CN113092047B

CN113092047B - Prefabricated assembled continuum model box for simulating underground structure under combined action of fault and seismic motion

Info

Publication number: CN113092047B
Application number: CN202110524725.0A
Authority: CN
Inventors: 韩俊艳; 王小强; 王丕光; 金浏; 郭之科; 杜修力
Original assignee: Beijing University of Technology
Current assignee: Beijing University of Technology
Priority date: 2021-05-14
Filing date: 2021-05-14
Publication date: 2022-10-11
Anticipated expiration: 2041-05-14
Also published as: CN113092047A

Abstract

A prefabricated assembly type continuum model box for simulating an underground structure under the combined action of fault dislocation and seismic oscillation belongs to the field of geotechnical seismic engineering. The device comprises two end boxes arranged on the table tops of two adjacent vibrating tables and a middle box connected with the end boxes. The end box is a layered shearing box formed by connecting a plurality of layers of U-shaped frames, and adjacent frames are connected by a sliding rail, so that the horizontal shearing of a soil body can be effectively simulated. The middle box is a soft connection box and is composed of a plurality of layers of rectangular steel frames, the frames and the end box and the middle box are connected through telescopic devices, and meanwhile, slideways are arranged at corresponding connection positions, and the influence of fault dislocation is simulated through relative displacement between the frames. In order to reduce the friction of the bottom of the mold box with the support brackets, two sliding ball joints are mounted below each frame of the middle box. And the middle box are placed on the supporting bracket together, so that the bearing capacity of the model device is effectively increased.

Description

Prefabricated assembled continuum model box for simulating underground structure under combined action of fault and seismic motion

Technical Field

The invention provides a multi-array vibration table model test device for an underground structure, belongs to the field of geotechnical seismic engineering, and relates to a prefabricated assembly type model box for simulating the underground structure under the combined action of fault dislocation and seismic oscillation.

Background

With the large-scale development and construction of underground structures in China, the earthquake-resistant safety of the underground structures becomes a hot research problem in the field of earthquake engineering. Most of previous researches only consider the dynamic response of underground structures under the action of fault action or seismic wave propagation, and reports that more real simulation researches are simultaneously influenced by fault dislocation and seismic wave propagation are relatively rare.

In the earthquake-resistant research of the underground structure, the earthquake reaction characteristic of the underground structure is researched by means of a vibration table model test, the rationality of the existing result is identified, and the method becomes an effective means for researching the earthquake-resistant performance of the underground structure. In order to more reasonably simulate the seismic reaction of the underground structure when the underground structure is subjected to fault dislocation and seismic action, the reasonable design of the continuum model box for the multi-array vibration table test is particularly important.

The multiple array shaking table test is commonly used for the seismic reaction research of the multipoint non-uniform excitation of the long linear structure, namely, the multipoint non-uniform excitation of the earthquake is realized by applying different seismic accelerations to different table tops through a shaking table actuator. Considering that the fault dislocation displacement (three-direction six-degree-of-freedom X, Y, Z) can be applied to different table tops through the vibration table actuator, a multi-array vibration table array system can be used for researching the seismic reaction of the underground structure under the combined action of the fault dislocation and the seismic motion. The design of the continuum model box has the main functions of ensuring the continuity of soil around an underground structure, simulating the shear deformation of the soil when an earthquake occurs, and realizing the test simulation of simultaneously receiving fault dislocation and earthquake motion.

Disclosure of Invention

The model test device used in the past vibration table test can only consider the earthquake motion effect or fault dislocation. And the model device is often with higher costs, can not recycle, and the installation, demolish the construction degree of difficulty moreover great. In light of the defects of the prior art, the invention provides a prefabricated assembly type model box for simulating the combined action of fault dislocation and earthquake motion of an underground structure, which can also be applied to a vibration table test for singly considering fault dislocation or earthquake motion non-uniform excitation. The prefabricated member can be spliced and installed on site, and can be directly dismantled after the test is finished so as to be recycled.

The specific technical scheme of the invention is as follows:

a model test device for a multi-array vibration table of an underground structure comprises an end box, a middle box and a connecting device.

The end tank is a laminar shear tank. In the prior model device, a rigid box is often adopted as an end box, and the rigidity of the rigid box is too high, so that the horizontal shearing of a soil body is limited, and the accuracy of a test result is influenced. The layered shearing box used by the invention is formed by vertically superposing ten layers of U-shaped frames, and two adjacent U-shaped frames are connected by adopting a sliding rail device. The slide rail used by the invention is formed by splicing an upper part and a lower part, and is respectively arranged at the corresponding positions of the U-shaped frame through bolts. The upper part and the lower part of the sliding rail can relatively slide in the slideway, so that the relative displacement between the U-shaped frames is realized, and the horizontal shearing of soil is simulated. A plurality of bolt holes are reserved on the slideway, and bolts are installed in the reserved bolt holes to control the maximum relative shear displacement of each U-shaped frame during testing, so that different requirements of the testing on the maximum shear displacement of the soil body are met. The strength of the slide rails directly determines the bearing capacity of the end boxes, so the slide rails are made of high-strength steel. The bottom plate is made of a 40mm steel plate and is connected with the bottommost layer frame through bolts. Bolt holes are reserved in the bottom plates of the two end boxes and are fixed on the table surface of the vibration table through bolts during testing.

The middle box is a soft connection box and consists of a plurality of prefabricated rectangular steel frames. The frames and the end boxes and the middle box are connected through telescopic connecting devices, the side faces of the bottom cross beams of the frames are provided with slide ways, and the connecting devices are embedded into the slide ways, so that the frames can relatively move in a staggered manner, and the influence of fault movement on the simulation model device is realized. Bolt holes are reserved in the slide ways, and all or part of connecting devices can be fixed in the bolt holes through mounting bolts so as to realize independent consideration of seismic non-uniform excitation or simulation of fault fracture zones with different widths. During testing, the number of the rectangular steel frames in the middle box can be selected according to the length of the model structure so as to simulate the response of the model structures with different lengths.

To ensure the load-bearing capacity of the mold box, the intermediate box is placed on a support bracket. In order to reduce the friction of the bottom of the mold box with the support brackets, two sliding ball joints are mounted at the lower crosspiece of each frame of the intermediate box. The sliding spherical hinge consists of two parts, namely an upper spherical body and a lower pedestal, and is connected with the middle box through bolts.

The connecting device is formed by combining three steel cylinders and is telescopic. The rectangular frames are provided with grooves at both ends, and are embedded into the slideways during installation to connect the middle box with the end boxes and the middle box.

A layer of rubber membrane with the thickness of 10mm is laid on the inner walls of the end box and the middle box, so that the soil body and the structure can be borne, the structure-soil body can be separated from the model device during the test, the structure-soil body is not in direct contact with the model device, and the influence of the boundary effect can be effectively reduced.

Compared with the prior art, the invention has the following remarkable characteristics:

1. the end box adopts a layered shearing box, so that the influence of the boundary effect of the model box is reduced, and the horizontal shearing of soil is effectively simulated.

2. The U-shaped frames in the layered shearing box are connected through the sliding rails, so that the requirement on bearing capacity is met, and the shearing displacement of the soil body can be manually controlled.

3. The frames of the middle box and the end boxes and the middle box are connected through telescopic connecting devices, and all or part of the connecting devices can be fixed in the slide ways through mounting bolts, so that fault dislocation or earthquake non-uniform excitation is considered independently, and the combined action of the fault dislocation and the earthquake non-uniform excitation can also be considered simultaneously.

4. The device is a detachable prefabricated model and is connected with a connecting device by bolts. The prefabricated parts can be manufactured in advance, and can be assembled and tested on site and then can be disassembled and recycled during testing, so that the prefabricated parts are economical and environment-friendly.

Drawings

Fig. 1 is an oblique view of the device after assembly.

Fig. 2 is a front view of the device after assembly.

Fig. 3 is an oblique view of the end box of the device.

FIG. 4 is an oblique view of the intermediate box of the apparatus.

Fig. 5 is a schematic view of the device after installation.

FIG. 6 is a schematic view of the rubber membrane laid inside the device.

Fig. 7 is a schematic view of the junction of the present device.

Fig. 8 is a schematic view of the sliding ball hinge device of the present invention.

Fig. 9 is a schematic view of the connecting device of the device.

Fig. 10 is a schematic view of the slide rail device of the present device.

Detailed Description

The following description of the present invention will be made with reference to the accompanying drawings 1 to 9.

The utility model provides a many battle array shaking table model test device of underground structure, installs on the shaking table, includes first end case 1, second end case 2, middle box 3, slip ball hank 4, articulated mounting 5, slide rail 6.

The bottoms of the end box 1 and the end box 2 are connected with the vibrating table through bolts, and a plurality of hole sites are arranged at the bottoms of the end box.

The end box 1,2 consists of U-shaped frames which are overlapped up and down, and the layers are connected by a slide rail 6 and used for simulating the horizontal shearing of the soil body. The slide rail 6 is formed by splicing an upper part and a lower part and is connected with the U-shaped frame through bolts. A plurality of bolt holes are reserved in the lower portion of the sliding rail 6, and the maximum shearing displacement of the soil body can be limited artificially by installing bolts in the bolt holes. The bottom plates of the end boxes 1 and 2 are made of steel and are connected with the bottom layer frame in a bolt connection mode.

The end tanks 1,2 are connected to the intermediate tank 3 by a connecting device 5. The connecting device 5 is embedded in a preset slideway, so that the relative dislocation of the end boxes 1 and 2 and the middle box 3 is realized.

The middle box 3 is composed of a plurality of layers of rectangular steel frames, each frame is provided with a 200mm long slideway at the corresponding connecting position, and the frames are connected through a connecting device 5.

The connecting device 5 is formed by combining three steel cylinders, is telescopic and is arranged in a reserved slide way through a groove at the end part. Bolt holes are arranged in the reserved slide ways, and the connecting device 5 can be fixed in the slide ways through bolts. During the test, all the connecting devices 5 are fixed, and the earthquake motion effect can be independently simulated. If the fixed part is connected with the device 5, the combined action of fault dislocation and earthquake motion can be simulated.

The sliding spherical hinge 4 is arranged at the lower part of a bottom cross beam of each layer of framework of the middle box 3 through a bolt and is placed on the supporting bracket together with the middle box 3, so that the friction effect between the middle box 3 and the supporting bracket is reduced.

Claims

1. The utility model provides a many battle array shaking table model test device of underground structure which characterized in that: comprises two end boxes and a middle box; the end box is a layered shearing box formed by vertically overlapping U-shaped steel frames, and the adjacent U-shaped steel frames are connected together by adopting a sliding rail; the sliding rail is formed by splicing an upper part and a lower part and is connected with the U-shaped steel frame through bolts; a plurality of bolt holes are reserved in the lower part of the slide rail, and the maximum shearing displacement of the soil body is limited by installing bolts in the bolt holes;

the middle box is a soft connection box consisting of a plurality of layers of rectangular steel frames; the middle box is formed by connecting all rectangular steel frames of the middle box and end boxes and the middle box through telescopic connecting devices, a slide way is arranged on the side surface of a cross beam at the bottom of each rectangular steel frame, and the connecting devices are arranged in the reserved slide way through grooves at the ends of the connecting devices;

the slideway in each rectangular steel frame of the middle box is provided with a bolt hole, the bolt hole and the bolt form a limiting device, and the connecting device is fixed by fastening bolts in all the bolt holes during test so as to realize independent seismic oscillation non-uniform excitation; or fastening bolts in part of the bolt holes to fix part of the connecting device, so that the combined action of earthquake motion and fault dislocation is realized.

2. The test device for the model of the multi-array vibration table with the underground structure as claimed in claim 1, wherein: the device is a prefabricated assembled model box, is assembled through mounting bolts on site during testing, and can be detached and recycled after testing.