Advanced geology forecasting method for underground water-sealed cave depot

Abstract

The invention provides an advanced geological forecasting method for an underground water-sealed cave depot, which relates to the technical field of geological forecasting, and comprises the following steps: S1, drilling a water curtain hole, synchronously recording the drilling condition of the water curtain hole, and completing the drilling of the required water curtain hole before the excavation of a main cavern; s2, after water curtain hole drilling is finished, imaging testing is carried out, a full-hole wall high-definition rock mass picture is shot, and a video is recorded; s3, water curtain hole drilling records and imaging results are comprehensively analyzed, various abnormal geologies are interpreted in a classified mode, and the interpreted abnormal geologies are drawn on a plane graph; s4, according to the geological information disclosed by the water curtain holes, the geological conditions of the main cavern in the underground water-sealed cave depot are speculated; by fully utilizing the geological information disclosed by the water curtain holes, the method can be suitable for predicting the geology of the water-sealed cave depot, and has guidance for predicting the geology of the water-sealed cave depot.

Description

Technical Field

[0001] The invention relates to the technical field of geological prediction, and in particular to an advanced geological prediction method for underground water-sealed caverns. Background Art

[0002] Underground water-sealed caverns are underground spaces built in rock mass for storing crude oil, liquefied petroleum gas and other media. The underground structure is mainly composed of construction tunnels, water curtain tunnels, main caverns and water curtain holes.

[0003] Before excavation and construction of underground projects, it is necessary to carry out advanced geological forecasting work to predict and analyze the engineering geology and hydrogeology conditions in front of the planned cavern in advance, so as to facilitate the design of excavation, grouting and water blocking, and support schemes in advance. At present, the advanced geological forecasting work of underground water-sealed cavern projects mainly refers to the relevant advanced geological forecasting methods of highways, railways or water conservancy and hydropower systems, and predicts the geological conditions of the main cavern during the excavation process of underground water-sealed caverns.

[0004] However, since the geological conditions, construction technology and focus of underground water-sealed cavern projects are different from those of underground projects such as highway and railway tunnels, the use of the above-mentioned advanced geological prediction method has the problem of poor guidance and applicability. Summary of the invention

[0005] 1. Technical issues to be resolved

[0006] In view of the deficiencies in the prior art, the present invention provides an advanced geological prediction method for underground water-sealed caverns, which solves the problems caused by the use of the above-mentioned advanced geological prediction method in the prior art.

[0007] (II) Technical solution

[0008] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0009] In the present invention, a method for advanced geological prediction of underground water-sealed caverns comprises the following steps:

[0010] S1: Drill the water curtain holes and record the drilling status of the water curtain holes simultaneously. Complete the drilling of the required water curtain holes before excavating the main cavern.

[0011] S2: After the water curtain hole drilling is completed, an imaging test is carried out to take high-definition rock photos of the entire hole wall and record a video;

[0012] S3: Comprehensive analysis of water curtain hole drilling records and imaging results, classification and interpretation of various abnormal geology, and drawing on the plane map;

[0013] S4: Based on the geological information revealed by the water curtain hole, the geological conditions of the main cavern in the underground water-sealed cavern are inferred;

[0014] S5: Based on the results of extended speculation and combined with other geological data, a long-distance advanced geological forecast report for the main cavern is compiled, giving the pile number, affected width, structural occurrence, lithology and surrounding rock grade of each geological structure development position of the tunnel section to be predicted;

[0015] Propose construction measures based on the identified geological conditions and provide guidance on the excavation of the main cavern;

[0016] Furthermore, during drilling, the azimuth of the water curtain hole is consistent with the axial direction of the main cavern, and the depth of the water curtain hole covers the entire length of the main cavern, thus realizing long-distance geological prediction of the main cavern of the water-sealed cavern.

[0017] Furthermore, the imaging video is observed and analyzed segment by segment to find the location where the water output changes in the water curtain holes and record the depth of the change;

[0018] By comparing and analyzing the recorded change depth with other data, we can obtain the joint development conditions and rock fragmentation of the cave wall at the location where the water volume changes.

[0019] Furthermore, the development of the hole wall joints was analyzed based on the imaging results, and rose diagrams of the joint direction and dip were drawn to analyze the lithology changes and fragmentation of the hole wall rock mass and the development direction of the dominant joints.

[0020] Furthermore, the geological structures, rock type changes, seepage joints, etc. found in the water curtain holes are extended to the main cavern according to their occurrence, and their development positions and scales in the main cavern are speculated, and the engineering geology and hydrogeology conditions of the main cavern are analyzed and speculated.

[0021] Furthermore, the trigonometric method is used to extend the inference to the main cavern.

[0022] (III) Beneficial effects

[0023] The present invention provides a method for advanced geological prediction of underground water-sealed caverns. Compared with the prior art, it has the following beneficial effects:

[0024] By making full use of the geological information revealed by the water curtain holes, it can be applied to the prediction of water-sealed cavern geology and provide guidance for the prediction of water-sealed cavern geology. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. 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 paying creative work.

[0026] Figure 1 This is a schematic diagram of the underground structure distribution of the underground water-sealed cavern;

[0027] Figure 2 This is a schematic diagram of the relationship between the main cavern, water curtain tunnel and water curtain hole;

[0028] Figure 3 for Figure 2 Bottom view of

[0029] Figure 4 This is a diagram of the geological structure in the underground water-sealed cavern and the distribution status of unfavorable geology in the water curtain and main cavern layer. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] The embodiment of the present application provides a method for advanced geological prediction of underground water-sealed caverns, which solves the problem that the prediction method is not very instructive and applicable by predicting the interior geology of the main cavern in the underground water-sealed cavern, and achieves the purpose of long-distance hydrogeological and engineering geological prediction of the main cavern of the underground water-sealed cavern.

[0032] The technical solution in the embodiment of the present application is to solve the above technical problems, and the overall idea is as follows:

[0033] The construction location of the water-sealed cavern is specially selected after preliminary investigation and demonstration. It is generally built in crystalline rock with good rock conditions and relatively small water seepage. Under this large geological condition background, the surrounding rock conditions generally tend to gradually improve from top to bottom. Since the main cavern is located 26 to 31 meters (generally 26 meters) below the water curtain hole, it is close to the water curtain hole and located below it. Therefore, the geological information revealed by the water curtain hole can reflect and represent the geological conditions of the main cavern;

[0034] At present, according to a large amount of practical experience, the geological conditions of the main cavern are basically consistent with those revealed by the water curtain holes at the corresponding locations, and the local geological conditions are even better than those of the water curtain holes.

[0035] Therefore, if Figure 1-Figure 4 As shown, the research found that by making full use of the geological information revealed by the water curtain holes, it can be applied to the prediction of water-sealed cavern geology and has guiding significance for the prediction of water-sealed cavern geology.

[0036] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0037] like Figure 1-Figure 4 As shown, a method for advanced geological prediction of underground water-sealed caverns comprises the following steps:

[0038] S1: Drill the water curtain holes and record the drilling status of the water curtain holes simultaneously. Complete the drilling of the required water curtain holes before excavating the main cavern.

[0039] S11: During drilling, the azimuth of the water curtain hole is consistent with the axis direction of the main cavern, and the depth of the water curtain hole covers the entire length of the main cavern, realizing the long-distance geological prediction of the main cavern of the water-sealed cavern;

[0040] When performing step S1, it should be noted that there are water curtain holes directly above all main caverns, the azimuth of the water curtain holes is consistent with the axis direction of the main cavern (i.e., parallel to the main cavern), and covers the entire length of the main cavern;

[0041] The spacing between water curtain holes is generally 10 meters, and the distance from the main cavern roof is generally 26 to 31 meters. The water curtain holes have been drilled and tested in the hole before the main cavern is excavated, and water supply has been normal. Figure 2-Figure 3 As shown;

[0042] The width of the main cave is generally 20 to 24 meters. When the spacing between the water curtain holes is 10 meters, there are generally 3 to 4 water curtain holes distributed directly above the width of the main cave;

[0043] When recording the drilling conditions of the water curtain hole, the main records include the depth, location and details of drilling sticking, breakthrough, color of drilling circulating water, hole collapse, changes in water output, etc.

[0044] S2: After the water curtain hole drilling is completed, an imaging test is carried out to take high-definition rock photos of the entire hole wall and record a video;

[0045] S3: Comprehensive analysis of water curtain hole drilling records and imaging results, classification and interpretation of various abnormal geology, and drawing on the plane map;

[0046] When conducting a comprehensive analysis of the geological information revealed by the water curtain hole, a comprehensive analysis is conducted on the drill sticking, advance, drilling circulating water color, hole collapse, water output changes, etc. based on the water curtain hole drilling records and the existing survey results. Figure 4 shown.

[0047] S31: observe and analyze the imaging video segment by segment, find the position where the water flow in the water curtain hole changes, and record the change depth;

[0048] By comparing and analyzing the recorded change depth with other data, we can obtain the joint development conditions and rock fragmentation of the cave wall at the location where the water volume changes.

[0049] S32: Analyze the development of hole wall joints based on the imaging results, draw joint strike and dip rosettes, analyze the lithology changes and fragmentation of the hole wall rock mass, and the development direction of the dominant joints;

[0050] Among them, the joint development conditions include the number of joints, occurrence, opening or filling of joint surfaces, etc.

[0051] In summary, through step S3, according to the comparison between the drilling construction records, the in-hole imaging records and the preliminary analysis results, a comprehensive analysis is conducted in combination with the previous survey data, the actual geological conditions revealed by the water curtain tunnel excavation, etc., to find out the location, scale and occurrence of the geological structures (faults, fracture zones, dyke development zones, alteration zones, joint dense development zones, etc.) revealed in the water curtain hole, find out the location and length of different lithologies and their changes, find out the location of the seepage section and analyze the amount of seepage, the development and occurrence of seepage joints and other information.

[0052] It should be noted that the control of groundwater in the construction of underground water-sealed caverns is mainly based on water stopping and plugging. First, it is necessary to ensure that groundwater does not lose or reduce the loss to ensure that the groundwater level remains within the design allowable value. Second, it is necessary to ensure that the amount of seepage in the underground space (main cavern) formed by excavation does not exceed the provisions of the design and specification standards. Therefore, it is different from other underground projects to identify, analyze and predict the location, scale, characteristics and other conditions of groundwater seepage, so as to facilitate the formulation of targeted grouting and plugging measures to control groundwater leakage. When this method is used for long-distance advanced geological prediction of the main cavern, the distribution location and seepage conditions of the seepage tunnel section in front of the main cavern can be predicted, which improves the geological prediction effect.

[0053] S4: Based on the geological information revealed by the water curtain hole, the geological conditions of the main cavern in the underground water-sealed cavern are inferred;

[0054] S41: The geological structures, lithology changes, seepage joints, etc. found in the water curtain holes are extended to the main cavern according to their occurrence using the trigonometric function method to infer their development position and scale in the main cavern, and the engineering geology and hydrogeology conditions of the main cavern are analyzed and inferred;

[0055] When the trigonometric method is used to extend toward the main cavern, it generally extends downward 26 to 31 meters;

[0056] S5: Based on the results of extended speculation and combined with other geological data, a long-distance advanced geological forecast report for the main cavern is compiled, giving the pile number, affected width, structural occurrence, lithology and surrounding rock grade of each geological structure development position of the tunnel section to be predicted;

[0057] Propose construction measures based on the identified geological conditions and provide guidance on the excavation of the main cavern;

[0058] In the prior art, the advanced geological prediction work is mainly implemented with reference to the relevant advanced geological prediction standards for highways, railways or water conservancy and hydropower systems. Highway and railway tunnels are planned according to the route selection. After the route is determined, measures must be taken to cross or span regardless of the geological conditions. Its function is to meet the needs of traffic passage, and route adjustment is generally not allowed. However, the underground water-sealed cavern project is to build an underground storage space;

[0059] When the local geological conditions are poor, which may cause great construction difficulties, high quality or safety risks, long construction period, and high cost investment, etc., it is possible to consider adjusting the plane position or structural layout of the underground project to overcome the above influences, as long as the design requirements of the cave storage capacity are met;

[0060] Therefore, when it is discovered in advance that the planned cavern has a large adverse geological impact, the optimal crossing plan can be studied in advance. When the cost is too high, an avoidance plan may be chosen. Therefore, the results of the advanced geological forecast of underground water-sealed caverns are not only an advance prediction of geological conditions and a prediction and control of geological risks, but also play a role in supporting decision-making whether to continue excavation or take avoidance measures.

[0061] Because the geological conditions, construction technology and focus of underground water-sealed caverns are different from those of underground projects such as highways and railway tunnels, the advanced prediction methods used are also different and focused, so the reference standards are not very instructive and applicable to the advanced geological prediction of underground water-sealed caverns.

[0062] At present, geological analysis, geophysical exploration, and advance drilling are used to conduct advance geological forecasts before the excavation of tunnels and caverns in underground water-sealed caverns. The development of geological structures such as faults and fracture zones within a certain distance in front of the face, rock integrity, rock properties and weathering degree, rock water content, and surrounding rock grade and other engineering geological and hydrogeological conditions are predicted to provide a basis for excavation design and construction.

[0063] Among them, the geological analysis method is a method of analyzing and speculating the geological conditions of the tunnel section to be predicted based on the existing geological survey results and the actual geological conditions revealed by the excavated tunnel section. The geophysical method is to use seismic wave method or electrical method, electromagnetic method to conduct excitation sampling on the tunnel face or side wall, and interpret, analyze and speculate the geological conditions of the tunnel section to be predicted based on the physical property differences of the rock mass in front of the tunnel face.

[0064] At present, geological analysis method, geophysical prospecting method, or a combination of the two methods are often used to predict the geology of underground water-sealed caverns. However, when analyzing the actual surrounding rock conditions revealed by the excavated tunnel section, since the main cavern is excavated forward, the actual surrounding rock conditions of the excavated tunnel section behind cannot represent the geological conditions of the unexcavated section in front. At the same time, although the water curtain roadway above the main cavern has been excavated, the water curtain roadway and the main cavern are vertically intersected, and the distribution of the water curtain roadway does not fully cover the main cavern. Therefore, the geological conditions revealed by the upper water curtain roadway are also limited in the analysis and speculation of the geological conditions of the main cavern, and cannot provide better guidance;

[0065] The study found that the caverns being excavated were selected after multiple site selection and demonstration, and their geological conditions were often good.

[0066] By making full use of the geological information revealed by the water curtain holes, it can be applied to the prediction of the geology of water-sealed caverns and has guiding significance for the prediction of the geology of water-sealed caverns.

[0067] In summary, compared with the prior art, the present invention has the following beneficial effects:

[0068] 1. The present invention adds a long-distance geological prediction method for the main chamber of a water-sealed cavern, enriching and improving the current advanced geological prediction method for underground water-sealed caverns;

[0069] 2. The present invention does not add special instruments and equipment. The in-hole television imaging equipment used is a relatively conventional exploration equipment. The equipment cost, technical difficulty of operation, and human resource investment have not increased substantially;

[0070] 3. When predicting the long-distance geology of the main cavern, this method solves the problems of the traditional geophysical method, which requires other construction processes and time for water-sealed caverns, and the uncertainty of geological conditions caused by the multi-solution of geophysical results. It also solves the singleness of the analysis materials when using the geological analysis method.

[0071] 4. The method of the present invention can not only detect the unfavorable geological bodies with great influence such as the developed geological structure of the main cave in advance, but also predict the location and seepage situation of the seepage tunnel section of the main cave in advance, which is impossible for traditional long-distance geological prediction;

[0072] 5. By adopting the method of the present invention, the accuracy of advanced geological prediction is improved.

[0073] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0074] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for advanced geological prediction of underground water-sealed caverns, characterized in that: The following steps are involved: S1: Drill the water curtain holes and record the drilling status of the water curtain holes simultaneously. Complete the drilling of the required water curtain holes before excavating the main cavern. S2: After the water curtain hole drilling is completed, an imaging test is carried out to take high-definition rock photos of the entire hole wall and record a video; S3: Comprehensive analysis of water curtain hole drilling records and imaging results, classification and interpretation of various abnormal geology, and drawing on the plane map; S4: Based on the geological information revealed by the water curtain hole, the geological conditions of the main cavern in the underground water-sealed cavern are inferred; S5: Based on the results of extended speculation and combined with other geological data, a long-distance advanced geological forecast report for the main cavern is compiled, giving the pile number, affected width, structural occurrence, lithology and surrounding rock grade of each geological structure development position of the tunnel section to be predicted; Based on the identified geological conditions, construction measures are proposed and excavation guidance is provided for the main cavern.

2. The method for advanced geological prediction of underground water-sealed caverns according to claim 1, characterized in that: During drilling, the azimuth of the water curtain hole is consistent with the axial direction of the main cavern, and the depth of the water curtain hole covers the entire length of the main cavern, realizing long-distance geological prediction of the main cavern of the water-sealed cavern.

3. The method for advanced geological prediction of underground water-sealed caverns according to claim 1, characterized in that: Observe and analyze the imaging video segment by segment, find the location where the water output changes in the water curtain holes, and record the depth of change; By comparing and analyzing the recorded change depth with other data, we can obtain the joint development conditions and rock fragmentation of the cave wall at the location where the water volume changes.

4. A method for advanced geological prediction of underground water-sealed caverns as claimed in claim 2 or 3, characterized in that: The development of hole wall joints is analyzed based on the imaging results, and rose diagrams of joint direction and dip are drawn to analyze the lithology changes and fragmentation of the hole wall rock mass and the development direction of the dominant joints.

5. The method for advanced geological prediction of underground water-sealed caverns according to claim 1, characterized in that: The geological structures, rock type changes, seepage joints, etc. found in the water curtain holes are extended to the main cavern according to their occurrence, and their development positions and scales in the main cavern are speculated, and the engineering geology and hydrogeology conditions of the main cavern are analyzed and speculated.

6. The method for advanced geological prediction of underground water-sealed caverns according to claim 5, characterized in that: The trigonometric method is used to extend the extrapolation to the main cavern.

Images