is mounted on the load slide 10. The telescopic shaft of the load hydraulic rod 38 is connected to the power seat 11. A telescopic rod 39 is provided between the power seat 11 and the pressure test head 12. The two ends of the telescopic rod 39 are respectively connected to the power seat 11 and the pressure test head 12. A spring 40 is fitted on the telescopic rod 39. The power assembly applies pressure to the side of the test piece 5 to test the bending resistance of the test piece 5. Specifically, the load hydraulic rod 38 drives the power seat 11 to move closer to the test piece 5, so that the pressure test head 12 contacts the test piece 5. The load hydraulic rod 38 gradually increases the pressure on the test piece 5 through the pressure test head 12. The pressure reaction between the pressure test head 12 and the test piece 5 is applied to the pressure sensor 13, thereby making the pressure applied by the pressure test head 12 to the test piece 5 visible. The deformation state of the test piece 5 is then monitored in real time by the deformation monitoring mechanism to obtain the bending resistance parameters of the test piece 5.

[0026] Furthermore, the load application mechanism also includes a linear drive module 41, which is mounted on the load frame 9 and laid along the moving direction of the base slide 2. The load slide 10 is mounted on the slide of the linear drive module 41, and a load bearing plate 42 is fixedly sleeved on the load slide 10. The load bearing plate 42 is connected to the load frame 9 through a screw 66. The linear drive module 41 drives the load slide 10 to move, adjusting the relative position between the pressure test head 12 and the test piece 5. Pressure can be applied at different positions along the length of the test piece 5. Several pressure-bearing threaded holes are opened on the load frame 9 along the length of the test piece 5. After the position of the load slide 10 is adjusted, the screw 66 is screwed into the corresponding pressure-bearing threaded hole, thereby connecting the load slide 10 to the load frame 9. The reaction force between the pressure test head 12 and the test piece 5 is mainly borne by the screw 66, avoiding the reaction pressure acting on the slide of the linear drive module 41, thus protecting the linear drive module 41.

[0027] Example 6 Based on Example 5, such as Figures 1 to 7 As shown, the top surface of the base slide 2 is provided with an arc-shaped mounting groove 14, and an arc-shaped slide rail 15 is fixed to the inner wall of the arc-shaped mounting groove 14. The bottom of the tooling mold 3 is provided with an arc-shaped sliding groove 16, and the arc-shaped slide rail 15 is adapted to the arc-shaped sliding groove 16. The cross-section of the arc-shaped sliding groove 16 and the cross-section of the arc-shaped slide rail 15 are both T-shaped, so that the tooling mold 3 can slide along the center of the arc-shaped slide rail 15 on the base slide 2. The arc-shaped slide rail 15 and the tooling mold 3 are concentrically arranged, so that the tooling mold 3 can deflect around its own axis, thereby applying torque to the test piece 5. The base slide 2 is provided with a drive cavity 17, and a power mechanism is provided in the drive cavity 17. The power mechanism includes a main shaft 18 and a drive hydraulic rod 19. The main shaft 18 is rotatably mounted on the base slide 2 through bearings. The tooling mold 3 is equipped with a drive gear 20 and a drive disk 21. The bottom of the tooling mold 3 is fixed with an arc-shaped tooth 22. The arc-shaped mounting groove 14 has a window 23 that connects to the drive cavity 17. The drive gear 20 partially passes through the window 23 and meshes with the arc-shaped tooth 22. The cylinder of the drive hydraulic rod 19 is hinged to the base slide 2, and the telescopic rod of the drive hydraulic rod 19 is hinged to the drive disk 21. When it is necessary to apply torque to the test piece 5, the drive hydraulic rod 19 applies torque to the main shaft 18 through the drive disk 21. The main shaft 18 applies torque to the tooling mold 3 through the meshing of the drive gear 20 and the arc-shaped tooth 22. The tooling mold 3 then applies torque to the test piece 5. The drive hydraulic rod 19 gradually increases the hydraulic pressure to increase the torque on the test piece 5 in order to study the torsional resistance of the test piece 5.

[0028] Example 7 Based on Example 6, such as Figures 1 to 7As shown, the tooling mold 3 includes an upper mold 24 and a lower mold 25. The upper mold 24 and lower mold 25 are respectively provided with an upper mold cavity and a lower mold cavity. The upper mold 24 has a degree of freedom to move vertically. When the upper mold 24 contacts the lower mold 25, the upper and lower mold cavities form a rectangular mold cavity 4. A lead screw 26 is rotatably mounted on the top of the lower mold 25, and a guide shaft 27 is fixed to the top of the lower mold 25. The guide shaft 27 and the lead screw 26 are distributed on both sides of the lower mold cavity. A threaded hole 28 and a guide hole 29 are provided through the upper mold 24. The lead screw 26 is threaded into the threaded hole 28, and the guide shaft 27 is slidably adapted to the guide hole 29. The lower mold 25 has an inner cavity 30, and a worm gear 31 is rotatably mounted inside the inner cavity 30. One end of the lead screw 26 passes through the inner cavity 30 and is connected to a worm wheel 32. The worm wheel 32 meshes with the worm gear 31. One end of rod 31 extends out of the lower half mold 25 and is connected to nut 33. Using a wrench to turn nut 33, nut 33 drives worm wheel 32 to rotate via worm 31. Worm wheel 32 drives lead screw 26 to rotate. The rotational freedom of upper half mold 24 is restricted by the cooperation of guide shaft 27 and guide hole 29, so that upper half mold 24 can move linearly along the axis of lead screw 26. By rotating worm 31 in the forward or reverse direction, upper half mold 24 can move up or down. When tooling test piece 5, moving upper half mold 24 upward increases the distance between upper half mold 24 and lower half mold 25, so that the end of test piece 5 can pass smoothly through rectangular mold cavity 4. The area between tensile shoulder 6 and pressure shoulder 7 of test piece 5 is located in rectangular mold cavity 4. Then upper half mold 24 is reset downward, so that test piece 5 is fitted into rectangular mold cavity 4, completing the tooling of test piece 5. In practice, both the tension shoulder 6 and the pressure shoulder 7 protrude from the top and bottom surfaces of the test piece 5. The two sides of the tension shoulder 6 are flush with the two sides of the test piece 5, and the two sides of the pressure shoulder 7 are flush with the two sides of the test piece 5, so that the end of the test piece 5 can pass smoothly between the upper half mold 24 and the lower half mold 25, thus achieving smooth tooling of the test piece 5.

Claims

1. A bending and torsion testing device for building components, characterized in that, The test fixture includes a testing tooling mechanism and a load application mechanism. The testing tooling mechanism comprises a frame and two tooling assemblies mounted opposite each other on the frame. Each tooling assembly includes a base slide and a tooling mold. The tooling mold is rotatably mounted on the base slide, and the base slide is slidably mounted on the frame. The rotation axis of the tooling mold is parallel to the linear motion of the base slide on a horizontal plane. A rectangular cavity is formed through the tooling mold along its axial direction. The test piece is cast into a cuboid shape using concrete and reinforcing steel. Tensile and compressive shoulders are formed at both ends of the test piece. The tensile shoulder is connected to the compressive shoulder... All are internally reinforced with steel bars. The test piece matches a rectangular mold cavity. Load application mechanisms are provided above, below and on one side of the test fixture mechanism. The load application mechanism includes a load frame, a load slide and a power assembly. The load slide has the freedom to move along the axial direction of the fixture mold. The power assembly is provided on the end face of the load slide near the test fixture mechanism. The power assembly includes a power base, a pressure test head and a pressure sensor. The pressure sensor is mounted on the power base. The pressure test head is provided on the end face of the power base near the frame. The pressure test head contacts the pressure shaft of the pressure sensor.

2. The bending and torsion testing device for building components according to claim 1, characterized in that, The top surface of the base slide is provided with an arc-shaped mounting groove, and an arc-shaped slide rail is fixed to the inner wall of the arc-shaped mounting groove. The bottom of the tooling mold is provided with an arc-shaped sliding groove, and the arc-shaped slide rail is adapted to the arc-shaped sliding groove. The cross-section of the arc-shaped sliding groove and the cross-section of the arc-shaped slide rail are both T-shaped.

3. The bending and torsion testing device for building components according to claim 2, characterized in that, The base slide has a drive cavity, and a power mechanism is installed in the drive cavity. The power mechanism includes a main shaft and a drive hydraulic rod. The main shaft is rotatably mounted on the base slide through bearings. A drive gear and a drive disk are mounted on the main shaft. The bottom of the tooling mold is fixed with arc-shaped teeth. The arc-shaped mounting groove has a window that connects to the drive cavity. The drive gear partially passes through the window and meshes with the arc-shaped teeth. The cylinder of the drive hydraulic rod is hinged to the base slide, and the telescopic rod of the drive hydraulic rod is hinged to the drive disk.

4. The bending and torsion testing device for building components according to claim 1, characterized in that, The tooling mold includes an upper mold and a lower mold. The upper mold and the lower mold are respectively provided with an upper mold cavity and a lower mold cavity. The upper mold has the freedom to move in the vertical direction. When the upper mold contacts the lower mold, the upper mold cavity and the lower mold cavity form a rectangular mold cavity.

5. A bending and torsion testing device for building components according to claim 4, characterized in that, A lead screw is rotatably mounted on the top of the lower mold half, and a guide shaft is fixed on the top of the lower mold half. The guide shaft and the lead screw are distributed on both sides of the lower mold cavity. A threaded hole and a guide hole are opened through the upper mold half. The lead screw is threaded to fit the threaded hole, and the guide shaft is slidably fitted to the guide hole. The lower mold half has an inner cavity, and a worm gear is rotatably mounted in the inner cavity. One end of the lead screw passes through the inner cavity and is connected to a worm wheel. The worm wheel meshes with the worm gear, and one end of the worm gear passes through the lower mold half and is connected to a nut.

6. A bending and torsion testing device for building components according to claim 1, characterized in that, Both ends of the test piece are coaxially formed with test shafts, and an encoder is installed on the test shaft. The encoder is installed on the base slide. A tension and compression guide rod is fixed on the frame. The base slide is slidably sleeved on the tension and compression guide rod. Each base slide is equipped with a tension and compression hydraulic rod. The cylinder of the tension and compression hydraulic rod is installed on the frame. The telescopic shaft of the tension and compression hydraulic rod is connected to the base slide.

7. A bending and torsion testing device for building components according to claim 1, characterized in that, The power assembly also includes a load hydraulic rod, the cylinder of which is mounted on a load slide, the telescopic shaft of which is connected to a power base, and a telescopic rod is provided between the power base and the pressure test head. The two ends of the telescopic rod are respectively connected to the power base and the pressure test head, and a spring is fitted on the telescopic rod.

8. A bending and torsion testing device for building components according to claim 7, characterized in that, The load application mechanism further includes a linear drive module, which is installed on the load frame and laid along the moving direction of the base slide. The load slide is installed on the slide of the linear drive module, and a load-bearing plate is fixedly sleeved on the load slide. The load-bearing plate is connected to the load frame through a screw.

9. A bending and torsion testing device for building components according to claim 1, characterized in that, A deformation monitoring mechanism is provided on the side of the test fixture away from the load application mechanism. The deformation monitoring mechanism includes a monitoring platform and monitoring components. Several monitoring components are spaced apart on the monitoring platform along the moving direction of the base slide. Each monitoring component includes a monitoring side plate, a monitoring slide shaft, and a distance sensor. The monitoring side plate is slidably mounted on the monitoring platform and has a degree of freedom to move radially along the fixture mold. The monitoring slide shaft slides through the monitoring side plate. A contact ball is fixed at the end of the monitoring slide shaft away from the monitoring side plate. A distance measuring plate is fixedly sleeved on the monitoring slide shaft. A monitoring spring is sleeved on the monitoring slide shaft. The two ends of the monitoring spring are respectively connected to the distance measuring plate and the monitoring side plate. The distance sensor is mounted on the monitoring side plate and is used to monitor the distance position of the distance measuring plate.

10. A bending and torsion testing device for building components according to claim 9, characterized in that, The monitoring platform has a lead screw groove at the position of the corresponding monitoring component. A monitoring lead screw is rotatably installed in the lead screw groove. A lead screw slider is threaded onto the monitoring lead screw. The monitoring side plate is fixed on the lead screw slider. One end of the monitoring lead screw passes through the monitoring platform and is connected to an adjusting gear. An intermediate gear is provided between two adjacent adjusting gears. The intermediate gear is rotatably installed on the monitoring platform and meshes with the adjusting gear. One end of one of the monitoring lead screws is connected to a manual turntable.

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