A Z-shaped steel beam type compression and uplift integrated test device

Abstract

The utility model relates to the technical field of foundation engineering detection, concretely to a few character type steel roof beam formula compression resistance and pull -out integrated test device, aims at solving the problem of traditional test device single function, equipment utilization rate is low, and the system stability is poor when testing under high pile head scene, and there is the problem of overturning risk. Its technical scheme main points are: adopt the modularization few character type counterforce frame unit as the core bearing structure, and the upper crossbeam, telescopic longitudinal beam and lower crossbeam form the stable frame, through the load application mode switching, the hydraulic jack is placed between the pile top and the upper crossbeam when the compression test, then the jack is installed on the upper crossbeam top when the pull -out test, and the piston rod acts on the upper stress plate connected with the pile top through the screw rod, realizes one set of device to complete two kinds of tests. The present application is mainly used for the vertical bearing capacity field detection of high pile head photovoltaic pile and other pile foundation.

Description

Technical Field

[0001] This utility model relates to the technical field of foundation testing for photovoltaic projects, and in particular to a Z-shaped steel beam integrated compressive and tensile testing device. Background Technology

[0002] In the construction of photovoltaic power stations, some mountainous, water-based, or agro-photovoltaic complementary projects require the photovoltaic support piles to be designed with the pile heads 2 meters or even higher above the ground for reasons such as terrain adaptation, crop planting space, or flood control. For such high-pile-head foundations, on-site testing of their vertical (compressive and tensile) bearing capacity is a major technical challenge.

[0003] Currently, traditional surcharge testing equipment faces significant drawbacks in such scenarios: First, its reaction platform needs to be built on the ground, and in high pile head scenarios, the platform has a high center of gravity and poor stability, posing a significant risk of overturning; Second, the transportation and hoisting of a large number of counterweights and the requirement for site flatness are high, resulting in low efficiency and high cost; Finally, compression tests and pull-out tests usually require two independent loading and reaction systems, leading to low equipment utilization, long testing cycles, and high overall costs.

[0004] Therefore, there is an urgent need for an integrated testing device that is easy to install, stable and reliable, and compatible with both compressive and tensile tests, specifically designed for high pile head scenarios. Utility Model Content

[0005] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a Z-shaped steel beam integrated compressive and tensile testing device. This device, through its modularly designed Z-shaped reaction frame and adjustable support legs, adapts to different pile head heights, utilizes counterweight loading to provide stable reaction force, and through the flexible configuration of the load application system, efficiently and safely completes vertical compressive and tensile bearing capacity tests on the same main structure.

[0006] The technical solution adopted by this utility model to solve its technical problem is: a Z-shaped steel beam integrated compressive and tensile testing device, comprising:

[0007] At least one modular Z-shaped reaction frame unit, the Z-shaped reaction frame unit includes an upper crossbeam, four telescopic longitudinal beams distributed in a matrix at the bottom of the upper crossbeam, and four lower crossbeams horizontally connected to the bottom ends of the four telescopic longitudinal beams respectively, the four lower crossbeams being used to support the counterweight.

[0008] The load application system is used to apply vertical loads to the pile to be tested; the load application system includes hydraulic jacks and pull-out anchors;

[0009] The pile to be tested is located below the Z-shaped reaction frame unit;

[0010] When conducting the compression test, the hydraulic jack is placed directly between the top of the pile to be tested and the upper crossbeam.

[0011] When conducting a pull-out test, the pull-out anchor includes a lower load-bearing plate installed on the top of the pile to be tested, an upper load-bearing plate located above the upper crossbeam, and a screw connecting the upper load-bearing plate and the lower load-bearing plate; a hydraulic jack is installed and fixed on the top of the upper crossbeam, with the extended end of its piston rod pointing upward and acting in conjunction with the upper load-bearing plate; the screw passes through both sides of the upper crossbeam.

[0012] To provide a simple, direct, and easily adjustable anchoring connection method for effectively transferring the pull-out force of the pile under test to the upper reaction frame beam, this invention further specifies that the anchoring assembly includes a vertically arranged screw rod. The lower end of the screw rod is anchored inside the pile under test, and the upper end passes through a through hole in the upper beam and connects to the load-bearing connecting plate. This achieves a stable and quantifiable transfer of pull-out force from the pile body to the upper beam, and the threaded connection of the screw rod provides convenient length fine-tuning and pre-tightening functions, improving the convenience and reliability of pull-out test installation.

[0013] To facilitate height adjustment of the reaction frame to accommodate different pile lengths exposed above ground and enhance the overall stability of the device within the photovoltaic array, this invention further specifies that the telescopic longitudinal beam includes an outer sleeve and an inner telescopic rod that extends and retracts hydraulically. The bottom or side of the telescopic longitudinal beam is equipped with connectors for linking with adjacent photovoltaic piles. Hydraulic drive enables rapid and precise adjustment of the longitudinal beam height, expanding the applicable pile length range of the device. The lateral connectors link the test device to surrounding engineering structures, effectively preventing overturning or displacement during loading and improving the safety of field tests.

[0014] To prevent localized deformation, stress concentration, or slippage at the contact point between the hydraulic jack and the upper crossbeam during the compression test, this invention further specifies that the lower surface of the upper crossbeam is equipped with a reinforcing pad or anti-slip limiting structure for the lifting position of the hydraulic jack. This strengthens the rigidity and compressive strength of the key stress-bearing parts of the upper crossbeam, ensures the uniform and stable transmission of the jack's lifting reaction force, improves the accuracy of test data, and extends the service life of the upper crossbeam.

[0015] To enable flexible combination of individual reaction frame units to meet the needs of testing pile foundations with different spacings (especially multi-pile or large-span cases), this invention further specifies that multiple Z-shaped reaction frame units are spliced ​​along the length of the upper crossbeam to expand the bearing span. This achieves on-demand expansion of the device's bearing span, greatly improving the versatility and site adaptability of the testing device, enabling it to be applied economically and efficiently to various complex pile foundation testing scenarios.

[0016] To prevent the counterweight supported on the lower crossbeam from accidentally slipping off during testing or due to external influences, this invention further specifies that a stop is provided on the lower crossbeam to prevent the counterweight from slipping off. This provides effective lateral restraint for the counterweight, significantly improving the stability and operational safety when stacking counterweights, and reducing the risk of safety accidents caused by counterweight slippage.

[0017] The beneficial effects of this utility model are:

[0018] I. By using a device with a Z-shaped reaction frame as its core, the hydraulic jacks can be continuously tested for compression and pull-out by simply switching their installation position and operating mode (placed on the top of the pile or installed on the top of the upper crossbeam). This achieves one-time setup and two-time testing, greatly improving equipment utilization, reducing the number of equipment transfers and hoistings, lowering testing costs and cycles, and effectively solving the problem of vertical bearing capacity testing for high-pile photovoltaic piles.

[0019] Second, the device adopts a unique Z-shaped three-dimensional frame structure, which has better overall rigidity and torsional performance than traditional I-beams; the support legs can be hydraulically extended and retracted to adapt to different pile heights, combined with the low center of gravity counterweight design, and can be further enhanced by connecting with adjacent photovoltaic piles. Thus, together with the reliable pull-out anchoring system composed of upper and lower force plates and screws, it significantly enhances the overall stability of the reaction system, effectively eliminates the risk of overturning in high pile head testing, and ensures operational safety and the accuracy of test data;

[0020] 3. The Z-shaped reaction frame unit adopts a modular design and can be flexibly spliced; the height of the support legs is adjustable, enabling the device to adapt to test scenarios with different pile head heights of 3-6 meters, various site conditions and bearing capacity requirements, and has strong versatility; this design simplifies the installation process, reduces the cost of counterweight transportation and hoisting, and improves testing efficiency.

[0021] Fourth, the installation process of the device is standardized. During the pull-out test, the load is lifted upwards by the jack installed on the top of the upper crossbeam to the upper load plate, and then transmitted to the top of the pile through the screw assembly. It is then balanced by the counterweight concentrated on the lower crossbeam platform. The force transmission path is clear and direct. The entire rigid reaction system has small deformation, thus ensuring the accuracy and reliability of the test data. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of this utility model. Figure 1 ;

[0023] Figure 2 This is a schematic diagram of the structure of this utility model. Figure 2 .

[0024] The labels in the diagram are: 1. Upper crossbeam; 2. Telescopic longitudinal beam; 3. Lower crossbeam; 4. Counterweight; 5. Stake to be tested; 6. Hydraulic jack; 7. Pull-out anchor. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0026] See Figure 1 and Figure 2 This utility model discloses a U-shaped steel beam integrated compressive and tensile testing device, which is a single pile vertical bearing capacity testing device for scenarios where the pile head is more than 2 meters above the ground. It is particularly suitable for integrated on-site testing of compressive and tensile strength in high-pile photovoltaic projects. This device uses a modular U-shaped steel beam reaction frame as the core bearing component and achieves the integrated function of one-time setup and two tests through a switchable load application system.

[0027] The Z-shaped reaction frame unit is the main load-bearing and counterweight-bearing structure of the device. This unit is composed of modular Z-shaped steel beams made of high-strength steel. A single steel beam section can be 5 meters long, and its three-dimensional frame has a cross-sectional dimension of 300mm high × 400mm wide × 12mm web thickness. Vertical support steel plates can be added internally at 20mm intervals to enhance local rigidity. This unique Z-shaped three-dimensional frame structure increases the overall bending stiffness by approximately 40% compared to traditional I-beams, exhibiting superior mechanical properties.

[0028] Each U-shaped reaction frame unit consists of an upper crossbeam 1, four matrix-distributed telescopic longitudinal beams 2, and four lower crossbeams 3, welded or connected by high-strength bolts to form a stable three-dimensional frame. The upper crossbeam 1, as the core reaction component, has reinforcing pads welded to its lower surface at positions corresponding to the hydraulic jacks 6, or grooves with positioning functions, forming a reaction seat to disperse concentrated stress and prevent jack slippage during loading. The lower crossbeams 3 together form a wide, low, and stable load-bearing platform or base, with an anti-slip limiting plate at its top, specifically designed for the orderly and stable placement of standardized concrete counterweights 4. Each standard counterweight weighs 2 tons and effectively prevents accidental slippage. When the required reaction force is large and a single U-shaped reaction frame unit and its counterweight cannot meet the demand, multiple U-shaped reaction frame units can be longitudinally spliced ​​along the length of the upper crossbeam 1 using end connecting plates to expand the overall span and support more counterweight.

[0029] The telescopic longitudinal beam 2 is a key component of the support system, symmetrically and stably distributed beneath the entire frame. Each telescopic longitudinal beam 2 is hydraulically driven for telescoping and consists of an outer sleeve and an inner telescopic rod fitted inside it, with an adjustment range of 1.5-3 meters. This allows the working platform height of the entire U-shaped reaction frame unit to flexibly adapt to different testing scenarios where the pile head is 3-6 meters above the ground. A base plate can be installed at the bottom of the telescopic longitudinal beam 2 to increase the ground contact area. To significantly enhance the system's stability under high-altitude loads and completely eliminate the risk of overturning, connecting lugs can be installed on the sides of the telescopic longitudinal beam 2. These lugs can be rigidly connected to adjacent installed photovoltaic piles via steel wire ropes or tie rods, thus forming a spatial triangular stable system together with the reaction frame and the ground. In addition, the device can be used in conjunction with anti-fall-off baffles and tilt warning systems to monitor the operating status in real time and provide safety protection.

[0030] The load application system is used to apply precise vertical loads to the pile 5 under test and to quickly switch between compressive and tensile functions. The system mainly includes hydraulic jacks 6 and dedicated tensile anchors 7. The hydraulic jacks 6 are driven by an electric hydraulic pump station and can perform precise graded loading and pressure stabilization.

[0031] The specific working process of this utility model is as follows:

[0032] Device Assembly: Based on the pile head height of the pile 5 to be tested, synchronously adjust the inner telescopic rods of the four telescopic longitudinal beams 2 to the required length and lock them. Hoist the assembled Z-shaped reaction frame unit to the top of the telescopic longitudinal beams 2 and fix it, ensuring that the pile 5 to be tested is directly below it. Symmetrically and stably stack standard counterweights 4 of sufficient weight on the platform formed by the lower crossbeams 3. The telescopic longitudinal beams 2 can be connected to adjacent piles via connectors to form a stable triangular support system.

[0033] Conduct the compression test: Place the hydraulic jack 6 directly between the top of the pile 5 to be tested and the upper crossbeam 1. Adjust the position of the hydraulic jack 6 to align it. Start the hydraulic pump station; the hydraulic jack 6 will lift the upper crossbeam 1 upwards. The reaction force is balanced by the gravity of the counterweight 4, thus achieving gradual downward pressure on the pile body.

[0034] Switch to pull-out test: After the compression test is completed, remove the hydraulic jack 6 from the top of the pile. Install the pull-out anchor 7, specifically: fix the lower load-bearing plate on top of the pile 5 to be tested, place the upper load-bearing plate above the upper crossbeam 1, and connect the upper and lower load-bearing plates with screws, which pass through both sides of the upper crossbeam 1. At this time, install and fix the hydraulic jack 6 on top of the upper crossbeam 1, with its piston rod extending upward and interacting with the upper load-bearing plate. Start the hydraulic pump station, and the piston rod of the hydraulic jack 6 extends upward, pushing the upper load-bearing plate and the screw connected to it, thereby applying an upward tensile force to the pile body to achieve pull-out loading. In this mode, the upward pull-out force is transmitted to the upper crossbeam 1 through the screw and is finally balanced by the counterweight system.

[0035] This invention, through its integrated design, is compatible with both compressive and tensile tests, eliminating the need to replace the core reaction equipment and increasing equipment utilization by over 50%, significantly reducing testing costs. Its modular and adjustable design simplifies the installation process, reduces requirements for site flatness, and simplifies the transportation and hoisting of counterweights, thereby improving testing efficiency. More importantly, the combination of the Z-shaped steel beams with a triangular stabilization system and safety warning significantly enhances the stability and rigidity of the reaction system, ensuring the accuracy of test data and completely eliminating the overturning risk in high pile head testing, perfectly meeting the efficient and safe construction requirements of photovoltaic projects.

[0036] The above are merely preferred embodiments of this utility model, but the scope of protection of this utility model is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in this utility model, based on the technical solution and inventive concept of this utility model, should be included within the scope of protection of this utility model.

Claims

1. A Z-shaped steel beam integrated compressive and tensile testing device, characterized in that, include: At least one modular Z-shaped reaction frame unit, the Z-shaped reaction frame unit includes an upper crossbeam (1), four telescopic longitudinal beams (2) distributed in a matrix at the bottom of the upper crossbeam (1), and four lower crossbeams (3) respectively horizontally connected to the bottom ends of the four telescopic longitudinal beams (2), the four lower crossbeams (3) being used to support the counterweight (4). A load application system is used to apply a vertical load to the pile (5) to be tested; the load application system includes a hydraulic jack (6) and an anti-pull-out anchor (7). The pile to be tested (5) is located below the zigzag reaction frame unit; When the compression test is carried out, the hydraulic jack (6) is placed directly between the top of the pile to be tested (5) and the upper crossbeam (1); When a pull-out test is performed, the pull-out anchor (7) includes a lower force plate installed on the top of the pile (5) to be tested, an upper force plate located above the upper crossbeam (1), and a screw connecting the upper force plate and the lower force plate; the hydraulic jack (6) is installed and fixed on the top of the upper crossbeam (1), with the extended end of its piston rod facing upward and acting on the upper force plate; the screw passes through both sides of the upper crossbeam (1).

2. The integrated compressive and tensile testing device of a U-shaped steel beam as described in claim 1, characterized in that, The pull-out anchor (7) includes a vertically arranged screw rod. The lower end of the screw rod is anchored in the pile to be tested (5), and the upper end passes through the through hole opened on the upper crossbeam (1) and is connected to the upper load-bearing plate.

3. The integrated compressive and tensile testing device for a U-shaped steel beam as described in claim 1, characterized in that, The telescopic longitudinal beam (2) includes an outer sleeve and an inner telescopic rod that is hydraulically driven to extend and retract. The bottom or side of the telescopic longitudinal beam (2) is provided with a connector for connecting with an adjacent photovoltaic pile.

4. The integrated compressive and tensile testing device for a U-shaped steel beam as described in claim 1, characterized in that, The lower surface of the upper beam (1) is provided with a reinforcing pad or anti-slip limiting structure for the lifting position of the hydraulic jack (6).

5. The integrated compressive and tensile testing device for a U-shaped steel beam as described in claim 1, characterized in that, Multiple of the above-mentioned zigzag reaction frame units are spliced ​​along the length direction of the upper crossbeam (1) to extend the load-bearing span.

6. The integrated compressive and tensile testing device of a U-shaped steel beam as described in claim 1, characterized in that, The lower crossbeam (3) is provided with a stop to prevent the counterweight (4) from slipping.

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