A method for detecting the strength of an altered rock zone

Abstract

The present invention discloses a method for detecting the strength of an altered rock zone, which comprises the following steps: determining a plurality of altered rock zones to be measured, and selecting a plurality of representative rock zones from all the altered rock zones to be measured; marking a plurality of measurement points on each representative rock zone; using a penetration nail to penetrate each measurement point with the same kinetic energy to obtain the penetration depth of each measurement point, obtaining the average penetration depth of each representative rock zone and summarizing them to generate an average penetration depth statistical table; sampling each representative rock zone respectively, conducting a load test on the samples to obtain the compressive strength of each sample, and generating a statistical table of average penetration depth and compressive strength; fitting the average penetration depth and the compressive strength to obtain a conversion formula; and using the conversion formula to calculate according to the average penetration depth of the altered rock zone to be measured to obtain the compressive strength of the altered rock zone to be measured. It can solve the technical problems of the existing method for detecting the strength of an altered rock zone, such as complex process, long test period and high cost.

Description

Technical Field

[0001] The present invention relates to the technical field of geotechnical engineering, and particularly relates to a method for detecting the strength of altered rock zones. Background Art

[0002] The site geological conditions for water conservancy and hydropower projects are extremely complex. In projects with granite-like lithology, altered rock zones of different scales and properties generally exist. Altered rock zones with different strengths have different impacts on project construction, and different engineering treatment measures need to be taken for treatment. Therefore, the detection of the strength of altered rock zones is crucial.

[0003] The existing methods for detecting the strength of altered rock zones are mainly geotechnical mechanics tests, which mainly include in-situ tests and laboratory tests. Among them, in-situ tests require transporting test instruments to the site for testing, with high costs, high requirements for on-site rock detection conditions, and a long preparation time before the test; laboratory tests require sampling on-site rocks, protecting them, transporting them back to the laboratory, and then obtaining test results through a series of operations such as sample preparation and testing; both in-situ tests and laboratory tests have problems such as complex operation processes, high costs, long test cycles, and only being able to select typical specimens for testing. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for detecting the strength of altered rock zones, which can solve the technical problems of the existing methods for detecting the strength of altered rock zones, such as complex processes, long test cycles, and high costs.

[0005] The present invention is achieved through the following technical solutions:

[0006] A method for detecting the strength of altered rock zones includes the following steps:

[0007] Determine multiple altered rock zones to be measured, and select multiple representative rock zones from all the altered rock zones to be measured;

[0008] Mark multiple measurement points on each of the representative rock zones;

[0009] Obtain penetration nails, use the penetration nails to penetrate each measurement point with the same kinetic energy, obtain the penetration depth of each measurement point, and based on the penetration depths of all the measurement points of each representative rock zone, obtain the average penetration depth of each representative rock zone and summarize it to generate an average penetration depth statistical table;

[0010] Take samples from each of the representative rock zones respectively to obtain multiple samples, conduct load tests on the samples to obtain the compressive strength of each sample, and combine it with the average penetration depth statistical table to generate an average penetration depth and compressive strength statistical table;

[0011] According to the statistical table of the average penetration degree and the compressive strength, fit the average penetration degree and the compressive strength to obtain a conversion formula;

[0012] Using the conversion formula, calculate according to the average penetration degree of the to-be-detected altered rock zone to obtain the compressive strength of the to-be-detected altered rock zone.

[0013] Optionally, the step of selecting multiple representative rock zones from all the to-be-detected altered rock zones includes the following steps:

[0014] Conduct a geological survey on all the to-be-detected altered rock zones, and classify all the to-be-detected altered rock zones according to geological conditions;

[0015] Select one of the to-be-detected altered rock zones in each category as a representative rock zone.

[0016] Optionally, the geological conditions include any one or a combination of development scale, genetic mechanism, and mechanical properties.

[0017] Optionally, the step of marking multiple to-be-detected points on each of the representative rock zones includes the following steps:

[0018] Level each of the representative rock zones along the plumb plane;

[0019] Draw a detection line on each of the representative rock zones in the horizontal direction, so that both ends of the detection line intersect with the boundaries of the corresponding representative rock zones to form two intersection points;

[0020] Taking any one of the two intersection points as a starting point, mark multiple to-be-detected points along the detection line at a preset interval.

[0021] Optionally, the preset interval is 1.5 - 2 cm.

[0022] Optionally, the step of sampling on each of the representative rock zones respectively means: sampling within a preset width on both sides of the detection line of each of the representative rock zones.

[0023] Optionally, the conversion formula is: compressive strength = a * average penetration degree + b, where: a and b are constants.

[0024] Optionally, the step of using the conversion formula to calculate the compressive strength of the to-be-detected altered rock zone according to the average penetration degree of the to-be-detected altered rock zone includes the following steps:

[0025] Mark multiple penetration points on the to-be-detected altered rock zone;

[0026] Using the penetration nail to penetrate each of the penetration points with the same kinetic energy to obtain the penetration degree of each penetration point, and obtaining the average penetration degree of the to-be-detected altered rock zone according to the penetration degrees of all the penetration points of the to-be-detected altered rock zone;

[0027] Substituting the average penetration degree into the conversion formula to obtain the compressive strength of the to-be-detected altered rock zone.

[0028] Optionally, among the multiple penetration points of each to-be-detected altered rock zone, the distance between any two penetration points is 1.5 - 2 cm.

[0029] Optionally, the multiple penetration points of each to-be-detected altered rock zone are distributed in a horizontal straight line.

[0030] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0031] A method for detecting the strength of an altered rock zone provided by the present invention determines multiple to-be-detected altered rock zones, selects multiple representative rock zones from them, and uses the multiple representative rock zones to characterize all the to-be-detected altered rock zones; on this basis, by marking multiple to-be-detected points on each representative rock zone, using a penetration nail to penetrate each to-be-detected point to obtain the penetration degree, and sampling each representative rock zone to obtain the compressive strength of the sample, so as to obtain the compressive strength and average penetration degree of multiple representative rock zones, and make them correspond one by one; on this basis, through data fitting, a conversion formula between the compressive strength and the average penetration degree is obtained; on this basis, only by knowing the average penetration degree of the to-be-detected altered rock zone by using the method of penetrating the penetration nail, the compressive strength of this to-be-detected altered rock zone can be calculated by using the conversion formula, and once the conversion formula is determined, this conversion formula can be used to detect any to-be-detected altered rock zone later. Moreover, the method of penetrating the penetration nail can not only be carried out on-site, but also has simple operation, extremely high efficiency and extremely low cost, and can effectively solve the technical problems of the existing method for detecting the strength of an altered rock zone, such as complex process, long test period and high cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, form a part of this application, and do not limit the embodiments of the present invention. In the drawings:

[0033] Figure 1 It is a flowchart of the method for detecting the strength of an altered rock zone provided by the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0034] To make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the embodiments and the drawings. The illustrative embodiments and descriptions thereof of the present invention are only used to explain the present invention and do not limit the present invention.

[0035] First of all, it should be noted that during the research and experimentation process, the inventor learned that the penetration depths of altered rock zones with different strengths penetrated by penetration nails with the same kinetic energy show obvious regularity. The penetration degree of the altered rock zone with lower strength is larger, and the penetration degree of the altered rock zone with higher strength is smaller. Therefore, by only determining the specific relationship between the penetration degree and the compressive strength, the compressive strength can be characterized by the penetration degree.

[0036] It should be noted that the penetration nail refers to a nail-like object with a tip for penetration.

[0037] It should be noted that the penetration degree refers to the penetration depth of the penetration nail.

[0038] Please refer to Figure 1 , the embodiment of the present invention provides a method for detecting the strength of an altered rock zone, including the following steps:

[0039] S1. Determine multiple altered rock zones to be measured, and select multiple representative rock zones from all the altered rock zones to be measured;

[0040] S2. Mark multiple measurement points on each of the representative rock zones;

[0041] S3. Obtain penetration nails, use the penetration nails to penetrate each of the measurement points with the same kinetic energy, obtain the penetration degree of each of the measurement points, and according to the penetration degrees of all the measurement points of each of the representative rock zones, obtain the average penetration degree of each of the representative rock zones and summarize them to generate an average penetration degree statistical table;

[0042] S4. Take samples from each of the representative rock zones respectively to obtain multiple samples, conduct a load test on the samples to obtain the compressive strength of each of the samples, and combine the average penetration degree statistical table to generate an average penetration degree and compressive strength statistical table;

[0043] S5. According to the average penetration degree and compressive strength statistical table, fit the average penetration degree and the compressive strength to obtain a conversion formula;

[0044] S6. Use the conversion formula to calculate according to the average penetration degree of the altered rock zones to be measured to obtain the compressive strength of the altered rock zones to be measured.

[0045] The method for detecting the strength of altered rock zones provided by the present invention determines multiple altered rock zones to be measured, selects multiple representative rock zones therefrom, and uses the multiple representative rock zones to characterize all the altered rock zones to be measured; on this basis, by marking multiple measurement points on each representative rock zone, driving a penetration nail into each measurement point to obtain the penetration depth, and sampling each representative rock zone to obtain the compressive strength of the sample, thereby obtaining the compressive strengths and average penetration depths of multiple representative rock zones, and making them correspond one by one; on this basis, through data fitting, a conversion formula between the compressive strength and the average penetration depth is obtained; on this basis, only by knowing the average penetration depth of the altered rock zone to be measured by driving a penetration nail, the compressive strength of this altered rock zone to be measured can be calculated using the conversion formula, and once the conversion formula is determined, this conversion formula can be used to detect any altered rock zone to be measured later. Moreover, the method of driving a penetration nail can not only be carried out on-site, but also has simple operation, extremely high efficiency, and extremely low cost, and can effectively solve the technical problems of the existing method for detecting the strength of altered rock zones, such as complex process, long test period, and high cost.

[0046] Further, the selection of multiple representative rock zones from all the altered rock zones to be measured includes the following steps:

[0047] S1.1. Conduct a geological survey on all the altered rock zones to be measured, and classify all the altered rock zones to be measured according to geological conditions;

[0048] S1.2. Select one of the altered rock zones to be measured in each category as a representative rock zone.

[0049] Specifically, the geological conditions include any one or a combination of multiple of development scale, genetic mechanism, and mechanical properties.

[0050] Further, the marking of multiple measurement points on each representative rock zone includes the following steps:

[0051] S2.1. Level each representative rock zone according to the plumb plane;

[0052] S2.2. Draw a detection line on each representative rock zone in the horizontal direction, so that both ends of the detection line intersect with the boundaries of the corresponding representative rock zone, forming two intersection points;

[0053] S2.3. Take any one of the two intersection points as the starting point, and mark multiple measurement points along the detection line at a preset interval.

[0054] It should be noted that when driving the penetration nail, make the penetration nail perpendicular to the leveled plane.

[0055] Specifically, the marking method uses the method of spray painting the points to be measured, and marks the test numbers near the representative rock belts.

[0056] Specifically, the preset spacing is 1.5 - 2 cm.

[0057] It should be noted that any device in the prior art can be used to energize the penetration nail. For example, any existing energizing device that stores elastic potential energy through a spring and then converts the elastic potential energy into kinetic energy can be used. For example, any existing magnetic energizing device can be used. For example, any existing hammer with a fixed striking force can be used to vertically strike the tail end of the penetration nail, etc. As long as the penetration nail can be given a fixed kinetic energy to make it move axially.

[0058] It should be noted that scale lines can be axially arranged on the penetration nail to determine the penetration degree; or any measuring tool in the prior art can be used to measure the length of the part of the penetration nail outside the soft rock belt to be measured, and the penetration degree can be obtained by reverse deduction.

[0059] Further, the sampling from each of the representative rock belts means: sampling within the preset width on both sides of the detection line of each of the representative rock belts.

[0060] Specifically, the preset width is one - fourth to one - third of the longitudinal width of the representative rock belt.

[0061] It should be noted that the average penetration degree and the compressive strength are generally fitted using existing software such as matlab.

[0062] Further, the conversion formula is: compressive strength = a * average penetration degree + b, where: a and b are constants.

[0063] It should be noted that the unit of compressive strength is generally selected as MPa, and the unit of average penetration degree is generally selected as mm.

[0064] It should be noted that in other embodiments, a more accurate formula model can also be used, such as a curve model. In conventional engineering, a linear model can handle the vast majority of cases.

[0065] Further, the calculation of the compressive strength of the altered rock belt to be measured according to the average penetration degree of the altered rock belt to be measured using the conversion formula includes the following steps:

[0066] S6.1. Mark multiple penetration points on the altered rock belt to be measured;

[0067] S6.2. Use the penetration nail to penetrate each of the penetration points with the same kinetic energy to obtain the penetration depth of each penetration point, and obtain the average penetration depth of the to-be-detected altered rock zone according to the penetration depths of all the penetration points of the to-be-detected altered rock zone.

[0068] S6.3. Substitute the average penetration depth into the conversion formula to obtain the compressive strength of the to-be-detected altered rock zone.

[0069] Preferably, among the multiple penetration points of each to-be-detected altered rock zone, the distance between any two penetration points is 1.5 - 2 cm.

[0070] Preferably, the multiple penetration points of each to-be-detected altered rock zone are distributed in a horizontal straight line.

[0071] Embodiment

[0072] This embodiment provides a method for detecting the strength of an altered rock zone, including the following steps:

[0073] A. Determine multiple to-be-detected altered rock zones, and select multiple representative rock zones from all the to-be-detected altered rock zones.

[0074] Specifically, conduct a geological survey on all the to-be-detected altered rock zones, classify all the to-be-detected altered rock zones according to geological conditions, and select one to-be-detected altered rock zone from each category as a representative rock zone.

[0075] B. Mark multiple to-be-detected points on each representative rock zone.

[0076] Specifically, level each representative rock zone according to the plumb plane, draw a detection line on each representative rock zone in the horizontal direction, make both ends of the detection line intersect with the boundaries of the corresponding representative rock zone to form two intersection points, take the left intersection point as the starting point, and mark multiple to-be-detected points along the detection line at intervals of 1.5 - 2 cm.

[0077] C. Select a type of penetration nail, use the penetration nail to penetrate each to-be-detected point with the same kinetic energy to obtain the penetration depth of each to-be-detected point, obtain the average penetration depth of each representative rock zone according to the penetration depths of all the to-be-detected points of each representative rock zone, summarize them, and generate an average penetration depth statistical table, as shown in Table 1.

[0078] Table 1 Average Penetration Depth Statistical Table

[0079]

[0080]

[0081] D. Samples are taken from each representative rock zone respectively to obtain multiple samples. The load tests are carried out on the samples to obtain the compressive strength of each sample. Combining with the average penetration degree statistical table (Table 1), an average penetration degree and compressive strength statistical table is generated, as shown in Table 2.

[0082] Table 2 Average Penetration Degree and Compressive Strength Statistical Table

[0083] Representative rock zone Average penetration depth (mm) Compressive strength (Mpa) sbyd1 35 10 sbyd2 30 15 sbyd3 12 30 sbyd4 22 23 sbyd5 6 40 sbyd6 25 20 … … …

[0084] E. According to the average penetration degree and compressive strength statistical table, the average penetration degree and compressive strength are fitted to obtain a conversion formula. The conversion formula is: Compressive strength = a * average penetration degree + b, where a and b are constants.

[0085] F. Using the conversion formula, the compressive strength of the to-be-detected altered rock zone is calculated according to the average penetration degree of the to-be-detected altered rock zone.

[0086] Specifically, multiple penetration points are marked on the to-be-detected altered rock zone. The penetration nails are used to penetrate each penetration point with the same kinetic energy to obtain the penetration degree of each penetration point. According to the penetration degrees of all the penetration points of the to-be-detected altered rock zone, the average penetration degree of the to-be-detected altered rock zone is obtained. The average penetration degree is substituted into the conversion formula to obtain the compressive strength of the to-be-detected altered rock zone.

[0087] The specific embodiments described above further elaborate on the purpose, technical solutions, and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not used to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for detecting the strength of an altered rock zone, characterized in that It includes the following steps: Determine multiple alteration rock zones to be measured, and select multiple representative rock zones from all the alteration rock zones to be measured; Mark multiple measurement points on each of the representative rock zones; Obtain penetration nails, use the penetration nails to penetrate each of the measurement points with the same kinetic energy, obtain the penetration depth of each of the measurement points, and based on the penetration depths of all the measurement points of each representative rock zone, obtain the average penetration depth of each representative rock zone and summarize them to generate an average penetration depth statistical table; Take samples from each of the representative rock zones respectively to obtain multiple samples, conduct load tests on the samples to obtain the compressive strength of each sample, and combine with the average penetration depth statistical table to generate an average penetration depth and compressive strength statistical table; According to the average penetration depth and compressive strength statistical table, fit the average penetration depth and the compressive strength to obtain a conversion formula; Use the conversion formula to calculate based on the average penetration depth of the alteration rock zones to be measured to obtain the compressive strength of the alteration rock zones to be measured; The step of selecting multiple representative rock zones from all the alteration rock zones to be measured includes the following steps: Conduct geological surveys on all the alteration rock zones to be measured, and classify all the alteration rock zones to be measured according to geological conditions; Select one of the alteration rock zones to be measured from each category as a representative rock zone; The geological conditions include any one or a combination of multiple of development scale, genetic mechanism, and mechanical properties; The step of marking multiple measurement points on each of the representative rock zones includes the following steps: Level each of the representative rock zones along the plumb plane; Draw a detection line on each of the representative rock zones in the horizontal direction, so that the two ends of the detection line intersect with the boundaries of the corresponding representative rock zones respectively to form two intersection points; Take any one of the two intersection points as the starting point, and mark multiple measurement points along the detection line at a preset interval; The conversion formula is: Compressive strength = a * Average penetration depth + b, where: a and b are constants.

2. The altered rock zone strength detection method according to claim 1, wherein The preset interval is 1.5 - 2 cm.

3. The method for detecting the strength of the altered rock zone according to claim 1, characterized in that, The step of taking samples from each of the representative rock zones respectively means: taking samples within a preset width on both sides of the detection line of each representative rock zone.

4. The method for detecting the strength of the altered rock zone according to claim 1, wherein, The step of using the conversion formula to calculate based on the average penetration depth of the alteration rock zones to be measured to obtain the compressive strength of the alteration rock zones to be measured includes the following steps: Mark multiple penetration points on the alteration rock zones to be measured; Use the penetration nails to penetrate each of the penetration points with the same kinetic energy, obtain the penetration depth of each of the penetration points, and based on the penetration depths of all the penetration points of the alteration rock zones to be measured, obtain the average penetration depth of the alteration rock zones to be measured; Substitute the average penetration depth into the conversion formula to obtain the compressive strength of the alteration rock zones to be measured.

5. The method for detecting the strength of the altered rock zone according to claim 4, wherein, Among the multiple penetration points of each alteration rock zone to be measured, the distance between any two penetration points is 1.5 - 2 cm.

6. The method for detecting the strength of the altered rock zone according to claim 4, wherein The multiple penetration points of each alteration rock zone to be measured are distributed along a horizontal straight line.

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