A system and method for loading test of an arch bridge model

Abstract

The present application relates to the technical field of arch bridge, and particularly relates to a loading test system for arch bridge model, which comprises a servo actuator, a control system and a plurality of interval arranged bearing counterforce frames, the plurality of bearing counterforce frames are connected through a continuous beam, at least one of the servo actuators is a static servo actuator and at least one is a dynamic servo actuator, the bearing counterforce frame is installed with a frame cross beam and an arc loading beam, the arc loading beam is fixedly connected below the frame cross beam, the bottom surface of the arc loading beam is an arc surface, the frame cross beam can drive the arc loading beam to automatically lift, the arc loading beam and the continuous beam are all installed with a plurality of servo actuators, and the control system is used for controlling the servo actuators. The arc loading beam of the present application is attached to the top of the arch bridge, the servo actuator installed on the arc loading beam has a plurality of loading directions (usually 0-180 degrees), so that the simulation loading of the multi-point and multi-direction load of the large scale bridge model can be realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of arch bridges, and in particular to a system and method for loading test of an arch bridge model. BACKGROUND

[0002] Super-long-span arch bridges (span of 600 and above) have broad application prospects in high-speed railway construction. With the increase of span, the design of arch bridges is difficult, the stress level of key components is high, the bridge span structure system is constantly transformed during construction, the arch rib segment hoisting tonnage is large, the stress state of key components and nodes is very complex, and sudden catastrophic loads may occur during construction. The stability of the construction process is outstanding. In order to fully understand the safety state of key components during the whole construction process, it is necessary to carry out stress state simulation test of large-scale components, analyze the strength and stability of key components, and then guide the optimization and improvement of design and construction method of super-long-span arch bridges.

[0003] The commonly used method for overall loading of arch bridges at present is to simulate arch bridge load by adding weights. This method has high requirements for manpower and material resources, and the loading weight is not accurate. It is time-consuming and laborious, cannot apply load at any position, and cannot accurately simulate the load conditions in actual engineering. For K-shaped nodes and cross-shaped nodes of arch bridges, the current mechanical loading device can only apply load to a small range of angles of K-shaped nodes, and cannot perform K-shaped node tests at any angle. The current experimental equipment includes the "high-speed railway foundation dynamic simulation test system" of Zhejiang University, the "high-pile wharf dynamic loading test system" of Chongqing Jiaotong University, and the "three-direction mobile static loading system" of the River and Ocean University. None of the three loading systems can perform multi-point and multi-direction loading, and cannot provide relatively complete test loading in arch bridge tests.

[0004] In summary of the current technology, there is no more convenient method for overall load application of arch bridge models, and the same problem exists in the loading of K-shaped nodes and cross-shaped nodes. The current technical means seriously affects the development of arch bridges. SUMMARY

[0005] The present application aims to solve the problem that existing arch bridges cannot complete multi-point and multi-direction loading of structures and cannot perform arbitrary angle loading of K-shaped nodes, and provides a system and method for loading test of an arch bridge model.

[0006] To achieve the above-mentioned purpose, the technical scheme adopted by the present application is as follows:

[0007] The utility model provides an arch bridge model loading test system, including servo actuator, control system and a plurality of interval arrangement's bearing counterforce frame, a plurality of bearing counterforce frame is connected through continuous beam, at least one of servo actuator is static servo actuator and at least one is dynamic servo actuator, bearing counterforce frame is installed with frame crossbeam and arc loading beam, arc loading beam is fixedly connected below frame crossbeam, the bottom of arc loading beam is arc surface, frame crossbeam can drive arc loading beam automatic lifting, arc loading beam, continuous beam all are installed with a plurality of servo actuator, control system is used for controlling servo actuator.

[0008] The static servo actuator (static force loading) of the utility model can simulate the bearing capacity of the bridge under short-term load effect, and the dynamic servo actuator (dynamic force loading) can simulate the earthquake effect. The servo actuator installed on the continuous beam can provide vertical load simulation of vehicle load in the operation stage for the arch bridge, and can test and research the bearing capacity and overall stability of the arch bridge. The arc loading beam is attached to the top of the arch bridge, the servo actuator installed on the arc loading beam has multiple loading directions (usually 0-180 degrees), and can apply multiple angle dynamic loads to the arch bridge, so that the simulation loading of multiple point and multi-direction loads of the large-scale bridge model can be realized.

[0009] As a preferred scheme of the utility model, the bottom of the arc loading beam is provided with a plurality of actuator connecting plates for connecting the servo actuators.

[0010] As a preferred scheme of the utility model, the central angle of the arc loading beam is greater than 90 degrees and less than or equal to 180 degrees.

[0011] As a preferred scheme of the utility model, the working platform at the bottom of the bearing counterforce frame is further provided with a horizontal beam, and the horizontal beam is connected with a jack for fixing the K-shaped node and loading.

[0012] As a preferred scheme of the utility model, the inside of the bearing counterforce frame is further provided with a horizontal loading beam, and the servo actuator is installed on the horizontal loading beam. The servo actuator installed on the horizontal loading beam is used for horizontal loading. The servo actuator installed on the horizontal loading beam is used for horizontal loading, which can simulate the bearing capacity of the bridge under horizontal load (such as wind load), so that the simulation loading of vertical train load and horizontal wind load can be completed at the same time.

[0013] As a preferred scheme of the utility model, the horizontal loading beam includes a horizontal loading longitudinal beam and a horizontal loading transverse beam connected with each other.

[0014] As a preferred scheme of the present application, the load cross beam is connected between the load bearing counterforce frames, and the servo actuator is installed on the load cross beam.

[0015] As a preferred scheme of the present application, the continuous beam and the load cross beam are both horizontally arranged, and are both connected with at least two servo actuators, and the installation position of the servo actuators is adjustable, so as to facilitate the adjustment of the loading position.

[0016] As a preferred scheme of the present application, the control system comprises a plurality of control channels, each of which is equipped with two closed-loop control loops of test force and displacement, and the control system can control the plurality of servo actuators to load simultaneously, so as to improve the synchronism of the load loading and improve the test precision.

[0017] The present application also discloses a loading test method for an arch bridge model, which adopts the loading test system for the arch bridge model.

[0018] Step one: the load bearing counterforce frames are fixedly installed, the arc-shaped load beam is installed, and a plurality of load bearing counterforce frames are connected through the continuous beam.

[0019] Step two: the servo actuators are installed on the arc-shaped load beam and the continuous beam.

[0020] Step three: the loading test is performed on the test piece, and the size of the load is adjusted through the control system.

[0021] As described above, due to the adoption of the above technical scheme, the present application has the following beneficial effects:

[0022] 1. The present application proposes a loading test system and method for an arch bridge model, aiming at the problems of difficult loading and single loading direction in the loading of the arch bridge model test.

[0023] 2、The application can load arch bridge in multiple points and multiple directions, load K-shaped node with any opening angle, and load arch bridge in dynamic load and fatigue load test and test system, and through adjusting static electro-hydraulic servo actuator and bearing reaction frame, the arch bridge can be loaded in complex and arbitrary direction and position. The whole system has static load capacity for arch bridge model, can realize multiple point and multiple direction loading test of arch bridge model, complete simulation of vertical vehicle load and horizontal wind load, and realize multiple point and multiple direction load simulation of large scale arch bridge model by using arc bearing beam. The static load can simulate bearing capacity of bridge under short-term load effect and structural fatigue load of steel pipe arch.

[0024] 3、The dynamic electro-hydraulic servo actuator in the test system can provide lateral and vertical dynamic load for the arch bridge, and through the arc bearing beam, the arch bridge can be loaded in any angle, fatigue load test of the whole structure of the steel pipe concrete arch bridge can be realized, and dynamic fatigue load test of K-shaped node and cross-shaped node in the arch bridge can be realized. The application can provide various load application modes for the arch bridge, and can meet all load simulation of arch bridge test loading. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 is a structural schematic view of the bearing reaction frame in embodiment 1 of the application.

[0026] Figure 2 is Figure 1 A-A sectional view in figure.

[0027] Figure 3 is a structural schematic view of the bearing reaction frame in embodiment 2 of the application.

[0028] Figure 4 is a front view of the arch bridge model loading test system in the application.

[0029] Figure 5 is a top view of the arch bridge model loading test system in the application.

[0030] Figure 6 is a schematic view of the arch bridge model loading test system loading K-shaped node in the application.

[0031] Figure 7 is a schematic view of the arch bridge model loading test system loading whole arch bridge in the application.

[0032] Figure icon: figure icon: 11-first bearing reaction frame, 12-second bearing reaction frame, 13-third bearing reaction frame,

[0033] 101-Frame beam, 102-Frame column, 103-Arc-shaped loading beam, 104-Connecting beam, 105-Automatic lifting system, 106-Work platform, 107-Actuator connecting plate, 108-Tie rod, 109-Jack, 110-First horizontal beam, 111-Second horizontal beam, 112-Horizontal loading beam, 113-Horizontal loading longitudinal beam

[0034] 21-Static electro-hydraulic servo actuator, 22-First dynamic electro-hydraulic servo actuator, 23-Second dynamic electro-hydraulic servo actuator.

[0035] 3-Continuous beam, 4-Loaded crossbeam, 5-Reaction foundation, 6-K-byte point, 7-Reaction frame, 8-Arch bridge. Detailed Implementation

[0036] The present invention will now be described in detail with reference to the accompanying drawings.

[0037] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0038] Example 1

[0039] like Figure 4 , 5 As shown, a loading test system for an arch bridge model includes a servo actuator, multiple spaced load-bearing reaction frames, a dynamic oil distributor, pipelines, and a dynamic and static control system, etc. The multiple load-bearing reaction frames are connected by a continuous beam.

[0040] The load-bearing reaction frame includes a first load-bearing reaction frame 11, a second load-bearing reaction frame 12, and a third load-bearing reaction frame 13. One of these is a 300-ton load-bearing reaction frame (meaning it can withstand a vertical load of 3000kN), and the other two are 200-ton load-bearing reaction frames (meaning they can withstand a vertical load of 2000kN). The three load-bearing reaction frames adopt a self-balancing structure, have a semi-automatic lifting function, and are placed on the reaction foundation 5.

[0041] like Figure 1 , 2As shown, each bearing counterforce frame includes a frame crossbeam 101, a frame column 102, an arc-shaped loading beam 103, a connecting crossbeam 104, an automatic lifting system 105, a working platform 106, an actuator connecting plate 107, a pull rod 108, a jack 109, a first horizontal beam 110, a second horizontal beam 111, and the like. The connecting crossbeam 104 is arranged at the top of the bearing counterforce frame and is used to connect the frame column 102. The frame crossbeam 101 and the arc-shaped loading beam 103 are fixedly connected and arranged inside the bearing counterforce frame. The arc-shaped loading beam 103 is fixed below the frame crossbeam 101, and the bottom surface of the arc-shaped loading beam 103 is an arc surface (adapted to the top surface of the arch bridge). The arc surface of the arc-shaped loading beam 103 is provided with a plurality of actuator connecting plates 107, and the servo actuators can be connected through the actuator connecting plates 107. Preferably, the central angle of the arc-shaped loading beam is greater than 90 degrees and less than or equal to 180 degrees, so as to facilitate multi-point and multi-direction loading. The frame crossbeam 101 is connected with the automatic lifting system 105, and the automatic lifting system 105 can be used to realize hydraulic automatic lifting, and the space can be adjusted by manual locking. The working platform 106 at the bottom of the bearing counterforce frame is connected with the counterforce foundation 5 through an anchor bolt.

[0042] The three bearing counterforce frames are connected through a continuously arranged horizontal beam 3. Specifically, in the embodiment, the continuously arranged horizontal beam 3 is connected with the frame crossbeam 101 of each bearing counterforce frame, and the height of the frame crossbeam 101 can be adjusted through the automatic lifting system 105, so as to adjust the height of the continuously arranged horizontal beam 3. Two loading crossbeams 4 are also arranged horizontally between the bearing counterforce frames. The two loading crossbeams 4 are long horizontal beams and are arranged at a height of 2250 mm and 5500 mm from the working platform 5, respectively. The continuously arranged horizontal beam 3 is provided with a plurality of servo actuators for vertical loading. The installation positions of the servo actuators on the continuously arranged horizontal beam 3 are adjustable. The loading crossbeams 4 are provided with a plurality of servo actuators for horizontal loading, which can include at least one static servo actuator and at least one dynamic servo actuator. The horizontal load can simulate the horizontal effect of the arch bridge under the action of wind load, and the out-of-plane stability of the arch bridge can be tested and researched.

[0043] In the embodiment, the servo actuators include one static electro-hydraulic servo actuator 21, one first dynamic electro-hydraulic servo actuator 22, and eight second dynamic electro-hydraulic servo actuators 23. The static electro-hydraulic servo actuator 21 can be selected as a 300-ton static electro-hydraulic servo actuator, the first dynamic electro-hydraulic servo actuator 22 can be selected as a 100-ton dynamic electro-hydraulic servo actuator, and the second dynamic electro-hydraulic servo actuator 23 can be selected as a 25-ton dynamic electro-hydraulic servo actuator. The 300-ton static electro-hydraulic servo actuator is connected to the frame cross beam 101 through an auxiliary device. The 100-ton dynamic electro-hydraulic servo actuator can be connected to the frame cross beam 101. The 25-ton dynamic electro-hydraulic servo actuator can be installed at any position in the load reaction frame and is used for multi-point and multi-directional loading. The dynamic electro-hydraulic servo actuator can provide vertical and horizontal dynamic loads for the arch bridge and can provide a test means for the fatigue failure of the arch bridge under the action of loads.

[0044] The 300-ton static electro-hydraulic servo actuator is mainly used for mechanical property tests of large bridge components and nodes and is used for vertical loading in the load reaction frame. The 300-ton static electro-hydraulic servo actuator includes an actuator body, a front spherical hinge and a rear flange connection, an embedded magnetostrictive displacement sensor, a spoke-type high-precision load sensor, and corresponding connecting pieces. The 100-ton dynamic electro-hydraulic servo actuator is mainly used for fatigue tests of large bridge components and includes an actuator body, a servo valve, a load sensor, a displacement sensor, front and rear high-precision spherical hinges, and other supporting devices. The 25-ton dynamic electro-hydraulic servo actuator is mainly used for multi-point and multi-directional dynamic loading tests of large bridge components and includes an actuator body, a servo valve, a load sensor, a displacement sensor, front and rear high-precision spherical hinges, and other supporting devices.

[0045] The dynamic and static control system includes two sets of four-channel controllers. Each set of controller has four control channels and can control up to eight actuators to simultaneously load and complete coordinated loading tests. The controllers are connected in a network to achieve mutual and coordinated loading control of the actuators of the two sets of systems and complete more complex structural component loading tests. Full-digital closed-loop control of the eight actuators can be achieved. Each channel is equipped with two closed-loop control loops of test force and displacement. The two control modes can be smoothly switched under any condition to meet the dynamic and static loading requirements of tests. The control system can accept data of force or displacement sensors (except for the sensors of the actuators) for closed-loop control. Test parameters can be transmitted to a data acquisition system in a digital or analog output mode for analysis and calculation of test results.

[0046] Embodiment 2

[0047] As Figure 3As shown, the embodiment in this embodiment is based on the embodiment 1, inside the bearing counterforce frame is additionally provided with horizontal loading beam, the horizontal loading beam includes mutually connected horizontal loading longitudinal beam 113 and horizontal loading cross beam 112. The horizontal loading beam is installed on the automatic lifting system 105, and the height of the horizontal loading beam can be adjusted through the automatic lifting system 105. The horizontal loading beam is installed with servo actuator (which can include static servo actuator and / or dynamic servo actuator), and the servo actuator installed on the horizontal loading beam is used for horizontal loading.

[0048] Embodiment 3

[0049] A method for loading test of arch bridge model, using the loading test system for arch bridge model of embodiment 1 or 2, comprising the following steps:

[0050] Step one: first, connect the working platform 106 with the counterforce foundation 5 through anchor bolt, and then connect the three bearing counterforce frames with the working platform 106 through anchor bolt. Install the arc-shaped loading beam 103 and the continuous beam 3.

[0051] Step two: after the structure is installed, install the static electro-hydraulic servo actuator and the dynamic electro-hydraulic servo actuator. According to the different load size requirements of the test loading, the type and tonnage of the servo can be replaced. And according to the different loading positions, the horizontal position and vertical height of the servo can be changed.

[0052] Step three: place the test component on the working platform 106. For large components such as large-span bridges, the three bearing counterforce frames can be installed across, and for small components such as K-shaped nodes and cross-shaped nodes, the test component can be installed on one bearing counterforce frame. After the test component is installed, the position of the electro-hydraulic servo actuator can be adjusted to apply load in different positions and directions, and the size of the load can be adjusted through the control of the system.

[0053] Preferably, step one can also include installing the loading cross beam 4 (long horizontal beam) near the height of 2250mm and 5500mm of the column from the working table surface, and testing whether the installation precision meets the requirements. After the installation of the loading cross beam 4 is completed, install the horizontal loading longitudinal beam 113 and the horizontal loading cross beam 112 (short horizontal beam).

[0054] As Figure 6As shown, the K-shaped node 6 of the arch bridge model loading test system is loaded, and through installation of corresponding static and / or dynamic electro-hydraulic servo actuators, multi-point and multi-direction loading can be carried out, and bearing capacity test and fatigue performance test can be realized. The middle arc-shaped loading beam 103 of the bearing reaction frame can load the K-shaped node of the steel pipe concrete arch bridge, the arc-shaped loading beam 103 cooperates with the dynamic electro-hydraulic servo to realize dynamic load test of the K-shaped node, and fatigue load test. The arc-shaped loading beam 103 cooperates with the static electro-hydraulic servo to realize strength load test of the K-shaped node. The arc-shaped loading beam 103 can also be used for dynamic and static load test of other complex forms of arch bridge local frames, such as various steel structure nodes, special-shaped nodes and various components.

[0055] As shown in the figure, Figure 7 As shown, the arch bridge 8 of the arch bridge model loading test system is loaded, and through installation of corresponding static and / or dynamic electro-hydraulic servo actuators, multi-point and multi-direction loading can be carried out, and the added reaction frame 7 on both sides can realize bearing capacity test and fatigue performance test of the arch bridge 8. The loading beam 4 installed in the bearing reaction frame can apply horizontal static load and dynamic load to the test product, and when the cross-shaped node is loaded, horizontal and vertical loads can be applied at the same time, not only the strength test can be carried out, but also the fatigue test under dynamic load can be carried out.

[0056] The above is only the preferred embodiment of the present application, and is not used to limit the present application, any modification, equivalent replacement and improvement within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. An arch bridge model loading test system, characterized in that, The application relates to a loading test system for an arch bridge model, which comprises servo actuators, a control system and a plurality of interval-arranged load-bearing counterforce frames, the plurality of load-bearing counterforce frames are connected through continuous beams, at least one of the servo actuators is a static servo actuator and at least one is a dynamic servo actuator, the load-bearing counterforce frames are provided with frame crossbeams and arc-shaped loading beams, the arc-shaped loading beams are fixedly connected to the lower parts of the frame crossbeams, the bottom surfaces of the arc-shaped loading beams are arc surfaces, the frame crossbeams can drive the arc-shaped loading beams to automatically ascend and descend, the arc-shaped loading beams and the continuous beams are provided with a plurality of servo actuators, and the control system is used for controlling the servo actuators. The bottom surfaces of the arc-shaped loading beams are provided with a plurality of actuator connecting plates which are used for connecting the servo actuators. The load-bearing counterforce frames are internally provided with horizontal loading beams, the horizontal loading beams are provided with the servo actuators, and the servo actuators installed on the horizontal loading beams are used for horizontal loading. The horizontal loading beams comprise horizontally-connected horizontal loading longitudinal beams and horizontal loading crossbeams.

2. The system for loading test of arch bridge model according to claim 1, characterized in that, The central angle of the arc-shaped loading beams is greater than 90 degrees and less than or equal to 180 degrees.

3. The system for loading test of arch bridge model according to claim 1, characterized in that, The working platforms at the bottom parts of the load-bearing counterforce frames are further provided with horizontal beams, and the horizontal beams are connected with jacks.

4. The system for loading test of arch bridge model according to claim 1, characterized in that, The load-bearing counterforce frames are connected with loading crossbeams, the loading crossbeams are provided with the servo actuators, and the servo actuators installed on the loading crossbeams are used for horizontal loading.

5. The system for loading test of arch bridge model according to claim 4, characterized in that, The continuous beams and the loading crossbeams are horizontally arranged and are connected with at least two servo actuators, and the installation positions of the servo actuators can be adjusted.

6. The system for loading test of arch bridge model according to any one of claims 1-5, characterized in that, The control system comprises a plurality of control channels, each control channel is provided with two closed-loop control loops of test force and displacement, and the control system can control a plurality of servo actuators to simultaneously load.

7. A method for loading test of an arch bridge model, characterized in that, The application adopts the loading test system for the arch bridge model, and the loading test system comprises the following steps: Step one: fixing and installing the load-bearing counterforce frames, installing the arc-shaped loading beams and connecting a plurality of load-bearing counterforce frames through continuous beams; Step two: installing the servo actuators on the arc-shaped loading beams and the continuous beams; Step three: loading test on a test piece, and adjusting the load size through the control system.

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