CN116907713A - Method for testing high ground stress of surrounding rock of deep-buried tunnel - Google Patents
Method for testing high ground stress of surrounding rock of deep-buried tunnel Download PDFInfo
- Publication number
- CN116907713A CN116907713A CN202310655859.5A CN202310655859A CN116907713A CN 116907713 A CN116907713 A CN 116907713A CN 202310655859 A CN202310655859 A CN 202310655859A CN 116907713 A CN116907713 A CN 116907713A
- Authority
- CN
- China
- Prior art keywords
- pressure
- measuring
- ground stress
- strength
- drilling
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000011435 rock Substances 0.000 title claims abstract description 78
- 238000012360 testing method Methods 0.000 title claims abstract description 53
- 238000000034 method Methods 0.000 title claims abstract description 39
- 238000005553 drilling Methods 0.000 claims abstract description 62
- 239000007788 liquid Substances 0.000 claims abstract description 54
- 230000005540 biological transmission Effects 0.000 claims abstract description 21
- 230000006835 compression Effects 0.000 claims abstract description 10
- 238000007906 compression Methods 0.000 claims abstract description 10
- 238000009662 stress testing Methods 0.000 claims abstract description 9
- 238000009434 installation Methods 0.000 claims abstract description 4
- 229910000831 Steel Inorganic materials 0.000 claims description 22
- 239000010959 steel Substances 0.000 claims description 22
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 20
- 238000002360 preparation method Methods 0.000 claims description 14
- 238000009530 blood pressure measurement Methods 0.000 claims description 8
- 230000005484 gravity Effects 0.000 claims description 8
- 239000003673 groundwater Substances 0.000 claims description 7
- 238000004364 calculation method Methods 0.000 claims description 6
- 239000000523 sample Substances 0.000 claims description 6
- 238000005259 measurement Methods 0.000 claims description 5
- 239000002184 metal Substances 0.000 claims description 3
- 238000009412 basement excavation Methods 0.000 abstract description 5
- 238000010276 construction Methods 0.000 abstract description 5
- 238000011161 development Methods 0.000 description 4
- 238000010586 diagram Methods 0.000 description 4
- 230000005251 gamma ray Effects 0.000 description 3
- 238000011065 in-situ storage Methods 0.000 description 3
- 241000282414 Homo sapiens Species 0.000 description 2
- 230000002411 adverse Effects 0.000 description 2
- 230000006378 damage Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000010998 test method Methods 0.000 description 2
- 208000011231 Crohn disease Diseases 0.000 description 1
- 239000004567 concrete Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 230000005489 elastic deformation Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000009440 infrastructure construction Methods 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 239000002689 soil Substances 0.000 description 1
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B49/00—Testing the nature of borehole walls; Formation testing; Methods or apparatus for obtaining samples of soil or well fluids, specially adapted to earth drilling or wells
- E21B49/006—Measuring wall stresses in the borehole
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L5/00—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/02—Details
- G01N3/06—Special adaptations of indicating or recording means
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/08—Investigating strength properties of solid materials by application of mechanical stress by applying steady tensile or compressive forces
- G01N3/10—Investigating strength properties of solid materials by application of mechanical stress by applying steady tensile or compressive forces generated by pneumatic or hydraulic pressure
- G01N3/12—Pressure testing
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/003—Generation of the force
- G01N2203/0042—Pneumatic or hydraulic means
- G01N2203/0048—Hydraulic means
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/0058—Kind of property studied
- G01N2203/0069—Fatigue, creep, strain-stress relations or elastic constants
- G01N2203/0075—Strain-stress relations or elastic constants
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/02—Details not specific for a particular testing method
- G01N2203/06—Indicating or recording means; Sensing means
- G01N2203/067—Parameter measured for estimating the property
- G01N2203/0676—Force, weight, load, energy, speed or acceleration
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/02—Details not specific for a particular testing method
- G01N2203/06—Indicating or recording means; Sensing means
- G01N2203/067—Parameter measured for estimating the property
- G01N2203/0682—Spatial dimension, e.g. length, area, angle
Landscapes
- Physics & Mathematics (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Physics & Mathematics (AREA)
- Pathology (AREA)
- Biochemistry (AREA)
- Geology (AREA)
- Mining & Mineral Resources (AREA)
- Immunology (AREA)
- General Health & Medical Sciences (AREA)
- Engineering & Computer Science (AREA)
- Health & Medical Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Fluid Mechanics (AREA)
- Geochemistry & Mineralogy (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Environmental & Geological Engineering (AREA)
- Force Measurement Appropriate To Specific Purposes (AREA)
- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
Abstract
The invention discloses a method for testing high ground stress of surrounding rock of a deep-buried tunnel. The method comprises the following steps: after drilling is completed, the installation connection and the lowering of all instruments and equipment in the high-ground stress testing device based on ultra-deep drilling are completed; step two: pressurizing by using pressurizing equipment to form high-strength liquid pressure, wherein the high-strength liquid pressure reaches a hole bottom piston through a flexible high-strength pressure transmission pipe, a pressure gauge and a built-in flexible high-strength pressure measuring pipe; step three: along with the pressure input of the pressurizing equipment, the flexible attaching plates at two sides of the piston are pressed and move laterally, are well attached to the wall of the drilling hole and gradually pressurize the wall of the drilling hole; step four: measuring the compression deformation of the rock mass on the inner wall of the drill hole after being pressed by a micrometer; step five: obtaining a P-s characteristic curve; step six: and obtaining the ground stress of the borehole wall rock mass test point. The invention has the advantage of measuring and judging the ground stress before the deep underground cavity or tunnel excavation construction.
Description
Technical Field
The invention relates to a method for testing high ground stress of surrounding rock of a deep-buried tunnel.
Background
The undisturbed stresses stored inside the rock mass are called ground stresses, which can be divided into two categories, in-situ stresses and induced stresses, whereas in-situ stresses come mainly from five aspects: the dead weight of the rock mass, the geological structure activity, the universal gravitation, the sealing stress and the external load. The ground stress has multiple origins and is influenced by various factors, so the ground stress distribution of the crust rock mass is complex and changeable. The need for social development has directly led to a number of ground stress testing and estimation methods, and the development of these methods has further promoted the infrastructure construction, resource and energy development of the human society. Along with the increase of the energy, mineral, hydroelectric and other resource demands of human beings and the continuous increase of the exploitation intensity, the exploitation at home and abroad sequentially enters a deep resource exploitation state, and the three-high problem (high ground stress, high ground temperature and high water pressure) encountered in the deep exploitation becomes a focus and difficulty problem in the study of the rock mechanics of a deep-buried tunnel (channel) or a large underground cavity. Accurate determination of in-situ stress conditions in deep development space areas is one of the necessary ways to solve the above problems, which requires research on ground stress testing methods and techniques.
Practice shows that rock mass excavation work performed during construction of earth surface and underground engineering in high stress areas can often cause a series of deformation and damage phenomena associated with unloading rebound and stress release in the rock mass, and as a result, not only the engineering geological conditions of the foundation or side slope rock mass can be deteriorated, but also the action itself can sometimes cause direct harm to the building.
High ground stress is distributed in surrounding rock bodies of a deep-buried tunnel (channel) or a large-scale underground cavity, adverse working conditions such as rock burst and the like are easy to generate, the stability of surrounding rock of the underground cavity is adverse, and the accurate and effective means for testing the ground stress are mainly implemented on a working surface after the cavity is excavated to form the working surface, so that the mode has certain hysteresis and limitation. Therefore, the early determination of the deep high ground stress is very important.
Therefore, it is necessary to develop a test method capable of measuring and determining the ground stress by using the pre-ultra-deep exploration drilling before the excavation construction of the deep buried underground cavern or tunnel.
Disclosure of Invention
The invention aims to overcome the defects of the background technology, and provides a method for testing the high ground stress of surrounding rock of a deep-buried tunnel, which is used for measuring and judging the high ground stress of the surrounding rock before the construction of the deep-buried tunnel (tunnel) or a large-scale underground cavity, and simultaneously, the drilling coring of an ultra-deep exploration drilling hole is adopted to obtain stratum information, and meanwhile, other proper equipment or instruments are adopted to test in the ultra-deep exploration drilling hole to obtain the ground stress information of a deep horizon, so that the preliminary judgment on whether the high ground stress exists is carried out, and the method is economical, practical, quick and efficient; the method solves the problems that surrounding rocks of a deep buried tunnel (channel) or a large underground cavity in the prior art are mostly accompanied with high ground stress distribution, a certain working surface is formed by excavation of the cavity, and then the working surface is tested, so that the method has certain hysteresis and limitation.
In order to achieve the above purpose, the technical scheme of the invention is as follows: a method for testing high ground stress of surrounding rock of a deeply buried tunnel is characterized by comprising the following steps of: comprises the following steps of the method,
step one: after drilling is completed, the installation connection and the lowering of all instruments and equipment in the high-ground stress testing device based on ultra-deep drilling are completed;
step two: pressurizing by using pressurizing equipment to form high-strength liquid pressure, wherein the high-strength liquid pressure reaches a hole bottom piston through a flexible high-strength pressure transmission pipe, a pressure gauge and a built-in flexible high-strength pressure measuring pipe; wherein the pressure gauge is used for measuring the applied pressure;
step three: along with the pressure input of the pressurizing equipment, the flexible attaching plates at two sides of the piston are pressed and move laterally, are well attached to the wall of the drilling hole and gradually pressurize the wall of the drilling hole;
step four: measuring the compression deformation of the rock mass on the inner wall of the drill hole after being pressed by a micrometer;
step five: obtaining a P-s characteristic curve;
along with the increasing of the pressurization equipment, the pressure applied by the flexible laminated plate to the hole wall is gradually increased, the increasing trend of the load pressure P is larger and larger, namely delta P/delta s is larger and larger, wherein the deformation s of the hole wall rock mass in the drilling hole tends to a certain specific value; when the load pressure P is increased, the micro deformation increment of the corresponding borehole inner wall rock mass is relatively reduced, and a P-s characteristic curve is recorded and obtained;
step six: obtaining the ground stress of a rock mass test point of the inner hole wall of the drill hole;
to obtain a proper pressure characteristic value P 0 The corresponding compressive stress p is the ground stress of the rock mass test point of the inner hole wall of the drilling hole.
In the above technical solution, in the fourth step, the specific method for measuring the compression deformation of the borehole inner hole wall rock mass after being pressed by the micrometer includes:
1) Positioning a ball cone, and measuring marks with a spherical top end and an annular cone shape of the probe, so as to ensure that the length of the probe is 1m during measurement;
2) A metal measuring mark is arranged on the plastic sleeve at intervals of each meter, the measuring line is divided into a plurality of sections, the measuring mark and a measured medium are firmly poured together through grouting, and when the rock mass on the inner wall of the drill hole deforms, the measuring mark is driven to synchronously deform with the rock mass; and (3) measuring the change of each gauge length along time segment by using a sliding micrometer, thereby obtaining the deformation distribution rule reflecting the rock mass of the inner hole wall of the drill hole along the measuring line.
In the above technical solution, in the fifth step, the specific value is the unloading rebound deformation s of the rock mass 0 。
In the above technical solution, in the sixth step, the method for testing the ground stress of the rock mass test point of the borehole inner hole wall comprises:
for the value of the ground stress p, firstly, taking Deltas/b or Deltas/d equal to 0.005 value according to the characteristic point E measured by the residual relative deformation, wherein Deltas is the residual deformation, namely Deltas=s 0 S', b is the side length when the flexible bonding plate takes a square shape, and d is the diameter when the flexible bonding plate takes a circular shape;
then, a tangent line of the P-s characteristic curve is made through the corresponding characteristic point E, and a characteristic point F is obtained;
taking the pressure value P corresponding to the F point 0 The pressure is the pressure of the test point, and the corresponding compressive stress p is the ground stress of the rock mass test point of the inner hole wall of the drill hole;
the borehole 8 includes a waterless borehole and a watered borehole;
when the drilling is anhydrous drilling, the calculation method of the ground stress of the rock mass test point of the inner hole wall of the drilling comprises the following steps:
p＝P 0 and/A, while the compressive stress p is converted by:
p＝p p +p z
p z ＝γ liquid and its preparation method ×h z
Wherein: a is the area of the flexible bonding pressure plate;
p p for the manometer reading;
p z the liquid column pressure from the center of the pressure gauge to the measuring point is set;
γ liquid and its preparation method Is the gravity of the pressurized liquid;
h z the height of the pressurized liquid column from the center of the pressure gauge at the top of the pressure measuring pipe to the measuring point is set;
when the drilling is water drilling, the calculation method of the ground stress of the rock mass test point of the inner hole wall of the drilling comprises the following steps:
p＝(P 0 -P w ) A, wherein P w ＝p w X a, while the compressive stress p can be converted by:
p＝p p +p z -p w
p z ＝γ liquid and its preparation method ×h z
p w ＝γ w ×h w
Wherein: a is the area of the flexible bonding pressure plate;
p p for the manometer reading;
p z the liquid column pressure from the center of the pressure gauge to the measuring point is set;
P w the original water pressure in the drill hole is obtained;
γ liquid and its preparation method Is the gravity of the pressurized liquid;
γ w is the underground water weight in the ultra-deep drilling hole;
h z the height of the pressurized liquid column from the center of the pressure gauge at the top of the pressure measuring pipe to the measuring point is set;
h w is the height from the ground water level to the measuring point in the ultra-deep drilling hole.
In the technical scheme, the high ground stress testing device based on ultra-deep drilling comprises pressurizing equipment, a flexible high-strength pressure transmission pipe, a pressure gauge, a flexible high-strength pressure measurement pipe, a hollow steel pipe, a piston, a micrometer and an orifice fixing device;
the orifice fixing device is positioned at the upper end of the drilling hole;
the flexible high-strength piezometer tube is positioned in the drill hole; the upper end of the flexible high-strength pressure measuring tube is fixed on the orifice fixing device and extends upwards out of the orifice fixing device to be connected with the flexible high-strength pressure transmission tube; the lower end of the flexible high-strength pressure measuring tube is provided with a piston; the micrometer is arranged in the piston;
the flexible high-strength pressure transmission pipe is connected with the pressurizing equipment;
the pressure gauge is positioned on the flexible high-strength pressure transmission pipe and is connected with the flexible high-strength pressure measurement pipe;
the hollow steel pipe is sleeved on the periphery of the flexible high-strength pressure measuring pipe;
a flexible bonding plate is arranged on the side of the piston.
In the technical scheme, the piston is in a linear or cross-shaped structure;
the micrometer is a sliding micrometer;
the micrometer is arranged in the linear or cross-shaped piston at the bottom of the hole; the cross-shaped pistons are arranged perpendicular to the axis of the cavity and parallel to the axis of the cavity.
In the above technical solution, the micrometer is a microscope micrometer.
The invention has the following advantages:
(1) The method can measure and judge the ground stress before the excavation construction of the deep underground cavern or tunnel (or the deep bedrock, the depth of the deep bedrock is more than (2-2.5) hq, wherein hq represents the equivalent height of the load), can be used as an effective means for measuring the ground stress in the early stage and initially judging whether the high ground stress exists, and is economical, practical, rapid and efficient;
(2) The pressurizing device can provide liquid high pressure; the pressure gauge on the flexible high-strength pressure transmission pipe is arranged on the flexible high-strength pressure measurement pipe, so that the size of the transmitted high-pressure can be directly measured; the built-in flexible high-strength pressure measuring tube can convey liquid high pressure to the piston at the bottom of a hole, the hollow steel tube sleeved outside the hollow steel tube can be divided into a plurality of sections which are mutually connected and lowered to the bottom of the hole, meanwhile, the built-in flexible high-strength pressure measuring tube is protected, the flexible bonding plate which is connected and fixed with the lower piston is used for bearing high-strength liquid pressure in the piston and can laterally move under pressure, pressure is applied to the wall of a drilling hole, a micrometer is arranged in the piston and used for cooperatively measuring the compression deformation of the wall of the hole after being pressed, and the orifice fixing device is used for guaranteeing the lowering and fixing of equipment such as the hollow steel tube, the flexible high-strength pressure measuring tube, the piston and the like.
Drawings
FIG. 1 is a cross-sectional view and layout of a straight piston in the present invention.
Fig. 2 is a cross-shaped piston cross-sectional configuration and layout of the present invention.
FIG. 3 is a graph of P-s characteristics of the present invention during an in-hole anhydrous test.
FIG. 4 is a graph of P-s characteristics of the present invention during a test with water in the well.
FIG. 5 is a schematic diagram of the experimental procedure of the present invention in the absence of water in the well.
FIG. 6 is a schematic diagram showing the structure of the test procedure of the present invention when water is present in the well.
Fig. 7 is a schematic diagram of a working structure of the present invention for performing stress test by using a high ground stress test device based on ultra-deep drilling.
Fig. 8 is a schematic view of the structure of an underground cavern or tunnel in the present invention.
Fig. 9 is a process flow diagram of the present invention.
In fig. 3 and 4, E, F each represents a different feature point; s' represents the deformation amount of the feature point E; s is(s) 0 Representing the deformation of the feature point F; p (P) 0 The pressure of the test point (also the pressure of the characteristic point F); p' represents the pressure of the feature point E;
in FIG. 4, P w The original water pressure in the drill hole is obtained;
in FIG. 5, p p For the manometer reading; p is p z The liquid column pressure from the center of the pressure gauge to the measuring point is set; h is a z The height of the pressurized liquid column from the center of the pressure gauge at the top of the pressure measuring pipe to the measuring point is set; gamma ray Liquid and its preparation method Is the gravity of the pressurized liquid;
in fig. 6, A3 represents a groundwater level; p is p p For the manometer reading; p is p z The liquid column pressure from the center of the pressure gauge to the measuring point is set; h is a z The height of the pressurized liquid column from the center of the pressure gauge at the top of the pressure measuring pipe to the measuring point is set; gamma ray Liquid and its preparation method Is the gravity of the pressurized liquid; p (P) w The original water pressure in the drill hole is obtained; h is a w The height from the ground water level in the ultra-deep borehole to the measuring point; gamma ray w Is the underground water weight in the ultra-deep drilling hole;
in fig. 6, 0 s on both sides of the groundwater level represent groundwater level values.
In fig. 8, A1 represents an axis; a2 represents an underground cavern or tunnel.
In the figure, 1-pressurizing equipment, 2-flexible high-strength pressure transmission pipe, 3-manometer, 4-flexible high-strength pressure measurement pipe, 5-hollow steel pipe, 5.1-hollow steel pipe section, 6-piston, 7-micrometer, 8-drilling hole, 8.1-drilling hole wall, 9-orifice fixing device and 10-flexible bonding plate.
Detailed Description
The following detailed description of the invention is, therefore, not to be taken in a limiting sense, but is made merely by way of example. While making the advantages of the present invention clearer and more readily understood by way of illustration.
As can be seen with reference to the accompanying drawings: a method for testing the high ground stress of surrounding rock of a deeply buried tunnel comprises the following steps,
step one: after the drilling 8 is completed, the installation connection and the lowering of each instrument and equipment in the high-ground stress testing device based on ultra-deep drilling are completed (as shown in fig. 7);
step two: the pressurizing equipment 1 pressurizes to form high-strength liquid pressure, and the high-strength liquid pressure reaches the hole bottom piston 6 through the flexible high-strength pressure transmission pipe 2, the pressure gauge 3 and the built-in flexible high-strength pressure measuring pipe 4; wherein the pressure gauge 3 is used for measuring the applied pressure;
step three: along with the pressure input of the pressurizing equipment 1, the flexible bonding plates 10 at the two sides of the piston 6 are pressed and move laterally, are well bonded with the borehole wall 8.1 and gradually pressurize the borehole wall;
step four: measuring the compression deformation of the rock mass on the inner wall of the drill hole after being pressed by a micrometer 7;
step five: obtaining a P-s characteristic curve;
as the pressurization of the pressurization device 1 increases, the pressure applied by the flexible bonding sheet 10 to the hole wall gradually increases;
when high ground stress exists in the ultra-deep drilling hole, after the drilling hole is drilled and coring, when the lithology of hard rock is single and the texture is uniform, corresponding unloading rebound micro-deformation occurs to the wall rock of the drilling hole along with high ground stress release, the micro-deformation is mainly elastic deformation, when a certain measure is taken for applying radial load to the wall of the drilling hole in a certain area, the deformation of the unloading rebound of the rock mass is gradually reduced along with load increase and stress increase until the unloading rebound deformation completely counteracts, and even the compression deformation of the rock mass occurs.
In the loading process, along with the gradual counteraction of the unloading rebound deformation, the increasing trend of the load pressure P is larger and larger, namely delta P/delta s is larger and larger, wherein the deformation s of the rock mass of the inner hole wall of the drill hole tends to a certain specific value (namely the unloading rebound deformation s of the rock mass 0 ) The method comprises the steps of carrying out a first treatment on the surface of the When the load pressure P is increased, the micro deformation increment of the corresponding borehole inner wall rock mass is relatively reduced, and a P-s characteristic curve is recorded and obtained; the P-s characteristic curve graph of the invention in the test process when no water exists in the hole is shown in figure 3; the characteristic curve graphs of P-s in the test process of the invention when water exists in the hole are shown in figure 4;
step six: obtaining the ground stress of a rock mass test point of the inner hole wall of the drill hole;
can calculate a proper pressure characteristic value P 0 The corresponding compressive stress p is the ground stress of the rock mass test point of the inner hole wall of the drill hole (as shown in fig. 9).
Further, in the fourth step, the specific method for measuring the compression deformation of the rock mass of the inner hole wall of the drill hole by the micrometer comprises the following steps:
1) Positioning a ball cone, and measuring marks with a spherical top end and an annular cone shape of the probe, so as to ensure that the length of the probe is 1m during measurement;
2) A metal measuring mark is arranged on the plastic sleeve at intervals of each meter, the measuring line is divided into a plurality of sections, the measuring mark and a measured medium are firmly poured together through grouting, and when the rock mass on the inner wall of the drill hole deforms, the measuring mark is driven to synchronously deform with the rock mass; and (3) measuring the change of each gauge length along time segment by using a sliding micrometer, thereby obtaining the deformation distribution rule reflecting the rock mass of the inner hole wall of the drill hole along the measuring line.
Further, in the fifth step, the specific value is the unloading rebound deformation s of the rock mass 0 。
Further, in the step six, the method for testing the ground stress of the rock mass test point of the inner hole wall of the drill hole comprises the following steps:
for the value of the ground stress p, firstly, taking Deltas/b or Deltas/d equal to 0.005 value according to the characteristic point E measured by the residual relative deformation, wherein Deltas is the residual deformation, namely Deltas=s 0 S' when flexibly fittingB is the side length when the board takes a square shape, and d is the diameter when the flexible bonding board is circular;
then, a tangent line of the P-s characteristic curve is made through the corresponding characteristic point E, and a characteristic point F is obtained;
taking the pressure value P corresponding to the F point 0 The pressure is the pressure of the test point, and the corresponding compressive stress p is the ground stress of the rock mass test point of the inner hole wall of the drill hole;
the borehole 8 includes a waterless borehole and a watered borehole;
when the drilling is anhydrous drilling, the calculation method of the ground stress of the rock mass test point of the inner hole wall of the drilling comprises the following steps:
p＝P 0 and/a, while the compressive stress p can be converted by the following formula (as shown in fig. 5):
p＝p p +p z
p z ＝γ liquid and its preparation method ×h z
Wherein: a is the area of the flexible bonding pressure plate;
p p reading for a manometer (manometer mounted on a pressure tube);
p z the liquid column pressure (compressive stress) from the center of the pressure gauge to the measuring point;
γ liquid and its preparation method Is the gravity of the pressurized liquid;
h z the height of the pressurized liquid column from the center of the pressure gauge at the top of the pressure measuring pipe to the measuring point is measured.
When the drill hole is a water drill hole, a certain initial water pressure P exists w Therefore, to make the flexible bonding plates at two sides of the piston well bonded with the hole wall, the initial water pressure P should be overcome w At this time, the calculation method of the ground stress of the rock mass test point of the inner hole wall of the drill hole comprises the following steps:
p＝(P 0 -P w ) A, wherein P w ＝p w X a, while the compressive stress p can be converted by the following formula (as shown in fig. 6):
p＝p p +p z -p w
p z ＝γ liquid and its preparation method ×h z
p w ＝γ w ×h w
Wherein: a is the area of the flexible bonding pressure plate;
p p reading for a manometer (manometer mounted on a pressure tube);
p z the liquid column pressure (compressive stress) from the center of the pressure gauge to the measuring point;
P w is the original water pressure (compressive stress) in the borehole;
γ liquid and its preparation method Is the gravity of the pressurized liquid;
γ w is the underground water weight in the ultra-deep drilling hole;
h z the height of the pressurized liquid column from the center of the pressure gauge at the top of the pressure measuring pipe to the measuring point is set;
h w is the height from the ground water level to the measuring point in the ultra-deep drilling hole.
Further, the high ground stress testing device based on ultra-deep drilling comprises a pressurizing device 1, a flexible high-strength pressure transmission pipe 2, a pressure gauge 3, a flexible high-strength pressure measurement pipe 4, a hollow steel pipe 5, a piston 6, a micrometer 7 and an orifice fixing device 9;
the orifice fixing device 9 is positioned at the upper end of the drilling hole 8, and the orifice fixing device 9 is used for guaranteeing the descending and fixing of the hollow test steel tube 5, the flexible high-strength pressure measuring tube 4, the piston 6 and other equipment;
the borehole wall 8.1 is straight and smooth, so that the integrity of coring of the test section is ensured;
the flexible high-strength piezometer tube 4 is positioned in the drill hole 8; a piston 6 which is internally provided with a flexible high-strength pressure measuring tube 4 and used for conveying liquid high pressure to the bottom of a drilling hole;
the upper end of the flexible high-strength pressure measuring tube 4 is fixed on the orifice fixing device 9, and extends out of the orifice fixing device 9 upwards to be connected with the flexible high-strength pressure transmission tube 2; the lower end of the flexible high-strength pressure measuring tube 4 is provided with a piston 6, the interior of the piston 6 bears the high-strength liquid pressure conveyed by the flexible high-strength pressure measuring tube 4, and the lateral direction is a flexible bonding plate which can move laterally under pressure, so as to apply pressure to the wall 8.1 of the drilling hole;
the micrometer 7 is arranged in the piston 6 and is used for cooperatively measuring the compression deformation of the hole wall after being pressed, and belongs to micro deformation;
the flexible high-strength pressure transmission pipe 2 is connected with the pressurizing equipment 1; the pressurizing device 1 transmits liquid high pressure to the piston 6 through the flexible high-strength pressure transmission pipe 2;
the pressure gauge 3 is positioned on the flexible high-strength pressure transmission pipe 2 and is connected with the flexible high-strength pressure measurement pipe 4, so that the high-pressure transmitted by the flexible high-strength pressure transmission pipe 2 can be directly measured;
the hollow steel pipe 5 is sleeved on the periphery of the flexible high-strength pressure measuring pipe 4 and is positioned above the piston 6;
the flexible veneer sheet 10 is arranged on the side of the piston 6, when the inside of the piston 6 bears the high-strength liquid pressure conveyed by the flexible high-strength pressure measuring pipe 4, the flexible veneer sheet 10 is pressed and moves laterally, and pressure is applied to the wall of a drilling hole. The flexible bonding plate 10 has higher strength and can be well bonded with the wall of a drilling hole under the condition of being pressed; along with the external liquid high pressure input bottom piston (hollow steel tube sleeved outside the drill hole lowering section, hollow steel tube plays a role of fixing the lower piston to control the piston direction and protect the flexible high-strength pressure measuring tube) through the flexible high-strength pressure transmission tube and the pressure measuring tube, along with the movement of flexible bonding plates at two sides of the piston to the hole wall until the flexible bonding plates are well bonded with the hole wall, the micrometer 7 starts to measure the change of pressure and deformation, and along with the increase of pressure, the deformation of the rock mass of the hole wall in the drill hole is gradually increased until the unloading rebound deformation of the rock mass is basically counteracted.
Further, the piston 6 is in a straight-line or cross-shaped structure, and the straight-line or cross-shaped piston is relatively more suitable for uniformity and stability of pressurization stress;
the micrometer is a sliding micrometer;
the micrometer is arranged in the linear or cross-shaped piston at the bottom of the hole; the micrometer orientations were arranged in the test corresponding to the axes of an underground cavern or tunnel (as shown in fig. 8), wherein the in-line pistons 6 were arranged perpendicular to the cavern axis (as shown in fig. 1), and the cross-shaped pistons 6 were arranged perpendicular to and parallel to the cavern axis (as shown in fig. 2).
Further, the micrometer 7 is a microscope micrometer, and in the whole test process, the deformation is mostly micro deformation, so that the measurement of micro deformation is extremely critical, and the micrometer with relatively good quality and performance is needed to be used for measurement, for example, a microscope micrometer (device) is used. The micrometer has high test precision, and can be used for measuring axial displacement of a drilling hole in any direction and a measuring line in rock, concrete or soil with high precision, such as a KEYENCE Crohn's ultra-high speed/high precision micrometer LS-9000 series.
Furthermore, the lower end of the hollow steel pipe 5 is positioned at the bottom of the drilling hole, so as to play a role in protecting the built-in flexible high-strength pressure measuring pipe;
the piston 6 is connected at the lower extreme of cavity steel pipe 5, and cavity steel pipe plays the effect of linking fixed lower part piston.
Further, the hollow steel pipe 5 comprises a plurality of hollow steel pipe sections 5.1, the hollow steel pipe sections 5.1 are longitudinally connected, and the hollow steel pipe is divided into a plurality of sections which are mutually connected and lowered to the bottom of the hole, and meanwhile, the hollow steel pipe plays a role in protecting the built-in flexible high-strength pressure measuring pipe and connecting and fixing the lower piston.
Other non-illustrated parts are known in the art.
Claims (7)
1. A method for testing high ground stress of surrounding rock of a deeply buried tunnel is characterized by comprising the following steps of: comprises the following steps of the method,
step one: after the drilling (8) is finished, the installation connection and the lowering of all instruments and equipment in the high-ground stress testing device based on ultra-deep drilling are finished;
step two: the pressurizing device (1) pressurizes to form high-strength liquid pressure, and the high-strength liquid pressure reaches the hole bottom piston (6) through the flexible high-strength pressure transmission pipe (2), the pressure gauge (3) and the built-in flexible high-strength pressure measuring pipe (4); wherein the pressure gauge (3) is used for measuring the applied pressure;
step three: along with the pressure input of the pressurizing equipment (1), the flexible bonding plates (10) at the two sides of the piston (6) are pressed and move laterally, are well bonded with the borehole wall (8.1) and gradually press the borehole wall;
step four: measuring the compression deformation of the rock mass of the inner hole wall of the drill hole after being pressed by a micrometer (7);
step five: obtaining a P-s characteristic curve;
as the pressurizing of the pressurizing equipment (1) is increased, the pressure applied by the flexible bonding plate (10) to the hole wall is gradually increased, the increasing trend of the load pressure P is larger and larger, namely deltaP/deltas is larger and larger, wherein the deformation s of the hole wall rock mass in the drilling hole tends to a certain specific value; when the load pressure P is increased, the micro deformation increment of the corresponding borehole inner wall rock mass is relatively reduced, and a P-s characteristic curve is recorded and obtained;
step six: obtaining the ground stress of a rock mass test point of the inner hole wall of the drill hole;
obtaining a certain pressure characteristic value P 0 The corresponding compressive stress p is the ground stress of the rock mass test point of the inner hole wall of the drilling hole.
2. The method for testing the high ground stress of the surrounding rock of the deeply buried tunnel according to claim 1, which is characterized by comprising the following steps: in the fourth step, the specific method for measuring the compression deformation of the rock mass of the inner hole wall of the drill hole by the micrometer comprises the following steps:
1) Positioning a ball cone, and measuring marks with a spherical top end and an annular cone shape of the probe, so as to ensure that the length of the probe is 1m during measurement;
2) A metal measuring mark is arranged on the plastic sleeve at intervals of each meter, the measuring line is divided into a plurality of sections, the measuring mark and a measured medium are firmly poured together through grouting, and when the rock mass on the inner wall of the drill hole deforms, the measuring mark is driven to synchronously deform with the rock mass; and (3) measuring the change of each gauge length along time segment by using a sliding micrometer, thereby obtaining the deformation distribution rule reflecting the rock mass of the inner hole wall of the drill hole along the measuring line.
3. The method for testing the high ground stress of the surrounding rock of the deeply buried tunnel according to claim 1 or 2, wherein the method comprises the following steps of: in the fifth step, the specific value is the unloading rebound deformation s of the rock mass 0 。
4. The method for testing the high ground stress of the surrounding rock of the deeply buried tunnel according to claim 3, wherein the method comprises the following steps of: in the sixth step, the method for testing the ground stress of the rock mass test point of the inner hole wall of the drill hole comprises the following steps:
for the value of the ground stress p, firstly, taking deltas/b or deltas/d equal to 0.005 value according to the characteristic point E measured by the residual relative deformation, wherein deltas is the residual deformation, namely deltas=s 0 S', b is the side length when the flexible bonding plate takes a square shape, and d is the diameter when the flexible bonding plate takes a circular shape;
then, a tangent line of the P-s characteristic curve is made through the corresponding characteristic point E, and a characteristic point F is obtained;
taking the pressure value P corresponding to the F point 0 The pressure is the pressure of the test point, and the corresponding compressive stress p is the ground stress of the rock mass test point of the inner hole wall of the drill hole;
the borehole 8 includes a waterless borehole and a watered borehole;
when the drilling is anhydrous drilling, the calculation method of the ground stress of the rock mass test point of the inner hole wall of the drilling comprises the following steps:
p＝P 0 and/A, while the compressive stress p is converted by:
p＝p p +p z
p z ＝γ liquid and its preparation method ×h z
Wherein: a is the area of the flexible bonding pressure plate;
p p for the manometer reading;
p z the liquid column pressure from the center of the pressure gauge to the measuring point is set;
γ liquid and its preparation method Is the gravity of the pressurized liquid;
h z the height of the pressurized liquid column from the center of the pressure gauge at the top of the pressure measuring pipe to the measuring point is set;
when the drilling is water drilling, the calculation method of the ground stress of the rock mass test point of the inner hole wall of the drilling comprises the following steps:
p＝(P 0 -P w ) A, wherein P w ＝p w X a, while the compressive stress p is converted by:
p＝p p +p z -p w
p z ＝γ liquid and its preparation method ×h z
p w ＝γ w ×h w
Wherein: a is the area of the flexible bonding pressure plate;
p p for the manometer reading;
p z the liquid column pressure from the center of the pressure gauge to the measuring point is set;
P w the original water pressure in the drill hole is obtained;
γ liquid and its preparation method Is the gravity of the pressurized liquid;
γ w is the underground water weight in the ultra-deep drilling hole;
h z the height of the pressurized liquid column from the center of the pressure gauge at the top of the pressure measuring pipe to the measuring point is set;
h w is the height from the ground water level to the measuring point in the ultra-deep drilling hole.
5. The method for testing the high ground stress of the surrounding rock of the deeply buried tunnel according to claim 4, which is characterized by comprising the following steps: the high ground stress testing device based on ultra-deep drilling comprises a pressurizing device (1), a flexible high-strength pressure transmission pipe (2), a pressure gauge (3), a flexible high-strength pressure measurement pipe (4), a hollow steel pipe (5), a piston (6), a micrometer (7) and an orifice fixing device (9);
the orifice fixing device (9) is positioned at the upper end of the drilling hole;
the flexible high-strength piezometer tube (4) is positioned in the drill hole; the upper end of the flexible high-strength pressure measuring tube (4) is fixed on the orifice fixing device (9), and extends out of the orifice fixing device (9) upwards to be connected with the flexible high-strength pressure transmission tube (2); the lower end of the flexible high-strength piezometer tube (4) is provided with a piston (6); the micrometer (7) is arranged in the piston (6);
the flexible high-strength pressure transmission pipe (2) is connected with the pressurizing equipment (1);
the pressure gauge (3) is positioned on the flexible high-strength pressure transmission pipe (2) and is connected with the flexible high-strength pressure measurement pipe (4);
the hollow steel tube (5) is sleeved on the periphery of the flexible high-strength pressure measuring tube (4);
a flexible bonding plate (10) is arranged on the lateral side of the piston (6).
6. The method for testing the high ground stress of the surrounding rock of the deeply buried tunnel according to claim 5, which is characterized by comprising the following steps: the piston (6) is in a straight or cross structure;
the micrometer is a sliding micrometer;
the micrometer is arranged in the linear or cross-shaped piston at the bottom of the hole; the straight-shaped pistons (6) are arranged perpendicular to the axis of the cavity, and the cross-shaped pistons (6) are arranged perpendicular to the axis of the cavity and parallel to the axis of the cavity.
7. The method for testing the high ground stress of the surrounding rock of the deeply buried tunnel according to claim 6, which is characterized by comprising the following steps: the micrometer (7) is a microscope micrometer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310655859.5A CN116907713A (en) | 2023-06-05 | 2023-06-05 | Method for testing high ground stress of surrounding rock of deep-buried tunnel |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310655859.5A CN116907713A (en) | 2023-06-05 | 2023-06-05 | Method for testing high ground stress of surrounding rock of deep-buried tunnel |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116907713A true CN116907713A (en) | 2023-10-20 |
Family
ID=88350021
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310655859.5A Pending CN116907713A (en) | 2023-06-05 | 2023-06-05 | Method for testing high ground stress of surrounding rock of deep-buried tunnel |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116907713A (en) |
-
2023
- 2023-06-05 CN CN202310655859.5A patent/CN116907713A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108872530B (en) | Large-scale model test device for simulating asymmetric small-clear-distance tunnel excavation process | |
| Marsland et al. | Comparisons of the results from pressuremeter tests and large in situ plate tests in London Clay | |
| CN105181199B (en) | A kind of side hole stress relief method of detecting earth stress | |
| JP6112663B2 (en) | In-situ rock test method and test equipment | |
| CN101638902B (en) | Method for measuring pile shaft internal force and cross section displacement in vertical dead-load test of foundation pile | |
| CN103076245B (en) | Method for measuring change law and values of deep-buried hard rock mechanical parameters | |
| CN108301828B (en) | Ground stress testing device and method based on deep drilling aperture deformation measurement | |
| CN212514040U (en) | Capsule pressure testing device | |
| CN105181190A (en) | Device for testing mechanical characteristic of tunnel locking anchor pipe and testing method for device | |
| CN114813371B (en) | Method for determining damage partition and height of overlying strata based on permeation-damage relationship | |
| CN106769501A (en) | A kind of measuring method of the Deformation Module of Rock Mass of different depth | |
| CN110967252A (en) | Device for simulating influence of shield tunnel construction on existing tunnel and using method thereof | |
| CN112781765A (en) | Novel simple ground stress testing device and testing method | |
| CN105952445B (en) | A kind of boring test method under large ground pressure based on mathematical model | |
| CN102808429B (en) | Pile foundation soaking load test method based on creep-strain separation | |
| CN109488331B (en) | Molded shield tunnel segment and stress test method thereof | |
| Zhao et al. | Review of geomechanical similar-material test systems | |
| CN113931239A (en) | Device and method for detecting quality of pile body of bridge squeezing and expanding supporting disc pile | |
| CN220690321U (en) | High ground stress testing device based on ultra-deep drilling | |
| CN116907713A (en) | Method for testing high ground stress of surrounding rock of deep-buried tunnel | |
| Singh et al. | Deformability of Rock Mass by Different Methods Inside Underground Desilting Chamber | |
| CN116625566A (en) | Continuous measuring method for real three-dimensional stress of engineering rock mass | |
| CN103835319B (en) | The real stake test method of on-the-spot Observable under concrete expansion dish demifacet stake pressured state | |
| Charsley et al. | Sleeve-fracturing limitations for measuring in situ stress in an anisotropic stress environment | |
| CN113834731A (en) | Experiment system and method for in-situ measurement of elastic modulus and shear strength of rock mass |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |