CN-116026707-B - Multi-time unidirectional impact load test simulation device and method under gradient confining pressure

CN116026707BCN 116026707 BCN116026707 BCN 116026707BCN-116026707-B

Abstract

The application discloses a multi-time unidirectional impact load test simulation device and method under gradient confining pressure, wherein the rail comprises a horizontal section, one end of the horizontal section is connected with a slope section, the sample is positioned at the horizontal section, a gradient confining pressure device is arranged outside the sample to pressurize the sample, the plurality of impact objects are respectively released from different heights of the slope section from the ground and move along the rail and sequentially collide with the sample as power input sources to apply multi-time unidirectional impact load to the sample, the plurality of impact objects can be sequentially nested, so that the impact objects which collide with the sample at first can cross the impact objects which collide with the sample at first to avoid collision of the impact objects.

Inventors

YANG FANJIE
LIU XIAOYAN
CHEN HONGJIE
YANG LI
ZHOU HUI
TANG RONGPING
QIN YULAN
XU CONGYUN
LI HAN
SUN BOWEN

Assignees

中国科学院武汉岩土力学研究所
华能澜沧江水电股份有限公司
中国电建集团中南勘测设计研究院有限公司

Dates

Publication Date: 20260505
Application Date: 20221128

Claims (8)

1. The utility model provides a gradient confining pressure is down a plurality of unidirectional impact load test analogue means which characterized in that includes: the track comprises a horizontal section, and one end of the horizontal section is connected with a slope section; The sample is positioned at the horizontal section, and a gradient confining pressure device is arranged outside the sample to pressurize the sample; The impact objects are respectively released from different heights of the slope section from the ground as power input sources, move along the track and sequentially collide with the sample so as to apply a plurality of unidirectional impact loads to the sample; The plurality of the impactors can be nested in sequence, so that the impactors which collide with the sample later can cross the impactors which collide with the sample earlier, and the impactors are prevented from colliding with each other; the gradient confining pressure device comprises: The test samples are positioned in the confining pressure sleeve, and a connecting wing plate is arranged on the confining pressure sleeve; The confining pressure adjusting device is arranged on each group of connecting wing plates of the confining pressure sleeve so as to adjust the confining pressure of the confining pressure sleeve and enable a plurality of groups of confining pressure of the confining pressure sleeve to be distributed in a gradient mode, and comprises adjusting bolts and nuts, and the confining pressure of the confining pressure sleeve is adjusted by adjusting the tightening degree of the nuts.
2. The gradient confining pressure multi-time unidirectional impact load test simulation device according to claim 1, wherein the impact object comprises a frame body and a hollow part formed by wrapping the frame body, an opening part is arranged at the bottom of the frame body, the sizes of the frame bodies of the impact objects and the opening part are sequentially increased along with the increase of the height of the impact objects from the ground, and the impact objects can be sequentially nested and contained in the hollow part through the opening part.
3. The multi-time unidirectional impact load test simulation device under gradient confining pressure according to claim 2, wherein the opening is close to the track, pulleys are arranged at the opening, sliding grooves which are in one-to-one correspondence with the pulleys are arranged on the slope section and the horizontal section of the track, and the impact objects move along the sliding grooves through the pulleys.
4. The simulation device for the multi-time unidirectional impact load test under the gradient confining pressure according to claim 3, wherein the quality of a plurality of impact objects is the same, and the radial size of the frame bodies of the impact objects is sequentially increased, and the axial size of the frame bodies of the impact objects is sequentially decreased.
5. The gradient confining pressure multi-time unidirectional impact load test simulation device according to claim 1, wherein the confining pressure sleeve comprises a C-shaped confining pressure plate, the connecting wing plates are arranged at the end-to-end joint of the confining pressure plate, deformation spaces are formed between the two connecting wing plates, and the two connecting wing plates are pressurized and fixed through the confining pressure adjusting device.
6. The gradient confining pressure multi-time one-way impact load test simulation device according to claim 5, wherein the gradient confining pressure device further comprises a pressure sensor, and the pressure sensor is arranged between the two connecting wing plates of each group of confining pressure sleeves so as to monitor the confining pressure of each group of confining pressure sleeves.
7. The gradient confining pressure multi-time unidirectional impact load test simulation device according to claim 6, wherein rollers are arranged at the bottoms of the confining pressure sleeves, grooves matched with the rollers are formed in the horizontal sections of the rails, and the confining pressure sleeves and the samples in the confining pressure sleeves move along the grooves through the rollers.
8. The multi-time one-way impact load test simulation device under gradient confining pressure according to claim 7, wherein the sample is a cylindrical rock sample device and is clamped in the confining pressure sleeve.

Description

Multi-time unidirectional impact load test simulation device and method under gradient confining pressure Technical Field The application relates to the technical field of blasting load impact tests, in particular to a device and a method for simulating multiple unidirectional impact load tests under gradient confining pressure. Background In the blasting construction process of the underground cavity, a millisecond delay sectional blasting technology is generally adopted, the formed blasting load can impact surrounding rock for a plurality of times in a short time, and meanwhile, the stress of the original rock is redistributed due to excavation, so that the shallow part of the surrounding rock of the outline surface of the cavity can form an uneven gradient stress state. Based on the field construction background, along with the promotion of blasting excavation progress, the stress state of surrounding rocks of an underground cavity is continuously changed, the blasting damage degree of the surrounding rocks is continuously increased, the damage and instability of the surrounding rocks can be possibly caused, and the safe construction of the underground cavity is further affected. Therefore, in order to ensure the stability of the surrounding rock of the underground cavity in the construction period, the damage effect of the continuous blasting load on the stress state of the surrounding rock is required to be continuously adjusted for a plurality of times, so that the blasting parameters or supporting measures on site are adjusted in a targeted manner. However, such research experiments involve two key issues, (1) how to achieve a sample in a gradient confining pressure state, and (2) how to control the impact load pulse size and time interval. The existing test device is difficult to meet the requirements at the same time. Disclosure of Invention The embodiment of the application provides a device and a method for simulating multiple unidirectional impact load tests under gradient confining pressure, which can realize that a sample is under gradient confining pressure and can apply unidirectional impact load to the sample for multiple times so as to simulate the problem of blasting damage effect of the surrounding rock with the stress state continuously changed by multiple blasting loads in underground engineering, and the technical scheme is as follows: The application provides a multi-time unidirectional impact load test simulation device under gradient confining pressure, which comprises a track, a sample and a plurality of impact objects, wherein the track comprises a horizontal section, one end of the horizontal section is connected with a slope section, the sample is positioned at the horizontal section, a gradient confining pressure device is arranged outside the sample to pressurize the sample, the impact objects are respectively released from different heights of the slope section from the ground and move along the track as power input sources and sequentially collide with the sample to apply multi-time unidirectional impact load to the sample, and the impact objects can be sequentially nested so that the impact objects which collide with the sample later can cross the impact objects which collide with the sample earlier to avoid mutual collision of the impact objects. For example, in the gradient confining pressure multi-time unidirectional impact load test simulation device provided in one embodiment, the impact object includes a frame body and a hollow portion formed by wrapping the frame body, an opening is provided at the bottom of the frame body, and the sizes of the frame bodies of the impact object and the opening are sequentially increased along with the increase of the height of the impact object from the ground, and the impact object and the opening can be sequentially nested and accommodated in the hollow portion through the opening. For example, in the simulation device for multiple unidirectional impact load tests under gradient confining pressure provided in one embodiment, the opening is close to the track, the opening is provided with pulleys, the slope section and the horizontal section of the track are provided with sliding grooves corresponding to the pulleys one by one, and the impact object moves along the sliding grooves through the pulleys. For example, in the simulation device for multiple unidirectional impact load tests under gradient confining pressure provided in one embodiment, the quality of a plurality of impact objects is the same, and the radial dimensions of the frames of the impact objects are sequentially increased and the axial dimensions of the frames of the impact objects are sequentially decreased. For example, in the gradient confining pressure multi-time unidirectional impact load test simulation device provided by one embodiment, the gradient confining pressure device comprises a plurality of groups of confining pressure sleeves and confining pressure