Soft rock fissure zone development detection device and use method thereof

Abstract

The invention discloses a soft rock fissure zone development detection device and a use method thereof, and relates to the technical field of soft rock environment coal mining fissure zone development law detection, the soft rock fissure zone development detection device comprises a probe, a gradient resistivity detection device, a short spacing density logging instrument, a logging instrument connector, a potential resistivity detection device, a logging instrument connecting block, a coupler, a wire harness and a visual detection system; a visual detection system is arranged on the coupler, the visual detection system is composed of a video probe and a limiting groove, and after short-spacing density logging is finished, downward probing of the video probe is achieved through control of the coupler, so that visual detection of drilling surrounding rock is achieved, and fractured zone evolution law analysis is conducted in combination with short-spacing density logging data. When fractured zone detection is carried out in the soft rock environment, the problem of abnormal fractured zone evolution caused by uneven rock stratum thickness distribution can be effectively solved, and the device is high in applicability, simple in structure, reasonable in design, high in operability and easy to master by engineering technicians of coal mine enterprises.

Description

Technical Field

[0001] This invention relates to the field of coal mining technology, specifically to the field and method of detecting the development of soft rock fracture zones. Background Technology

[0002] The development height of the fracture zone in the roof of the working face is a key consideration in the management of mining pressure, control of surface coal mining subsidence areas, and management of aquifers and surface water. It is affected by the geological structure of the overlying strata, mining activities, and the physical and mechanical properties of the rock mass. The lower the strength of the strata and the greater the thickness of the coal seam being mined, the higher the development height of the fracture zone, the more complex the fracture field, the larger the area of ​​the coal mining subsidence area, the more water channels, and the higher the degree of danger.

[0003] Currently, commonly used methods for measuring water-conducting fracture zones include drilling straight holes on the surface to observe mud consumption and conduct borehole inspection, or drilling overhead holes in the well to conduct water pressure tests. The exploration of the floor failure zone mainly relies on drilling downholes to conduct water pressure tests and borehole inspection. These methods require drilling multiple holes, resulting in a large workload, high cost, low detection accuracy, and a lack of guidance for production.

[0004] Existing detection devices have the following drawbacks: 1. They are limited to conventional methods such as water pressure testing and borehole inspection, which lack detailed detection of the distribution of lithology in the overlying strata; 2. Due to the special laws governing the evolution of fracture zones in soft rock environments, such as mudstone, traditional detection devices have not fully considered the characteristics of soft rock, such as low strength and easy borehole collapse. At the same time, soft rock fracture zones have a certain degree of healing, resulting in inaccurate detection results. Summary of the Invention

[0005] To address the shortcomings of existing soft rock fracture zone detection devices, this invention provides a soft rock fracture zone development detection device and its usage method. By combining short-source-distance density logging with borehole inspection, it achieves accurate determination of overburden lithology and provides a scientific basis for borehole inspection analysis, thus ensuring the accuracy of fracture zone evolution in soft rock environments.

[0006] To achieve the above objectives, the technical solution of the present invention is as follows:

[0007] A soft rock fracture zone development detection device includes a probe, a gradient resistivity detection device, a short source distance density logging tool, a logging tool connector, a potential resistivity detection device, a logging tool connector block, a coupler, a wiring harness, and a visualization detection system.

[0008] The coupler is equipped with a visual detection system, and the wire harness and short-pitch density logging tool are connected through the coupler via a grooved connector.

[0009] The visualization detection system consists of a video probe and a limiting groove, and the probe is controlled by a wiring harness;

[0010] The short-source-distance density logging tool type is preferred, but different logging tool types can be selected according to the needs of the site during actual operation.

[0011] The short source distance density logging tool consists of a probe, a gradient resistivity detection device, a logging tool connector, a potential resistivity detection device, and a logging tool connector block.

[0012] The probe is preferably made of steel to cope with potential damage to the short-spacing density logging tool caused by borehole irregularities;

[0013] The above-mentioned device for detecting the development of soft rock fracture zones and its method of use include the following steps:

[0014] Step 1: Based on the borehole columnar section of the mining area, roughly determine the strata to which the key strata belong using the theory of key overlying strata. When the lithology of the overlying strata is relatively simple, it can be determined directly. Based on the movement law of the overlying strata and with the help of the theory of coal mining subsidence, roughly delineate the boundary of the coal mining subsidence area, preliminarily determine the location of the surface boreholes, and calculate the height of the fracture zone;

[0015] Step 2: Drill vertically downwards at the surface drilling location determined in Step 1. The drilling diameter should be 10cm. Enlarge the hole. Due to the low strength of the overlying rock layer, the drilling should be completed within 24 hours to avoid hole collapse due to low strength. When the drilling reaches near the theoretical value, release the visualization detection system through the wire harness control and use the video probe to detect the surrounding rock fissures.

[0016] Step 3: After drilling to near the theoretical value, conduct a video inspection of the surrounding rock every 5m of drilling until the results of two consecutive fracture development inspections are continuous, the fracture development is obvious, the fracture rate is high, and the width and area of ​​the fracture increase as you go down. Then you can determine that you have entered the fracture zone height range.

[0017] Step 4: Install a short-spacing density logging tool and perform short-spacing density logging from the surface downwards. Analyze the logging results using the gamma-ray principle. After determining the lithology, combine the video information collected by the visualization detection device to analyze the evolution law of soft rock fracture zones.

[0018] I. This invention, through the combination of short-spacing density logging and a visualization detection system, can effectively address the unique changes in the evolution of fracture zones in downhole mining under soft rock environments, thereby improving the accuracy of fracture zone detection;

[0019] Second, this invention connects the short-spacing density logging instrument with the grooved connector of the coupler, which can effectively realize independent operation of visual detection and short-spacing density logging, simplifying the workflow and improving work efficiency. At the same time, its applicability can be enhanced by changing the density logging instrument for different overburden conditions. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overlying rock and key layers in a soft rock environment provided by the present invention;

[0021] Figure 2 This invention provides a diagram showing the distribution of different fracture zones and the location of measuring points in a soft rock environment.

[0022] Figure 3 This is a schematic diagram of the soft rock fracture zone development detection device provided by the present invention;

[0023] Wherein: 1-Probe; 2-Gradient resistivity detection device; 3-Short source distance density logging tool; 4-Logging tool connector; 5-Potential resistivity detection device; 6-Logging tool connector block; 7-Coupler; 8-Wire harness; 9-Visual detection system. Detailed Implementation

[0024] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. 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 should fall within the scope of protection of the present invention.

[0025] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0026] In order to solve the problems existing in the current technology, such as Figures 1 to 3As shown, the present invention provides a soft rock fracture zone development detection device, including a probe (1), a gradient resistivity detection device (2), a short source distance density logging instrument (3), a logging instrument connector (4), a potential resistivity detection device (5), a logging instrument connector block (6), a coupler (7), a wiring harness (8), and a visualization detection system (9).

[0027] A visualization detection system (9) is installed on the coupler (7), and the wire harness (8) and the short source distance density logging instrument (3) are connected by a grooved connector through the coupler (7).

[0028] The visual detection system (9) consists of a video probe and a limiting groove, and the probe is controlled by a wire harness (8).

[0029] The short-source-distance density logging tool (3) is the preferred type. In actual operation, different logging tool types can be selected according to the needs of the site.

[0030] The short-source-distance density logging tool (3) consists of a probe (1), a gradient resistivity detection device (2), a logging tool connector (4), a potential resistivity detection device (5), and a logging tool connector (6).

[0031] The probe (1) is preferably made of steel to cope with potential damage to the short source distance density logging instrument (3) caused by borehole irregularities.

[0032] The above-mentioned device for detecting the development of soft rock fracture zones and its method of use include the following steps:

[0033] Step 1: Based on the borehole columnar section of the mining area, roughly determine the strata to which the key strata belong using the theory of key overlying strata. When the lithology of the overlying strata is relatively simple, it can be determined directly. Based on the movement law of the overlying strata and with the help of the theory of coal mining subsidence, roughly delineate the boundary of the coal mining subsidence area, preliminarily determine the location of the surface boreholes, and calculate the height of the fracture zone;

[0034] Step 2: Drill vertically downwards at the surface drilling location determined in Step 1. The drilling diameter should be 10cm. Expand the hole. Due to the low strength of the overlying rock layer, the drilling should be completed within 24 hours to avoid hole collapse due to low strength. When the drilling reaches the theoretical value, release the visualization detection system (9) through the wire harness (8) and use the video probe to detect the surrounding rock fissures.

[0035] Step 3: After drilling to near the theoretical value, conduct a video inspection of the surrounding rock every 5m of drilling until the results of two consecutive fracture development inspections are continuous, the fracture development is obvious, the fracture rate is high, and the width and area of ​​the fracture increase as you go down. Then you can determine that you have entered the fracture zone height range.

[0036] Step 4: Install the short source distance density logging tool (3) and perform short source distance density logging from the surface downwards. Analyze the logging results using the gamma ray principle. After determining the lithology, combine the video information collected by the visualization detection system (9) to analyze the evolution law of soft rock fracture zones.

Claims

1. A device for detecting the development of fracture zones in soft rock, characterized in that, The system includes a probe (1), a gradient resistivity detection device (2), a short-spacing density logging instrument (3), a logging instrument connector (4), a potential resistivity detection device (5), a logging instrument connector (6), a coupler (7), a wiring harness (8), and a visualization detection system (9). The coupler (7) is equipped with a visualization detection system (9), which consists of a video probe and a limiting groove. The short-spacing density logging instrument is connected to the visualization detection system (9) and the wiring harness (8) through the coupler (7). After the short-spacing density logging is completed, the wiring harness (8) controls the visualization detection system (9) to lower the video probe, thereby realizing the visualization detection of the surrounding rock fractures.

2. The soft rock fracture zone development detection device according to claim 1, characterized in that: The coupler (7) is equipped with a visualization detection system (9), and the wire harness (8) and the short source distance density logging instrument (3) are connected by a grooved connector through the coupler (7).

3. The soft rock fracture zone development detection device according to claim 1, characterized in that: The visualization detection system (9) consists of a video probe and a limiting groove, and the probe (1) is controlled by a wire harness (8).

4. The soft rock fracture zone development detection device according to claim 1, characterized in that: The short-source-distance density logging tool (3) is the preferred type. In actual operation, different logging tool types can be selected according to the needs of the site.

5. The soft rock fracture zone development detection device according to claim 1, characterized in that: The short source distance density logging tool (3) consists of a probe (1), a gradient resistivity detection device (2), a logging tool connector (4), a potential resistivity detection device (5), and a logging tool connector (6).

6. The soft rock fracture zone development detection device according to claim 1, characterized in that: The probe (1) is preferably a steel probe to cope with potential damage to the short-spacing density logging instrument (3) caused by borehole irregularities.

7. A method for using a soft rock fracture zone development detection device, characterized in that: Includes the following steps: Step 1: Based on the borehole columnar section of the mining area, roughly determine the strata to which the key strata belong using the theory of key overlying strata. When the lithology of the overlying strata is relatively simple, it can be determined directly. Based on the overburden movement pattern and with the help of the coal mining subsidence theory, the boundary of the coal mining subsidence area was roughly delineated, the location of surface boreholes was preliminarily determined, and the theoretical value of the fracture zone height was calculated. Step 2: Drill vertically downwards at the surface drilling location determined in Step 1. The drilling diameter should be 10cm. Expand the hole. Due to the low strength of the overlying rock layer, the drilling should be completed within 24 hours to avoid hole collapse due to low strength. When the drilling reaches the theoretical value, release the visualization detection system (9) through the wire harness (8) and use the video probe to detect the surrounding rock fissures. Step 3: After drilling to near the theoretical value, conduct a video inspection of the surrounding rock every 5m of drilling until the results of two consecutive fracture development inspections are continuous, the fracture development is obvious, the fracture rate is high, and the width and area of ​​the fracture increase as you go down. Then you can determine that you have entered the fracture zone height range. Step 4: Install the short source distance density logging tool (3) and perform short source distance density logging from the surface downwards. Analyze the logging results using the gamma ray principle. After determining the lithology, combine the video information collected by the visualization detection system (9) to analyze the evolution law of soft rock fracture zones.

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