Adverse Geological Conditions Research Articles

Integrated geochemical, mineralogical, and microstructural identification of faults in tunnels and its application to TBM jamming analysis

Faults are frequently one of those adverse geological conditions that jam tunnel boring machines (TBMs). However, the identification of faults and the engineering geological analysis of the corresponding jamming accidents still lack a better understanding. In this study, a method for fault identification through integration of the microstructural, geochemical, and mineralogical characteristics of the rocks was developed. The method was applied to the TBM 2 bid section of the Central Shanxi Yellow River Diversion Project to determine the geological characteristics of the rocks using optical thin section, X-ray fluorescence, and X-ray diffraction analysis. The results of this study provide evidence for the establishment of fault-induced geochemical effects and mineral transformations. Not only were fault FT1 and the nearby fault rock successfully identified, but evidence of weakened mechanical properties of the fault rocks was also obtained. The structure and composition of the migmatitic granites were strongly altered by long-term tectonic stress fracturing and pervasive acidic fluid leaching, forming loosely fractured, poorly integrated granitic granulate-porphyroclastic rock. The fault rock is rich in clay minerals and solid graphite lubricant. The comprehensive effect of the fault rock’s characteristics, geological structure, groundwater, and ground stress led to the collapse of the weak rock within the fault zone, which was the main geological reason for the jamming accident. Finally, we proposed corresponding engineering treatment measures and subsequent excavation recommendations. The proposed method can be used for the integrated identification of faults in underground engineering and mining projects, and the geological analysis of TBM jamming accidents.

Study on Detection of the Bearing Stratum Integrity of Bored Pile Based on Transient Electromagnetic Method

To ensure the safe construction of bridge pile foundation in karst area, it is necessary to accurately detect the unfavorable geological conditions such as karst cave and soft layer before excavation. In this paper, the transient electromagnetic method is used to probe the geological conditions near the pile Y1 of an interworking main bridge in China’s Hunan Province. By arranging 5 measuring lines at the pile Y1, the voltage variation laws of 21 monitoring points on each measuring line are obtained, and the resistivity variation cloud maps at the measuring line positions are inversed. The results show that the voltage signals at line 1 and line 5 are obviously abnormal, and the resistivity varies greatly within 50 m underground depth, which indicates that there may be adverse geological conditions such as karst cave and carbonaceous limestone interlayer. Further, through on-site hole digging and sampling, it is found that the slag sample in the area above 50 m of the stratum of pile Y1 is wet, and the slag sample below 50 m is dry without argillaceous interlayer, which verifies the effectiveness of transient electromagnetic detection method. Because the transient electromagnetic detection technology does not need drilling and the detection process is convenient, it may provide a new means for quickly detecting the integrity of the bearing layer of bored cast-in-place pile in bridge construction.

Reinforcement Mechanism and Engineering Application of Weak Tailing Pond Beach by Soilbag Method

In light of the engineering characteristics of fine-grained tailings, such as their high moisture content, high compressibility, difficult deposition, and difficult consolidation, and based on the summary and analysis of the experience of tailing dam construction in China and abroad, a new comprehensive treatment technology suitable for dam construction on a weak beach, which is composed of strengthening foundation with the soilbag, subdam stabilization, and collaborative drainage, is proposed. Taking a dam construction project on the weak beach of a tailing pond in China as the research object and through the study of the reinforcement mechanism of the soft beach treated using the soilbag method, it can be seen that the soilbag body has the mechanism of strength growth by sand fixation and water permeability and constraint formation and can achieve an overall stable effect of extrusion and silt replacement, stacking and surcharge, and flexible embedding in a weak beach. Using this method, combined with relevant monitoring technology, a good demonstration of dam construction speed of up to 30 m/a and a safe dam construction height of up to 60 m on a weak beach surface is achieved in a tailing dam construction project, which provides a good reference for the design and construction of fine tailing dam engineering and the cooperative disposal of adverse geological conditions.

Field Test of In Situ Groundwater Treatment Applying Oxygen Diffusion and Bioaugmentation Methods in an Area with Sustained Total Petroleum Hydrocarbon (TPH) Contaminant Flow

Contamination of groundwater by petroleum hydrocarbons is a widespread environmental problem in many regions. Contamination of unsaturated and saturated zones could also pose a significant risk to human health. The main purpose of the study was to assess the efficiency of biodegradation of total petroleum hydrocarbon (TPH) in situ, in an area with loam and sandy loam soils, and to identify features and characteristics related to groundwater treatment in an area with a persistent flow of pollutants. We used methods of biostimulation (oxygen as stimulatory supplement) and bioaugmentation to improve water quality. Oxygen was added to the groundwater by diffusion through silicone tubing. The efficiency of groundwater treatment was determined by detailed monitoring. Implementation of the applied measure resulted in an average reduction in TPH concentration of 73.1% compared with the initial average concentration (4.33 mg/L), and in the local area, TPH content was reduced by 95.5%. The authors hope that this paper will contribute to a better understanding of the topic of groundwater treatment by in situ biodegradation of TPH. Further studies on this topic are particularly needed to provide more data and details on the efficiency of groundwater treatment under adverse geological conditions.

Study on the Influence of different factors on cutterhead shield jamming of gripper TBMs in weak rocks

In the construction of deep-buried and long-mileage tunnels, the use of tunnel boring machines (TBMs) is the preferred excavation method. However, TBMs encounter a variety of problems in adverse geological conditions. When excavating in weak rocks with high in situ stress, the large deformation of the surrounding weak rocks causes TBM jamming, which is very time consuming and expensive to deal with. In practice, the most commonly used method is the advanced geological prediction technology, and support systems are strengthened on the basis of the convergence–confinement method, which is composed of the longitudinal deformation profile (LDP), ground reaction curve, and support characteristic curve. In this work, the LDPs of surrounding weak rocks were obtained using numerical models in FLAC3D. The influence of the elastic modulus (E) of rocks, buried depth of a tunnel (BDT), and tunnel diameter on the cutterhead shield jamming of a gripper TBM was analyzed. In the analysis, the total length of the cutterhead and cutterhead shield of the gripper TBM was 4 m, and the friction between the cutterhead shield and the surrounding rocks was not considered. Results showed that increasing the overcut was the most effective method to prevent TBM jamming. Moreover, E and BDT exerted an obvious effect on the design value of the overcut. Several suggestions to prevent the cutterhead shield jamming of gripper TBMs and countermeasures to resolve such jamming in weak rocks were subsequently derived. The conclusions of this work can facilitate the selection of appropriate overcuts when designing the cutterheads of TBMs and help to prevent and control the cutterhead shield jamming of gripper TBMs in weak rocks.

Tightness of an underground energy storage salt cavern with adverse geological conditions

A micro-permeable interlayer (MPI) has been found in a salt cavern construction area of the Jintan salt cavern underground gas storage district, Jiangsu, China. The MPI has caused sealing failures of several wells. Tightness is a prerequisite of salt caverns used for energy storage. To quantifiably evaluate the tightness of gas storage salt caverns constructed in formations including an MPI, permeability testing of MPI samples and numerical simulations are carried out. The MPI permeability ranges from 1.10 × 10−16 m2 to 2.12 × 10−14 m2 with an average of 8.16 × 10−15 m2, much larger than that of the rock salt and of other interlayers at the same formation. The effects of the MPI permeability, MPI thickness, width of pillars between caverns, and MPI location on the tightness of the cavern are investigated. The permeability and the location of the MPI are the key factors affecting the cavern tightness. It is suggested to seal the MPI rather than allow it to intersect the caverns untreated in the areas containing the MPI. A rock salt layer between the MPI and the cavern with a thickness of about 5 m is proposed to seal the MPI.

Experimental Investigation on Mass Loss Characteristics of Broken Rocks with Discontinuous Gradation

This study mainly focuses on the transport process of broken rocks in geological fractures, faults, and karst conduits. Because previous research mainly focused on the influencing factors of adverse geological conditions, there is no clear understanding of the migration behavior of fillings and the formation process of pathways in the process of water inrush. An experimental testing apparatus was designed and developed to perform systematic research on the transport process of granular soils subjected to seepage flow. This system was comprised of a water supply system, acrylic glass holding device, and collection system, which could effectively be used to study the influence of discontinuous gradation and flow velocity on the permeability characteristics of loosening fillings. The experimental results show that the water inrush induced by seepage failure results from the gradual migration and loss of particles by water seepage. According to the fine-grain content and loss characteristics of the samples, the samples are divided into three types: those with a nonskeleton structure, with a dense-suspension structure, and with a void-skeleton structure. With an increase in the content of fine particles, the porosity and permeability decrease whereas the time required for water inrush of the sample gradually increases. With an increase in flow velocity, the time required for water inrush and its rate of change gradually decrease. However, the mass loss of particles does not increase with the increasing flow velocity during the same period. The research results provide a valuable reference with which to further study the mechanism of variable mass seepage in faulted and fractured rock.

Construction Risk Evaluation of Poor Geological Channels Based on Cloud Model-Improved AHP–Matter–Element Theory

In the process of economic development, the exploitation and utilization of resources has played an important role, but the subsequent post-mining collapse and the shortage of land resources have affected future reconstruction to a certain extent. Currently, there is a firm belief in sustainable development and its goals to be achieved in the future. Based on the concept of sustainable development, this paper examines the feasibility of rebuilding channels under adverse geological conditions, and studies whether there are risks and the degree of risk. According to the characteristics of the experts’ judgment language and the ambiguity and randomness between various factors, it is proposed that a cloud model is used to improve the AHP (Analytic Hierarchy Process) risk assessment method. At the same time, the traditional matter–element theory is improved through the cloud model, so that the impact of uncertainty and randomness can be comprehensively considered in the evaluation; finally, forming the risk assessment system of the cloud-based AHP and cloud-based matter–elements. The application of examples shows that, compared with the methods in the relevant literature, the evaluation results of this article are more objective, more accurate, have better applicability, and play an important guiding role in channel construction under adverse geological conditions.

Experimental study of the comprehensive technology of grouting and suspension under an operating railway in the cobble stratum

The construction technology of shield tunnelling under an operating railway in an adverse stratum is complex and risky. The existing research results mostly focus on the settlement control of the tunnel under the existing structure, but they are not adequate to provide a systematic reference for shield tunnelling under an operating railway with strict requirements on the settlement control. Based on the background of the Luoyang Rail Transit Line 2 shield passing through the Luoyi Railway, the comprehensive technology of grouting and suspension (CTGS) has been proposed, and field test and numerical simulation are used to study the effects of its application. The results show that the comprehensive technology of grouting and suspension has a significant effect on the rail settlement control of shield tunnelling under the operating railway in a cobble stratum. Using the grouting method to grout subgrade soil can improve the strength of the overlying soil layer. Using the suspension method to suspend the railway tracks can directly transfer the load to the pile foundation to avoid the subgrade bearing excessive load. CTGS combines the grouting method with the suspension method, which can be used as the preferred technology to control the influence of subgrade soil settlement on railway track surface. Compared with the similar technology, although the project cost is slightly higher, CTGS significantly ensures railway safety during the construction process, which can help keep the railway operation free from interference during the construction period and has obvious comprehensive benefits. CTGS has an important reference value for the safety control of shield tunnelling construction with the risky source under adverse geological conditions such as a sandy cobble stratum.

RISK ANALYSIS OF MAJOR ENGINEERING GEOLOGICAL HAZARDS FOR SICHUAN-TIBET RAILWAY IN THE PHASE OF FEASIBILITY STUDY

The Sichuan-Tibet Railway is the most challenging railway project ever in the world. The project region is characterized by various adverse geological conditions including active tectonic movement, intensive mega faults, abrupt topographic relief and frequent geological disasters. Therefore, the construction of this project is challenged by complex geological disaster risks from both ground surface and underground. This study comprehensively and quantitatively analyzes the ground surface and underground geological risks along the Sichuan-Tibet Railway, and further evaluates their consequential influences on the project so as to support its feasibility study. The risk analysis utilizes abundant spatial-temporal data, and various approaches including three-dimensional structure modeling, numerical modeling, statistical modeling, dynamic modeling, time series modeling and spatial distribution modeling. The results show that there are three areas concentrated with high ground surface geological hazards risk along the Sichuan-Tibet railway, namely the Xianshuihe fault zone, the Jinshajiang fault zone and the eastern Himalayan syntaxis area. However, ground surface engineering risks of this project are significantly reduced, because its underground tunnels are over 80% of the total railway line length. The universal quantitative risk assessment models are developed for major underground engineering geological risks, including fault activities, rock bursts and large deformations. For several major tunnels such as the Yigong tunnel, risks of typical individual underground geological hazards(e.g. rock burst and large deformation) as well as the integrated risk, are quantitatively evaluated. The results show that both surface and subsurface engineering risks are significant and can threaten the safety of project. This study provides a scientific and technical support for the feasibility study of the Sichuan-Tibet Railway, and is also expected to be a reference for major engineering geological risk control for similar line engineering projects around the world.

Research on Application of Multi-factor Surrounding Rock Pressure Calculation Theory in Engineering

Based on the multi-factor surrounding rock pressure calculation theory, the values of surrounding rock pressure and construction safety and stability coefficients corresponding to different construction methods required by engineering design and construction could be quickly and conveniently calculated with the derived general formula, so as to guide and optimize the design and construction scheme. In this paper, the influence of lateral load coefficient on surrounding rock pressure was analyzed and verified, and the calculation method and application range of lateral load coefficient were proposed. Meanwhile, according to the multi-factor surrounding rock pressure calculation theory, an arched precast member was proposed, which was assembled into an optimal and reasonable honeycomb-like stress structure, and applied in the support of tunnel and underground space. It could improve the construction technology of composite lining by taking the advantage of the common load bearing of surrounding rock and support. In addition, with the theory, the application of arched precast member in the support of deep foundation pit has simplified the setting of lateral support of deep foundation pit in the horizontal direction, which is an innovative construction method for deep foundation pit support using prefabricated assembly components. Certainly, the calculation theory should be further studied, and the dynamic change of surrounding rock pressure after excavation under various adverse geological conditions should be accurately analyzed and verified by means of monitoring and measurement, which should be reasonably connected with the current Code for popularization and application. It is hoped that the study of the calculation theory and its application in engineering practice can provide useful guidance and help for the design and construction of tunnel and underground space.

Diagnosing tunnel collapse sections based on TBM tunneling big data and deep learning: A case study on the Yinsong Project, China

The Yinsong Water Diversion Project in China’s northeast region contains a 20 km long tunnel section, which was drilled by a tunnel boring machine (TBM) and monitored in real time to generate continuously measured data. During the tunnel construction, 18 tunnel wall collapse failures were documented. This study reviews the boring performance of the TBM during these failures based on the field-collected data for the penetration rate, cutterhead rotation speed, torque, and thrust force, which were obtained at a 1-second interval. The main task in this study includes the development of a time series forecasting (TSF) approach combined with a deep belief network (DBN) that predicts the torque associated with a given penetration rate and rotation speed through a parameter called the drilling efficiency index, TPI, in a neural network. This study begins with a pilot case of a tunnel collapse that eventually caused the TBM construction to be abandoned. In this case, the TSF&DBN algorithm clearly identifies the deviations of the observed TPI values from those given by the neural network, indicating the successful prediction of an unfavorable geological condition. In addition, the cases of 13 other collapse sections are reviewed; of these, 11 clearly exhibit similar performance to the pilot case, whereas the remaining 2 provide no sufficient indications to exclude possible unstable roofs. This preliminary study shows that a systematic and high-quality TBM performance database can be useful in diagnosing adverse geological conditions in conjunction with the proper use of big data and machine learning techniques.

Hard-rock TBM jamming subject to adverse geological conditions: Influencing factor, hazard mode and a case study of Gaoligongshan Tunnel

Adverse geological conditions, the major challenge of tunnel construction, affect the excavation rate and even cause the hard-rock tunnel boring machine (TBM) jamming. Firstly, 121 cases of TBM jamming are analyzed in this study (detailed information can be found in Appendix A). The influencing factors of TBM jamming are studied and the hazard modes are classified into six categories. The selection of shield TBM takes up 77.69% of the 121 cases, occurring in 94 cases. In terms of adverse geological conditions, the fractured zone is one of the most commonly met adverse geological conditions for TBM jamming cases. In addition, groundwater often plays an indirect catalytic role in jamming hazards. It is found that collapse of surrounding rocks is the most common hazard mode for TBM jamming, appearing in 52 cases. Secondly, Gaoligongshan Tunnel, one of the longest railway tunnels in China, is presented as a representative case. The possibility, geological conditions and locations of TBM jamming occurring in the Gaoligongshan Tunnel are studied in site, which verifies the results of case statistics and the geological laws proposed above. The specific steps to predict and control TBM jamming in Gaoligongshan Tunnel are proposed. Finally, the lessons learned are summarized, and the countermeasures for TBM jamming are developed regarding three stages of TBM tunnel construction. The results of this study provide a reference for the mechanism of TBM jamming and share certain practical countermeasures to ensure a safe and efficient TBM excavation in adverse geological conditions.

Experimental study on damage evolution characteristics of segment structure of shield tunnel with cracks based on acoustic emission information

Cracks are constantly observed in segments due to adverse geological conditions and loads during shield construction. However, crack propagation can have a negative impact on the stress deformation of the segment structures in the long run. Revealing the characteristics of energy release during crack propagation can effectively reflect the damage evolution process. Based on an investigation of segment cracks in a subway tunnel project, this paper conducts an in-depth analysis of AE data of segments through similar model tests, and explores the influence of cracks of different lengths, quantities and positions on the damage evolution of segments of shield tunnels. The results show that cracks reduce the overall stiffness of the structure when compared with that of a segment ring with no prepared cracks, and the elastic bearing range increases slightly, while the plastic bearing range decreases obviously. With the increase of the length and number of prepared cracks, the number of ladders of AE events decreases and the height of ladders increases, and the number of AE events of segments increases continuously at the critical point of instability. The damage of segments appears earlier, and the development process of the damage and is relatively gentle if cracks are located at the arch waist. By contrast, the damage of segments is more serious if cracks are located at the arch roof and arch bottom. The results provide theoretical basis for design optimization, disease analysis and evaluation of shield tunnel.

Structural damage assessment of mountain tunnels in fault fracture zone subjected to multiple strike-slip fault movement

Fault fracture zones are adverse geological conditions often encountered in the constructions of mountain tunnels. Extensive structural damage to the mountain tunnels in adjacent to the fault fracture zones has been documented in the past earthquakes. In current work, three-dimensional numerical model of a water conveyance tunnel crossing multiple active strike-slip faults was established to assess the structural damage with consideration of four primary influence factors: the magnitude of fault movement, the distance between adjacent fault planes, the tunnel-fault intersection angle and the mechanical properties of the rock mass in the fault fracture zone. Two quantitative damage indices, namely, the overall structural damage index and the concrete lining crack width, are proposed in this study to investigate the structural integraty and the serviceability of the water conveyance tunnel subjected to fault movements. The numerical results indicate that the cross-sectional damage of the tunnels primarily concentrated in the vicinities of the fault planes, and the boundaries between the fault and the competent rock. With the increase of the distance between adjacent fault planes, the structural damage of the tunnel in the region near the center of the fault fracture zone rapidly decreases. The tunnel-fault intersection angle also significantly affects the performance of the tunnel under fault movement. Moreover, the increase of surrounding rock mass stiffness in the fault fracture zone reduces the extension but increases the severity of damage to the tunnel lining. Overall, the numerical results of this study provide a better understanding of the response of mountain tunnels under multiple strike-slip fault movement.

Risk Analysis for the Sustainable Hydropower Development in Nepal

Development of hydropower projects involves a large amount of initial investment. Unlike other construction projects, hydropower projects are riskier to undertake since, the projects are large in size, linear in nature and involve many parties and stakeholders. The projects are facing cost overrun, schedule slippage, environmental, and social problems due to the various risk factors associated with the projects, which have to be identified and analysed so that the issues can be mitigated for the sustainable hydropower development in the country. This research involved identification and analysis of risk factors, which led to cost overrun and impact on the social and ecological environment due to the development of hydropower. The risk factors were identified through a questionnaire survey to the experts and literature review. The identified risks were analysed qualitatively considering both the probability of occurrence of the risk and its impact on the project and were prioritised with the help of P-I Matrix, also known as Look-Up table. The survey results revealed that the critical risk factors for the sustainable hydropower development are land acquisition problem, public disorder, adverse geological conditions, resettlement and rehabilitation, flooding, change in laws and regulations, labour disputes and strikes, and sedimentation problem. This study shall be helpful to the developers and project managers to have a better risk response plan for sustainable hydropower project development.

Fundamentals of modern ground control management in Australian underground coal mines

Underground coal mining is inherently hazardous, with uncontrolled ground failure regarded as one of only several critical risks for multiple fatality events. Development, implementation and management of overarching systems and procedures for maintaining strata control is an important step to mitigating the impact of ground failure hazards at a mine site operational level. This paper summarised the typical pro-active ground control management system (PGCMS) implemented in various Australian underground coal mines. Australia produces approximately 100 million tonnes a year of metallurgical and thermal coal from approximately 30 of the world’s safest longwall mines operating in New South Wales and Queensland. The increased longwall productivity required to achieve both high levels of safety and profitability, places significant emphasis on the reliability of pro-active ground control management for longwall mining operations. Increased depths, adverse geological conditions, elevated variable stress regimes and weaker ground conditions, coupled with an industry wide need for increased development rates continue to make ground control management challenging. Ground control management is not only about ground support and pillar design though but also a structured process that requires a coordinated effort from all levels of the workforce to both minimise the occurrence of adverse geotechnical events and mitigate the potential risks when they do occur. The PGCMS presented in this paper is proven to provide both a safer and more productive mine environment through minimisation of unplanned delays. The critical elements of the method are presented in detail and demonstrate the utility and value of a ground control management system that has potential for implementation in underground coal mining globally.

Comprehensive Geophysical Investigation and Analysis of Lining Leakage for Water-Rich Rock Tunnels: A Case Study of Kaiyuan Tunnel, Jinan, China

Leakage of lining structure is one of the main geological disasters of the tunnel, which brings heavy economic losses and casualties. Aiming at the problem of lining leakage of the Kaiyuan Tunnel in Jinan, this research has carried out a geological survey, conducted statistics, and classification of the leakage situation of the Kaiyuan Tunnel. The causes and main control factors of various types of seepage are analyzed. To locate the leakage accurately, electrical resistivity tomography, transient electromagnetic method, and ground penetrating radar are used to carry out comprehensive geophysical exploration. Two catchment zones and fractured zones are determined based on the existing geological topographic maps, geological profile maps, and geological analysis results. Transient electromagnetic detection results coincide with the known fractured zones, which confirms the existence of fractured zones and defines the scope of fractured zones. Moreover, the detection results based on ground penetrating radar show that the main adverse geological conditions inlining and surrounding rock are water diversion area, hidden water diversion area and surrounding rock fragmentation area. Subsequently, three kinds of grouting material, ultra-fine cement, ordinary Portland cement, and polymer cement, were selected for seepage control of the 800–900 m and 1310–1330 m test sections for plugging treatment. The grouting effect was analyzed and evaluated based on ground penetrating radar detection and field working conditions. Especially, the grouting radar detection shows that the grouting effect of polymer cement slurry is ideal, the grout in the water conduction area is basically filled, and the lining cracking and damage have been significantly repaired and improved. This paper verifies the accuracy and good feasibility of the interpretation criteria of comprehensive geophysical detection for typical lining defects, which can be popularized and applied in relevant tunnels and underground projects.

Geologic data collection and assessment techniques in coal mining for ground control

The identification and mitigation of adverse geologic conditions are critical to the safety and productivity of underground coal mining operations. To anticipate and mitigate adverse geologic conditions, a formal method to evaluate geotechnical factors must be established. Each mine is unique and has its own separate approach for defining what an adverse geological condition consists of. The collection of geologic data is a first critical step to creating a geological database to map these hazards efficiently and effectively. Many considerations must be taken into account, such as lithology of immediate roof and floor strata, seam height, gas and oil wells, faults, depressions in the mine floor (water) and increases in floor elevation (gas), overburden, streams and horizontal stress directions, amongst many other factors. Once geologic data is collected, it can be refined and integrated into a database that can be used to develop maps showing the trend, orientation, and extent of the adverse geological conditions. This information, delivered in a timely manner, allows mining personnel to be proactive in mine planning and support implementations, ultimately reducing the impacts of these features. This paper covers geologic exploratory methods, data organization, and the value of collecting and interpreting geologic information in coal mines to enhance safety and production. The implementation of the methods described above has been proven effective in predicting and mitigating adverse geologic conditions in underground coal mining. Consistent re-evaluation of data collection methods, geologic interpretations, mapping procedures, and communication techniques ensures continuous improvement in the accuracy of predictions and mitigation of adverse geologic conditions. Providing a concise record of the work previously done to track geologic conditions at a mine will allow for the smoothest transition during employee turnover and transitions. With refinements and standardization of data collection methods, such as those described in this paper, along with improvement in technology, the evaluation of adverse geologic conditions will evolve and continue to improve the safety and productivity of underground coal mining.

地质雷达探测技术在不良地质处理中的应用——阿曼拉斯玛卡兹原油储罐工程地下喀斯特岩溶空洞解决方案

地质雷达探测技术在不良地质处理中的应用——阿曼拉斯玛卡兹原油储罐工程地下喀斯特岩溶空洞解决方案