Beam type synchronous lifting follow-up bracket system for tunnel non-uniform vibration table test and test method

Abstract

The invention provides a beam type synchronous lifting follow-up bracket system for a tunnel non-uniform vibration table test and a test method. The beam type synchronous lifting follow-up bracket system is composed of a mounting base, a cushion block, a follow-up box bracket, a lifting frame, a mounting truss, an adjusting wedge block and a lifting oil cylinder. The mounting base is used for supporting the cushion block and mounting the truss; the lifting frame provides support for the mounting truss and the follow-up box bracket during sample loading, and the lifting frame is supported by the table board of the vibration table. The lifting oil cylinder is used for connecting the lifting frame and the vibration table top. The adjusting wedge block is installed between the cushion block and the installation truss and used for compensating a gap between the cushion block and the installation truss. It can be guaranteed that the follow-up box and the driving box are located on the same horizontal plane in a vibration table test, and non-uniform seismic excitation can be effectively simulated.

Description

Technical Field

[0001] This invention relates to the field of underground structure testing equipment technology, and more specifically, to a beam-type synchronous lifting follower bracket system and testing method for tunnel non-uniform shaking table testing. Background Technology

[0002] In the field of seismic resistance research for tunnels and underground engineering, traditional analysis methods are mostly based on the assumption of uniform seismic excitation, which assumes that all parts of the structure experience the same seismic motion time history. However, in actual earthquakes, due to factors such as differences in geological structure, the traveling wave effect of seismic waves, and local site filtering, seismic motions exhibit significant spatial inconsistencies in amplitude, phase, and spectrum. For longitudinally extending underground structures such as tunnels, this non-uniform excitation may induce unique seismic damage such as axial tensile-compressive failure and joint misalignment.

[0003] Current research on non-uniform excitation mainly relies on numerical simulation, but due to model simplification, it is difficult to fully reflect the influence of actual complex wave fields. Although shaking table tests can simulate seismic action more realistically, conventional single or parallel shaking table systems can only achieve uniform excitation and cannot reproduce the spatial variability of seismic waves.

[0004] While several shaking table systems have emerged in recent years, their high equipment costs, complex collaborative control, and difficulty in achieving continuous spatial displacement loading for long-line structural models such as tunnels are significant challenges. Especially for sections with varying longitudinal curvature in tunnels, existing testing devices lack adaptive support capabilities to accommodate differences in model elevation, leading to distortion of soil boundary conditions. Therefore, there is an urgent need to develop a testing system capable of flexibly adjusting elevation and collaboratively simulating spatially non-uniform seismic motions to fill the gap in non-uniform shaking table testing and methods, providing a reliable basis for tunnel seismic design. Summary of the Invention

[0005] To address the technical problems mentioned above, this invention provides a beam-type synchronous lifting follower bracket system and testing method for tunnel non-uniform shaking table tests.

[0006] This invention provides a beam-type synchronous lifting follower bracket system for tunnel non-uniform shaking table tests. The system is mounted on a grooved mounting surface and includes a follower box bracket, mounting bases on both sides of the groove, and a lifting frame within the groove. The follower box bracket is connected to the lifting frame via a mounting truss. The mounting truss is a flipped "V"-shaped frame, with both sides mounted on the mounting base and the middle section connected to the lifting frame.

[0007] Furthermore, the mounting base and the mounting truss support are provided with pads and adjusting wedges. The pads are connected to the mounting truss by bolts, and the adjusting wedges are installed between the pads and the mounting truss to compensate for the gap between the pads and the mounting truss.

[0008] Furthermore, the mounting truss and the lifting frame are detachably connected.

[0009] Furthermore, the lifting frame is connected to the vibration table platform via a lifting cylinder.

[0010] The present invention also provides a test method based on the above-mentioned beam-type synchronous lifting follow-up bracket system, comprising the following steps:

[0011] S1. Fix the mounting base on the mounting surface, place both sides of the mounting truss on the mounting base respectively, and align the empty spaces;

[0012] S2. Connect the lifting frame to the vibrating table surfaces at both ends using lifting cylinders;

[0013] S3. After the sample is loaded, the vibration table and the follower box bracket table rise simultaneously, and the installation truss and follower box bracket rise together through the lifting frame.

[0014] S4. After raising to the working position, insert pads and adjusting wedges between the mounting base and the mounting truss, then release the lifting cylinder of the lifting frame and remove the lifting frame.

[0015] S5. After that, the top plane of the follower box bracket is on the same horizontal plane as the vibration table surface, and it can move in six degrees of freedom in three directions (vertical, horizontal, front-back, left-right).

[0016] S6, the active box and the follower box are connected by a flexible connecting rod, and synchronous excitation is achieved after the vibration table is turned on.

[0017] The beneficial effects of this invention are as follows:

[0018] This invention relates to a beam-type liftable follower bracket system and testing method for non-uniform shaking table tests in tunnels. The follower bracket system consists of a mounting base, pads, a follower box bracket, a lifting frame, a mounting truss, adjusting wedges, and a lifting cylinder. The mounting base supports the pads and the mounting truss. The lifting frame provides support for the mounting truss and the follower box bracket during sample loading. The lifting frame is supported by the shaking table surface. The lifting cylinder connects the lifting frame and the shaking table surface. Adjusting wedges are installed between the pads and the truss to compensate for the gap between them. This invention ensures that the follower box and the active box are on the same horizontal plane during the shaking table test, effectively simulating non-uniform seismic excitation. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the installation of the present invention;

[0020] Figure 2 This is a schematic diagram of the mounting base structure of the present invention;

[0021] Figure 3 This is a schematic diagram of the pad structure of the present invention;

[0022] Figure 4 This is a schematic diagram of the lifting frame structure of the present invention;

[0023] Figure 5 This is a schematic diagram of the truss installation for the present invention;

[0024] Figure 6 This is a schematic diagram of the adjusted wedge structure of the present invention;

[0025] Figure 7 This is a schematic diagram of the lifting cylinder structure of the present invention;

[0026] Figure 8 This is a schematic diagram illustrating the specific arrangement of the present invention;

[0027] In the diagram: 1-Mounting base, 2-Padded block, 3-Follower box bracket, 4-Lifting frame, 5-Mounting truss, 6-Adjusting wedge, 7-Lifting cylinder. Detailed Implementation

[0028] The exemplary embodiments of this disclosure are described below with reference to the accompanying drawings, including various details of the embodiments to aid understanding, and should be considered merely exemplary. Therefore, those skilled in the art will recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of this disclosure. Similarly, for clarity and brevity, descriptions of well-known functions and structures are omitted in the following description.

[0029] Please see Figure 1-8 This invention discloses a beam-type synchronous lifting follower bracket system for tunnel non-uniform vibration table testing. The system is installed on a grooved mounting surface and includes a follower box bracket 3, mounting bases 1 on both sides of the groove mounting surface, and a lifting frame 4 installed in the groove. The follower box bracket 3 is connected to the lifting frame 4 through a mounting truss 5. The mounting truss 5 is a flipped "U"-shaped frame. The two sides of the mounting truss 5 are mounted on the mounting base 1, and the middle position of the mounting truss 5 is connected to the lifting frame 4.

[0030] The mounting base 1 and the mounting truss 5 are equipped with pads 2 and adjusting wedges 6. The pads 2 are bolted to the mounting truss 5, and the adjusting wedges 6 are installed between the pads 2 and the mounting truss 5 to compensate for the gap between them. The mounting truss 5 and the lifting frame 4 are detachably connected, and the lifting frame 4 is connected to the vibration table surface via a lifting cylinder 7.

[0031] Preferably, the mounting surface can be the ground or other flat surfaces that are easy to install on.

[0032] First, fix the mounting base 1 to the ground, place the mounting truss 5 on the mounting base 1, and align the gaps; drill holes in the ground and install anchors with anchor bolts. When the vibration table is in the stopped position, the bottom surface of the mounting truss 5 is lower than the ground, and the top surface of the mounting truss 5 is higher than the ground.

[0033] During sample loading, the vibration table is in the stopped position, and the mounting truss 5 and the follower box bracket 3 are supported by the lifting frame 4, which in turn is supported by the vibration table surface. After sample loading, all three surfaces rise simultaneously, and the mounting truss 5 and the follower box bracket 3 rise together via the lifting frame 4.

[0034] The mounting base 1 is fixed on the ground. After the vibration table and the mounting truss 5 are raised from the stop position to the working position, the pad 2 and the adjusting wedge 6 are placed in, and then the pad 2 and the mounting truss 5 are connected with bolts. Since only gravity is applied during sample loading, the lifting frame 4 is not fixedly connected to the mounting truss 5. It is only hooked at the lifting position of the truss, and the lifting frame 4 can be removed when the hydraulic cylinder retracts.

[0035] Adjusting wedge 6 is installed between pad 2 and truss to compensate for the gap between pad 2 and truss. When the vibration table platform is raised from the theoretical stopping position to the theoretical working position, there is an error in the actual lifting height, so an adjusting wedge 6 is set to compensate for the error between theory and reality.

[0036] The present invention also provides a test method based on the above-mentioned beam-type synchronous lifting follow-up bracket system, comprising the following steps:

[0037] S1. Fix the mounting base 1 on the mounting surface, place the two sides of the mounting truss 5 on the mounting base 1 respectively, and align the empty spaces;

[0038] S2. Connect the lifting frame 4 to the vibrating table surfaces at both ends using the lifting cylinder 7;

[0039] S3. After the sample is loaded, the vibration table surface and the follower box bracket 3 surface rise simultaneously, and the lifting frame 4 drives the installation truss 5 and the follower box bracket 3 to rise together.

[0040] S4. After raising to the working position, insert the pad block 2 and the adjusting wedge block 6 between the mounting base 1 and the mounting truss 5, then release the lifting cylinder 7 of the lifting frame 4 and remove the lifting frame 4.

[0041] S5. After that, the top plane of the follower box bracket 3 is on the same horizontal plane as the vibration table surface, and it can move in six degrees of freedom in three directions (vertical, horizontal, front and back, left and right).

[0042] S6, the active box and the follower box are connected by a flexible connecting rod, and synchronous excitation is achieved after the vibration table is turned on.

[0043] The specific embodiments described above do not constitute a limitation on the scope of protection of this disclosure. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this disclosure should be included within the scope of protection of this disclosure.

Claims

1. A beam type synchronous lifting servo bracket system for tunnel non-uniform shaking table test, arranged on a mounting surface with a groove, characterized in that: The installation base and the installation truss support are provided with a cushion block and an adjusting wedge, the cushion block is connected with the installation truss through a bolt, and the adjusting wedge is installed between the cushion block and the installation truss and is used for compensating the gap between the cushion block and the installation truss.

2. The beam type synchronous lifting follower carriage system for tunnel non-uniform shaking table test according to claim 1, characterized in that: The installation truss and the lifting frame are detachably connected.

3. The beam type synchronous lifting follower trolley system for tunnel non-uniform shaking table test according to claim 1, characterized in that: The lifting frame is connected with a vibration table table top through a lifting oil cylinder.

4. The beam type synchronous lifting follower trolley system for tunnel non-uniform shaking table test according to claim 1, characterized in that: The method comprises the following steps:

5. A test method for a beam synchronous hoist and follow-up carriage system according to any one of claims 1 to 4, characterized in that S1, the installation base is fixed on the installation surface, the two sides of the installation truss are respectively placed on the installation base, and the gap is aligned; S2, the lifting frame is connected with the two-end vibration table table top through the lifting oil cylinder; S3, after the sample is installed, the vibration table table top and the follow-up box bracket table top are simultaneously lifted, the installation truss and the follow-up box bracket are driven to be lifted together through the lifting frame; S4, after being lifted to the working position, the cushion block and the adjusting wedge are installed between the installation base and the installation truss, then the lifting oil cylinder of the lifting frame is loosened, and the lifting frame is removed; S5, thereafter, the top plane of the follow-up box bracket and the vibration table table top are in the same horizontal plane, and the vertical, horizontal front and back and left and right three directions are all movable; S6, the main box and the follow-up box are connected through a flexible connecting rod, and synchronous excitation is realized after the vibration table is started. ​

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