CN-122016492-A - Rock-soil body mechanical parameter measurement system and method

CN122016492ACN 122016492 ACN122016492 ACN 122016492ACN-122016492-A

Abstract

The invention discloses a rock-soil body mechanical parameter measurement system and method, wherein the system comprises an elastic sleeve, a sensing optical cable, an optical fiber demodulation instrument, a pressure source, a pressure control structure and a data analysis mechanism, wherein the elastic sleeve is used for being implanted into a rock-soil body and is internally provided with a deformation cavity, the sensing optical cable is distributed along the axial direction of the elastic sleeve and is in contact with the elastic sleeve, the optical fiber demodulation instrument is electrically connected with the sensing optical cable and can demodulate an optical signal of the sensing optical cable to generate optical cable measurement data, the pressure source is used for providing pressure fluid, the pressure source can be communicated with the deformation cavity through the pressure control structure, the pressure detection mechanism is used for collecting the pressure data of the deformation cavity, and the data analysis mechanism is used for analyzing and processing the pressure data and the optical cable measurement data to generate the mechanical parameters of the rock-soil body. According to the invention, the sensing optical cables are distributed along the axial direction of the elastic sleeve and are contacted with the elastic sleeve, the distributed measurement of the mechanical parameters of the rock-soil body can be realized by analyzing the relation between the signal change of the sensing optical cables and the change of the rock-soil body, and the measurement result is more accurate.

Inventors

LI HAOJIE
XU RUINA
JIANG PEIXUE
ZHANG KAI

Assignees

清华大学
北京怀柔实验室

Dates

Publication Date: 20260512
Application Date: 20260120

Claims (12)

1. A system for measuring a mechanical parameter of a rock and earth mass, comprising: the elastic sleeve is used for being implanted into a rock-soil body and is internally provided with a deformation cavity; the sensing optical cables are distributed along the axial direction of the elastic sleeve and are in contact with the elastic sleeve; The optical fiber demodulator is electrically connected with the sensing optical cable and can demodulate the optical signal of the sensing optical cable to generate optical cable measurement data; a pressure source for providing a pressure fluid; the pressure control structure is used for enabling the pressure source to be communicated with the deformation cavity; The pressure detection mechanism is used for collecting pressure data of the deformation cavity; and the data analysis mechanism is used for analyzing and processing according to the pressure data and the optical cable measurement data to generate the mechanical parameters of the rock-soil body.
2. A rock-soil body mechanical parameter measuring system as claimed in claim 1, wherein, The sensing optical cable is spirally wound on the inner wall surface or the inner wall body of the elastic sleeve along the axial direction of the elastic sleeve.
3. A rock-soil body mechanical parameter measuring system as claimed in claim 2, wherein, An included angle is formed between the sensing optical cable and the radial direction of the elastic sleeve, and the included angle is smaller than 5 degrees.
4. A rock-soil body mechanical parameter measuring system as claimed in any one of claims 1 to 3, The optical cable measurement data comprises a temperature measurement result and a strain measurement result of the sensing optical cable; The sensing optical cable is a composite sensing optical cable and is provided with a temperature sensing optical fiber and a strain sensing optical fiber; The optical fiber demodulator is a composite optical fiber demodulator, the composite optical fiber demodulator comprises at least one temperature optical fiber demodulation module and at least one strain optical fiber demodulation module, the temperature optical fiber demodulation module is electrically connected with the temperature sensing optical fiber and can demodulate and process the optical signal of the temperature sensing optical fiber into the temperature measurement result, and the strain optical fiber demodulation module is electrically connected with the strain sensing optical fiber and can demodulate and process the optical signal of the strain sensing optical fiber into the strain measurement result.
5. A rock-soil body mechanical parameter measuring system as claimed in claim 1, wherein, Still be equipped with circulation structure and a plurality of packing structures in the elastic sleeve, circulation structure is followed elastic sleeve's axial wears to locate in the elastic sleeve, circulation structure with have the annular space between the elastic sleeve, annular space constitutes warp the chamber, a plurality of packing structures are followed warp the axial interval in chamber arranges and will elastic sleeve separates and forms a plurality of deformation sections just warp the chamber by separating and forms a plurality of deformation subchambers, each deformation subchamber passes through circulation structure with the accuse is pressed the structure and is linked together.
6. A rock-soil body mechanical parameter measuring system as claimed in claim 5, wherein, The pressure detection mechanism comprises an underground pressure detection structure, a signal transmission optical cable and a plurality of optical fiber pressure gauges, wherein the optical fiber pressure gauges are arranged in series on the signal transmission optical cable and are correspondingly distributed in the deformation sections; The optical fiber demodulation instrument is further provided with at least one pressure optical fiber demodulation module, and the pressure optical fiber demodulation module is electrically connected with the signal transmission optical cable and can demodulate and process optical signals of the optical fiber pressure gauges into pressure data of the deformation subchambers.
7. A rock-soil body mechanical parameter measuring system as claimed in claim 5, wherein, The circulation structure comprises a circulation pipeline, a plurality of through holes are distributed on the circulation pipeline, and the circulation pipeline is communicated with each deformation subchamber through the plurality of through holes.
8. A rock-soil body mechanical parameter measuring system as claimed in claim 1, wherein, The pressure control structure comprises a pressure control pipeline, a pressure reducing valve, a regulating valve and a pressure relief valve, wherein the pressure control pipeline is communicated with the pressure source and the deformation cavity, and the pressure reducing valve, the regulating valve and the pressure relief valve are arranged on the pressure control pipeline.
9. A rock-soil body mechanical parameter measuring system as claimed in claim 8, wherein, The pressure detection mechanism comprises a ground pressure detection structure, the ground pressure detection structure comprises an output pressure detection part, a low pressure detection part, a medium pressure detection part, a high pressure detection part and an input pressure detection part, the input pressure detection part is arranged at the input end of the pressure control pipeline, the output pressure detection part is arranged at the output section of the pressure control pipeline, and the low pressure detection part, the medium pressure detection part and the high pressure detection part are connected in parallel and arranged on the pressure control pipeline.
10. The method for measuring the mechanical parameters of the rock and soil mass is characterized by comprising the following steps of: implanting, namely implanting an elastic sleeve provided with a sensing optical cable into a rock-soil body, wherein the sensing optical cable is distributed along the axial direction of the elastic sleeve and is contacted with the elastic sleeve; loading, namely injecting pressure fluid into a deformation cavity of the elastic sleeve to expand the elastic sleeve; unloading, namely discharging the pressure fluid in the deformation cavity to retract the elastic sleeve; The data acquisition, namely, in the process of executing the loading step and in the process of unloading step, the pressure detection mechanism acquires the pressure data of the deformation cavity, and the optical fiber demodulator demodulates and processes the optical signal of the sensing optical cable into optical cable measurement data; And analyzing the data, namely analyzing and processing according to the pressure data and the optical fiber measurement data to obtain the mechanical parameters of the rock-soil body.
11. The method of claim 10, wherein the sensing fiber optic cable has a temperature sensing fiber and a strain sensing fiber, the fiber optic cable measurement data includes a temperature measurement and a strain measurement of the sensing fiber optic cable, the mechanical parameter includes a shear modulus of the rock mass, and the data analysis step specifically includes the steps of: generating circumferential strain of the elastic sleeve according to the temperature measurement result and the strain measurement result analysis and treatment; Drawing a pressure-circumferential strain curve from the circumferential strain and the pressure data; and selecting a linear section of the pressure-circumferential strain curve, and further calculating to obtain the shear modulus of the rock-soil body, wherein the shear modulus of the rock-soil body is the slope of the linear section.
12. The method of claim 11, wherein the mechanical parameters further comprise a deformation modulus of the rock mass, and wherein the data analyzing step further comprises generating the deformation modulus of the rock mass based on the shear modulus analysis.

Description

Rock-soil body mechanical parameter measurement system and method Technical Field The invention relates to the technical field of rock-soil mechanics, in particular to a system and a method for measuring rock-soil body mechanical parameters. Background The rock-soil body in-situ test technology refers to a technology for obtaining various mechanical parameters of a rock-soil body by performing a geotechnical test and a geotechnical mechanical test on a rock-soil body site, and is an important means for evaluating the mechanical properties of the rock-soil body and the quality of geotechnical engineering. The rock-soil body in-situ test technology comprises standard penetration, dynamic sounding, static sounding, ultrasonic waves, resistivity, stress wave measurement, foundation bearing capacity test, side pressure test and the like. Currently, the rock-soil body in-situ test technology still faces the common problems of insufficient precision, incomplete test indexes, higher cost, low test efficiency and the like. The side pressure test is a test method for the strength parameters of a commonly used rock-soil body. The basic principle is that side pressure is acted on the side surface of a test piece, and parameters such as compression modulus, shear strength and the like are calculated by measuring the deformation and the destabilizing force of the test piece. Since the advent of Meina bypass pressure instruments, the use of bypass pressure tests in rock and soil mass in situ testing has been very widespread. In the prior art, various modifications are performed on the Meina side pressure instrument according to the needs, but the side pressure test device and the test method obtained by the modifications still have various problems, such as the general problems of insufficient precision, incomplete test indexes, high cost, low test efficiency and the like, and the problems of poor mobility, strict requirements on the use environment and the like caused by various instrument parts. In addition, the existing single-cavity side compressor and multi-cavity side compressor still cannot concentrate on measuring the cross-horizon, and in addition, the difference of the rock and soil body strength at different positions around the hole wall at the same horizon cannot be revealed due to the fact that the whole volume change of the side compressor is measured. Among the most prominent problems is that the current test technology is difficult to achieve distributed measurement, and also instantaneous air-continuity measurement. In general, it is necessary to advance the test tool to one of the target horizons by various methods for measurement, take out the tool after the measurement is completed, and measure the next target horizon again. The point type measurement method is also difficult to provide permanent measurement, only data can be acquired once temporarily at regular or irregular periods, and historical dynamic evolution characteristics of the geologic body are difficult to reveal. However, many geological problems and engineering scenes have very high requirements on the space-time continuity measurement of the mechanical parameters of the rock and soil body, such as the problems of mechanical parameter change caused by fluid replacement in the geological storage or oil displacement process of carbon dioxide, mechanical parameter change of the foundation in the frost heaving and thawing process of seasonal frozen soil, and the like. Disclosure of Invention The invention aims to provide a rock-soil body mechanical parameter measurement system and a rock-soil body mechanical parameter measurement method, which are used for solving the technical problem that the distributed measurement of the rock-soil body mechanical parameter cannot be realized in the prior art. The above object of the present invention can be achieved by the following technical solutions: the invention provides a rock-soil body mechanical parameter measurement system which comprises an elastic sleeve, a sensing optical cable, an optical fiber demodulator, a pressure source, a pressure control structure and a data analysis mechanism, wherein the elastic sleeve is used for being implanted into a rock-soil body and is internally provided with a deformation cavity, the sensing optical cable is distributed along the axial direction of the elastic sleeve and is in contact with the elastic sleeve, the optical fiber demodulator is electrically connected with the sensing optical cable and can demodulate an optical signal of the sensing optical cable to generate optical cable measurement data, the pressure source is used for providing pressure fluid, the pressure control structure can be communicated with the deformation cavity through the pressure control structure, the pressure detection mechanism is used for collecting pressure data of the deformation cavity, and the data analysis mechanism is used for analyzing and processing according to the p