Improved concrete creep meter

Abstract

This invention discloses an improved concrete creep meter, belonging to the field of building surveying technology. It includes a test frame with a pressure mechanism at the top. An upper pressure plate and a lower pressure plate are located within the test frame, with the pressure mechanism fixed to the upper pressure plate. Concrete specimens are symmetrically placed between the upper and lower pressure plates. The pressure mechanism is positioned above the concrete specimens, and a centering block is placed between two concrete specimens. Deformation testing frames are located on the outer sides of the concrete specimens. Telescopic connecting mechanisms are detachably connected to the four corners of the centering block, passing through the deformation testing frames. This invention, through its "assisted positioning followed by rapid disassembly" design, effectively eliminates the physical constraint of the deformation testing frames on the gauge length of the concrete specimens after fixation, avoiding mechanical interference from external components on the measurement area, thus fundamentally ensuring the authenticity and accuracy of creep deformation data.

Description

Technical Field

[0001] This invention belongs to the field of building surveying technology, and in particular relates to an improved concrete creep meter. Background Technology

[0002] Currently, concrete creep tests consist of two parts: specimen loading and data recording. Specimen loading is generally performed using a creep meter, while data recording can be done using a dial gauge to record deformation or by detecting strain through an intelligent data acquisition system.

[0003] Existing concrete creep loading devices (i.e., creep meters) have the following problems: (1) Each set of concrete specimens is made up of short columns stacked together. The manual alignment between the short columns often produces a non-negligible deviation, which causes the beam ends of the specimens to be eccentrically compressed or even to be in tension at one end and compressed at the other. This is very unfavorable when combined with the characteristics of concrete specimens that have strong compressive strength but weak tensile strength.

[0004] (2) If a dial indicator is used to measure the creep deformation value, manually adjusting the position of the measuring frame will also produce a certain amount of deviation. Summary of the Invention

[0005] The purpose of this invention is to provide an improved concrete creep meter to solve the problems existing in the prior art.

[0006] To achieve the above objectives, the present invention provides the following solution: The present invention provides an improved concrete creep apparatus, comprising a test frame, a pressure mechanism at the top of the test frame, an upper pressure plate and a lower pressure plate respectively within the test frame, the pressure mechanism being fixedly connected to the upper pressure plate, concrete specimens symmetrically arranged between the upper pressure plate and the lower pressure plate, the pressure mechanism being located above the concrete specimens, a centering block being provided between two concrete specimens, and a deformation test outer frame being provided on the outer side of each concrete specimen, with telescopic connecting mechanisms detachably connected to the four corners of the centering block, the telescopic connecting mechanisms passing through the deformation test outer frame.

[0007] Optionally, the centering pad has limiting protrusions at the top and bottom, and the concrete specimen has reserved holes at both ends, which are adapted to the limiting protrusions adjacent to them.

[0008] Optionally, the centering pad is provided with a first slot at each of its four corners, and the first slot is adapted to the telescopic connection mechanism.

[0009] Optionally, the pressurizing mechanism includes a hydraulic jack fixed to the upper pressure plate, and the hydraulic jack is equipped with a force sensor.

[0010] Optionally, the test frame includes multiple high-strength screws, the upper pressure plate and the lower pressure plate are slidably connected to the high-strength screws respectively, the top surface of the lower pressure plate is provided with a ball joint, the top surface of the ball joint is equipped with a disc-shaped gasket, and the top of the disc-shaped gasket is provided with the concrete specimen.

[0011] Optionally, the test frame is provided with an upper top plate and a lower bottom plate, and a spring is provided between the lower bottom plate and the lower pressure plate.

[0012] Optionally, the telescopic connection mechanism includes a telescopic rod with a spring buckle inside. The telescopic rod is adapted to the first slot, passes through the deformation test frame, and its top is adapted to the hydraulic jack, while its bottom is adapted to the disc-shaped pad.

[0013] Optionally, the high-strength screw is provided with a plurality of high-strength bolts, which are respectively adapted to the upper top plate, the lower bottom plate and the upper pressure plate.

[0014] The present invention discloses the following technical effects: Through the design of "first assisting positioning and then rapid disassembly", the present invention effectively eliminates the physical constraint on the gauge section of the concrete specimen (i.e. the key benchmark section for post-processing creep deformation data) after the outer frame of the deformation test is fixed, avoids the mechanical interference of external components on the measurement area, and thus fundamentally ensures the authenticity and accuracy of the creep deformation data. Attached Figure Description

[0015] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The embodiments of this application and their descriptions are used to explain this application and do not constitute an undue limitation of this application. In the drawings: Figure 1 This is a schematic diagram of the structure of the improved concrete creep meter of the present invention; Figure 2 This is a top view of the centering pad block of the present invention; Figure 3 This is a front view of the centering pad block of the present invention; Figure 4 This is a schematic diagram of the telescopic connection mechanism of the present invention.

[0016] Figure label: 1. Hydraulic jack; 2. Force sensor; 3. Centering pad; 4. Disc-type shim; 5. Lower pressure plate; 6. High-strength screw; 7. High-strength bolt; 8. Upper pressure plate; 9. Deformation test frame; 10. Telescopic connection mechanism; 11. Ball joint; 12. Spring; 13. Telescopic rod; 14. Spring clip. Detailed Implementation

[0017] 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.

[0018] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0019] Reference Figures 1 to 4 As shown, this embodiment provides an improved concrete creep meter with a more rational structural design and higher measurement accuracy. The device comprises a stable test frame, with a pressure mechanism for applying loads located at the top inside the frame. Simultaneously, an upper pressure plate 8 and a lower pressure plate 5 are arranged sequentially from top to bottom inside the test frame, with the pressure mechanism rigidly connected to the upper pressure plate 8 for secure fixation. Two concrete specimens are symmetrically arranged in the space between the upper pressure plate 8 and the lower pressure plate 5, with the pressure mechanism positioned directly above these two specimens to ensure that pressure is transmitted vertically and uniformly to the specimens. To ensure good coaxial alignment of the two concrete specimens during loading, a specially designed centering block 3 is placed between them. Furthermore, a deformation test frame 9 for monitoring deformation is installed on the outer side of each concrete specimen. Specifically, each of the four corners of the centering block 3 has a detachable connection structure, which is connected to a set of telescopic connection mechanisms 10. These telescopic connection mechanisms 10 can pass through the corresponding deformation test frame 9, thus providing auxiliary positioning during the initial installation phase.

[0020] The specific operating procedure is as follows: First, the entire test frame needs to be horizontally adjusted to ensure that both the upper pressure plate 8 and the lower pressure plate 5 are strictly parallel to the ground, laying the foundation for subsequent precise loading; second, the two concrete specimens are stacked and assembled, and using the improved centering block 3 proposed in this invention, the pre-reserved holes at the bottom are precisely aligned and directly inserted into the protruding limiting structure at the top of the centering block 3. After completing the initial centering, the stacked concrete specimens are then securely installed into the test frame; next, four sets of telescopic connection mechanisms 10 are installed around the centering block 3, and then the deformed... The outer frame 9 is directly fitted onto the ends of the four telescopic connecting mechanisms 10 from above. Then, precision measuring instruments such as dial gauges are installed and fixed on the deformation test frame 9 to record the deformation data of the concrete specimen under long-term load in real time. After the measurement system is installed, the telescopic connecting mechanisms 10 around the perimeter can be removed one by one. Finally, the pressurization mechanism is activated to apply the set creep stress to the concrete specimen and the upper pressure plate 8 is locked to maintain a constant load state during subsequent long-term observation, thereby systematically observing and recording the changes in the long-term shrinkage and creep properties of concrete materials under continuous stress.

[0021] The core innovation of this invention lies in its ingenious design concept of "assisted positioning followed by rapid disassembly." This design effectively solves the problem in traditional creep meters where the outer frame of the deformation test exerts unnecessary physical constraints on the gauge length of the concrete specimen (i.e., the key benchmark measurement section relied upon for subsequent processing of creep deformation data). It completely avoids mechanical interference or additional stress on the gauge length area caused by external fixing components, thereby fundamentally ensuring the authenticity, reliability, and high accuracy of the collected creep deformation data, and significantly improving the scientific value and engineering reference significance of the test results.

[0022] To further improve the alignment accuracy and ease of operation of the device, this solution also proposes several optimized designs. For example, limiting protrusions are set at the top and bottom of the alignment pad 3, while the corresponding concrete specimens have pre-cast matching reserved holes at both ends. During installation, simply align the reserved holes of the concrete specimens accurately and directly fit them onto the limiting protrusions on the alignment pad 3 to achieve precise alignment in one step. This structure, used in conjunction with pre-fabricated perforated concrete specimens, not only greatly simplifies the tedious process of manual alignment adjustment but also effectively prevents eccentric compression caused by initial installation eccentricity during long-term load bearing, thereby avoiding the problems of concrete creep performance degradation or service life reduction caused by this.

[0023] In addition, first slots are provided at the four corners of the centering block 3. The geometry and size of these slots are adapted to the connection end of the telescopic connection mechanism 10, ensuring that the two can be quickly and securely engaged. Regarding the pressurization mechanism, it specifically includes a hydraulic jack 1 fixed to the upper pressure plate 8. This jack integrates a force sensor 2, which can monitor and provide feedback on the actual load applied to the concrete specimen in real time during loading, thereby achieving precise and controllable pressure application.

[0024] Regarding the overall structure of the test frame, it mainly consists of a main support system composed of multiple high-strength screws 6. The upper pressure plate 8 and the lower pressure plate 5 are assembled with these high-strength screws 6 by sliding connection to accommodate small displacements during loading. In particular, a ball joint 11 is provided on the top surface of the lower pressure plate 5, and a disc-shaped gasket 4 is installed on the upper surface of the ball joint 11. The concrete specimen is placed on top of the disc-shaped gasket 4. This design helps to automatically level and evenly distribute the reaction force, further improving the coaxiality of the loading. In addition, the test frame also has an upper top plate and a lower bottom plate. A spring 12 is arranged between the lower bottom plate and the lower pressure plate 5 to buffer the initial loading impact and improve the system stability.

[0025] Regarding the specific construction of the telescopic connection mechanism 10, it mainly includes a telescopic and adjustable telescopic rod 13. The telescopic rod 13 integrates a spring clip 14, which allows the telescopic rod 13 to be quickly plugged into and pulled into the first slot on the centering pad 3. The external dimensions of the telescopic rod 13 precisely match the first slot, and its length extends through the deformation test frame 9. Its top end can form a temporary support with the bottom of the hydraulic jack 1, while its bottom is adapted to the disc-shaped pad 4, thus forming a stable temporary positioning support system during the installation phase.

[0026] During actual installation, after the concrete composite specimen and the centering pad 3 are in place, the operator can evenly insert four telescopic connecting mechanisms 10 of the same length around the centering pad 3. Then, the deformation test frame 9 is fitted onto the upper end of these four telescopic connecting mechanisms 10. At this time, with the help of the fine-tuning telescopic function of the telescopic connecting mechanism 10, the operator can flexibly adjust the horizontal position of the deformation test frame 9 relative to the lower pad, achieving rapid alignment and high-precision centering. Once the position of the deformation test frame 9 is completely determined and firmly fixed, simply press the spring clip 14 in the middle of the telescopic rod 13 to easily and quickly remove the entire telescopic connecting mechanism 10 from the system, leaving no residual constraints.

[0027] In summary, this invention, through its integrated design strategy of "assisted positioning followed by rapid disassembly," not only significantly improves the installation efficiency and alignment accuracy of concrete creep tests, but more importantly, it completely eliminates the physical constraints caused by fixed structures on gauge sections in traditional methods. This fundamentally prevents mechanical interference from external components on key measurement areas, thereby ensuring the high authenticity and accuracy of creep deformation data. To further enhance the adjustability and stability of the overall structure, multiple high-strength bolts 7 are also configured on the high-strength screw 6. These bolts form reliable connections with the upper top plate, lower bottom plate, and upper pressure plate 8, respectively, enabling the entire test frame to maintain excellent structural stiffness and geometric stability under long-term loads.

[0028] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0029] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. An improved concrete creep meter, characterized in that: The test includes a test frame, with a pressure mechanism at the top inside the test frame. An upper pressure plate (8) and a lower pressure plate (5) are respectively provided inside the test frame. The pressure mechanism is fixedly connected to the upper pressure plate (8). Concrete specimens are symmetrically arranged between the upper pressure plate (8) and the lower pressure plate (5). The pressure mechanism is located above the concrete specimens. A centering block (3) is provided between the two concrete specimens. A deformation test frame (9) is provided on the outside of the concrete specimens. Telescopic connection mechanisms (10) are detachably connected to the four corners of the centering block (3). The telescopic connection mechanism (10) passes through the deformation test frame (9).

2. The improved concrete creep meter according to claim 1, characterized in that: The centering pad (3) is provided with limiting protrusions at the top and bottom, and the concrete specimen is provided with reserved holes at both ends. The reserved holes are adapted to the limiting protrusions adjacent to them.

3. The improved concrete creep meter according to claim 1, characterized in that: The centering pad (3) has a first slot at each of its four corners, and the first slot is adapted to the telescopic connecting mechanism (10).

4. The improved concrete creep meter according to claim 3, characterized in that: The pressurizing mechanism includes a hydraulic jack (1) fixed to the upper pressure plate (8), and a force sensor (2) is provided inside the hydraulic jack (1).

5. The improved concrete creep meter according to claim 4, characterized in that: The test frame includes multiple high-strength screws (6), the upper pressure plate (8) and the lower pressure plate (5) are slidably connected to the high-strength screws (6), the top surface of the lower pressure plate (5) is provided with a ball joint (11), the top surface of the ball joint (11) is equipped with a disc-type gasket (4), and the top of the disc-type gasket (4) is provided with the concrete specimen.

6. The improved concrete creep meter according to claim 5, characterized in that: The test frame is provided with an upper top plate and a lower bottom plate, and a spring (12) is provided between the lower bottom plate and the lower pressure plate (5).

7. The improved concrete creep meter according to claim 5, characterized in that: The telescopic connection mechanism (10) includes a telescopic rod (13), which is provided with a spring buckle (14). The telescopic rod (13) is adapted to the first slot. The telescopic rod (13) passes through the deformation test frame (9). The top of the telescopic rod (13) is adapted to the hydraulic jack (1), and the bottom of the telescopic rod (13) is adapted to the disc-shaped gasket.

8. The improved concrete creep meter according to claim 6, characterized in that: The high-strength screw (6) is provided with a plurality of high-strength bolts (7), which are respectively adapted to the upper top plate, the lower bottom plate and the upper pressure plate (8).

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