Deep rock mass strength in-hole and out-hole combined drilling testing equipment and testing method

Abstract

The present invention discloses a deep rock mass strength in-hole and out-hole combined drilling test equipment and a test method thereof, wherein the deep rock mass strength in-hole and out-hole combined drilling test equipment comprises a drilling rig, an out-hole drilling parameter test unit, a drill rod, an in-hole rock strength test unit, a hole surface seismic wave detector, a laser rangefinder, a control processing unit and an external drilling device. The present invention realizes the identification of discrete rock strength, continuous rock strength, rock mass longitudinal wave velocity and rock mass structural surface respectively through in-hole, out-hole and hole surface drilling tests, and calculates rock mass strength parameters through rock mass structural surface and rock strength information, which can be used for drilling while measuring the rock mass strength parameters actually drilled by the drill bit, which helps to improve the accuracy of deep underground engineering surveys and provide reliable geological data for engineering disaster risk assessment and support design and construction.

Description

Technical Field

[0001] The invention relates to the technical field of rock mass exploration, in particular to a deep rock mass strength inside-outside-hole combined while-drilling testing device and a deep rock mass strength inside-outside-hole combined while-drilling testing method. Background Art

[0002] In many fields such as mining engineering, water conservancy and water construction, tunnel transportation and slope engineering, with rock as the main research object, in-situ identification of rock types, structural characteristics and rock quality evaluation is crucial. These tasks are necessary steps in construction scheme selection, structural design and slope support. However, due to the lack of sufficient geological structure and rock mass parameters in many projects, it may lead to construction delays, economic losses, and even cause dynamic disasters such as rock bursts and collapses, causing heavy losses. Therefore, seeking safe, economical and efficient methods to obtain rock mass characteristics has always been the goal pursued by geotechnical engineering practitioners.

[0003] Taking into account that all types of geotechnical engineering involve drilling processes, some scholars have proposed a drilling method based on measurement while drilling technology. This method monitors, records and extracts effective information during the drilling process to make preliminary judgments on the drilled stratum structure and rock properties. It effectively solves the problems of traditional exploration methods such as difficulty in coring, poor timeliness and limited usage scenarios, and has therefore received widespread attention.

[0004] For example, a Chinese invention patent application with publication number CN116624137A discloses a method for processing deep rock mass while-drilling data and related equipment, the method comprising obtaining the torque, pressure, rotation speed and drilling speed of a drill rod during drilling into the deep rock mass; and performing median filtering on the torque, pressure, rotation speed and drilling speed respectively to obtain filtered torque, filtered pressure, filtered rotation speed and filtered drilling speed; and then determining a test rock strength index of the deep rock mass according to the filtered torque, the filtered pressure, the filtered rotation speed and the filtered drilling speed; and determining the uniaxial compressive strength of the deep rock mass according to the standard uniaxial compressive strength, the standard rock strength index and the test rock strength index, thereby realizing the determination of the uniaxial compressive strength of the deep rock mass by while-drilling measurement of the drill rod during drilling into the deep rock mass.

[0005] For example, a Chinese invention patent application with publication number CN117908118A discloses a method and related equipment for identifying rock discontinuities based on coda waves of seismic waves while drilling. The method includes obtaining seismic wave signals generated during the drilling of a drill rod into a rock mass to be identified, and determining a first coda wave signal and a second coda wave signal separated by a preset focal distance from the seismic wave signals; determining the propagation velocity of the coda wave of the seismic waves while drilling in the local rock mass corresponding to the preset focal distance based on the first coda wave information signal and the second coda wave signal; identifying the discontinuities of the rock mass to be identified based on the propagation velocity, and accurately determining the propagation velocity of the coda wave of the seismic waves while drilling in the local rock mass through coda wave analysis, so that the discontinuities of the rock mass can be accurately identified through the propagation velocity.

[0006] At present, the research on rock strength while drilling testing, including the above-mentioned patent application, mostly obtains drilling parameters by monitoring the drilling rig oil pressure. There is a lack of direct measurement of drilling parameters, and it is usually impossible to implement while drilling testing. Only rock strength parameters at discrete points can be measured. The test results obtained are only rock mechanical parameters. It is usually impossible to accurately survey the rock mechanical parameters, which makes the reliability of the test results of rock properties low. Summary of the invention

[0007] The technical problem to be solved by the present invention is to provide a deep rock mass strength in-hole and out-hole combined drilling testing equipment capable of accurately surveying the mechanical parameters of the rock mass.

[0008] In order to solve the above technical problems, the technical solution adopted by the present invention is: a deep rock strength in-hole and out-hole combined drilling test equipment, including a drilling rig, an out-hole drilling parameter test unit, a drill rod, an in-hole rock strength test unit, a hole surface seismic wave detector, a laser rangefinder, a control processing unit and an external drilling device;

[0009] The out-of-hole drilling parameter testing unit is connected between the drilling rig and the drill rod, the in-hole rock strength testing unit is connected between the drill rod and the external drilling device, the hole surface seismic wave detector is arranged on the drilling free surface, and the laser rangefinder is installed on the drilling rig; the drilling rig, the out-of-hole drilling parameter testing unit, the in-hole rock strength testing unit, the hole surface seismic wave detector and the laser rangefinder are all communicatively connected with the control processing unit.

[0010] As an improvement of the above solution: the in-hole rock strength testing unit includes an in-hole testing nipple, a hydraulic probe device, a distance counter and a pressure counter;

[0011] The in-hole test sub is a rod-shaped structure, and the in-hole test sub is connected between the drill pipe and the external drilling device;

[0012] The hydraulic probe device has a driving end and a probe end, the driving end of the hydraulic probe device is fixed inside the in-hole test short section, the probe end of the hydraulic probe device extends to the outside of the in-hole test short section, and the driving end of the hydraulic probe device is used to drive the probe end of the hydraulic probe device to move in a direction perpendicular to the central axis of the in-hole test short section;

[0013] The distance counter and the pressure counter are fixed on the in-hole test nipple and are both connected to the probe end of the hydraulic probe device;

[0014] The hydraulic probe device, the distance counter and the pressure counter are all in communication connection with the control processing unit.

[0015] As an improvement of the above scheme: the out-of-hole drilling parameter test unit includes an out-of-hole test sub, a pressure-torque composite sensor, an acceleration sensor, an inclination sensor and a rotation speed sensor;

[0016] The out-of-hole test sub is a rod-shaped structure, and the out-of-hole test sub is connected between the drilling rig and the drill rod;

[0017] The pressure torque composite sensor, acceleration sensor, inclination sensor and rotation speed sensor are all installed on the outer wall of the out-of-hole test short section, and the pressure torque composite sensor, acceleration sensor, inclination sensor and rotation speed sensor are all communicatively connected with the control processing unit.

[0018] The present invention also discloses a method for conducting a deep rock mass strength in-hole and out-hole combined testing while drilling using the deep rock mass strength in-hole and out-hole combined testing equipment, comprising the following steps:

[0019] S1. Install the deep rock mass strength inside and outside the hole while drilling joint testing equipment, and after installation, start the drilling rig to drill at the open surface;

[0020] S2, measuring the drilling depth of the borehole in real time by means of a laser rangefinder, and obtaining a time-drilling depth curve according to the drilling depth;

[0021] S3, obtaining rock strength information of discrete points in the hole by measuring with a rock strength testing unit in the hole;

[0022] S4, obtaining the out-of-hole drilling parameter information by real-time measurement through the out-of-hole drilling parameter testing unit, and combining the rock strength information and the out-of-hole drilling parameter information corresponding to the drilling depth of each single point in the discrete points in the hole into a training set in conjunction with the time-drilling depth curve obtained in step S2, and constructing a while-drilling intelligent inversion model of rock mechanical parameters through a BP neural network based on the training set, and training the while-drilling intelligent inversion model to obtain a training model, and continuously inverting the rock strength under the calibration of the rock strength information based on the training model to obtain a continuous rock compressive strength;

[0023] S5. Record the seismic wave signals generated during drilling and breaking the rock in real time through the seismic wave detector on the hole surface, and identify the rock structure surface based on the seismic wave signals;

[0024] S6. Calculate the rock mass compressive strength based on the rock compressive strength obtained in step S4 and the rock structural surface obtained in step S5.

[0025] As an improvement of the above solution: in step S3, the rock strength information of discrete points in the hole is measured by the in-hole rock strength testing unit according to the following steps:

[0026] S3-1. When the drilling depth increases by 1 to 2 m, the drilling of the drilling rig is stopped, and the driving end of the hydraulic probe device is used to drive the probe end of the hydraulic probe device to extend from the test short section in the hole. During the extension process of the probe end, the displacement value of the probe end is measured by the distance counter, and the pressure value of the probe end is measured by the pressure counter. A single-point test borehole wall pressure-deformation displacement curve is obtained based on the displacement value and the pressure value, and then the single-point elastic modulus and the compressive strength of the rock in the hole are obtained based on the single-point test borehole wall pressure-deformation displacement curve;

[0027] S3-2. After the measurement of the displacement value and the pressure value is completed, the driving end of the hydraulic probe device is used to drive the probe end of the hydraulic probe device to retract to the inside of the test short section in the hole, and the drilling rig is turned on to continue drilling. Step S3-1 is repeated to obtain the elastic modulus of multiple single points and the compressive strength of the rock in the hole at multiple single points. Finally, the elastic modulus of multiple single points and the compressive strength of the rock in the hole at multiple single points are combined to obtain the rock strength information of discrete points in the hole.

[0028] As an improvement of the above solution: in step S5, the rock mass structural surface is identified according to the seismic wave signal according to the following steps:

[0029] S5-1, the distance between the earthquake source and the moving distance is The two adjacent seismic wave signals are interferometrically analyzed in turn, one of the two seismic wave signals is taken as the reference channel, and the other of the two seismic wave signals is taken as the disturbance channel. According to the formula Calculate the correlation coefficient between the reference channel and the disturbance channel ;

[0030] ,

[0031] Mode middle, is the information without disturbance in the reference channel, is the information of disturbance in the disturbance channel, For drilling time, and is the time window corresponding to the signal without disturbance in the reference channel and the signal with disturbance in the disturbance channel;

[0032] S5-2, Basis formula The correlation coefficient obtained in Japanese style Calculate the variance ;

[0033] ,

[0034] Mode middle, is the main mean square frequency in the recorded waveform;

[0035] S5-3, Basis formula The variance obtained Japanese style Calculate the rock mass longitudinal wave velocity along the depth of the borehole ;

[0036] ;

[0037] S5-4, based on the obtained rock mass longitudinal wave velocity Identify rock mass structural surfaces.

[0038] As an improvement of the above scheme: In step S6, according to the formula Calculate the rock mass compressive strength ;

[0039] ,

[0040] Mode middle, is the compressive strength of rock, Parameters obtained based on the RMR engineering rock mass evaluation system and rock mass structural surface.

[0041] As an improvement of the above scheme: the evaluation indicators of the RMR engineering rock mass evaluation system include the uniaxial compressive strength of rock blocks, rock quality indicators, rock mass structural surface spacing, rock mass structural surface conditions, groundwater conditions and the relationship between the rock mass structural surface occurrence and the engineering direction.

[0042] As an improvement of the above scheme: in the step S1, when the deep rock strength inside and outside the hole combined drilling test equipment is installed, the hole surface seismic wave detector is fixed on the drilling free surface by hot melt adhesive, a pre-drilled borehole is set on the drilling free surface, and there is a 1m spacing between the hole surface seismic wave detector and the pre-drilled borehole on the drilling free surface in the radial direction of the borehole.

[0043] As an improvement of the above solution: in the above step S4, the out-of-hole drilling parameter information measured in real time by the out-of-hole drilling parameter testing unit includes torque parameters, pressure parameters, rotation speed parameters and inclination parameters.

[0044] The beneficial effects of the present invention are as follows: the present invention measures drilling parameters outside the hole through an out-of-hole drilling parameter test unit arranged between the drilling rig and the drill rod, measures rock strength inside the hole through an in-hole rock strength test unit, records seismic wave signals generated when a core tube or a drill bit breaks rock through a hole surface seismic wave detector, measures the drilling depth at the current time through a laser rangefinder, and then obtains parameters such as drilling speed, controls the drilling rig, the out-of-hole drilling parameter test unit, the in-hole rock strength test unit, the hole surface seismic wave detector and the laser rangefinder through a control processing unit, processes the detected data, and then realizes the identification of discrete rock strength, continuous rock strength, rock mass longitudinal wave velocity and rock mass structural surface respectively through in-hole, out-hole and hole surface while drilling tests, calculates rock mass strength parameters through rock mass structural surface and rock strength information, and can be used for while drilling measurement of rock mass strength parameters actually drilled by the drill bit, which helps to improve the accuracy of deep underground engineering surveys and provide reliable geological data for engineering disaster risk assessment and support design and construction. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 It is a structural schematic diagram of the in-hole and out-hole combined testing equipment for deep rock mass strength while drilling according to the present invention;

[0046] Figure 2 It is a structural schematic diagram of the in-hole rock strength testing unit of the present invention;

[0047] Figure 3 It is a structural schematic diagram of a medium-hole external drilling parameter testing unit of the present invention;

[0048] Figure 4 This is an internal structure diagram of the in-hole rock strength testing unit of the present invention;

[0049] Figure 5 This is an internal structure diagram of the hole external drilling parameter testing unit of the present invention;

[0050] Figure 6 It is the technical roadmap of the in-hole and out-hole combined testing method of deep rock mass strength while drilling of the present invention;

[0051] Figure 7 A schematic diagram of the pressure-deformation displacement curve of the borehole wall tested in the present invention;

[0052] Figure 8 It is a schematic diagram of the test results of the rock compressive strength in the hole at multiple single points along the drilling direction in the present invention;

[0053] Fig. 9It is a curve diagram showing the variation of the inclination parameter with the drilling depth in the hole external drilling parameter information of the present invention;

[0054] Fig.10 It is a curve diagram showing the change of pressure parameter with drilling depth in the hole external drilling parameter information of the present invention;

[0055] Fig.11 It is a curve diagram showing the change of the rotation speed parameter with the drilling depth in the hole external drilling parameter information of the present invention;

[0056] Fig.12 It is a curve diagram showing the change of torque parameter with drilling depth in the hole external drilling parameter information of the present invention;

[0057] Fig.13 It is the topological diagram of the BP neural network structure in the present invention;

[0058] Fig.14 It is a schematic diagram of the rock strength-drilling depth curve after calibration by multi-point strength test in the hole in the present invention;

[0059] Fig.15 It is a monitoring diagram of the seismic wave signal on the borehole surface corresponding to two adjacent depth points in the present invention;

[0060] Fig.16 It is the wave velocity along the borehole depth obtained by the borehole surface seismic wave interference calculation in the present invention, wherein the gray columnar part is the identified rock structure surface.

[0061] Marked in the figure are: 1-drilling rig, 2-out-hole drilling parameter test unit, 21-out-hole test short section, 22-second male head, 23-second female head, 3-drill rod, 4-in-hole rock strength test unit, 41-in-hole test short section, 42-hydraulic probe device, 43-first female head, 44-first male head, 5-hole surface seismic wave detector, 6-laser rangefinder, 7-control processing unit, 8-external drilling device, 9-drilling open surface. DETAILED DESCRIPTION

[0062] In order to facilitate the understanding of the present invention, the present invention is further described below in conjunction with the accompanying drawings.

[0063] In the description of the present invention, it should be noted that the directions or positional relationships indicated by terms such as “front”, “rear”, “left”, “right”, “up”, “down”, and “inside” are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of description. They do not indicate or imply that the device or component referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limitations on the present invention.

[0064] Meanwhile, throughout the specification, unless otherwise specified, the terms used herein should be understood as the meanings commonly used in the art; therefore, unless otherwise defined, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art to which the present invention belongs; if there is a conflict, the present specification takes precedence. Unless otherwise specified, various raw materials, reagents, instruments and equipment used in the present invention can be purchased from the market or prepared by existing methods.

[0065] like Figures 1 to 5 As shown, the deep rock strength in-hole and out-hole combined drilling test equipment disclosed in the present invention comprises a drilling rig 1, an out-hole drilling parameter test unit 2, a drill rod 3, an in-hole rock strength test unit 4, a hole surface seismic wave detector 5, a laser rangefinder 6, a control processing unit 7 and an external drilling device 8; one end of the out-hole drilling parameter test unit 2 is connected to the power head of the drilling rig 1, and the other end is connected to one end of the drill rod 3, so as to measure the drilling parameters outside the hole through the out-hole drilling parameter test unit 2 between the drilling rig 1 and the drill rod 3. One end of the in-hole rock strength test unit 4 is connected to the other end of the drill rod 3, and the other end is connected to an external drilling device 8 such as a core tube or a drill bit, so as to measure the rock strength in the hole through the in-hole rock strength test unit 4. The borehole surface seismic wave detector 5 is installed on the drilling free face 9, and the seismic wave signal generated by the core tube or drill bit when breaking the rock can be recorded by the borehole surface seismic wave detector 5. The drilling free face 9 is the working face where the drilling position is connected to the external outer diameter; the borehole surface seismic wave detector 5 adopts a high-frequency detector, and the frequency band of the rock breaking signal covered by the borehole surface seismic wave detector 5 is 10Hz~1500Hz. The laser rangefinder 6 is installed on the control console of the drilling rig 1, and the drilling depth at the current time can be measured by the laser rangefinder 6, and it is synchronized with the time of the on-site host to obtain parameters such as the drilling speed. The control processing unit 7 is connected to the drilling rig 1, the hole drilling parameter test unit 2, the rock strength test unit 4 in the hole, the borehole surface seismic wave detector 5 and the laser rangefinder 6, and the control processing unit 7 is the on-site host. The control processing unit 7 can control the drilling rig 1, the out-of-hole drilling parameter test unit 2, the in-hole rock strength test unit 4, the hole surface seismic wave detector 5 and the laser rangefinder 6, and process the data obtained by their detection, and then through the in-hole, out-of-hole and hole surface drilling tests, the discrete rock strength, continuous rock strength and the identification of the rock mass longitudinal wave velocity and the rock mass structural surface can be realized respectively, and the rock mass strength parameters can be calculated through the rock mass structural surface and rock strength information, which can be used for the in-hole drilling measurement of the rock mass strength parameters actually drilled by the drill bit, which helps to improve the accuracy of deep underground engineering surveys and provide reliable geological data for engineering disaster risk assessment and support design and construction.

[0066] Specifically, Figure 2As shown, the in-hole rock strength test unit 4 used in the present invention includes an in-hole test sub 41, a hydraulic probe device 42, a distance counter, a pressure counter, a first female head 43 and a first male head 44. The structure of the in-hole test sub 41 is set as a rod-shaped structure, one end of the in-hole test sub 41 is threadedly connected with the other end of the drill pipe 3 through the first female head 43, and the other end of the in-hole test sub 41 is threadedly connected with the external drilling device 8 through the first male head 44. The hydraulic probe device 42 has a driving end and a probe end. The driving end of the hydraulic probe device 42 is fixed inside the in-hole test sub 41, and the probe end of the hydraulic probe device 42 passes through the side wall of the in-hole test sub 41 and extends to the outside of the in-hole test sub 41. The driving end of the hydraulic probe device 42 is used to drive the probe end of the hydraulic probe device 42 to move in a direction perpendicular to the central axis of the in-hole test sub 41. The distance counter is fixed on the in-hole test sub 41 and connected to the probe end of the hydraulic probe device 42. The pressure counter is fixed on the in-hole test nipple 41 and connected to the probe end of the hydraulic probe device 42 ; the hydraulic probe device 42 , the distance counter and the pressure counter are all in communication connection with the control processing unit 7 .

[0067] One end of the in-hole test sub 41 of a rod-shaped structure is connected to the other end of the drill rod 3 through a first female head 43, and the other end is connected to the external drilling device 8 through a first male head 44, so that the in-hole test sub 41 is installed between the drill rod 3 and the external drilling device 8 as a small drill rod. The driving end of the hydraulic probe device 42 is fixed inside the in-hole test sub 41, and the probe end of the hydraulic probe device 42 passes through the side wall of the in-hole test sub 41 and extends to the outside of the in-hole test sub 41, so that the driving end of the hydraulic probe device 42 drives the probe end of the hydraulic probe device 42 to move in a direction perpendicular to the central axis of the in-hole test sub 41, so that the probe end of the hydraulic probe device 42 can be pressed into the rock of the borehole wall. Specifically, the driving end of the hydraulic probe device 42 can adopt a hydraulic power mechanism having components such as a motor, a hydraulic chamber, and a hydraulic plunger; the probe end of the hydraulic probe device 42 is a probe, and the probe is driven downward by the hydraulic power mechanism. The distance counter fixed on the in-hole test sub 41 is connected to the probe end of the hydraulic probe device 42, and the distance counter can be used to measure the displacement change of the probe end of the hydraulic probe device 42 during the pressing process. The pressure counter fixed on the in-hole test sub 41 is connected to the probe end of the hydraulic probe device 42, and the pressure counter can be used to measure the pressure value change of the probe end of the hydraulic probe device 42 during the pressing process. The hydraulic probe device 42, the distance counter, and the pressure counter are all connected to the control processing unit 7 for communication, and the control processing unit 7 can be used to control the hydraulic probe device 42, and process and analyze the displacement, pressure value, and other data detected by the distance counter and the pressure counter.

[0068] like Figure 4 As shown, in some possible embodiments, the in-hole rock strength testing unit 4 also includes a single-chip microcomputer, an A / D conversion circuit, and a signal amplification circuit. The single-chip microcomputer is provided with a data storage module, a motor hydraulic drive module and a self-power supply module. The distance counter is connected to the signal amplification circuit through the corresponding signal acquisition circuit, the pressure counter is connected to the signal amplification circuit through the corresponding signal acquisition circuit, the signal amplification circuit is connected to the single-chip microcomputer through the A / D conversion circuit, the single-chip microcomputer is connected to the hydraulic probe device 42 and is wirelessly connected to the control processing unit 7, so that the hydraulic probe device 42, the distance counter and the pressure counter are communicated with the control processing unit 7 through the single-chip microcomputer, so that the data detected by the distance counter and the pressure counter are recorded in the data storage module in the single-chip microcomputer through the A / D conversion circuit and the data is transmitted to the control processing unit 7, and the hydraulic probe device 42 is controlled by the motor hydraulic drive module; and the power supply is performed by the self-power supply module.

[0069] Specifically, Figure 3 As shown, the out-of-hole drilling parameter test unit 2 used in the present invention includes an out-of-hole test sub 21, a pressure-torque composite sensor, an acceleration sensor, an inclination sensor, a rotation speed sensor, a second male head 22 and a second female head 23. The out-of-hole test sub 21 is set as a rod-shaped structure, one end of the out-of-hole test sub 21 is threadedly connected to the power head of the drilling rig 1 through the second male head 22, and the other end of the out-of-hole test sub 21 is threadedly connected to one end of the drill rod 3 through the second female head 23. The pressure-torque composite sensor is installed on the outer wall of the out-of-hole test sub 21. The acceleration sensor is installed on the outer wall of the out-of-hole test sub 21. The inclination sensor is installed on the outer wall of the out-of-hole test sub 21. The rotation speed sensor is installed on the out-of-hole test sub 21. The pressure-torque composite sensor, the acceleration sensor, the inclination sensor and the rotation speed sensor are all connected to the control processing unit 7 for communication.

[0070] One end of the rod-shaped out-of-hole test sub 21 is connected to the drilling rig 1 through the second male connector 22, and the other end is connected to one end of the drill rod 3 through the second female connector 23, so that the out-of-hole test sub 21 is installed between the drill rod 3 and the drilling rig 1 as a small drill rod. The pressure-torque composite sensor, the acceleration sensor, and the inclination sensor are installed on the outer wall of the out-of-hole test sub 21, and the speed sensor is installed on the out-of-hole test sub 21, so as to measure drilling parameters such as torque, pressure, speed, and inclination through the pressure-torque composite sensor, the acceleration sensor, the inclination sensor, and the speed sensor; the pressure-torque composite sensor, the acceleration sensor, the inclination sensor, and the speed sensor are all connected to the control processing unit 7 in communication, so as to obtain and process the data detected by the pressure-torque composite sensor, the acceleration sensor, the inclination sensor, and the speed sensor through the control processing unit 7.

[0071] like Figure 5As shown, in some possible embodiments, the out-of-hole drilling parameter test unit 2 also includes a single-chip microcomputer, an A / D conversion circuit, and a signal amplification circuit. The single-chip microcomputer is provided with a data storage module, a wireless transmission module and a self-power supply module. The pressure torque composite sensor, the acceleration sensor, the inclination sensor and the speed sensor are respectively connected to the signal amplification circuit through corresponding signal acquisition circuits, the signal amplification circuit is connected to the single-chip microcomputer through the A / D conversion circuit, and the single-chip microcomputer is wirelessly connected to the control processing unit 7, so that the pressure torque composite sensor, the acceleration sensor, the inclination sensor and the speed sensor are communicated with the control processing unit 7 through the single-chip microcomputer, so that the data detected by the pressure torque composite sensor, the acceleration sensor, the inclination sensor and the speed sensor are recorded in the data storage module in the single-chip microcomputer through the A / D conversion circuit, and are wirelessly connected to the control processing unit 7 located in the drilling rig console through the wireless transmission module, and the data are displayed on the control processing unit 7 in real time; power supply is performed through the self-power supply module.

[0072] like Figure 6 As shown, the deep rock mass strength inside and outside the hole while drilling joint testing method disclosed in the present invention adopts the deep rock mass strength inside and outside the hole while drilling joint testing equipment described above, and performs the following steps:

[0073] S1. Install the deep rock mass strength in-hole and out-hole combined drilling test equipment, fix the hole surface seismic wave detector 5 on the drilling free surface 9 by hot melt adhesive, set a pre-drilled hole on the drilling free surface 9, and there is a 1m spacing between the hole surface seismic wave detector 5 and the pre-drilled hole on the drilling free surface 9 in the radial direction of the drilling hole. After installation, start the drilling rig 1 to drill at the drilling free surface 9;

[0074] S2, measuring the drilling depth of the borehole in real time by means of a laser rangefinder 6, which calculates the drilling depth by measuring the forward and backward movement of the power head of the drilling rig 1, and obtains a time-drilling depth curve in conjunction with the time recorded by the on-site host;

[0075] S3, obtaining rock strength information of discrete points in the hole by measuring through the in-hole rock strength testing unit 4;

[0076] S4, obtaining the out-of-hole drilling parameter information by real-time measurement through the out-of-hole drilling parameter testing unit 2, and combining the rock strength information and the out-of-hole drilling parameter information corresponding to the drilling depth of each single point in the discrete points in the hole into a training set in conjunction with the time-drilling depth curve obtained in step S2, and constructing a drilling-while-drilling intelligent inversion model of rock mechanical parameters through a BP neural network based on the training set, and training the drilling-while-drilling intelligent inversion model to obtain a training model, and continuously inverting the rock strength under the calibration of the rock strength information based on the training model to obtain a continuous rock compressive strength;

[0077] S5, using the hole surface seismic wave detector 5 to record in real time the seismic wave signal generated when drilling and breaking the rock, and identifying the rock mass structural surface based on the seismic wave signal;

[0078] S6. Calculate the rock mass compressive strength based on the rock compressive strength obtained in step S4 and the rock structural surface obtained in step S5.

[0079] Specifically, the in-hole and out-hole combined testing method for deep rock mass strength disclosed in the present invention has the overall concept of measuring the current drilling depth of the borehole, that is, the current testing depth, in real time by means of a laser rangefinder 6; testing the borehole wall pressure-deformation displacement curve by means of an in-hole rock strength testing unit 4, thereby calculating the rock strength information of several single points in the discrete points in the borehole along the drilling direction, including information such as the static elastic modulus of the rock and the ultimate compressive strength of the rock; such as Figures 9 to 12 As shown, the out-of-hole drilling parameter information, including torque, pressure, rotation speed, inclination and other information, is measured in real time by the out-of-hole drilling parameter testing unit 2. In combination with the time-drilling depth curve, the rock strength information obtained by testing the known discrete points in the hole is used as the known information, and the out-of-hole drilling parameter information such as torque, pressure, rotation speed, inclination and other information obtained outside the hole at the corresponding point is used as the training set. According to the training set, a drilling-while-intelligent inversion model of rock mechanical parameters is constructed through a BP neural network, and the drilling-while-intelligent inversion model is trained. The training includes evaluating the prediction effect of the drilling-while-intelligent inversion model and performing Screening is performed to optimize and calibrate the rock strength. The obtained training model can obtain the rock compressive strength information from the torque, pressure, rotation speed and inclination information as input. Since the collection of drilling parameter information outside the hole is continuous along the borehole, the continuous rock compressive strength can be obtained; the seismic wave signal generated during drilling and rock breaking is recorded in real time by the hole surface seismic wave detector 5, and the rock structure surface is identified based on the seismic wave signal; the rock compressive strength is calculated based on the rock compressive strength and the rock structure surface, thereby realizing the use of the drilling measurement information outside the hole, on the hole surface and inside the hole to quickly, accurately and continuously invert the rock strength parameters.

[0080] The BP neural network used in the present invention is an artificial intelligence algorithm created by imitating the excitation process of the nervous system in the biological brain. This method allows the neural network to learn the mapping law between input and output, and then directly construct the nonlinear relationship between input and output through error back propagation, forming a feedforward neural network, namely Backpropagation Neural Network. Fig.13As shown in the figure, the BP neural network consists of a three-layer structure of input layer, output layer and hidden layer. Each layer contains several nodes. The connections between nodes between layers constitute neurons. Each node can receive input signals from other nodes and generate outputs by performing regular operations on the input signals. The training principle of the BP neural network is the error back propagation algorithm. The algorithm inputs the training samples into the neural network, obtains the initial prediction results through the hidden layer and the output layer, then calculates the error of the output layer, and back propagates the error. The weight and bias of each node in the neural network are adjusted according to the error size to make the next network prediction result more accurate. The training process of the BP neural network mainly includes the following steps: forward propagation stage, error calculation stage, back propagation stage and repeated calculation stage. Compared with other machine learning methods, the back propagation nature of the BP neural network will make it more advantageous in dealing with nonlinear problems, improving computational efficiency and generalization ability in theory. It is a feasible method to construct complex nonlinear mapping relationships between drilling parameters and rock mechanics parameters. As shown in the figure, the training process of the BP neural network mainly includes the following steps: forward propagation stage, error calculation stage, back propagation stage and repeated calculation stage. Compared with other machine learning methods, the back propagation nature of the BP neural network will make it more advantageous in dealing with nonlinear problems, improving computational efficiency and generalization ability in theory. It is a feasible method to construct complex nonlinear mapping relationships between drilling parameters and rock mechanics parameters. Fig.14 The trained model can continuously invert rock strength under the calibration of rock strength tested in known holes.

[0081] In the in-hole and out-hole combined testing method for deep rock mass strength disclosed in the present invention, when the in-hole rock strength testing unit 4 measures the rock strength information of discrete points in the hole, the following steps are followed:

[0082] S3-1. When the drilling depth of the drilling rig 1 increases by 1 to 2 m, the drilling operation of the drilling rig 1 is stopped, and the driving end of the hydraulic probe device 42 is used to drive the probe end of the hydraulic probe device 42 to extend from the side wall of the test short section 41 in the hole. During the extension process, the displacement value of the probe end is measured by the distance counter, and the pressure value of the probe end is measured by the pressure counter. According to the displacement value and the pressure value, the following is obtained: Figure 7 The single-point test borehole wall pressure-deformation displacement curve shown is used to obtain the single-point elastic modulus and the rock compressive strength in the hole according to the test borehole wall pressure-deformation displacement curve;

[0083] S3-2. After the displacement value and the pressure value are measured, the driving end of the hydraulic probe device 42 is used to drive the probe end of the hydraulic probe device 42 to extend from the side wall of the in-hole test pup joint 41 into the interior of the in-hole test pup joint 41, and the drilling rig 1 is turned on to continue drilling, and step S3-1 is repeated to obtain the elastic modulus of multiple single points and the in-hole rock compressive strength of several single points, and the elastic modulus of multiple single points and the in-hole rock compressive strength of multiple single points are combined to obtain the rock strength information of discrete points in the hole.

[0084] Specifically, the elastic modulus of a single point and the compressive strength of the rock in the hole can be obtained according to the test borehole wall pressure-deformation displacement curve according to the following principles, or can be determined according to the curve shape. The pressure section less than 5MPa in the test borehole wall pressure-deformation displacement curve does not need to be considered in the data processing. The secant modulus of the 5-50MPa stress section is defined as the deformation modulus E, that is, the elastic modulus. The stress section above 50MPa is regarded as the compressive strength of the rock in the hole. This is because the rock in the stress section above 50MPa is destroyed, the displacement continues to increase, but the rock stress does not increase. Through the rock strength test at different depths, the following can be obtained: Figure 8 Discrete rock strength points shown.

[0085] In the method for combined in-hole and out-hole testing of deep rock mass strength disclosed in the present invention, when identifying the rock mass structural surface based on the seismic wave signal, the following steps are followed:

[0086] S5-1, the distance between the earthquake source and the moving distance is The two adjacent seismic wave signals are interferometrically analyzed in turn, one of the two seismic wave signals is taken as the reference channel, and the other of the two seismic wave signals is taken as the disturbance channel. According to the formula Calculate the correlation coefficient between the reference channel and the disturbance channel ;

[0087] ,

[0088] Mode middle, is the information without disturbance in the reference channel, is the information of disturbance in the disturbance channel, For drilling time, and is the time window corresponding to the signal without disturbance in the reference channel and the signal with disturbance in the disturbance channel;

[0089] S5-2, Basis formula The correlation coefficient obtained in Japanese style Calculate the variance ;

[0090] ,

[0091] Mode middle, is the main mean square frequency in the recorded waveform;

[0092] S5-3, Basis formula The variance obtained Japanese style Calculate the rock mass longitudinal wave velocity along the depth of the borehole ;

[0093] ;

[0094] S5-4, based on the obtained rock mass longitudinal wave velocity Identify rock mass structural surfaces.

[0095] In the above steps, the rock breaking vibration recorded by the borehole surface seismic wave detector 5 is used to calculate the rock mass longitudinal wave velocity along the borehole depth direction by interferometric analysis of the signals between the unit drilling depths, and then the dynamic elastic modulus of the rock is obtained, and the rock mass structural surface is determined by identifying the low-velocity area. For example, Fig.15 One of the two seismic wave signals in the image is used as the reference channel, that is, the signal without disturbance. , and the other channel is used as the disturbance channel, that is, the disturbance signal , we can get the comparison between the disturbed signal and the unperturbed signal, and we can find that the two seismic wave signals are very similar as a whole, and there is a phase difference between the two seismic wave signals, which can be obtained according to the formula Calculate the correlation coefficient between the reference channel and the disturbance channel ; The distance between the source and the receiver and the variance of the inconsistent phase disturbance are related. Since the position of the receiver in the while-drilling seismic wave monitoring remains unchanged, the spacing between the movement of the adjacent sources is It is also related to the variance, and thus to the correlation coefficient , that is, the cross-correlation value The maximum cross-correlation value and variance of the travel time disturbance are derived. The relationship between , according to the formula Get the variance .

[0096] When the source displacement distance is When , the source displacement distance can be estimated based on the variance of the travel time disturbance , see formula :

[0097] ,

[0098] Mode middle, is the estimated value of the P wave of the medium. Since the drilling signal is a continuous impact drill vibration, in this embodiment, the seismic wave signal is taken every 0.1m for interference analysis, that is, = 0.1m, so we can use the formula Calculate the longitudinal wave velocity By analyzing the interference between two adjacent seismic wave signals at a point of 0.1 m, the longitudinal wave velocity of the rock mass that varies with depth can be obtained, such as Fig.16 As shown, the longitudinal wave velocity of the rock mass can be identified. It can be considered that when the velocity is less than 50% of the background, there is an obvious rock structure surface, that is, a low-velocity zone.

[0099] In step S6 of the method for combined testing of deep rock mass strength inside and outside the hole while drilling disclosed by the present invention, the rock mass compressive strength is obtained by calculation according to the rock compressive strength and the rock mass structural surface. Calculate the rock mass compressive strength ;

[0100] ;

[0101] The principle of the above calculation formula is as follows: According to the Hoek-Brown criterion, the rock compressive strength can be converted into the rock mass compressive strength. is the rock strength obtained by drilling, such as Fig.14 shown. According to the parameters obtained from the RMR engineering rock mass evaluation system and rock mass structural surface, according to the formula Calculated :

[0102] ,

[0103] Mode In the present embodiment, the RMR engineering rock mass evaluation system is a method for determining the quality grade of rock mass. The evaluation indexes of the RMR engineering rock mass evaluation system include the uniaxial compressive strength of rock blocks ( )、Rock Quality Index RQD( )、Spacing between rock mass structural planes( )、rock mass structural surface conditions( )、groundwater conditions( ) and the relationship between the rock mass structural surface and the project direction ( ), a total of six indicators are used as basic parameters to score the main factors affecting the stability of the rock mass, and their sum is used as the RMR value of the rock mass, that is, according to the formula Calculate the RMR value:

[0104] ,

[0105] Mode The uniaxial compressive strength of rock blocks ( )、Rock Quality Index RQD( )、Spacing between rock mass structural planes( ) is the quantitative standard, and the rock mass structural surface condition ( )、groundwater conditions( ) and the relationship between the rock mass structural surface and the project direction ( ) is a qualitative parameter. The specific scoring table can be found in Tables 1 to 6, where The rock strength is selected based on the rock strength tested inside and outside the hole. Fig.14 Select; Joint information , and The rock mass structural surface can be identified and counted through the low-velocity zone obtained by hole surface seismic wave interference calculation.

[0106] Table 1 Uniaxial compressive strength of intact rock Rating Sheet

[0107]

[0108] Table 2 Rock quality indicators Rating Sheet

[0109]

[0110] Table 3 Joint spacing Rating Sheet

[0111]

[0112] Table 4 Joint characteristics Rating Sheet

[0113]

[0114] Table 5 Groundwater conditions Rating Sheet

[0115]

[0116] Table 6 Joint direction Rating Sheet

[0117]

[0118] The beneficial effects of the present invention are mainly manifested in: (1) Compared with the traditional test-while-drilling method, the rock strength measured by the in-hole test-while-drilling can be used to calibrate the rock strength measured by the inversion of the drilling parameters outside the hole, thereby obtaining a reliable and continuous rock strength curve that varies with depth; (2) Compared with the traditional test-while-drilling method, the present invention realizes a probe-type rock strength test by using a short section for the in-hole rock strength test-while-drilling, thereby obtaining the in-situ elastic modulus and single-point rock strength information; (3) Compared with the traditional test-while-drilling method, the present invention can obtain the longitudinal wave velocity of the rock mass along the depth direction of the borehole while drilling by using the seismic wave interferometry method, thereby identifying the rock mass structural surface through the low-speed area; (4) Compared with the traditional method for identifying rock strength while drilling, the present invention can calculate the rock mass strength information by analyzing the structural surface and rock strength.

[0119] Finally, it should be noted that the terms "comprises," "includes," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements that are inherent to such process, method, article, or apparatus.

[0120] Although preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they become aware of the basic creative concepts; therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0121] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention; thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these changes and variations.

Claims

1. A combined in-hole and out-hole testing method for deep rock mass strength while drilling, characterized by: A deep rock mass strength in-hole and out-hole combined testing equipment is used, and the deep rock mass strength in-hole and out-hole combined testing equipment comprises a drilling rig (1), an out-hole drilling parameter testing unit (2), a drill rod (3), an in-hole rock strength testing unit (4), a hole surface seismic wave detector (5), a laser rangefinder (6), a control processing unit (7) and an external drilling device (8); The out-of-hole drilling parameter test unit (2) is connected between the drilling rig (1) and the drill rod (3), the in-hole rock strength test unit (4) is connected between the drill rod (3) and the external drilling device (8), the surface-of-hole seismic wave detector (5) is arranged on the drilling open face (9), and the laser rangefinder (6) is installed on the drilling rig (1); the drilling rig (1), the out-of-hole drilling parameter test unit (2), the in-hole rock strength test unit (4), the surface-of-hole seismic wave detector (5) and the laser rangefinder (6) are all connected to the control processing unit (7) for communication; The in-hole rock strength testing unit (4) comprises an in-hole testing nipple (41), a hydraulic probe device (42), a distance counter and a pressure counter; The in-hole test short section (41) is a rod-shaped structure, and the in-hole test short section (41) is connected between the drill rod (3) and the external drilling device (8); The hydraulic probe device (42) has a driving end and a probe end, the driving end of the hydraulic probe device (42) is fixed inside the in-hole test short section (41), the probe end of the hydraulic probe device (42) extends to the outside of the in-hole test short section (41), and the driving end of the hydraulic probe device (42) is used to drive the probe end of the hydraulic probe device (42) to move in a direction perpendicular to the central axis of the in-hole test short section (41); The distance counter and the pressure counter are fixed on the in-hole test nipple (41) and are both connected to the probe end of the hydraulic probe device (42); The hydraulic probe device (42), the distance counter and the pressure counter are all in communication connection with the control processing unit (7); The out-of-hole drilling parameter testing unit (2) comprises an out-of-hole testing sub (21), a pressure-torque composite sensor, an acceleration sensor, an inclination sensor and a rotation speed sensor; The out-of-hole test short section (21) is a rod-shaped structure, and the out-of-hole test short section (21) is connected between the drilling rig (1) and the drill rod (3); The pressure torque composite sensor, acceleration sensor, inclination sensor and rotation speed sensor are all mounted on the outer wall of the out-of-hole test sub (21), and the pressure torque composite sensor, acceleration sensor, inclination sensor and rotation speed sensor are all communicatively connected to the control processing unit (7); The deep rock mass strength in-hole and out-hole combined drilling test method includes the following steps: S1. Installing the deep rock mass strength in-hole and out-hole combined drilling test equipment, after installation, starting the drilling rig (1) to drill at the drilling free surface (9); S2, measuring the drilling depth of the borehole in real time by means of a laser rangefinder (6), and obtaining a time-drilling depth curve according to the drilling depth; S3, obtaining rock strength information of discrete points in the hole by measuring with the in-hole rock strength testing unit (4); S4, obtaining the out-of-hole drilling parameter information by real-time measurement through the out-of-hole drilling parameter testing unit (2), combining the rock strength information and the out-of-hole drilling parameter information corresponding to the drilling depth of each single point in the discrete points in the hole into a training set by means of the time-drilling depth curve obtained in step S2, constructing a while-drilling intelligent inversion model of rock mechanical parameters through a BP neural network based on the training set, training the while-drilling intelligent inversion model to obtain a training model, and continuously inverting the rock strength under the calibration of the rock strength information based on the training model to obtain a continuous rock compressive strength; S5, using a seismic wave detector (5) on the hole surface to record in real time the seismic wave signal generated when drilling and breaking the rock, and identifying the rock mass structural surface based on the seismic wave signal; S6. Calculate the rock mass compressive strength based on the rock compressive strength obtained in step S4 and the rock structural surface obtained in step S5; According to formula (4), the rock mass compressive strength σ is calculated as c ; , In formula (4), σ ci is the rock compressive strength, and S is the parameter obtained according to the RMR engineering rock mass evaluation system and the rock mass structural surface.

2. The deep rock mass strength in-hole and out-hole combined drilling test method according to claim 1, characterized in that: In step S3, the rock strength information of discrete points in the hole is measured by the in-hole rock strength testing unit (4) according to the following steps: S3-1, when the drilling depth increases by 1 to 2 m, the drilling of the drilling rig (1) is stopped, and the driving end of the hydraulic probe device (42) is used to drive the probe end of the hydraulic probe device (42) to extend from the test short section (41) in the hole, and during the extension of the probe end, the displacement value of the probe end is measured by a distance counter, and the pressure value of the probe end is measured by a pressure counter, and a single-point test borehole wall pressure-deformation displacement curve is obtained based on the displacement value and the pressure value, and then the single-point elastic modulus and the compressive strength of the rock in the hole are obtained based on the single-point test borehole wall pressure-deformation displacement curve; S3-2. After the displacement and pressure values ​​are measured, the driving end of the hydraulic probe device (42) is used to drive the probe end of the hydraulic probe device (42) to retract into the interior of the in-hole test pup joint (41), and the drilling rig (1) is turned on to continue drilling. Step S3-1 is repeated to obtain elastic moduli of multiple single points and compressive strengths of the in-hole rock at multiple single points. Finally, the elastic moduli of multiple single points and the compressive strengths of the in-hole rock at multiple single points are combined to obtain rock strength information of discrete points in the hole.

3. The deep rock mass strength in-hole and out-hole combined drilling test method according to claim 2, characterized in that: In step S5, the following steps are followed when identifying the rock mass structural surface based on the seismic wave signal: S5-1, interferometric analysis is performed on two adjacent seismic wave signals whose source movement interval is d, one of the two seismic wave signals is taken as a reference channel, and the other of the two seismic wave signals is taken as a disturbance channel, and the correlation coefficient R between the reference channel and the disturbance channel is calculated according to formula (1); , In formula (1), A(t) is the information without disturbance in the reference channel, B(t[1+∈]) is the information with disturbance in the disturbance channel, t is the drilling time, t1 and t2 are the time windows corresponding to the signal without disturbance in the reference channel and the signal with disturbance in the disturbance channel; S5-2. Calculate the variance based on the correlation coefficient R obtained in formula (1) and formula (2) , In formula (2), is the main mean square frequency in the recorded waveform; S5-3, according to the variance obtained in formula (2) The longitudinal wave velocity v of the rock mass along the depth direction of the borehole is calculated by formula (3); S5-4. Identify the rock mass structural surface based on the obtained rock mass longitudinal wave velocity v.

4. The deep rock mass strength in-hole and out-hole combined drilling test method according to claim 1, characterized in that: The evaluation indicators of the RMR engineering rock mass evaluation system include uniaxial compressive strength of rock blocks, rock quality indicators, rock mass structural plane spacing, rock mass structural plane conditions, groundwater conditions, and the relationship between the rock mass structural plane occurrence and the engineering direction.

5. The deep rock mass strength in-hole and out-hole combined drilling test method according to claim 1, characterized in that: In the step S1, when installing the deep rock mass strength in-hole combined drilling test equipment, the hole surface seismic wave detector (5) is fixed to the drilling free surface (9) by hot melt adhesive, and a pre-drilled hole is set on the drilling free surface (9), and there is a spacing of 1m between the hole surface seismic wave detector (5) and the pre-drilled hole on the drilling free surface (9) in the radial direction of the drilling hole.

6. The deep rock mass strength in-hole and out-hole combined drilling test method according to claim 1, characterized in that: In the step S4, the out-of-hole drilling parameter information obtained by real-time measurement by the out-of-hole drilling parameter testing unit (2) includes torque parameters, pressure parameters, rotation speed parameters and inclination parameters.

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