Same-condition test block creep characteristic detection equipment based on test block storage vehicle

Abstract

The invention discloses same-condition test block creep characteristic detection equipment based on a test block storage vehicle, and relates to the technical field of concrete construction creep detection, and the same-condition test block creep characteristic detection equipment comprises a combined casting mold which is provided with two semi-symmetrical mechanisms and is suitable for linear opening and closing to switch a splicing state and a demolding state; the output end of the dead load applying mechanism is connected with a top template with a pressure sensor; applying constant pressure as a pressurizing head after demoulding; the measurement compensation mechanism comprises a low-expansion reference rod with the bottom end anchored to the movable bearing chassis and the top end freely extending, and the linear expansion coefficient of the low-expansion reference rod is smaller than that of the pressure-bearing stand column; the displacement acquisition unit is fixed at the top end of the reference rod and used for acquiring axial displacement of the pressed test block relative to the top end of the reference rod; the control unit is used for adjusting the output of the dead load applying mechanism according to the feedback of the pressure sensor so as to maintain the constant pressure, and calculating the creep according to the displacement data, so that the high precision of the creep characteristic acquisition of the pressed test block and the consistency of the same-condition environment of the building are realized, and the creep detection precision is improved.

Description

Technical Field

[0001] This invention relates to the field of concrete creep testing technology, specifically to a device for testing the creep characteristics of test blocks under the same conditions based on a test block storage vehicle. Background Technology

[0002] Concrete creep refers to the increase in inelastic deformation of concrete under long-term constant load over time. It has a decisive impact on the long-term deflection and safety of prestressed structures such as super high-rise buildings and long-span bridges. Therefore, accurately obtaining the creep coefficient of concrete for a specific project is crucial.

[0003] Currently, existing creep testing technologies mainly employ standard laboratory testing methods, which involve applying constant pressure to the test block using a creep meter in a standard curing room with constant temperature and humidity. However, this offline testing mode has three major technical challenges:

[0004] Lack of environmental isomorphism: The laboratory environment cannot simulate the complex solar radiation, drastic temperature differences, and wind speed and humidity fluctuations at the construction site, resulting in a serious disconnect between the measured creep data and the actual mechanical evolution process of the building, thus reducing its reference value.

[0005] The problem of temperature drift in mobile equipment: To solve the above problem, attempts were made to move the testing equipment to the outdoor field. However, the frame of the existing mobile testing equipment will undergo significant thermal expansion deformation after being heated outdoors. This deformation will not only cause the pressure of the loading system to relax, but also cause the measurement reference of the displacement sensor to drift, so that the micron-level creep signal is drowned out by the environmental thermal noise.

[0006] Early disturbance and loading eccentricity: Traditional methods require the specimens to be molded in a mold, and after demolding, they need to be manually transported and installed on the creep meter. For early-age concrete, vibration during transportation and centering errors during installation can damage its fragile internal hydration structure, leading to unexpected microcracks in the specimens. This "artificial disturbance" is completely inconsistent with the stress state of in-situ casting and static operation of building components.

[0007] Therefore, there is an urgent need for a test block creep characteristic detection device based on a test block storage vehicle that can move with the construction progress, achieve automatic temperature compensation in a fully open environment, and achieve zero-disturbance transition from pouring to loading. Summary of the Invention

[0008] This invention provides a test device for detecting the creep characteristics of test blocks under the same conditions based on a test block storage vehicle, which can achieve the effects of in-situ casting, phase change sealing, coaxial loading, and avoidance of the influence of temperature changes.

[0009] A device for testing the creep characteristics of test blocks under the same conditions based on a test block storage vehicle includes:

[0010] Mobile load-bearing chassis, used for free movement and parking on the construction site;

[0011] The loading gantry frame is installed on a mobile load-bearing chassis and includes a top beam, a bottom beam, and several vertically arranged pressure-bearing columns;

[0012] The modular casting mold includes two symmetrical halves set on the pressure-bearing column, which are suitable for linear opening and closing to switch between the assembly and demolding states. An elastic compensation base is provided above the bottom beam, which seals and encloses the symmetrical mechanism when assembled.

[0013] The constant load application mechanism is installed on the top beam, and the output end is connected to the top template with a pressure sensor; in the assembled state, the top template abuts against the symmetrical mechanism to form a closed cavity, and after demolding, it acts as a pressure head to apply constant pressure;

[0014] The measurement and compensation mechanism includes a low-expansion reference rod with its bottom end anchored to a movable bearing chassis and its top end extending freely. Its coefficient of linear expansion is less than that of the bearing column. The displacement acquisition unit is fixed to the top of the reference rod and is used to acquire the axial displacement of the compressed test block relative to the top of the reference rod.

[0015] The control unit is used to adjust the output of the constant load application mechanism to maintain constant pressure based on feedback from the pressure sensor, and to calculate creep based on displacement data.

[0016] Furthermore, the mobile load-bearing chassis includes a chassis body, and an active leveling mechanism is provided at the four corners of the bottom of the chassis body. The active leveling mechanism includes four independently controlled horizontal adjustment legs and a level sensor located at the center of the chassis body. The control unit is electrically connected to the level sensor and each horizontal adjustment leg, and is used to drive each horizontal adjustment leg to extend and retract based on the level data so that the chassis body maintains a level posture.

[0017] Furthermore, the electric horizontal outrigger includes a pole sleeve fixed to the bottom of the chassis body, with a ball joint cavity at the bottom of the pole sleeve; it also includes a telescopic foot support, the end of the telescopic rod of the telescopic foot support extending into the ball joint cavity and hinged to the pole sleeve via a ball joint; the control unit controls the axial extension and retraction of the telescopic foot support relative to the pole sleeve.

[0018] Furthermore, a flexible tensioning plate is provided inside the ball joint movable cavity, which is laterally tensioned within the ball joint movable cavity. The telescopic rod of the telescopic foot passes through the central hole of the flexible tensioning plate. The flexible tensioning plate is suitable for limiting the radial swing of the telescopic foot and allowing the telescopic foot to tilt at multiple angles around the ball head.

[0019] Furthermore, the top edge of the positioning plate is provided with an integrally formed recess, and the symmetrical mechanism includes a lower template and an upper template that are interlocked with each other. The lower template has a flange at the bottom corresponding to the recess, a groove at the top, and a tongue at the bottom corresponding to the groove. The top of the upper template abuts against the top template to form a closed cavity.

[0020] Furthermore, the positioning plate recess is provided with a hot-melt phase change seal, including an integrated elastic sealing bladder and a heating device. The elastic sealing bladder is filled with phase change wax, and the heating device is electrically connected to the control unit to control the phase change wax to melt into a liquid state before the mold is assembled, and to stop heating after assembly to allow the phase change wax to solidify and set.

[0021] Furthermore, the control unit is configured to perform the following sealing steps: upon receiving a mold assembly command, the heating device is activated to heat for a preset time, and after the phase change wax softens, the symmetrical mechanism is driven to close; then the heating is stopped, and the solidified phase change wax is used to fill the micro-assembly gap between the lower template and the positioning plate.

[0022] Furthermore, the pressure-bearing column is equipped with a track, and a push-pull plate is slidably mounted on the track. The push-pull plate is connected to the lower template and is suitable for driving the lower and upper templates of the symmetrical mechanism to open and close radially.

[0023] Furthermore, the upper and lower templates are respectively equipped with detachable buckles. When the detachable buckles are unlocked, the symmetrical mechanism can move freely and linearly along the track. After assembly, the movement of the symmetrical mechanism can be restricted by locking the detachable buckles.

[0024] Furthermore, the testing equipment has a measurement configuration state; in the measurement configuration state, the upper template is removed, exposing the top of the pressure test block; the top template acts directly on the top surface of the pressure test block as a loading head; the displacement acquisition unit collects the height displacement data of the pressure test block in a non-contact manner.

[0025] The beneficial effects of the above-described technical solutions provided in the embodiments of the present invention include at least the following:

[0026] 1. By setting a low-expansion reference rod anchored to the mobile load-bearing chassis with an extremely low coefficient of linear expansion, an absolutely static reference system is provided for the displacement acquisition unit, which is not affected by the thermal expansion of the vehicle frame. This physically filters out the measurement error caused by the thermal elongation of the mobile load-bearing chassis. This allows the equipment to perform testing in harsh environments such as construction sites exposed to scorching sun or with large temperature differences between day and night, achieving environmental monitoring similar to that of the building being measured, and obtaining pure and accurate creep data.

[0027] 2. An integrated mold and pressure head design is adopted. The top formwork serves as the cover of the closed mold during the pouring stage and directly transforms into a pressure head for applying loads during the testing stage. Combined with a two-half symmetrically opening and closing composite pouring mold, in-situ demolding and in-situ loading are achieved. This scheme completely eliminates the internal damage and eccentric compression risks caused by demolding, handling, and secondary centering installation in traditional testing of early-age compression specimens. It maximizes the reproduction of the true state of building components formed in one go and subjected to in-situ stress, making the creep data more closely reflect the actual condition of the building.

[0028] 3. On the other hand, the active leveling mechanism installed on the mobile bearing chassis can automatically adjust the level based on the horizontal state of the mobile bearing chassis, so as to keep the load on the pressure test block vertical, eliminate the error caused by the angle deviation, and maintain the detection accuracy of creep data.

[0029] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the written description, claims, and drawings.

[0030] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0031] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0032] Figure 1 This is a schematic diagram of the structure of the detection device disclosed in an embodiment of the present invention;

[0033] Figure 2 This is a schematic diagram of the internal structure of the detection device disclosed in an embodiment of the present invention;

[0034] Figure 3 This is a schematic diagram showing the positional relationship between the loading gantry, the combined casting mold, and the constant load application mechanism disclosed in an embodiment of the present invention.

[0035] Figure 4 for Figure 3 Schematic diagram of partial cross-section of the structure;

[0036] Figure 5 for Figure 4 Enlarged structural diagram at point A;

[0037] Figure 6 for Figure 4 A structural diagram showing the structure after the upper formwork is removed and the lower formwork is moved.

[0038] Figure 7 This is a cross-sectional view of the measurement compensation structure disclosed in an embodiment of the present invention;

[0039] Figure 8 This is a cross-sectional view of the horizontally adjustable outrigger disclosed in an embodiment of the present invention;

[0040] Figure 9 This is a communication block diagram of the detection device disclosed in an embodiment of the present invention.

[0041] Figure label:

[0042] 1. Mobile load-bearing chassis; 11. Chassis body; 12. Grid cover; 13. Wheels; 14. Horizontal adjustable outriggers; 141. Upright sleeve; 1411. Movable groove; 142. Telescopic foot support; 1421. Ball head; 143. Flexible tensioning plate; 2. Loading gantry; 21. Pressure-bearing column; 22. Bottom beam; 23. Top beam; 24. Baffle; 3. Modular casting mold; 31. Elastic compensation base; 311. Telescopic sleeve; 312. Elastic component; 32. Positioning plate; 321. Recess; 33. Lower template; 331. Flange; 332. 34. Groove; 341. Upper template; 35. Tongue; 36. Top template; 37. Hot melt phase change seal; 38. Elastic sealing bladder; 39. Phase change wax; 30. Heating device; 31. Removable buckle; 32. Track; 33. Push-pull plate; 4. Constant load application mechanism; 44. Telescopic cylinder; 45. Pressure sensor; 6. Measurement compensation structure; 76. Mounting base; 87. Low expansion reference rod; 98. Displacement acquisition unit; 10. Protective sleeve; 11. Through hole; 12. Control unit; 13. Pressure test block; 14. User terminal; 15. Horizontal sensor. Detailed Implementation

[0043] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0044] Overall architecture as follows Figure 2 As shown, the main body of this equipment includes a mobile load-bearing chassis 1, a loading gantry frame 2, a combined casting mold 3, a constant load application mechanism 4, and a measurement and compensation structure 5.

[0045] The following sections will explain each of the main structural components.

[0046] like Figure 1 and 2As shown, the mobile support chassis 1 is used to move and park freely on the construction site. Considering the actual environment of the construction site, after the mobile support chassis 1 is parked, its horizontal position also needs to be considered to ensure the accuracy of creep detection data. Therefore, the following settings are made for the environment in which the mobile support chassis 1 is used: The mobile support chassis 1 includes a chassis body 11. An active leveling mechanism is provided at the four corners of the bottom of the chassis body 11. The active leveling mechanism includes four independently controlled horizontal adjustment legs 14 and a horizontal sensor 9 set at the center of the chassis body 11. The control unit 6 is electrically connected to the horizontal sensor 9 and each horizontal adjustment leg 14, and is used to drive each horizontal adjustment leg 14 to extend and retract based on the horizontal data so that the chassis body 11 maintains a horizontal posture.

[0047] Specifically, the electric horizontal outrigger includes a pole sleeve 141 fixed to the bottom of the chassis body 11, with a ball joint cavity at the bottom of the pole sleeve 141; it also includes a telescopic foot support 142, with the telescopic rod end of the telescopic foot support 142 extending into the ball joint cavity and hinged to the pole sleeve 141 via a ball head 1421; the control unit 6 controls the telescopic foot support 142 to extend and retract axially relative to the pole sleeve 141.

[0048] The control unit 6 identifies the horizontal state of the chassis body 11 based on the data obtained by the horizontal sensor 9. When it is identified that the chassis body 11 is not horizontal, the control unit 6 adjusts the extension length of the horizontal adjustment legs 14 and the telescopic foot support 142 based on the acquired data to adjust the chassis body 11 to a horizontal state. The advantage of doing so is that it can avoid the load axis of the pressure test block 7 from being deviated. Since creep displacement is a micron-level precision physical quantity, any deviation of the load axis will cause stress gradient and additional bending moment to be generated inside the pressure test block 7, inducing unexpected stress bending and local cracking, which seriously interferes with the accurate extraction of the creep coefficient. This scheme for adjusting the level of the chassis body 11 uses a closed-loop leveling system consisting of leveling support legs 14 and level sensor 9 to ensure that the support surface of the chassis body 11 is always perpendicular to the direction of gravity vector. This ensures the absolute coincidence of the constant load and the centroidal axis of the pressure test block 7, eliminating measurement noise caused by eccentric pressure. The telescopic support 142 uses existing hydraulic cylinder telescopic support 142 or electric telescopic support 142. The control unit 6 controls the telescopic support 142's extension and retraction based on the data obtained by the level sensor 9, which also uses existing technology. Its working principle will not be described in detail here.

[0049] like Figure 8 As shown, a flexible tensioning plate 143 is also provided in the ball joint movable cavity, which is laterally tensioned in the ball joint movable cavity. The telescopic rod of the telescopic foot support 142 passes through the central hole of the flexible tensioning plate 143. The flexible tensioning plate 143 is adapted to limit the radial swing of the telescopic foot support 142 and allow the telescopic foot support 142 to tilt at multiple angles around the ball head 1421.

[0050] The flexible tensioning plate 143 is made of EPDM rubber and polyurethane elastomer, and its overall structure is a ring-shaped corrugated structure. The radial cross section of the corrugated structure is a continuous S-shape or wave shape. Utilizing the high elongation of the rubber material and the geometric avoidance characteristics of the corrugated structure, the bending moment resistance generated by the tensioning plate is less than the driving force of the outrigger when the telescopic support 142 is tilted around the ball head 1421, ensuring a smooth leveling process. At the same time, relying on the stress relaxation characteristics and rebound memory of the elastomer material after being stretched, the tensioning plate pulls the telescopic support 142 back to the initial axis position through the full-circumferential elastic contraction force when the horizontal adjustment outrigger 14 is unloaded. Meanwhile, the flexible tensioning plate 143 not only achieves the centering function, but also acts as a physical barrier to prevent mud and dust from the construction site from entering the hinge space of the ball head 1421 at the bottom, thus extending the service life of the component.

[0051] like Figures 1-2 As shown, the chassis body 11 can also be equipped with a fully enclosed grid cover 12 to enclose the loading gantry 2, the combined casting mold 3, the constant load application mechanism 4, and the measurement compensation structure 5 inside. The grid cover 12 adopts a grid structure with a high open area ratio, which can act as a rigid barrier to block external gravel, impacts, and unauthorized personnel from interfering with the creep test at the physical level. At the environmental level, the air convection effect and light transmission characteristics are used to ensure that the temperature, humidity, and wind speed conditions of the test block inside the cover are synchronized with the building location in real time. At the same time, the bottom of the chassis body 11 is also equipped with wheels 13 for moving the chassis body 11 to a suitable position. After reaching the appropriate position, the control unit 6 controls the telescopic support 142 to extend and lift the wheels 13, and adjust the level of the support surface of the chassis body 11. After the test is completed, the control unit 6 controls the telescopic support 142 to retract, and the wheels 13 support the chassis body 11.

[0052] like Figures 2-3 As shown, the loading gantry 2 is installed on the mobile bearing chassis 1, including a top beam 23, a bottom beam 22 and several vertically arranged pressure-bearing columns 21. Its function is to serve as a carrier for the combined casting mold 3 and the constant load application mechanism 4, so as to realize in-situ casting, in-situ demolding and in-situ loading.

[0053] like Figures 2-6 As shown, the combined casting mold 3 includes two symmetrical mechanisms set on the pressure-bearing column 21, which are suitable for linear opening and closing to switch between the assembly and demolding states. An elastic compensation base 31 is provided above the bottom beam 22, which is sealed and enclosed with the symmetrical mechanism when assembled.

[0054] The positioning plate 32 has a recess 321 integrally formed on its top edge. The symmetrical mechanism includes a lower template 33 and an upper template 34 that are interlocked. The lower template 33 has a flange 331 at the bottom corresponding to the recess 321 and a groove 332 at the top. The upper template 34 has a tongue 341 at the bottom corresponding to the groove 332. The top of the upper template 34 abuts against the top template 35 to form a closed cavity.

[0055] The concrete used in the construction is poured into a closed cavity simultaneously to prepare the pressure test block 7. Because concrete creep testing has a long cycle, any slight leakage of grout or loss of moisture can cause uncontrollable shrinkage deformation in the test block. To obtain accurate creep test data, the hot-melt phase change seal 36 of this invention uses a rigid barrier formed by solid paraffin wax to ensure a constant water-cement ratio inside the cavity, thereby achieving physical isolation between creep and shrinkage data and improving testing accuracy. Specifically, the hot-melt phase change seal 36 is provided in the recess 321 of the positioning plate 32, including an integrated elastic sealing bladder 361 and a heating device 363. The elastic sealing bladder 361 is filled with phase change wax 362. The heating device 363 is electrically connected to the control unit 6 to control the phase change wax 362 to melt into a liquid state before mold assembly and to stop heating after assembly to allow the phase change wax 362 to solidify and set. Specifically, as shown... Figure 9 As shown, the control unit 6 is configured to perform the following sealing steps: upon receiving the mold assembly command, the heating device 363 is activated to heat for a preset time, and after the phase change wax 362 softens, the symmetrical mechanism is driven to close; then the heating is stopped, and the solidified phase change wax 362 is used to fill the micro-assembly gap between the lower template 33 and the positioning plate 32.

[0056] The elastic sealing bladder 361 adopts a double-layer composite structure: the inner layer is a metal braided mesh with good thermal conductivity, used to evenly diffuse the heat of the heating device 363; the outer layer is heat-resistant fluororubber. After receiving the mold closing command, the control unit 6 activates the heating device 363 inside the electroelastic sealing bladder 361. The heating device 363 uses a heating wire and heating patch, which is set on one side inside the elastic sealing bladder 361. The outer side of this side is fixedly connected to the recess 321. The heating device 363 heats the phase change wax 362 to above its phase change temperature, causing the elastic sealing bladder 361 to transform into a compressible plastic fluid state. In the softened state, it drives the symmetrical mechanism to perform a linear closing action. At this time, the plastic fluid paraffin wax fills the lower mold under extrusion. Within the micro-rough surface between plate 33 and the recess 321 of positioning plate 32, the detachable buckle 36 is locked, fixing the two halves of the symmetrical mechanism. Control unit 6 cuts off the power to heating device 363. Phase change wax 362 recovers solid hardness as heat dissipates, and uses physical volume compensation during the phase change process to apply a continuous active sealing load to the sealing interface, completing the absolute sealing preparation before the pressure test block 7 is poured. It should be noted that the melting point of phase change wax 362 is higher than the highest exothermic temperature of pressure test block 7 during the hydration and hardening process. The hot melt phase change sealing assembly also includes a heat insulation shielding layer covering the outer periphery of elastic sealing bladder 361. The detachable buckle 36 uses the existing two-half buckle, and its locking mechanism is used to achieve unlocking and locking.

[0057] like Figure 3 , 4 As shown in Figure 6, a track 37 is provided on the pressure-bearing column 21, and a push-pull plate 38 is slidably mounted on the track 37. The push-pull plate 38 is connected to the lower template 33. The push-pull plate 38 is suitable for driving the lower template 33 and the upper template 34 of the symmetrical mechanism to open and close radially. The push-pull plate 38 and the track 37 adopt a mating structure similar to a dovetail groove, so as to realize the radial movement of the push-pull plate 38 along the track 37 while preventing the push-pull plate 38 from dislodging from the track 37. Figure 4 As shown, the push-pull plate 38 is connected to the lower template 33. Before the top template 35 is pressed down, the two halves of the symmetrical mechanism are assembled or separated by pulling the push-pull plate 38. For ease of description, after the lower template 33 is connected to the upper template 34, its whole is described as a side template.

[0058] Two stacked side formwork panels can be joined together to form a closed cavity with the positioning plate 32. After injecting concrete of the same type as the building into the closed cavity, the top formwork 35 is pressed down to seal the closed cavity. After the demolding conditions are met, the top formwork 35 is raised and separated from the side formwork. At this time, after opening all the detachable buckles 36, the two side formwork panels can move freely along the radial linear direction of the track 37. The side formwork panels are separated from the pressure test block 7 by the push-pull plate 38. It should be noted that the inner wall of the groove 332 of the lower formwork 33 is provided with a sealing layer, such as a rubber layer. After the tongue 341 of the upper formwork 34 is inserted, the compression mechanical seal is achieved by the compression of the top formwork 35. At the same time, the compression of the top formwork 35 further tests the sealing performance between the lower formwork 33 and the positioning plate 32.

[0059] like Figure 3 and 9 As shown, the constant load application mechanism 4 is installed on the top beam 23 and includes a telescopic cylinder 41 and a pressure sensor 42. The telescopic cylinder 41 is fixedly installed on the top beam 23 and is a hydraulic cylinder. The output end of the telescopic cylinder 41 is connected to the top template 35 with the pressure sensor 42. In the assembled state, the top template 35 abuts against the symmetrical mechanism to form a closed cavity, and after demolding, it acts as a pressure head to apply constant pressure. The control unit 6 adjusts the telescopic cylinder 41 of the constant load application mechanism 4 according to the feedback from the pressure sensor 42 to maintain constant pressure.

[0060] like Figure 4 and 6 As shown, the elastic compensation base 31 is mounted on the bottom beam 22 and includes a telescopic sleeve 311. An elastic element 312 is provided inside the telescopic sleeve 311 to make the telescopic sleeve 311 elastic. The elastic compensation base 31 is used to keep the pressure test block 7 in contact with the top template 35 at all times, so as to maintain the constant load application mechanism 4 output load to the pressure test block 7.

[0061] like Figure 2 and 7 As shown, the measurement compensation structure 5 includes a mounting base 51, which is anchored to the movable bearing chassis 1. A low-expansion reference rod 52 is anchored to the mounting base 51 and extends freely at its top. The linear expansion coefficient of the low-expansion reference rod 52 is less than that of the pressure-bearing column 21. The displacement acquisition unit 53 is fixed to the top of the reference rod and is used to acquire the axial displacement of the pressure test block 7 relative to the top of the reference rod.

[0062] The low-expansion reference rod 52 can be made of Invar alloy, quartz glass, or carbon fiber composite material. Its extremely low coefficient of expansion ensures that the vertical distance between the top of the reference rod and the anchoring point of the mobile support chassis 1 remains negligible even under drastic temperature fluctuations. The low-expansion reference rod 52 is installed perpendicular to the support surface of the mobile support chassis 1. A protective sleeve 54 is fitted around the low-expansion reference rod 52 but does not contact it. The surface of the protective sleeve 54 has through holes 541. At the construction site, direct sunlight can generate localized high temperatures. The protective sleeve 54 blocks direct heat radiation from the low-expansion reference rod 52, preventing thermal bending caused by temperature differences between the sun-facing and shaded sides. Furthermore, the through holes 541 not only provide ventilation but also create a "chimney effect." External airflow enters the gap through the through holes 541, quickly carrying away the heat absorbed by the protective sleeve 54, ensuring that the temperature inside the protective sleeve 54 remains highly consistent with the outside air temperature, achieving true monitoring under the same conditions.

[0063] The inner wall of the protective sleeve 54 is provided with a low-emissivity coating, and the outer wall of the protective sleeve 54 is provided with a high-reflectivity coating such as a white alumina coating, in order to further reduce the absorption and transmission of heat radiation. The through holes 541 are staggered in the circumference of the protective sleeve 54, so as to form a turbulent flow field to promote the temperature uniformity of the reference rod while blocking direct light from all angles.

[0064] like Figure 2 and 6 As shown, the testing equipment has a measurement configuration state; in the measurement configuration state, the upper template 34 is removed, exposing the top of the pressure test block 7; the top template 35 acts directly on the top surface of the pressure test block 7 as a loading head; the displacement acquisition unit 53 acquires the height displacement data of the pressure test block 7 in a non-contact manner, and the acquired data is uploaded to the control unit 6.

[0065] like Figure 9 As shown, the control unit 6 is electrically connected to a user terminal 8. The user terminal 8 can control the operation of the mobile load-bearing chassis 1, the thermoplastic phase change seal 36, and the constant load application mechanism 4 by sending control commands to the control unit 6.

[0066] This testing equipment can perform synchronous creep testing in the environment where the building is located. By directly casting at the location of the building, it can achieve in-situ casting, in-situ demolding, and in-situ loading. This not only keeps the load application process aligned, but also completely eliminates the internal damage and eccentric compression risks caused by demolding, transportation, and secondary alignment installation in traditional tests to the early-age compression test blocks. It maximizes the restoration of the true state of the building components being formed in one piece and subjected to stress in situ, making the creep data more consistent with the actual condition of the building.

[0067] It should be understood that the specific order or hierarchy of steps in the disclosed process is an example of an exemplary method. Based on design preferences, it should be understood that the specific order or hierarchy of steps in the process may be rearranged without departing from the scope of this disclosure. The appended method claims provide elements of various steps in an exemplary order and are not intended to limit the scope to the specific order or hierarchy described.

[0068] In the detailed description above, various features are combined together in a single embodiment to simplify this disclosure. This approach to disclosure should not be construed as reflecting an intention that embodiments of the claimed subject matter require more features than are explicitly stated in each claim. Rather, as reflected in the appended claims, the invention is presented with fewer features than all of the features in a single disclosed embodiment. Therefore, the appended claims are hereby explicitly incorporated into the detailed description, with each claim representing a separate preferred embodiment of the invention.

[0069] Those skilled in the art will also understand that the various illustrative logic blocks, modules, circuits, and algorithm steps described in conjunction with the embodiments herein can be implemented as electronic hardware, computer software, or a combination thereof. To clearly illustrate the interchangeability between hardware and software, the various illustrative components, blocks, modules, circuits, and steps described above are generally described in terms of their functionality. Whether such functionality is implemented as hardware or software depends on the specific application and the design constraints imposed on the overall system. Those skilled in the art can implement the described functionality in alternative ways for each specific application; however, such implementation decisions should not be construed as departing from the scope of this disclosure.

[0070] The steps of the methods or algorithms described in conjunction with the embodiments herein can be directly embodied in hardware, software modules executed by a processor, or a combination thereof. The software modules can reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disks, removable disks, CD-ROMs, or any other form of storage medium well known in the art. An exemplary storage medium is connected to the processor, enabling the processor to read information from and write information to the storage medium. Of course, the storage medium can also be a component of the processor. The processor and storage medium can reside in an ASIC. The ASIC can reside in a user terminal. Alternatively, the processor and storage medium can exist as discrete components in the user terminal.

[0071] For software implementation, the techniques described in this application can be implemented using modules (e.g., procedures, functions, etc.) that perform the functions described in this application. This software code can be stored in memory units and executed by a processor. The memory units can be implemented within the processor or outside the processor; in the latter case, they are communicatively coupled to the processor via various means, as is well known in the art.

[0072] The foregoing description includes examples of one or more embodiments. It is certainly impossible to describe all possible combinations of components or methods in order to describe the above embodiments, but those skilled in the art will recognize that the various embodiments can be further combined and arranged. Therefore, the embodiments described herein are intended to cover all such changes, modifications, and variations that fall within the scope of the appended claims. Furthermore, the term "comprising" as used in the specification or claims is interpreted in a manner similar to the term "including," as interpreted when used as a conjunction in the claims. Additionally, the use of any term "or" in the specification of the claims is intended to mean "non-exclusive or."

Claims

1. A device for testing the creep characteristics of test blocks under the same conditions based on a test block storage cart, characterized in that, include: Mobile load-bearing chassis, used for free movement and parking on the construction site; The loading gantry frame is installed on a mobile load-bearing chassis and includes a top beam, a bottom beam, and several vertically arranged pressure-bearing columns; The modular casting mold includes two symmetrical halves set on the pressure-bearing column, which are suitable for linear opening and closing to switch between the assembly and demolding states. An elastic compensation base is provided above the bottom beam, which seals and encloses the symmetrical mechanism when assembled. The constant load application mechanism is installed on the top beam, and the output end is connected to the top template with a pressure sensor; In the assembled state, the top template abuts against the symmetrical mechanism to form a closed cavity, and after demolding, it acts as a pressure head to apply constant pressure; The measurement and compensation mechanism includes a low-expansion reference rod with its bottom end anchored to a movable bearing chassis and its top end extending freely. Its coefficient of linear expansion is less than that of the bearing column. The displacement acquisition unit is fixed to the top of the reference rod and is used to acquire the axial displacement of the compressed test block relative to the top of the reference rod. The control unit is used to adjust the output of the constant load application mechanism to maintain constant pressure based on feedback from the pressure sensor, and to calculate creep based on displacement data.

2. The detection device as described in claim 1, characterized in that, The mobile load-bearing chassis includes a chassis body, with active leveling mechanisms located at the four corners of the bottom of the chassis body. The active leveling mechanism includes four independently controlled horizontal adjustment legs and a level sensor located at the center of the chassis body. The control unit is electrically connected to the level sensor and each horizontal adjustment leg, and is used to drive the extension and retraction of each horizontal adjustment leg based on the level data so that the chassis body maintains a level posture.

3. The detection device as described in claim 2, characterized in that, The electric horizontal outrigger includes a pole sleeve fixed to the bottom of the chassis body, with a ball joint cavity at the bottom of the pole sleeve; it also includes a telescopic foot support, the end of the telescopic rod of the telescopic foot support extending into the ball joint cavity and hinged to the pole sleeve via a ball joint; the control unit controls the axial extension and retraction of the telescopic foot support relative to the pole sleeve.

4. The detection device as described in claim 3, characterized in that, The ball joint movable cavity is also provided with a flexible tensioning plate that is laterally tensioned within the ball joint movable cavity, and the telescopic rod of the telescopic foot passes through the central hole of the flexible tensioning plate; the flexible tensioning plate is suitable for limiting the radial swing of the telescopic foot and allowing the telescopic foot to tilt at multiple angles around the ball head.

5. The detection device as described in claim 1, characterized in that, The top edge of the positioning plate is provided with an integrally formed recess. The symmetrical mechanism includes a lower template and an upper template that are interlocked with each other. The bottom of the lower template is provided with a flange that mates with the recess, and the top of the lower template is provided with a groove. The bottom of the upper template is provided with a tongue that mates with the groove. The top of the upper template abuts against the top template to form a closed cavity.

6. The detection device as described in claim 5, characterized in that, The positioning plate recess is provided with a hot-melt phase change seal, which includes an integrated elastic sealing bladder and a heating device. The elastic sealing bladder is filled with phase change wax. The heating device is electrically connected to the control unit and is used to control the phase change wax to melt into a liquid state before the mold is assembled and to stop heating after assembly to allow the phase change wax to solidify and set.

7. The detection device as described in claim 5, characterized in that, The control unit is configured to perform the following sealing steps: upon receiving a mold assembly command, the heating device is activated to heat for a preset time, and after the phase change wax softens, the symmetrical mechanism is driven to close; then the heating is stopped, and the solidified phase change wax is used to fill the micro-assembly gap between the lower template and the positioning plate.

8. The detection device as described in claim 5, characterized in that, The pressure-bearing column is equipped with a track, and a push-pull plate is slidably mounted on the track. The push-pull plate is connected to the lower template and is suitable for driving the lower and upper templates of the symmetrical mechanism to open and close radially.

9. The detection device as described in claim 5, characterized in that, The upper and lower templates are equipped with detachable buckles. When the detachable buckles are unlocked, the symmetrical mechanism can move freely and linearly along the track. After assembly, the movement of the symmetrical mechanism can be restricted by locking the detachable buckles.

10. The detection device as described in claim 5, characterized in that, The testing equipment has a measurement configuration state; in the measurement configuration state, the upper template is removed, exposing the top of the pressure test block; the top template acts directly on the top surface of the pressure test block as a loading head; the displacement acquisition unit collects the height displacement data of the pressure test block in a non-contact manner.

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