Indoor anchoring part manufacturing method

Abstract

The invention discloses an indoor anchoring part manufacturing method, and particularly relates to the technical field of anchoring parts, the indoor anchoring part manufacturing method comprises the following steps: step 1, selecting a rock material, and manufacturing a shaped rock sample block or a fissure-shaped rock sample block; 2, measuring and calculating the uniaxial saturated compressive strength Rc of the rock and the longitudinal wave velocity vpr of the rock; 3, applying confining pressure to the fissure-shaped rock sample block, simulating an initial crustal stress state, then carrying out wave velocity measurement on the fissure-shaped rock sample block to obtain a rock mass longitudinal wave velocity vpm, and calculating a surrounding rock basic grading index BQ value; fourthly, anchor holes are drilled; and 5, fixing the anchor rod with the shaped rock sample block or the fissure-shaped rock sample block through an anchoring agent. The device can accurately reproduce anchor rod supporting operation under different surrounding rock conditions indoors, effectively solves the problems that in the prior art, a test piece does not accord with an actual project, and the reliability of a test result is low, and provides a test basis closer to engineering practice for anchor rod mechanical property evaluation.

Description

Technical Field

[0001] This invention relates to the field of anchor technology, and in particular to a method for manufacturing indoor anchors. Background Technology

[0002] In tunnel construction, anchor bolts, as core components for surrounding rock reinforcement, directly affect the safety and stability of the project due to their mechanical properties. Anchor bolt pull-out tests are a crucial means of evaluating anchor bolt anchoring effectiveness and load-bearing capacity, currently relying heavily on field tests. However, field tests are significantly limited by factors such as complex geological structures, extreme weather conditions, and interference from overlapping construction projects. On the one hand, tests require substantial investment of manpower, resources, and time; each test is lengthy and difficult to repeat, hindering the need for rapid design optimization. On the other hand, the uncontrollability of the field environment leads to large data dispersion, making results from different working conditions incomparable and restricting the standardized development of anchor bolt support technology.

[0003] With the development of indoor testing technology, obtaining stable data through artificially controlled experimental conditions has become a current research trend. However, existing indoor anchor fabrication methods have significant drawbacks. On the one hand, the fabrication process is severely disconnected from on-site construction. For example, concrete is often used to replace real rock as the specimen material, and the drilling process differs significantly from actual engineering practices. This makes it impossible for the specimens to realistically simulate the stress state of anchor bolts in complex surrounding rock. On the other hand, existing methods lack quantitative characterization of surrounding rock conditions and struggle to simulate the support conditions of anchor bolts under common on-site conditions with varying rock integrity. This leads to a disconnect between experimental results and actual engineering conditions, failing to provide effective guidance for engineering design.

[0004] As tunnel engineering continues to expand into deeper and more complex geological areas, there is an urgent need for an indoor anchor solid specimen preparation method that can accurately simulate the entire on-site construction process and include quantitative analysis of surrounding rock conditions based on on-site geological surveys. This would allow for a deep alignment between test results and actual engineering conditions, providing a solid scientific basis for the safe design and efficient construction of tunnel engineering. Summary of the Invention

[0005] The purpose of this invention is to provide an indoor anchor manufacturing method to solve the problems existing in the prior art. It can accurately reproduce anchor support operations under different surrounding rock conditions indoors, effectively solving the problems of discrepancies between test specimens and actual engineering and low reliability of test results in the prior art, and providing test basis that is closer to engineering practice for the evaluation of anchor mechanical performance.

[0006] To achieve the above objectives, the present invention provides the following solution:

[0007] This invention provides a method for manufacturing indoor anchors, comprising the following steps:

[0008] Step 1: Select rock material and process it to the specified dimensions according to the test requirements to obtain a complete rock sample; or select rock material, process it to the specified dimensions according to the test requirements, and create fissures to obtain a fissure-shaped rock sample.

[0009] Step 2: Calculate the uniaxial saturated compressive strength R of the rock. c and the longitudinal wave velocity v of the rock block pr ;

[0010] Step 3: Apply confining pressure to the fractured rock sample to simulate the initial in-situ stress state. Symmetrically arrange multiple pairs of measuring points on the two opposite end faces of the fractured rock sample where no confining pressure is applied. Measure the wave velocity at these multiple pairs of measuring points using a non-metallic ultrasonic testing instrument. Average all wave velocities to obtain the average wave velocity value, which is the longitudinal wave velocity v of the rock mass. pm Calculate the rock mass integrity index K v And the basic classification index BQ value of surrounding rock;

[0011] Step 4: Drill anchor holes in the intact rock sample or the fractured rock sample;

[0012] Step 5: Insert the anchor rod into the anchor hole and fix the anchor rod to the intact rock sample block or the fractured rock sample block using an anchoring agent.

[0013] Preferably, in step one, the rock is processed into a rectangular rock sample block of 260mm×260mm×600mm.

[0014] Preferably, in step three, multiple pairs of measuring points are evenly distributed in the confining pressure stress area on the two end faces where no confining pressure is applied.

[0015] Preferably, the line connecting each pair of measuring points is parallel to the axis of the cuboid rock sample.

[0016] Preferably, each of the measuring points is coated with a coupling agent such as butter or petroleum jelly.

[0017] Preferably, in step four, a horizontal bench drill is used to drill holes in the intact rock sample or the fractured rock sample.

[0018] Preferably, the processed intact rock sample or the fractured rock sample is placed on the stone holder at the tail of the horizontal bench drill, the horizontal bench drill is started, and the intact rock sample or the fractured rock sample is drilled according to the designed hole diameter and hole depth until the predetermined drilling parameter standard is reached.

[0019] Preferably, before drilling the fractured rock sample, a steel mold matching the size of the fractured rock sample is fitted over the fractured rock sample.

[0020] Preferably, in step five, the anchoring agent is first filled into the anchor hole, and then the anchor rod is connected to the pneumatic wrench. After the anchor rod is inserted into the anchor hole, the pneumatic wrench is used to drive the anchor rod to rotate and stir the anchoring agent.

[0021] Preferably, the end of the anchor rod away from the pneumatic wrench is connected to the stirring blade.

[0022] The present invention achieves the following technical effects compared to the prior art:

[0023] This invention provides a method for manufacturing indoor anchors, using rock materials instead of concrete to create sample blocks. By processing intact or fractured rock samples, the method directly simulates the intact or fractured state of the actual surrounding rock, avoiding differences in mechanical properties caused by material substitution and effectively enhancing the guiding value of the test results for engineering practice. By applying confining pressure laterally, the method simulates the triaxial geostress environment of the rock sample underground, making the rock sample closer to the actual stress state of the engineering rock mass, thus improving the reliability and engineering applicability of the test results. The longitudinal wave velocity v of the rock mass is obtained by averaging multiple wave velocity measurements. pm This technology enables quantitative evaluation of rock mass integrity indoors, solving the problem of discrepancies between specimens and actual rock masses in traditional indoor tests. It provides rock mass models and parameters that are closer to real engineering conditions, and can accurately reproduce anchor bolt support operations under different surrounding rock conditions indoors. It effectively solves the problems of discrepancies between specimens and actual engineering and low reliability of test results in existing technologies, providing a more practical test basis for evaluating the mechanical performance of anchor bolts. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 A flowchart for the method of manufacturing indoor anchors;

[0026] Figure 2 The longitudinal wave velocity v of the rock mass pm Flowchart;

[0027] Figure 3 This is a distribution map of the relative positions of the measuring points. Detailed Implementation

[0028] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] The purpose of this invention is to provide an indoor anchor manufacturing method to solve the problems existing in the prior art. It can accurately reproduce anchor support operations under different surrounding rock conditions indoors, effectively solving the problems of discrepancies between test specimens and actual engineering and low reliability of test results in the prior art, and providing test basis that is closer to engineering practice for the evaluation of anchor mechanical performance.

[0030] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0031] This invention provides a method for manufacturing indoor anchors, such as... Figures 1-2 As shown, it includes the following steps:

[0032] Step 1: Select rock material and process it to the specified dimensions according to the test requirements to obtain a complete rock sample; or select rock material, process it to the specified dimensions according to the test requirements, and create fissures to obtain a fissure-shaped rock sample.

[0033] Step 2: Calculate the uniaxial saturated compressive strength R of the rock according to the engineering rock mass testing method standard. c The longitudinal wave velocity v of a cylindrical rock sample with a diameter of 50 mm and a height of 100 mm was obtained by ultrasonic testing. pr ;

[0034] Step 3: Apply confining pressure to the fractured rock sample using the confining pressure loading mechanism of an anchor pull-out test device (publication number CN120445847A). Apply the confining pressure value corresponding to the required experimental conditions to establish the initial in-situ stress state. Symmetrically arrange multiple pairs of measuring points on two opposite end faces where no confining pressure is applied. Measure the wave velocity at these points using a non-metallic ultrasonic testing instrument. Place the two probes of the non-metallic ultrasonic testing instrument at a pair of measuring points on each of the two opposite end faces and read the wave velocity value for each pair. Average all wave velocity values ​​to obtain the average wave velocity value, which is the longitudinal wave velocity v of the fractured rock sample. pm Longitudinal wave velocity v of rock mass pm Combined with the longitudinal wave velocity v of the rock block pr Calculate the rock mass integrity index K v Rock mass integrity index K vWith uniaxial saturated compressive strength R c The basic grading index BQ value of the surrounding rock is calculated using a formula; it should be noted that the longitudinal wave velocity v of the intact rock sample is... pm It can be identified as being related to the longitudinal wave velocity v of the rock block. pr Equal, that is, the rock mass integrity index K of the intact rock sample block. v The value is 1.

[0035] The formulas involved in step three are as follows:

[0036] BQ = 100 + 3R c +250K v

[0037]

[0038] Where: BQ - basic classification index of surrounding rock;

[0039] R c - Uniaxial saturated compressive strength (MPa);

[0040] K v - Rock mass integrity index;

[0041] v pm -Rock mass longitudinal wave velocity (m / s);

[0042] v pr -P-wave velocity of rock block (m / s).

[0043] It should be noted that when applying confining pressure to the rock sample using the anchor pull-out test device, localized fragmentation may sometimes occur on the side surface of the rock sample. This results in unevenness on the side surface, affecting the measurement work. In this case, it is only necessary to manually apply a small amount of cement mortar, controlling the thickness to 2-4 mm, and appropriately piece the fragmented pieces back into their original positions to form a complete side surface before resuming the measurement. Experiments show that the impact of a small amount of cement mortar on the wave velocity measurement value is no more than 10%, and its impact on the final indoor grading is negligible.

[0044] Step 4: Drill anchor holes in intact or fractured rock samples;

[0045] Step 5: Insert the anchor rod into the anchor hole and fix the anchor rod to the intact rock sample block or to the fractured rock sample block using the anchoring agent.

[0046] Using rock instead of concrete to create sample blocks, and processing either intact or fractured rock samples, directly simulates the intact or fractured state of the actual surrounding rock. This avoids differences in mechanical properties caused by material substitution and effectively enhances the guiding value of the test results for engineering practice. When creating fractured rock samples, existing force-applying devices are used to slowly apply lateral and vertical pressures to the intact rock samples. For example, the confining pressure loading mechanism of an anchor pull-out test device (publication number CN120445847A) is used to apply confining pressure to the rock sample. When the pressure reaches the critical failure strength of the rock, natural fractures are generated inside the rock sample and gradually expand and connect, forming a fracture network structure similar to the fractured surrounding rock at a tunnel construction site, thus forming a fractured rock sample. Compared to traditional artificial fracture-creating methods, the fracture distribution, density, and opening characteristics generated by applying confining pressure to the rock sample through the anchor pull-out test device are closer to the actual geological conditions, effectively enhancing the guiding value of the test results for engineering practice.

[0047] By applying confining pressure laterally, the triaxial geostress environment of the rock sample underground was effectively simulated, making the sample closer to the actual stress state of the engineering rock mass, thus significantly improving the reliability and engineering applicability of the test results. Simultaneously, by symmetrically arranging multiple sets of measuring points on the sample end face and measuring wave velocity, the average value was taken as the longitudinal wave velocity v of the rock mass. pm This method enables quantitative evaluation of rock mass integrity, overcoming the problem that traditional indoor tests involve overly idealized specimens that do not match the actual state of the rock mass on site. It constructs a rock mechanics model and parameter system that is closer to real engineering conditions. This method can accurately reproduce the anchor bolt support process under different surrounding rock conditions indoors, effectively solving the technical bottleneck of low reliability of test results due to insufficient representativeness of specimens in existing technologies. It provides a more scientific, reliable and practical test basis for evaluating the mechanical performance of anchor bolts.

[0048] In a further preferred embodiment of the present invention, in step one, the rock is processed into a rectangular rock sample block of 260mm×260mm×600mm.

[0049] In a further preferred embodiment of the present invention, in step three, as follows: Figure 3 As shown, multiple pairs of measuring points are evenly distributed in the confining pressure stress zone on the two 260mm×260mm end faces where no confining pressure is applied. The location of the measuring points within the confining pressure stress zone and as close as possible to the borehole location can better reflect the "geological conditions" near the anchor hole.

[0050] In a further preferred embodiment of the present invention, the line connecting each pair of measuring points is parallel to the axis of the cuboid rock sample block.

[0051] In a further preferred embodiment of the present invention, each measuring point is coated with a coupling agent such as butter or petroleum jelly, which can eliminate air between the probe of the non-metallic ultrasonic testing instrument and the contact surface of the rock sample, thus ensuring the accuracy of the wave velocity measurement.

[0052] In a further preferred embodiment of the present invention, in step four, a horizontal benchtop water drill is used to drill holes in either a intact or fractured rock sample. The prepared intact or fractured rock sample is placed on a stone holder at the tail of the horizontal benchtop water drill. The stone holder is installed at the tail of the drill platform to facilitate drilling the sample at a predetermined position, ensuring the horizontality of the hole. The horizontal benchtop water drill is then started, and it drills horizontally forward along a predetermined track, drilling the intact or fractured rock sample according to the designed hole diameter and depth until the predetermined drilling parameters are met. The width of the stone holder needs to be compatible with the width of the rock sample; and a gap is reserved at the bottom of the stone holder to facilitate lifting with ropes, ensuring the convenience of fixing and transporting the rock sample.

[0053] In a further preferred embodiment of the present invention, before drilling the fractured rock sample, when transporting the fractured rock sample to the stone-holding frame using a crane, the top plate of the sample delivery trolley in an anchor pull-out test device (publication number CN120445847A) is used as a sample tray. During the hoisting process, the fractured rock sample and the tray are hoisted as a whole to avoid damage to the broken sample due to collision and shaking during separate transportation. Because of the strong impact force of water drilling, the fractured rock sample is easily disturbed, leading to sample breakage and inability to form a hole. Therefore, a steel mold matching the size of the fractured rock sample is placed over the fractured rock sample. The steel mold applies a simple rigid constraint to the fractured rock sample, which can resist the drilling impact force, significantly improve the hole formation rate, and effectively avoid sample damage.

[0054] In a further preferred embodiment of the present invention, in step five, the anchoring agent is first filled into the anchor hole, and then the anchor rod is connected to a pneumatic wrench. After the anchor rod is inserted into the anchor hole, the pneumatic wrench is used to rotate the anchor rod and stir the anchoring agent. The anchor rod is connected to the pneumatic wrench through a connecting sleeve, and a stirring blade is connected to the end of the anchor rod away from the pneumatic wrench. Due to the large weight of the pneumatic wrench, a gantry crane is used to assist in lifting the pneumatic wrench. The pneumatic wrench is started, and the rotational driving force generated by the pneumatic wrench is used to gradually drill the anchor rod into the anchor hole. During the drilling process, the drilling speed, force, and stirring time are strictly controlled to ensure that the anchor rod is accurately anchored in the rock sample according to the design requirements. After the anchoring agent solidifies, the indoor anchor solid specimen is prepared.

[0055] This invention provides a complete chain simulation of indoor anchor fabrication, encompassing sample preparation, indoor geological exploration, drilling operations, and anchor installation. Real rock is used to fabricate samples of specific specifications. Through specialized equipment and processes, each step of the on-site anchor support process is replicated, ensuring seamless integration between the indoor testing process and actual construction, and guaranteeing the authenticity of the testing scenario. Furthermore, it breaks through the limitations of traditional indoor testing, which relies on a single, intact sample. It innovatively enables the fabrication of fragmented samples commonly found on construction sites, allowing for the repeated production of anchor specimens under different rock mass integrity conditions, such as intact or fractured rock blocks. For fractured rock blocks, a pressure-induced fracturing technique is employed to simulate the actual fracture development morphology. Simultaneously, innovative quantitative analysis methods are used, employing indoor rock mass wave velocity measurement to directly align with the basic grading standards of the surrounding rock on-site. This deeply correlates indoor test data with actual engineering geological conditions, significantly enhancing the engineering reference value of the test results.

[0056] Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention. Furthermore, those skilled in the art will recognize that, based on the ideas of this invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A method for manufacturing indoor anchors, characterized in that: Includes the following steps: Step 1: Select rock material and process it to the specified dimensions according to the test requirements to obtain a complete rock sample; or select rock material, process it to the specified dimensions according to the test requirements, and create fissures to obtain a fissure-shaped rock sample. Step 2: Calculate the uniaxial saturated compressive strength R of the rock. c and the longitudinal wave velocity v of the rock block pr ; Step 3: Apply confining pressure to the fractured rock sample to simulate the initial in-situ stress state. Symmetrically arrange multiple pairs of measuring points on the two opposite end faces of the fractured rock sample where no confining pressure is applied. Measure the wave velocity at these multiple pairs of measuring points using a non-metallic ultrasonic testing instrument. Average all wave velocities to obtain the average wave velocity value, which is the longitudinal wave velocity v of the rock mass. pm Calculate the rock mass integrity index K v And the basic classification index BQ value of surrounding rock; Step 4: Drill anchor holes in the intact rock sample or the fractured rock sample; Step 5: Insert the anchor rod into the anchor hole and fix the anchor rod to the intact rock sample block or the fractured rock sample block using an anchoring agent.

2. The method for manufacturing indoor anchors according to claim 1, characterized in that: In step one, the rock is processed into a rectangular rock sample block of 260mm×260mm×600mm.

3. The method for manufacturing indoor anchors according to claim 2, characterized in that: In step three, multiple pairs of measuring points are evenly distributed in the confining pressure stress zone on the two end faces where no confining pressure is applied.

4. The method for manufacturing indoor anchors according to claim 3, characterized in that: The line connecting each pair of measuring points is parallel to the axis of the rectangular rock sample.

5. The method for manufacturing indoor anchors according to claim 4, characterized in that: Each of the measurement points is coated with coupling agent butter or petroleum jelly.

6. The method for manufacturing indoor anchors according to claim 1, characterized in that: In step four, a horizontal bench drill is used to drill holes in the intact rock sample or the fractured rock sample.

7. The method for manufacturing indoor anchors according to claim 6, characterized in that: The processed intact rock sample or the fractured rock sample is placed on the stone holder at the tail of the horizontal bench drill. The horizontal bench drill is started, and the intact rock sample or the fractured rock sample is drilled according to the designed hole diameter and hole depth until the predetermined drilling parameter standard is reached.

8. The method for manufacturing indoor anchors according to claim 7, characterized in that: Before drilling the fractured rock sample, a steel mold matching the size of the fractured rock sample is fitted over the fractured rock sample.

9. The method for manufacturing indoor anchors according to claim 1, characterized in that: In step five, the anchoring agent is first filled into the anchor hole, and then the anchor rod is connected to the pneumatic wrench. After the anchor rod is inserted into the anchor hole, the pneumatic wrench is used to drive the anchor rod to rotate and stir the anchoring agent.

10. The method for manufacturing indoor anchors according to claim 9, characterized in that: The end of the anchor rod away from the pneumatic wrench is connected to the stirring blade.

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