Device and method for in-situ drawing test of underwater rock mass

Abstract

The invention provides a device and a method for an in-situ drawing test of an underwater rock mass, and belongs to the field of marine geological survey. The device comprises a core drilling machine, a core drilling rod, a tightening device, a hydraulic jack, a vibrating wire dynamometer and a data acquisition instrument, the core drilling machine is used for controlling the core drilling rod to move or rotatably drill a target rock mass, the core drilling rod is vertically arranged, the top of the core drilling rod is connected with the core drilling machine, and the tightening device is arranged at the end, close to the bottom, of the core drilling rod. The tightening device is used for locking a drilled target rock mass, the hydraulic jack and the vibrating wire type dynamometer are arranged on the rock core drill rod in a sleeving manner, the hydraulic jack is used for providing drawing force for the rock core drill rod, the vibrating wire type dynamometer is used for measuring the drawing force of the hydraulic jack, and the data acquisition instrument is in signal connection with the vibrating wire type dynamometer. By adopting the device and the method for the in-situ drawing test of the underwater rock mass, provided by the embodiment of the invention, the problem of relatively low accuracy of drawing test data in the prior art can be solved.

Description

Technical Field

[0001] The invention relates to the field of marine geological survey, and in particular to a device and method for in-situ pull-out testing of underwater rock masses. Background Art

[0002] Marine geological survey refers to the exploration and detection of the geological conditions of the seabed in a certain area through various means and methods. Through marine geological survey, information such as seabed geological structure, stratum distribution, sediment type, mineral resources and geological disasters can be obtained. In marine geological survey, core drilling technology is one of the main methods to obtain deep seabed geological samples. Long columnar core samples are extracted from the seabed through drilling equipment. These samples retain the continuity of geological sequences and provide geological history and environmental information.

[0003] The basic physical and mechanical parameter of rock mass tensile strength is one of the most important properties of rock mechanics, which refers to the average tensile stress on the fracture surface of the rock mass when the rock sample is destroyed under the action of tensile stress. The tensile strength plays a guiding role in the further engineering design of rock drilling, blasting, pile foundation bearing, etc. In the prior art, the tensile test of underwater rock mass is usually carried out by taking the rock mass out of the water and then transporting it to the laboratory for tensile test.

[0004] The existing pull-out test methods for underwater rock masses make it difficult to obtain key data such as the tensile strength and adhesion of the rock in the in-situ environment. In addition, some rock masses, such as reef limestone, will accelerate oxidation after being taken out of water, resulting in laboratory test results often being affected by time delays and environmental changes, and the accuracy of the obtained pull-out test data is low. Summary of the invention

[0005] The embodiment of the present invention provides a device and method for in-situ pull-out testing of underwater rock mass, which can solve the problem of low accuracy of pull-out test data in the prior art. The technical solution is as follows:

[0006] In a first aspect, a device for in-situ pull-out testing of underwater rock mass comprises: a core drill, a core drill rod, a clamping device, a hydraulic jack, a vibrating wire dynamometer and a data acquisition instrument,

[0007] The core drill rig is used to control the core drill rod to move or rotate to drill a target rock mass. The core drill rod is a cylindrical structure with openings at both ends. The core drill rod is vertically arranged. The top of the core drill rod is connected to the core drill rig. The clamping device is arranged at one end of the core drill rod close to the bottom. The clamping device is used to lock the drilled target rock mass. The hydraulic jack and the vibrating string dynamometer are sleeved on the core drill rod. The hydraulic jack is used to provide a pulling force to the core drill rod. The vibrating string dynamometer is used to test the pulling force of the hydraulic jack. The data acquisition instrument is connected to the signal of the vibrating string dynamometer to calculate the tensile strength of the target rock mass based on the pulling force.

[0008] Optionally, the core drill rod includes an inner wall and an outer wall, an annular space is arranged between the inner wall and the outer wall, the distance between the inner wall and the outer wall near the bottom of the core drill rod gradually decreases, the tightening device is a cylindrical structure, slidably arranged in the annular space, the tightening device includes a tightening pipe and a steel strand, the tightening pipe includes a fixed end, a clamping end and a bearing, the fixed end is arranged above the clamping end, the fixed end and the clamping end are connected through the bearing, the fixed end matches the inner wall and the outer wall at the bottom end of the core drill rod, the steel strand is spirally wound on the tightening pipe, one end of the steel strand is fixed to the fixed end, and the other end is fixed to the clamping end.

[0009] Optionally, a clamping ring is sleeved on the top of the fixed end, and the clamping ring matches the inner wall and the outer wall of the bottom end of the core drill rod.

[0010] Optionally, the clamping ring is made of wear-resistant steel.

[0011] Optionally, the clamping end is provided with a contraction groove along the length direction.

[0012] Optionally, a plurality of contraction grooves are provided, and the plurality of contraction grooves are evenly distributed along the circumference of the clamping pipe.

[0013] Optionally, the clamping pipe is provided with a wiring groove matching the steel strand.

[0014] Optionally, an anti-slip pad is provided on the inner side wall of the clamping end.

[0015] Optionally, it also includes a working platform and a reaction plate, the working platform is provided with a borehole, the core drill rod is inserted into the borehole, the vibrating string dynamometer is arranged on the working platform, the hydraulic jack is arranged on the vibrating string dynamometer, and the reaction plate is arranged between the hydraulic jack and the vibrating string dynamometer.

[0016] In a second aspect, a method for in-situ pull-out testing of underwater rock mass comprises the aforementioned device for in-situ pull-out testing of underwater rock mass, comprising the following steps:

[0017] Step 1: using the core drilling rig to control the core drill rod to drill the target rock mass underwater;

[0018] Step 2: fixing the drilled target rock mass and the core drill rod by means of the clamping device;

[0019] Step 3: Providing a pulling force to the core drill rod by means of the hydraulic jack until the target rock mass is broken, during which the pulling force data provided by the hydraulic jack is measured by means of the vibrating wire dynamometer;

[0020] Step 4: The data acquisition instrument is used to collect and record the pull-out force data measured by the vibrating-wire dynamometer, and the tensile strength of the target rock mass is calculated.

[0021] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0022] The embodiment of the present invention provides a device and method for in-situ pull-out test of underwater rock mass. The core drill rod is controlled by a core drill rig to drill the target rock mass underwater, and then the drilled target rock mass and the core drill rod are fixed by a clamp device. Then, a pull-out force is provided to the core drill rod by a hydraulic jack until the target rock mass is broken. During the pull-out, the pull-out force data provided by the hydraulic jack is measured by a vibrating-wire dynamometer. Finally, the pull-out force data measured by the vibrating-wire dynamometer is collected and recorded by a data acquisition instrument, and the tensile strength of the target rock mass is calculated. The device provided by the embodiment of the present invention does not need to be transported to a laboratory after the target rock mass is taken out for pull-out test. After the target rock mass is drilled underwater, the pull-out test is directly performed in the in-situ environment. This device and method can eliminate the influence of the time delay caused by the transportation of the rock mass on the test results, and can effectively solve the problem of low accuracy of pull-out test data in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0024] Figure 1 is a schematic diagram of the overall structure of the device provided by an embodiment of the present invention;

[0025] Figure 2It is a schematic diagram of the assembly structure of a core drill rod and a clamping device provided in an embodiment of the present invention;

[0026] Figure 3 It is a schematic cross-sectional view of the assembly of a core drill rod and a clamp pipe provided by an embodiment of the present invention;

[0027] Figure 4 The embodiment of the present invention provides Figure 3 A schematic diagram of the enlarged structure at point A;

[0028] Figure 5 is a schematic cross-sectional view of a clamp pipe fitting provided by an embodiment of the present invention;

[0029] Figure 6 It is a schematic diagram of assembling a fixed end and a core drill rod provided by an embodiment of the present invention;

[0030] Figure 7 It is a schematic diagram of assembling another fixed end and a core drill rod provided by an embodiment of the present invention;

[0031] Figure 8 is a schematic diagram of signal transmission provided by an embodiment of the present invention;

[0032] Fig. 9 It is a flow chart of the method provided by an embodiment of the present invention.

[0033] In the figure: 1-core drilling rig; 2-core drill rod; 21-inner wall; 22-outer wall; 3-tightening device; 31-tightening pipe fitting; 311-fixed end; 312-clamping end; 313-bearing; 314-retaining ring; 315-contraction groove; 316-wiring groove; 317-anti-slip pad; 32-steel strand; 4-hydraulic jack; 5-vibrating string dynamometer; 6-data acquisition instrument; 7-working platform; 71-drilling hole; 8-reaction plate. DETAILED DESCRIPTION

[0034] In order to make the objectives, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0035] Figure 1 is a schematic diagram of the overall structure of the device provided by an embodiment of the present invention; Figure 2 It is a schematic diagram of the assembly structure of a core drill rod and a clamping device provided in an embodiment of the present invention; Figure 3 It is a schematic cross-sectional view of the assembly of a core drill rod and a clamp pipe provided by an embodiment of the present invention; Figure 4 The embodiment of the present invention provides Figure 3 A schematic diagram of the enlarged structure at point A; Figure 5 is a schematic cross-sectional view of a clamp pipe fitting provided by an embodiment of the present invention; Figure 6 It is a schematic diagram of assembling a fixed end and a core drill rod provided by an embodiment of the present invention; Figure 7 It is a schematic diagram of assembling another fixed end and a core drill rod provided by an embodiment of the present invention; Figure 8 is a schematic diagram of signal transmission provided by an embodiment of the present invention; Fig. 9 is a flow chart of the method provided by an embodiment of the present invention. Figures 1 to 9 The device shown is used for in-situ pull-out test of underwater rock mass, comprising: a core drill rig 1, a core drill rod 2, a clamping device 3, a hydraulic jack 4, a vibrating-string dynamometer 5 and a data acquisition instrument 6. The core drill rig 1 is used to control the core drill rod 2 to move or rotate to drill the target rock mass. The core drill rod 2 is a cylindrical structure with openings at both ends. The core drill rod 2 is vertically arranged. The top of the core drill rod 2 is connected to the core drill rig 1. The clamping device 3 is arranged at one end of the core drill rod 2 close to the bottom. The clamping device 3 is used to lock the drilled target rock mass. The hydraulic jack 4 and the vibrating-string dynamometer 5 are sleeved on the core drill rod 2. The hydraulic jack 4 is used to provide a pull-out force to the core drill rod 2. The vibrating-string dynamometer 5 is used to measure the pull-out force of the hydraulic jack 4. The data acquisition instrument 6 is connected to the signal of the vibrating-string dynamometer 5 to calculate the tensile strength of the target rock mass based on the pull-out force.

[0036] Exemplarily, in an embodiment of the present invention, the core drill rig 1 can control the lifting, horizontal and rotational movements of the core drill rod 2. The device is transported above the water surface of the rock mass to be tested, and the core drill rod 2 is controlled by the core drill rig 1 to drill the target rock mass underwater. At this time, the target rock mass is located inside the core drill rod 2, and one end of the target rock mass is still connected to the underwater rock formation. At this time, the core drill rod 2 is clamped and fixed with the tightening device 3, and then the core drill rod 2 is provided with a pulling force by the hydraulic jack 4 until the target rock mass is broken. During the pulling process, the pulling force data provided by the hydraulic jack 4 is measured by the vibrating string dynamometer 5, and finally the pulling force data measured by the vibrating string dynamometer 5 is collected and recorded by the data acquisition instrument 6, and the tensile strength of the target rock mass is calculated. The calculation formula for the tensile strength of the rock mass is:

[0037] R t =(P max -P) / A (1),

[0038] Where: R t is the tensile strength of rock mass,

[0039] P max is the peak value of the dynamometer,

[0040] P is the measured value after breaking.

[0041] A is the fracture surface area.

[0042] Among them, the fracture surface area is not necessarily a horizontal plane. When the angle between the fracture surface and the horizontal plane is θ, the fracture surface area is:

[0043] A=πr 2 / cosθ (2),

[0044] Where: r is the radius of the reef limestone column.

[0045] The peak value of the dynamometer is the maximum pull-out force, which is measured by a vibrating-wire dynamometer 5. The measured value after breaking is the gravity of the device, the gravity of the rock column in the tube, and the frictional resistance minus the buoyancy, all of which are known quantities. When an irregular fracture occurs, the fracture area can be calculated by coring.

[0046] The embodiment of the present invention provides a device and method for in-situ pull-out test of underwater rock mass. The core drill rod 2 is controlled by a core drill rig 1 to drill the target rock mass underwater, and then the drilled target rock mass and the core drill rod 2 are fixed by a clamp device 3. Then, a pull-out force is provided to the core drill rod 2 by a hydraulic jack 4 until the target rock mass is broken. During the pull-out, the pull-out force data provided by the hydraulic jack 4 is measured by a vibrating-wire dynamometer 5. Finally, the pull-out force data measured by the vibrating-wire dynamometer 5 is collected and recorded by a data acquisition instrument 6, and the tensile strength of the target rock mass is calculated. The device provided by the embodiment of the present invention does not need to transport the target rock mass to a laboratory after taking it out for pull-out test. After drilling the target rock mass underwater, the pull-out test is directly performed in the in-situ environment. The device and method can eliminate the influence of the time delay caused by transporting the rock mass on the test results, and can effectively solve the problem of low accuracy of pull-out test data in the prior art.

[0047] Optionally, the core drill rod 2 includes an inner wall 21 and an outer wall 22, an annular space is set between the inner wall 21 and the outer wall 22, the distance between the inner wall 21 and the outer wall 22 near the bottom of the core drill rod 2 gradually decreases, the tightening device 3 is a cylindrical structure, and is slidably arranged in the annular space, the tightening device 3 includes a tightening pipe 31 and a steel strand 32, the tightening pipe 31 includes a fixed end 311, a clamping end 312 and a bearing 313, the fixed end 311 is arranged above the clamping end 312, the fixed end 311 and the clamping end 312 are connected by a bearing 313, the fixed end 311 matches the inner wall 21 and the outer wall 22 at the bottom end of the core drill rod 2, the steel strand 32 is spirally wound on the tightening pipe 31, one end of the steel strand 32 is fixed on the fixed end 311, and the other end is fixed on the clamping end 312.

[0048] Illustratively, in an embodiment of the present invention, the other end of the steel strand 32 is fixed to the bottom of the clamping end 312, so as to better contract the clamping end. The clamping device 3 needs to clamp and fix the target rock mass after drilling, so as to facilitate the subsequent pulling and breaking test of the target rock mass. In this embodiment, the clamping device 3 uses a clamping pipe 31 and a steel strand 32 to fix the target rock mass. When the core drill rod 2 drills the target rock mass, the clamping pipe 31 is located between the inner wall 21 and the outer wall 22 of the core drill rod 2 and does not contact the target rock mass. When the drilling is completed, the rotation of the core drill rod 2 is stopped, and the core drill rod 2 is lifted upward. At this time, due to the action of gravity, the clamping pipe 31 falls out of the core drill rod 2, as shown in FIG. Figure 6 As shown, the inner wall 21 and the outer wall 22 of the bottom end of the core drill rod 2 are trapezoidal structures, and the top part of the fixed end 311 is a trapezoidal structure matching the bottom end of the core drill rod 2. The solid-line trapezoidal structure in the figure is the state when the fixed end 311 is about to contact the core drill rod 2, and the fixed end 311 and the core drill rod 2 are not locked at this time. The dotted-line trapezoidal structure in the figure is the state when the fixed end 311 slides downward to contact the inner wall 21 and the outer wall 22 at the same time, and the fixed end 311 and the core drill rod 2 are locked. When the fixing end 311 is in contact with the bottom end of the core drill rod 2, the fixing end 311 is engaged with the core drill rod 2, so that the fixing end 311 will not fall out of the core drill rod 2 completely, and the fixing end 311 is fixed to the core drill rod 2. At this time, the core drill rod 2 is controlled to rotate so that the fixing end 311 rotates together with the core drill rod 2. Under the action of the bearing 313, the fixing end 311 and the clamping end 312 rotate and separate. The initial state of the steel strand 32 is a loose state. When the core drill rod 2 rotates, since one end of the steel strand 32 is fixed on the fixing end 311 and the other end is fixed on the clamping end 312, the steel strand 32 will be locked and provide a winding locking force to the clamping end 312, so that the target rock mass in the clamping end 312 is fixed in the clamping end 312. At this time, the locking of the target rock mass by the fixing device 3 is completed. The target rock mass is locked by this structure, which is easy to operate without setting up another clamping device. The original rotational force of the core drill 1 can be used to lock the steel strand 32 to the target rock mass, thereby improving the convenience of operation of the device.

[0049] Optionally, a clamping ring 314 is sleeved on the top of the fixed end 311 , and the clamping ring 314 matches the inner wall 21 and the outer wall 22 of the bottom end of the core drill rod 2 .

[0050] For example, in an embodiment of the present invention, Figure 7As shown, when a retaining ring 314 is sleeved on the fixed end 311, the inner wall 21 and the outer wall 22 at the bottom end of the core drill rod 2 are trapezoidal structures, and the inner wall of the fixed end 311 is an equal-width structure. The solid-line rectangular structure in the figure is the state when the fixed end 311 is about to contact the core drill rod 2, and the fixed end 311 and the core drill rod 2 are not locked at this time. The dotted-line trapezoidal structure in the figure is the state when the fixed end 311 slides downward to contact the inner wall 21 and the outer wall 22 at the same time, and the fixed end 311 and the core drill rod 2 are locked. By setting the retaining ring 314, the shape of the fixed end 311 can be changed, so that the inner wall thickness changes from unequal to equal wall thickness, which is simpler during production and manufacturing, and reduces production costs. At the same time, the retaining ring 314 is frictionally fixed to the core drill rod 2. When the retaining ring 314 is damaged by friction, it only needs to replace the retaining ring 314 to ensure the normal operation of the device. Compared with the fixed end 311 directly frictionally fixed to the core drill rod 2, the use of the retaining ring 314 increases the service life of the device.

[0051] Optionally, the clamping ring 314 is made of wear-resistant steel.

[0052] For example, in the embodiment of the present invention, the wear-resistant steel has the characteristics of wear resistance and high hardness, and because the wear-resistant steel contains a large amount of chromium, it has excellent corrosion resistance and there is no need to worry about corrosion. Although the price of wear-resistant steel is one to two times that of ordinary steel, its service life far exceeds that of ordinary steel, and its cost performance is relatively high. Wear-resistant steel has strong weldability and can be easily bent into various shapes, which is very convenient to process. By setting the clamping ring 314 as a wear-resistant steel part, the service life of the device can be further improved.

[0053] Optionally, the clamping end 312 is provided with a contraction groove 315 along the length direction.

[0054] Illustratively, in an embodiment of the present invention, a shrinkage groove 315 is provided along the length direction of the clamping end 312, so that when the steel strand 32 applies a locking force to the clamping pipe 31, the clamping end 312 can be easily deformed and tightened, so that the clamping end 312 can better clamp and lock the target rock mass, thereby preventing slipping due to insufficient locking force when the hydraulic jack 4 applies a pulling force, thereby improving the stability of the device.

[0055] Optionally, a plurality of contraction grooves 315 are provided, and the plurality of contraction grooves 315 are evenly distributed along the circumference of the clamping pipe 31 .

[0056] Illustratively, in an embodiment of the present invention, by providing a plurality of shrinkage grooves 315, it can further facilitate the steel strand 32 to shrink and deform the clamping end 312 when a locking force is applied to the clamping pipe 31, so that the clamping end 312 can more stably clamp and lock the target rock mass therein, thereby further improving the stability of the device.

[0057] Optionally, a wiring groove 316 matching the steel strand 32 is provided on the clamping pipe 31 .

[0058] Exemplarily, in an embodiment of the present invention, a plurality of wiring grooves 316 are opened along the length direction of the clamping pipe 31, and the plurality of wiring grooves 316 are evenly spaced. By setting the wiring grooves 316, the steel strand 32 can be set in the wiring grooves 316, so that when the steel strand 32 is not subjected to force, it will not be entangled due to looseness. When subjected to force, the steel strand 32 can be limited by the wiring grooves 316 to prevent the steel strand 32 from applying uneven locking force to the clamping end 312, so that the steel strand 32 can provide a more stable locking force to the clamping end 312, thereby further improving the stability of the device.

[0059] Optionally, an anti-slip pad 317 is provided on the inner side wall of the clamping end 312 .

[0060] For example, in the embodiment of the present invention, by providing the anti-skid pad 317, on the one hand, the clamping end 312 can be prevented from slipping when clamping the target rock mass, thereby further improving the stability of the device. On the other hand, the target rock mass can be prevented from wearing the inner wall of the clamping end 312, thereby further improving the service life of the device.

[0061] Optionally, it also includes a working platform 7 and a reaction plate 8, the working platform 7 is provided with a borehole 71, the core drill rod 2 is inserted into the borehole 71, the vibrating string dynamometer 5 is arranged on the working platform 7, the hydraulic jack 4 is arranged on the vibrating string dynamometer 5, and the reaction plate 8 is arranged between the hydraulic jack 4 and the vibrating string dynamometer 5.

[0062] Exemplarily, in an embodiment of the present invention, the core drilling rig 1 is disposed on a working platform 7, which is a platform relatively fixed to the land. A borehole 71 is opened on the working platform 7, and the borehole 71 is connected to the water body. The core drill rod 2 is passed through the borehole 71 to drill the target rock mass underwater. The vibrating string dynamometer 5 is disposed on the working platform 7, and the hydraulic jack 4 is disposed on the vibrating string dynamometer 5. When the hydraulic jack 4 works to apply a supporting force, the supporting force is transmitted to the vibrating string dynamometer 5 and acts on the working platform 7. The reaction force applied by the working platform 7 causes the core drill rod 2 to move upward to provide a pulling force to the target rock mass. By arranging a reaction plate 8 between the hydraulic jack 4 and the vibrating string dynamometer 5, the data measured by the vibrating string dynamometer 5 can be more accurate.

[0063] A method for in-situ pull-out testing of underwater rock mass, comprising the aforementioned device for in-situ pull-out testing of underwater rock mass, comprises the following steps:

[0064] S1: The core drilling rig 1 controls the core drill rod 2 to drill the target rock underwater.

[0065] Specifically, in an embodiment of the present invention, the core drilling rig 1 is set on a working platform 7, which is a platform fixed relatively to the land. A borehole 71 is opened on the working platform 7, and the borehole 71 is connected to the water body. The vibrating string dynamometer 5, the reaction plate 8, and the hydraulic jack 4 are arranged in advance around the borehole 71 from bottom to top, and the core drill rod 2 passes through the hydraulic jack 4, the reaction plate 8, the vibrating string dynamometer 5, and the borehole 71 in sequence, and the underwater target rock mass is drilled.

[0066] S2: Fix the target rock mass to be drilled and the core drill rod 2 by means of the clamp device 3.

[0067] Specifically, in an embodiment of the present invention, after the drilling process of the core drill rod 2 is completed, the rotation of the core drill rod 2 is stopped and the core drill rod 2 is lifted upward. At this time, due to the action of gravity, the clamping pipe 31 falls out of the core drill rod 2 until the fixed end 311 of the clamping pipe 31 is attached to and locked with the core drill rod 2. By starting the core drilling rig 1 to rotate, the fixed end 311 rotates together with the core drill rod 2, driving the steel strand 32 to contract and clamp the clamping end 312, so that the target rock mass located inside the clamping pipe 31 is fixedly clamped in the clamping pipe 31, that is, the target rock mass and the core drill rod 2 are fixed.

[0068] S3: providing a pulling force to the core drill rod 2 through the hydraulic jack 4 until the target rock mass is broken, during which the pulling force data provided by the hydraulic jack 4 is measured by the vibrating-wire dynamometer 5 .

[0069] Specifically, in an embodiment of the present invention, after the target rock mass and the core drill rod 2 are fixed, the supporting force is provided by starting the hydraulic jack 4, so that the supporting force is transmitted to the vibrating-wire dynamometer 5 and acts on the working platform 7. The reaction force applied by the working platform 7 causes the core drill rod 2 to move upward to provide a pulling force to the target rock mass, and the moving stroke of the hydraulic jack 4 is continuously increased until the target rock mass is broken.

[0070] S4: The pull-out force data measured by the vibrating-wire dynamometer 5 is collected and recorded by the data acquisition device 6, and the tensile strength of the target rock mass is calculated.

[0071] Specifically, in the embodiment of the present invention, during the pulling of the target rock mass, the pulling force data provided by the hydraulic jack 4 is measured by the vibrating-wire dynamometer 5, and finally the pulling force data measured by the vibrating-wire dynamometer 5 is collected and recorded by the data acquisition instrument 6, and the tensile strength of the target rock mass is calculated by the calculation formula (1).

[0072] Unless otherwise defined, the technical terms or scientific terms used herein shall have the usual meanings understood by persons of ordinary skill in the field to which the present invention belongs. The words "first", "second" and similar words used in the patent application specification and claims of the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "one" or "one" do not indicate a quantity limitation, but indicate the existence of at least one. Words such as "include" or "comprise" and similar words mean that the elements or objects appearing before "include" or "comprise" include the elements or objects listed after "include" or "comprise" and their equivalents, and do not exclude other elements or objects. Words such as "connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0073] The above descriptions are merely optional embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A device for in-situ pull-out testing of underwater rock mass, characterized in that: include: A core drilling machine (1), a core drilling rod (2), a clamping device (3), a hydraulic jack (4), a vibrating wire dynamometer (5) and a data acquisition instrument (6), The core drilling rig (1) is used to control the core drilling rod (2) to move or rotate to drill a target rock mass. The core drilling rod (2) is a cylindrical structure with two ends open. The core drilling rod (2) is vertically arranged. The top of the core drilling rod (2) is connected to the core drilling rig (1). The clamping device (3) is arranged at one end of the core drilling rod (2) close to the bottom. The clamping device (3) is used to lock the drilled target rock mass. The hydraulic jack (4) and the vibrating string dynamometer (5) are sleeved on the core drilling rod (2). The hydraulic jack (4) is used to provide a pulling force to the core drilling rod (2). The vibrating string dynamometer (5) is used to measure the pulling force of the hydraulic jack (4). The data acquisition instrument (6) is connected to the signal of the vibrating string dynamometer (5) to calculate the tensile strength of the target rock mass based on the pulling force.

2. The device for in-situ pull-out testing of underwater rock mass according to claim 1, characterized in that: The core drill rod (2) comprises an inner wall (21) and an outer wall (22), an annular space is arranged between the inner wall (21) and the outer wall (22), the distance between the inner wall (21) and the outer wall (22) close to the bottom of the core drill rod (2) gradually decreases, the clamping device (3) is a cylindrical structure, and is slidably arranged in the annular space, the clamping device (3) comprises a clamping pipe (31) and a steel strand (32), the clamping pipe (31) comprises a fixed end (311), a clamping end (312) and a bearing (313), the fixed end (311) is arranged above the clamping end (312), the fixed end (311) and the clamping end (312) are connected via the bearing (313), the fixed end (311) matches the inner wall (21) and the outer wall (22) at the bottom end of the core drill rod (2), the steel strand (32) is spirally wound on the clamping pipe (31), one end of the steel strand (32) is fixed on the fixed end (311), and the other end is fixed on the clamping end (312).

3. The device for in-situ pull-out testing of underwater rock mass according to claim 2, characterized in that: A clamping ring (314) is sleeved on the top of the fixed end (311), and the clamping ring (314) matches the inner wall (21) and the outer wall (22) at the bottom end of the core drill rod (2).

4. The device for in-situ pull-out testing of underwater rock mass according to claim 3, characterized in that: The clamping ring (314) is made of wear-resistant steel.

5. The device for in-situ pull-out testing of underwater rock mass according to claim 2, characterized in that: The clamping end (312) is provided with a contraction groove (315) along the length direction.

6. The device for in-situ pull-out testing of underwater rock mass according to claim 5, characterized in that: A plurality of contraction grooves (315) are provided, and the plurality of contraction grooves (315) are evenly distributed along the circumference of the clamping pipe (31).

7. The device for in-situ pull-out testing of underwater rock mass according to claim 2, characterized in that: The clamping pipe (31) is provided with a wiring groove (316) matching the steel strand (32).

8. The device for in-situ pull-out testing of underwater rock mass according to claim 2, characterized in that: An anti-slip pad (317) is provided on the inner side wall of the clamping end (312).

9. The device for in-situ pull-out testing of underwater rock mass according to claim 1, characterized in that: The invention also comprises a working platform (7) and a reaction plate (8), wherein a borehole (71) is provided on the working platform (7), the core drill rod (2) is inserted into the borehole (71), the vibrating-wire dynamometer (5) is arranged on the working platform (7), the hydraulic jack (4) is arranged on the vibrating-wire dynamometer (5), and the reaction plate (8) is arranged between the hydraulic jack (4) and the vibrating-wire dynamometer (5).

10. A method for in-situ pull-out testing of underwater rock mass, comprising the device for in-situ pull-out testing of underwater rock mass according to claims 1 to 9, characterized in that: The following steps are involved: Step 1: using the core drilling machine (1) to control the core drilling rod (2) to drill the target rock mass underwater; Step 2: fixing the drilled target rock mass and the core drill rod (2) by means of the clamping device (3); Step 3: providing a pulling force to the core drill rod (2) by means of the hydraulic jack (4) until the target rock mass is broken, during which the pulling force data provided by the hydraulic jack (4) is measured by means of the vibrating wire dynamometer (5); Step 4: The pull-out force data measured by the vibrating-wire dynamometer (5) is collected and recorded by the data acquisition instrument (6), and the tensile strength of the target rock mass is calculated.

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