Ultra high performance concrete restrained shrinkage test device

Abstract

The application relates to the technical field of ultra-high performance concrete restrained shrinkage testing, in particular to an ultra-high performance concrete restrained shrinkage testing device, which comprises a rack and a testing mechanism; the testing mechanism comprises a clamp one, a clamp two, a tension sensor, a plurality of strain gauges, a bottom plate one, a bottom plate two and a bottom plate three; a mold mechanism comprises an upper mold plate, a lower mold plate, a plurality of side mold plates and a mold assembling component; the lower mold plate comprises a middle plate, an end plate one and an end plate two; the end plate one and the end plate two are movably inserted on the two sides of the middle plate; a plate changing mechanism comprises a sliding plate and a plate changing component; a lifting mechanism comprises a plurality of lifting components, and the plurality of lifting components are arranged on the two sides of the testing mechanism respectively; the testing mechanism, the mold mechanism, the plate changing mechanism and the lifting mechanism are connected with a controller respectively; the testing device provided by the application realizes the integration of the preparation and the testing process of the concrete test piece based on the principle of end restraint.

Description

Technical Field

[0001] This invention relates to the field of confined shrinkage testing technology for ultra-high performance concrete, specifically to a confined shrinkage testing device for ultra-high performance concrete. Background Technology

[0002] Ultra-high performance concrete, or UHPC for short, also known as reactive powder concrete, has mechanical properties close to those of steel structures when properly reinforced, while also possessing excellent wear resistance and blast resistance. Therefore, due to the rapid development of concrete materials and construction technology, large-volume continuous casting technology is increasingly being applied in practical engineering, and the use of ultra-high performance concrete in engineering projects is also constantly increasing. Deformation cracks (especially in the early stages) are becoming increasingly serious. The formation of early cracks is generally not caused by structural loads or construction loads, but is mostly attributed to excessive tensile stress generated by the constraint of concrete deformation. Constraints can be mostly divided into internal constraints and external constraints. External constraints are the constraints on the deformation of concrete components (temperature shrinkage, autogenous shrinkage, drying shrinkage, etc.) by adjacent concrete components or the foundation.

[0003] External constraints can be divided into two types: end constraints, such as beams and frames, where the deformation of concrete members is constrained by adjacent members; and continuous constraints, such as slabs and foundations. Common examples of continuous constraints include concrete pavement slabs poured on the base layer and walls poured on the foundation. Axial constraint shrinkage testing is currently an ideal method for evaluating the early constraint shrinkage of concrete. Therefore, I propose an end constraint-based ultra-high concrete constraint shrinkage testing device. Summary of the Invention

[0004] The purpose of this invention is to provide a test device for the confined shrinkage of ultra-high performance concrete to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: an ultra-high performance concrete confined shrinkage testing device, comprising a frame, and further comprising:

[0006] The testing mechanism is used for constrained shrinkage testing of ultra-high concrete specimens. The shrinkage testing mechanism is located in the middle of the frame.

[0007] A mold mechanism, in conjunction with a testing mechanism, is used for casting and molding specimens. The mold mechanism includes an upper mold plate, a lower mold plate, multiple side mold plates, and a mold assembly. The lower mold plate includes a middle plate, an end plate one, and an end plate two, which are movably inserted into both sides of the middle plate.

[0008] A plate changing mechanism, used in conjunction with a testing mechanism, includes a sliding plate and a plate changing assembly;

[0009] A lifting mechanism for lifting a test specimen, the lifting mechanism comprising multiple lifting components, the multiple lifting components being respectively disposed on both sides of the testing mechanism;

[0010] The controller is connected to the testing mechanism, mold mechanism, plate changing mechanism and lifting mechanism respectively.

[0011] The testing mechanism, mold mechanism, plate changing mechanism, lifting mechanism, and controller are respectively connected to the frame.

[0012] Preferably, the testing mechanism includes a first fixture, a second fixture, a tensile sensor, several strain gauges, a first base plate, a second base plate, and a third base plate;

[0013] The clamp includes a clamping plate, a clamping plate, and a connecting plate. The bottom of the clamping plate is connected to the surface of the base plate. The connecting plate is disposed between the clamping plate and the clamping plate. One end of the connecting plate is connected to the surface of the clamping plate. A plurality of studs are connected to the end of the connecting plate away from the fixing plate. The studs penetrate the clamping plate. Both ends of the base plate are connected to the frame.

[0014] The clamp 2 includes a clamping plate 3, a clamping plate 4, and a connecting plate 2. The connecting plate 2 is disposed between the clamping plate 3 and the clamping plate 4. One end of the connecting plate 2 is connected to the surface of the clamping plate 3. The end of the connecting plate 2 away from the clamping plate 3 is connected to a plurality of studs 2, which penetrate the clamping plate 4. A plurality of sliding grooves are opened on one side of the clamping plate 4, and sliding blocks are slidably disposed in the sliding grooves. One end of the tension sensor is connected to the connecting plate 2, and the end of the tension sensor away from the connecting plate 2 is connected to the frame. The base plate 2 is disposed at the lower part of the clamping plate 3, and the base plate 3 is disposed at the lower part of the clamping plate 4. One end of the base plate 2 and the base plate 3 are respectively connected to the frame.

[0015] Multiple strain gauges are respectively disposed on the inner surfaces of clamping plates one, two, three and four; the strain gauges and the tension sensor are respectively connected to an external data acquisition device.

[0016] Preferably, one end of the clamping plate 1, clamping plate 2, clamping plate 3 and clamping plate 4 is provided with an insert block, and the two ends of the side template are respectively provided with slots that cooperate with the insert blocks.

[0017] Preferably, the testing mechanism further includes a clamping electric cylinder one, a clamping electric cylinder two, a connecting seat one and a connecting seat two, the lower part of the clamping electric cylinder one is connected to the base plate one, one end of the clamping electric cylinder one is hinged to the connecting seat one, and one end of the connecting seat one is connected to the clamping plate two;

[0018] The lower part of the clamping electric cylinder 2 is connected to the base plate 3, one end of the connecting seat 2 is connected to the sliding block, and the end of the connecting seat 2 away from the clamping plate 4 is connected to the clamping electric cylinder 2; the clamping electric cylinder 1 and the clamping electric cylinder 2 are respectively connected to the controller.

[0019] Preferably, the module assembly includes a mounting plate, electric cylinder one, electric cylinder two, electric cylinder three, electric cylinder four, a distance sensor, and multiple guide slides. Both ends of the mounting plate are connected to the frame. Electric cylinder one is positioned on the upper part of the mounting plate, with its lower part penetrating the mounting plate and connecting to the upper template. Electric cylinder two and electric cylinder three are positioned on one side of electric cylinder one, with their lower parts penetrating the mounting plate and connecting to their respective side templates. The lower parts of the multiple guide slides penetrate the mounting plate and connect to their respective side templates, with anti-detachment plates provided on the upper parts of each guide slide. The upper part of electric cylinder four is connected to the lower template, and its lower part is connected to the frame. The distance sensor is positioned on one side of electric cylinder four, and the distance sensor, electric cylinder one, electric cylinder two, electric cylinder three, and electric cylinder four are all connected to a controller.

[0020] Preferably, the plate changing assembly includes a push cylinder, a frame, a support plate, multiple support frames, and a sliding plate for reducing the frictional resistance of the specimen. The frame is connected to the machine frame, the support plate is disposed inside the frame, and both ends of the support plate are respectively connected to the support frames and the frame. The sliding plate is slidably disposed on the upper surface of the support plate. The sliding plate is made of polytetrafluoroethylene (PTFE). An adsorption iron block is provided on one side of the sliding plate. One end of the push cylinder is connected to the support plate, and an electromagnet is provided at one end of the push cylinder. The electromagnet is connected to a controller.

[0021] Preferably, the lifting assembly includes a first propulsion cylinder, a second propulsion cylinder, a first propulsion plate, a second propulsion plate, a first support plate, and a second support plate. The first support plate is located on the side of the first propulsion plate away from the first propulsion cylinder, and the first support plate is hinged to the first propulsion plate. The second support plate is located on the side of the second propulsion plate away from the second propulsion cylinder, and the second support plate is hinged to the second propulsion plate. The first propulsion cylinder is disposed on one side of the first connecting plate, and one end of the first propulsion cylinder is connected to the first propulsion plate. A mounting platform is provided at the lower part of the first propulsion cylinder, and the lower part of the mounting platform is connected to the first base plate. The first support plate is located at the upper part of the first connecting plate.

[0022] The second propulsion cylinder is located on one side of the second connecting plate. The lower part of the second propulsion cylinder is connected to the frame. The second propulsion plate is connected to one end of the second propulsion cylinder. The lower part of the second propulsion plate has a through groove that cooperates with the tension sensor. The second support plate is located on the upper part of the second connecting plate. The first propulsion cylinder and the second propulsion cylinder are respectively connected to the controller.

[0023] Compared with the prior art, the beneficial effects of the present invention are:

[0024] 1. In this invention, the upper template, lower template, and two side templates in the mold mechanism are combined with clamp one and clamp two to form a mold for casting specimens. The structure of this mold is wide at both ends and narrow in the middle. The high-performance concrete specimens produced also have a structure that is wide at both ends and narrow in the middle, which makes it easy to clamp them in the end constraint test by clamp one and clamp two. Clamp one and clamp two can not only serve as fixed ends and movable ends to clamp the two ends of the high-performance concrete specimen to be tested, but also serve as part of the specimen mold making process, eliminating the need to make a separate mold.

[0025] 2. In this invention, strain gauges have been installed on the inner surfaces of clamping plates one, two, three and four to measure the force exerted by the end of the specimen on clamping plates one and two when the specimen contracts.

[0026] 3. In this invention, to facilitate the installation of strain gauges and ensure the clamping tightness of clamps one and two during testing, the testing mechanism also includes clamp cylinder one, clamp cylinder two, connecting seat one, and connecting seat two. By controlling the controller to retract clamp cylinder one and clamp cylinder two, clamp plates two and four can be pulled out, making it easy to separate clamp plates two and four from connecting plates one and two, facilitating the installation of strain gauges on the inner side of clamp plates two and four. Similarly, by controlling the controller to extend clamp cylinder one and clamp cylinder two, clamp plates two and four can be pressed onto connecting plates one and two. Clamp plate two is connected to connecting plate two through stud two, and is also connected to clamp cylinder one through connecting seat one, which can ensure that the position of clamp plate two is fixed. Because clamp one is the fixed end during measurement.

[0027] 4. In this invention, after the specimen is completed, a sliding plate needs to be placed at the bottom of the specimen to reduce the friction at the bottom of the concrete specimen. At the same time, in order to cooperate with the placement of the sliding plate, the electric cylinder four, which is coordinated with the lifting mechanism, and the separately designed detachable lower template are used to lift and fix the specimen after jacking, and then the sliding plate is transported to the bottom of the concrete specimen. Then the lifting assembly retracts, and the electric cylinder four drives the specimen back into the testing mechanism. The whole process eliminates the hoisting and moving of the specimen, reduces the moving distance of the specimen, and reduces the damage to the specimen during the hoisting process.

[0028] 5. The present invention integrates the processes of part making, demolding, lubrication and testing, minimizing the amount of manual labor required and achieving a high degree of automation; in addition, the entire device has a three-dimensional design, reducing the floor space required. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0030] Figure 2 This is a front view structural diagram of the present invention;

[0031] Figure 3 This is a schematic diagram of the rear view structure of the present invention;

[0032] Figure 4 This is a left-side view of the present invention;

[0033] Figure 5 This is a top view of the structure of the present invention;

[0034] Figure 6 This is a schematic diagram of the structure of the present invention from a bottom view;

[0035] Figure 7 This is a partial structural schematic diagram of the testing mechanism of the present invention;

[0036] Figure 8 for Figure 7 The front view;

[0037] Figure 9 for Figure 7 Top view;

[0038] Figure 10 This is a schematic diagram of the plate-changing mechanism of the present invention.

[0039] In the diagram: Frame 10, Testing Mechanism 1, Fixture 11, Fixture 2 12, Tensile Sensor 13, Strain Gauge 14, Base Plate 1 15, Base Plate 2 16, Base Plate 3 17, Mold Mechanism 2, Upper Template 21, Lower Template 22, Side Template 23, Mold Assembly 24, Middle Plate 221, End Plate 1 222, End Plate 2 223, Plate Changing Mechanism 3, Sliding Plate 31, Plate Changing Assembly 32, Lifting Mechanism 4, Lifting Assembly 41, Controller 5, Clamping Plate 1 111, Clamping Plate 2 112, Connecting Plate 1 113, Stud 1 114, Clamping Plate 3 121, Clamping Plate 4 122, Connecting Plate 2 123, Screw Column 2 124, slide groove 125, clamping electric cylinder 18, clamping electric cylinder 2 19, connecting seat 190, connecting seat 2 191, mounting plate 241, electric cylinder 1 242, electric cylinder 2 243, electric cylinder 3 244, electric cylinder 4 245, distance sensor 246, guide slide column 247, pushing electric cylinder 321, frame 322, support plate 323, support frame 324, slide plate 325, adsorption iron block 326, electromagnet 327, pushing electric cylinder 1 411, pushing electric cylinder 2 412, pushing plate 1 413, pushing plate 2 414, support plate 1 415, support plate 2 416, through groove 417. Detailed Implementation

[0040] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0041] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," "outer," "top / bottom," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and 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. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0042] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," "sleeved / connected," "connected," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0043] Please see Figure 1-10 The present invention provides a technical solution: an ultra-high performance concrete confined shrinkage testing device, including a frame 10, a testing mechanism 1, a mold mechanism 2, a plate changing mechanism 3, a lifting mechanism 4 and a controller 5: the testing mechanism 1, the mold mechanism 2, the plate changing mechanism 3, the lifting mechanism 4 and the controller 5 are respectively connected to the frame 10.

[0044] The testing mechanism 1 is used for constrained shrinkage testing of ultra-high concrete specimens. The shrinkage testing mechanism 1 is installed in the middle of the frame 10. The testing mechanism 1 includes a first clamp 11, a second clamp 12, a tensile sensor 13, several strain gauges 14, a first base plate 15, a second base plate 16, and a third base plate 17. The first clamp 11 includes a first clamp plate 111, a second clamp plate 112, and a connecting plate 113. The bottom of the first clamp plate 111 is connected to the surface of the first base plate 15. The connecting plate 113 is installed between the first clamp plate 111 and the second clamp plate 112. One end of the connecting plate 113 is connected to the surface of the first clamp plate 111. Multiple studs 114 are connected to the end of the connecting plate 113 away from the first fixing plate. The studs 114 penetrate the second clamp plate 112. Both ends of the first base plate 15 are connected to the frame 10. The second clamp 12 includes... Clamping plates 121 and 122, and connecting plates 123 and 124 are installed between clamping plates 121 and 122. One end of connecting plate 123 is connected to the surface of clamping plate 121. Multiple studs 124 are connected to the end of connecting plate 123 away from clamping plate 121. The studs 124 penetrate clamping plate 122. Multiple sliding grooves 125 are opened on one side of clamping plate 122. Sliding blocks are slidably installed in the sliding grooves 125. One end of tension sensor 13 is connected to connecting plate 123. The end of tension sensor 13 away from connecting plate 123 is connected to frame 10. Base plate 16 is installed at the lower part of clamping plate 121. Base plate 17 is installed at the lower part of clamping plate 122. One end of base plate 16 and base plate 17 are respectively connected to frame 10.

[0045] The mold mechanism 2 cooperates with the testing mechanism 1 to cast and mold the specimen. The mold mechanism 2 includes an upper template 21, a lower template 22, two side templates 23 and a mold assembly 24. The lower template 22 includes a middle plate 221, an end plate 1 222 and an end plate 223. The end plate 1 222 and the end plate 223 are movably inserted into both sides of the middle plate 221.

[0046] The plate changing mechanism 3 is used in conjunction with the testing mechanism 1. The plate changing mechanism 3 includes a sliding plate 31 and a plate changing assembly 32. The plate changing assembly 32 includes a push cylinder 321, a frame 322, a support plate 323, multiple support frames 324, and a slide plate 325 for reducing the frictional resistance of the specimen. The frame 322 is connected to the frame 10. The support plate 323 is installed inside the frame 322. Both ends of the support plate 323 are connected to the support frames 324 and the frame 322, respectively. The slide plate 325 is slidably installed on the upper surface of the support plate 323. The slide plate 325 is a polytetrafluoroethylene plate. An adsorption iron block 326 is installed on one side of the slide plate 325. One end of the push cylinder 321 is connected to the support plate 323. An electromagnet 327 is installed on one end of the push cylinder 321. The electromagnet 327 is connected to the controller 5.

[0047] The lifting mechanism 4 is used to lift the concrete specimen. The lifting mechanism 4 includes two lifting components 41, which are respectively installed on both sides of the testing mechanism 1. The lifting component 41 includes a first propulsion cylinder 411, a second propulsion cylinder 412, a first propulsion plate 413, a second propulsion plate 414, a first support plate 415, and a second support plate 416. The first support plate 415 is located on the side of the first propulsion plate 413 away from the first propulsion cylinder 411. The first support plate 415 and the first propulsion plate 416 are connected. 413 is hinged, and the second support plate 416 is located on the side of the second push plate 414 away from the second push cylinder 412. The second support plate 416 and the second push plate 414 are hinged. The first push cylinder 411 is installed on one side of the first connecting plate 113. One end of the first push cylinder 411 is connected to the first push plate 413. An installation platform is installed on the lower part of the first push cylinder 411. The lower part of the installation platform is connected to the first base plate 15. The first support plate 415 is located on the upper part of the first connecting plate 113.

[0048] Strain gauges 14 are respectively installed on the inner surfaces of clamping plates 111, 112, 121, and 122; strain gauges 14 and tension sensors 13 are respectively connected to external data acquisition devices.

[0049] One end of the clamping plate 111, clamping plate 212, clamping plate 321 and clamping plate 422 is equipped with a plug 6, and the two ends of the side template 23 are respectively provided with slots 7 that cooperate with the plug 6.

[0050] The testing mechanism 1 also includes a clamping electric cylinder 18, a clamping electric cylinder 19, a connecting seat 190, and a connecting seat 191. The lower part of the clamping electric cylinder 18 is connected to the base plate 15, one end of the clamping electric cylinder 18 is hinged to the connecting seat 190, and one end of the connecting seat 190 is connected to the clamping plate 212. The lower part of the clamping electric cylinder 219 is connected to the base plate 317, one end of the connecting seat 2191 is connected to the sliding block, and the end of the connecting seat 2191 away from the clamping plate 4122 is connected to the clamping electric cylinder 219. The clamping electric cylinder 18 and the clamping electric cylinder 219 are respectively connected to the controller 5.

[0051] The module assembly 24 includes a mounting plate 241, electric cylinder 1 242, electric cylinder 243, electric cylinder 3 244, electric cylinder 4 245, a distance sensor 246, and multiple guide slides 247. Both ends of the mounting plate 241 are connected to the frame 10. Electric cylinder 1 242 is mounted on the upper part of the mounting plate 241, and its lower part penetrates the mounting plate 241 to connect with the upper template 21. Electric cylinders 243 and 244 are mounted on one side of electric cylinder 1 242, and their lower parts penetrate the mounting plate 241 to connect with the upper template 21. Plate 241 is connected to the corresponding side template 23 respectively. The lower part of multiple guide slides 247 penetrates the mounting plate 241 and is connected to the corresponding side template 23 respectively. Anti-detachment plates are installed on the upper part of the guide slides 247. The upper part of electric cylinder 245 is connected to the lower template 22, and the lower part of electric cylinder 245 is connected to the frame 10. Distance sensor 246 is installed on one side of electric cylinder 245. Distance sensor 246, electric cylinder 1 242, electric cylinder 2 243, electric cylinder 3 244 and electric cylinder 4 245 are respectively connected to controller 5.

[0052] The second propulsion cylinder 412 is installed on one side of the second connecting plate 123. The lower part of the second propulsion cylinder 412 is connected to the frame 10. The second propulsion plate 414 is connected to one end of the second propulsion cylinder 412. The lower part of the second propulsion plate 414 has a through groove 417 that cooperates with the tension sensor 13. The second support plate 416 is located on the upper part of the second connecting plate 123. The first propulsion cylinder 411 and the second propulsion cylinder 412 are respectively connected to the controller 5.

[0053] Working principle: The upper template 21, lower template 22, and two side templates 23 in the mold mechanism 2 are combined with clamp 11 and clamp 22 to form a mold for casting specimens. The structure of this mold is wide at both ends and narrow in the middle. The high-performance concrete specimens produced also have a structure that is wide at both ends and narrow in the middle, which makes it easy to clamp them with clamp 11 and clamp 22 during end constraint testing.

[0054] The specific assembly process is as follows: First, the controller 5 controls the start of electric cylinder 243 and electric cylinder 3 244. Electric cylinder 243 and electric cylinder 3 244 extend, driving the two side templates 23 to move downward. The two ends of one side template 23 are connected to clamping plate 111 and clamping plate 3121, and the two ends of the other side template are connected to clamping plate 212 and clamping plate 4122. The anti-detachment plate plays a role in limiting the downward movement distance of the side template 23.

[0055] Then, the controller 5 controls the start of the electric cylinder 245. After the electric cylinder 245 extends, it drives the lower template 22 to move upward, transporting the lower template 22 between the two side templates 23 to complete the assembly of the bottom of the mold; then concrete is poured in.

[0056] Finally, the controller 5 activates the electric cylinder 242, which in turn moves the upper template 21 downwards, pressing it against the top of the concrete. This allows for the fabrication of the test specimen. During specimen fabrication, strain gauge 14 can be omitted; it is installed only during testing.

[0057] Before testing, demolding is required. First, controller 5 activates electric cylinders 242, 243, and 244 to pull the upper template 21 and the two side templates 23 upwards. Then, electric cylinder 245 is activated to extend it further, dragging the specimen upwards. Simultaneously, controller 5 activates pusher cylinders 411 and 412 to push support plates 415 and 416 towards the specimen. When the upward-moving specimen contacts support plates 415 and 416, it pushes them upwards and flips them over. After the specimen is separated from the support plate 1 415 and support plate 2 416, the tester pulls out the end plate 1 222 and end plate 2 223 from both sides. Then, the controller 5 controls the electric cylinder 4 245 to retract, which drives the middle plate 221 and the specimen above it to move downward. The specimen is supported by the support plates 1 415 and support plate 2 416 on both sides. The support plates 1 415 and support plate 2 416 are respectively hinged to the push plate 1 413 and push plate 2 414. When flipping downward, the specimen is supported by the connecting plate 1 113 and connecting plate 2 123.

[0058] The intermediate plate 221 moves downward onto the support frame 324. At this time, the controller 5 starts the push cylinder 321 to push the slide plate 325 to the upper part of the intermediate plate 221. The controller 5 controls the electromagnet 327 to be de-energized and starts the electric cylinder 245 again. The intermediate plate 221 drives the slide plate 325 to move upward. The distance sensor 246 measures the moving distance of the intermediate plate 221, so that the controller 5 can control the rising height of the intermediate plate 221.

[0059] After the intermediate plate 221 drives the sliding plate 31 to the actual bottom and stops, the controller 5 controls the first propulsion cylinder 411 and the second propulsion cylinder 412 to retract and put the specimen down; then the controller controls the fourth cylinder 245 to drive the specimen to move into the first clamp 11 and the second clamp 12; by installing the sliding plate 31, the friction at the bottom of the specimen can be reduced, ensuring the reliability of the test.

[0060] At this point, strain gauges 14 have been installed on the inner surfaces of clamping plates 111, 112, 121, and 122. To facilitate the installation of strain gauges 14 and ensure the clamping tightness of the fixtures during testing, the testing mechanism 1 also includes clamping cylinders 18 and 19, connecting seat 190 and 191. Since studs 114 and 124 penetrate clamping plates 112 and 122, they can serve as guides. By activating the controller 5 to retract clamping cylinders 18 and 190, clamping plates 112 and 122 can be pulled out, allowing clamping plates 112 and 122 to extend. 112 and clamping plate four 122 are easily separated from connecting plate one 113 and connecting plate two 123, facilitating the installation of strain gauge 14 on the inner side of clamping plate two 112 and clamping plate four 122; similarly, by controlling the extension of clamping cylinder one 18 and clamping cylinder two 19 through controller 5, clamping plate two 112 and clamping plate four 122 can be pressed onto connecting plate one 113 and connecting plate two 123. Clamping plate two 112 is connected to connecting plate two 123 through stud two 124, and is also connected to clamping cylinder one 18 through connecting seat one 190, which can ensure that the position of clamping plate two 112 is fixed; because clamp one 11 is the fixed end during measurement.

[0061] Connector 2 191 is connected to sliding column, which can slide within slide groove 125, thereby ensuring the mobility of clamp 4 122 and not affecting the movement of clamp 2 12.

[0062] The force on one end of the clamp 12 is measured by the tension sensor 13, and the force on the clamp is measured by the strain gauge 14 to reflect the shrinkage characteristics of the specimen. The data measured by the tension sensor 13 and the strain gauge 14 are transmitted to the external data acquisition instrument to complete the data collection.

[0063] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0064] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A test device for confined shrinkage of ultra-high performance concrete, comprising a frame (10), characterized in that: Also includes: The testing mechanism (1) is used for constrained shrinkage testing of ultra-high concrete specimens. The testing mechanism (1) is located in the middle of the frame (10). The testing mechanism (1) includes clamp one (11), clamp two (12), tension sensor (13), several strain gauges (14), base plate one (15), base plate two (16) and base plate three (17). The clamp one (11) includes clamp plate one (111), clamp plate two (112) and connecting plate one (17). 13), the bottom of the first clamping plate (111) is connected to the surface of the first base plate (15), the second clamping fixture (12) includes a third clamping plate (121), a fourth clamping plate (122) and a second connecting plate (123), the second connecting plate (123) is disposed between the third clamping plate (121) and the fourth clamping plate (122), and a plug (6) is installed at one end of the first clamping plate (111), the second clamping plate (112), the third clamping plate (121) and the fourth clamping plate (122); The mold mechanism (2), in conjunction with the testing mechanism (1), is used for casting and molding of the specimen. The mold mechanism (2) includes an upper template (21), a lower template (22), multiple side templates (23), and a mold assembly (24). The side templates (23) have slots (7) at both ends that mate with the insert blocks (6). The lower template (22) includes a middle plate (221), an end plate one (222), and an end plate two (223). The end plate one (222) and the end plate two (223) are movably inserted into both sides of the middle plate (221). The mold assembly (24) includes a mounting plate (241), an electric cylinder one (242), an electric cylinder two (243), an electric cylinder three (244), an electric cylinder four (245), a distance sensor (246), and multiple guide slides (247). The plate changing mechanism (3) is used in conjunction with the testing mechanism (1). The plate changing mechanism (3) includes a sliding plate (31) and a plate changing assembly (32). The plate changing assembly (32) includes a push cylinder (321), a frame (322), a support plate (323), multiple support frames (324), and a sliding plate (325) for reducing the frictional resistance of the specimen. The lifting mechanism (4) is used to lift concrete specimens. The lifting mechanism (4) includes multiple lifting components (41). The multiple lifting components (41) are respectively arranged on both sides of the testing mechanism (1). The lifting components (41) include a first propulsion cylinder (411), a second propulsion cylinder (412), a first propulsion plate (413), a second propulsion plate (414), a first support plate (415), and a second support plate (416). The controller (5) is connected to the test mechanism (1), mold mechanism (2), plate changing mechanism (3) and lifting mechanism (4). Start the electric cylinder four (245) to extend it and drag the specimen upward; start the propulsion electric cylinder one (411) and propulsion electric cylinder two (412) through the controller (5) to push the pallet one (415) and pallet two (416) towards the specimen; The controller (5) controls the retraction of the electric cylinder four (245), which drives the middle plate (221) and the specimen above it to move downward, and supports the specimen through the two side support plates one (415) and two support plates two (416); The controller (5) starts the push cylinder (321) to push the slide plate (325) to the upper part of the middle plate (221), and then starts the fourth electric cylinder (245) again to drive the slide plate (325) upward through the middle plate (221); The controller (5) controls the retraction of the first propulsion cylinder (411) and the second propulsion cylinder (412) to lower the specimen; Control cylinder four (245) to move the specimen into fixture one (11) and fixture two (12); The testing mechanism (1), mold mechanism (2), plate changing mechanism (3), lifting mechanism (4) and controller (5) are respectively connected to the frame (10).

2. The ultra-high performance concrete restrained shrinkage testing device according to claim 1, characterized in that: The connecting plate 1 (113) is disposed between the clamping plate 1 (111) and the clamping plate 2 (112). One end of the connecting plate 1 (113) is connected to the surface of the clamping plate 1 (111). A plurality of studs 1 (114) are connected to the end of the connecting plate 1 (113) away from the clamping plate 1 (111). The studs 1 (114) penetrate the clamping plate 2 (112). The two ends of the base plate 1 (15) are respectively connected to the frame (10).

3. The ultra-high performance concrete restrained shrinkage testing device according to claim 1, characterized in that: One end of the connecting plate 2 (123) is connected to the surface of the clamping plate 3 (121). The end of the connecting plate 2 (123) away from the clamping plate 3 (121) is connected to a plurality of studs 2 (124). The studs 2 (124) penetrate the clamping plate 4 (122). A plurality of sliding grooves (125) are provided on one side of the clamping plate 4 (122). A sliding block is slidably arranged in the sliding groove (125). One end of the tension sensor (13) is connected to the connecting plate 2 (123). The end of the tension sensor (13) away from the connecting plate 2 (123) is connected to the frame (10). The bottom plate 2 (16) is located at the lower part of the clamping plate 3 (121). The bottom plate 3 (17) is located at the lower part of the clamping plate 4 (122). One end of the bottom plate 2 (16) and the bottom plate 3 (17) are respectively connected to the frame (10).

4. The ultra-high performance concrete restrained shrinkage testing device according to claim 3, characterized in that: Multiple strain gauges (14) are respectively disposed on the inner surfaces of clamping plate one (111), clamping plate two (112), clamping plate three (121) and clamping plate four (122); the strain gauges (14) and the tension sensor (13) are respectively connected to an external data acquisition device.

5. The ultra-high performance concrete restrained shrinkage testing device according to claim 4, characterized in that: The testing mechanism (1) further includes a clamping electric cylinder one (18), a clamping electric cylinder two (19), a connecting seat one (190) and a connecting seat two (191). The lower part of the clamping electric cylinder one (18) is connected to the base plate one (15), one end of the clamping electric cylinder one (18) is hinged to the connecting seat one (190), and one end of the connecting seat one (190) is connected to the clamping plate two (112). The lower part of the clamping electric cylinder two (19) is connected to the base plate three (17), one end of the connecting seat two (191) is connected to the sliding block, and the end of the connecting seat two (191) away from the clamping plate four (122) is connected to the clamping electric cylinder two (19). The first clamping electric cylinder (18) and the second clamping electric cylinder (19) are respectively connected to the controller (5).

6. The ultra-high performance concrete restrained shrinkage testing device according to claim 1, characterized in that: The two ends of the mounting plate (241) are respectively connected to the frame (10). The first electric cylinder (242) is set on the upper part of the mounting plate (241), and the lower part of the first electric cylinder (242) passes through the mounting plate (241) and is connected to the upper template (21). The second electric cylinder (243) and the third electric cylinder (244) are set on one side of the first electric cylinder (242). The lower parts of the second electric cylinder (243) and the third electric cylinder (244) pass through the mounting plate (241) and are respectively connected to the corresponding side templates (23). The lower part of the plurality of guide slides (247) The through mounting plate (241) is connected to the corresponding side template (23) respectively. The upper part of the guide slide (247) is provided with an anti-detachment plate. The upper part of the electric cylinder four (245) is connected to the lower template (22), and the lower part of the electric cylinder four (245) is connected to the frame (10). The distance sensor (246) is set on one side of the electric cylinder four (245). The distance sensor (246), electric cylinder one (242), electric cylinder two (243), electric cylinder three (244) and electric cylinder four (245) are respectively connected to the controller (5).

7. The ultra-high performance concrete restrained shrinkage testing device according to claim 1, characterized in that: The frame (322) is connected to the frame (10), the support plate (323) is set inside the frame (322), the two ends of the support plate (323) are respectively connected to the support frame (324) and the frame (322), the slide plate (325) is slidably set on the upper surface of the support plate (323), the slide plate (325) is a polytetrafluoroethylene plate, an adsorption iron block (326) is provided on one side of the slide plate (325), one end of the push cylinder (321) is connected to the support plate (323), one end of the push cylinder (321) is provided with an electromagnet (327), and the electromagnet (327) is connected to the controller (5).

8. The ultra-high performance concrete restrained shrinkage testing device according to claim 2, characterized in that: The first support plate (415) is located on the side of the first push plate (413) away from the first push cylinder (411), and the first support plate (415) is hinged to the first push plate (413). The second support plate (416) is located on the side of the second push plate (414) away from the second push cylinder (412), and the second support plate (416) is hinged to the second push plate (414). The first push cylinder (411) is set on one side of the first connecting plate (113), and one end of the first push cylinder (411) is connected to the first push plate (413). The lower part of the first push cylinder (411) is provided with a mounting platform, and the lower part of the mounting platform is connected to the first base plate (15). The first support plate (415) is located on the upper part of the first connecting plate (113). The second propulsion cylinder (412) is located on one side of the second connecting plate (123). The lower part of the second propulsion cylinder (412) is connected to the frame (10). The second propulsion plate (414) is connected to one end of the second propulsion cylinder (412). The lower part of the second propulsion plate (414) is provided with a through groove (417) that cooperates with the tension sensor (13). The second support plate (416) is located on the upper part of the second connecting plate (123). The first propulsion cylinder (411) and the second propulsion cylinder (412) are respectively connected to the controller (5).

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