bluuebunny/crossref_metadata_2025_split huggingface dataset:
Progressive Failure Analysis of Tianshansi Slope
Authors: Yingfa LU , Lei ZHU , Jing Qing , Wansong HUANG 
Published: November 2020

Abstract
The physical significance of the traditional slice block method analysis of a slope is presented in this paper. The strength-softening characteristics of the geomaterial are characterized by the strength reduction coefficient of the post-failure zone of the stress–strain curve of the complete process. In the study, the transfer coefficient method (TCM) hypothesis was generalized, and the partial strength reduction method (PSRM) and perfect elastoplastic model (PEPM) were employed. The progressive failure process of a slope was simulated by the proposed generalized slice block method; a critical-stress-state determination method was proposed. The safety factor of the extended slice block method was found to be closely related to deformation of the slope, and the characteristics of the critical stress state movement were revealed by the proposed generalized sequential slice block method. The unbalanced thrust and driving sliding force gradually increase and the frictional resistance gradually decreases during deformation failure. When the last slice block is in the critical stress state, complete slope failure occurs. Taking the Tieshansi slope of Huangshi City as an example, the evolution characteristics of the physical and mechanical variables during progressive failure of the slope were revealed by the proposed generalized TCM using PSRM- and PEPM-based numerical simulations. The results show that the proposed method can describe the progressive failure process of the Tieshansi slope. The emphasis of this research is on extending the traditional strength reduction slice block method so that the results are closely related to the slope deformation.
Study on dynamic response characteristics of high and steep layered rock mass slopes using a modal analysis method
Authors: Song D Q , Huang J , Liu X L , Wang E Z , Zhang J M 
Published: November 2020

Abstract
The common geological bodies found in southwest China are layered mass slopes. The modal analysis method is performed on four finite element numerical models of rock slopes, including the homogeneous slope, horizontally layered slope, bedding slope, and toppling slope to investigate the dynamic deformation characteristics of the layered slopes. Their dynamic deformation characteristics are systematically studied according to the modal characteristics of slopes. By using modal analysis, the numerical results show that a series of natural frequencies and vibration modes of the slopes can be obtained. The type of structural planes affects the natural frequency of the slopes. The values of the natural frequency of the slopes are as follows: homogeneous slope > toppling slope > horizontally layered slope > bedding slope. Weak structural planes also have an amplification effect on the dynamic deformation of the slopes according to the analyses of the relative displacement (U) of the first vibration modes of the slopes. The natural frequency has a significant impact on the dynamic deformation characteristics of the slopes. Low-order natural frequency mainly induces the overall deformation of the top slope and slope surface area, whereas the high-order natural frequency mainly induces the local deformation of the slope. Modal analysis can provide a new idea for further study of dynamic characteristics of rock slopes.
Direct shear experiment on salt rock incorporating loading rate effect
Authors: Wang Derong , Xue Bing , Li Zeng , Wang Yunxiao , Dong Lu , Fan Pengxian 
Published: November 2020

Abstract
To investigate the shear behavior of salt rock under different loading rates, direct shear testing was conducted on high-purity salt rock obtained from Pakistan using a YZW-100 apparatus. The experimental results of the shear stress, deformation, and failure characteristics of the salt rock showed that the loading rate is an essential factor influencing the shear strength parameters of the rock. When the shear loading rate was increased, the cohesion of the salt rock significantly increased; however, the internal friction angle slightly decreased, nearly remaining unchanged. The shear failure mode of the salt rock manifested by shear stress-displacement curves tended to be ductile failure with increased normal force. The residual stress of the salt rock was large, indicating its high friction-bearing capacity. The dilatancy deformation was also subjected to shear loading. The fracture section of the salt rock exhibited visible local scratch marks. These experimental results are helpful for further understanding the failure mechanism of salt rock and the stability of underground gas storage under different gas injection and production scenarios.
Feasibility analysis of using salt caverns for storage of redox flow batteries
Authors: Guodong Huang , Jie Chen , Wei Liu , He Chen 
Published: November 2020

Abstract
Renewable energy holds significant promise of replacing the conventional energy sources. However, the wind and solar energy exhibit the obvious discontinuity, instability, and uncontrollability problems. Redox flow batteries are a novel energy technology, whose most appealing features are high efficiency, long life, and reduced environmental impact. Salt rock has low porosity and permeability, and can self-heal from damage. A salt chamber after water-dissolution is considered as an excellent geological body for energy storage. This study reviews in detail the current worldwide status of salt cavern utilization. Drawing on the salt-carven oil and gas storage technology, the feasibility of storing electrolytes in salt caverns is analyzed considering the physical characteristics of salt rock deposits, and economic and environmental factors. Two medium salt caverns in Jiangsu Province were selected and used as a case study for storage for the all-vanadium flow batteries. The working principle of salt cavern is introduced, and the efficiency of energy storage of the entire system is approximately calculated. Based on the assessment of the existing salt caverns in China, it has been found that using salt caves for electrolyte storage can solve the current problems of disposing old battery electrolyte.
Experimental Study on the Engineering Characteristics of Mixed Buffer/Backfill Materials
Authors: Lei JI , Chuan-le WANG , Yang HAN , Ye-chao YOU , Guo-dong XU , Hui GONG 
Published: November 2020

Abstract
Previous studies on buffer/backfill materials have been primarily focused on certain performances, and studies on the comprehensive screening of the engineering characteristics of such materials are scarce, and to ensure the safe operation of disposal repositories, new materials are needed. Therefore, to obtain the optimal mix ratio that meets the requirements for the operation of disposal repositories, and on the basis of existing literature, the thermal conductivity, impermeability, and shear resistance of buffer/backfill materials with different mix ratios were comprehensively screened to determine the effect of different components on these abovementioned properties. The results obtained showed that the addition of starch could improve the compactness of the mixed buffer/backfill materials, increase the contact area between the particles in the material, and improve their thermal conductivity, impermeability, and shear resistance to varying degrees. The peak value of the permeability of the mixed material was attained when the sand mixing ratio was 20%. Moreover, an increase in the dry density, starch content, and graphite content resulted in an increase in the internal friction angle and cohesion force of the composite materials. As the sand mixing ratio increased, the internal friction angle of the material first increased, and then decreased as the sand mixing ratio was further increased. At the peak sand mixing ratio (~20%), a decrease in the cohesion force was observed. Based on these results and on the engineering requirements for buffer/backfill materials destined for application in disposal repositories, the optimal mix ratio was selected according to the principle of “pilot heat, re-impermeability, and post-strength,” and the recommended formula for hybrid buffer/backfill materials was obtained.
Statistical Simplification and Discrete Element Analysis of Seepage Model for Complex Fracture Network of Dam Foundation Rock Mass
Authors: Wang Shi-Min , Tan Chun , Ma Dong-He , Liu Zhong-Fu , Gao Yin , Xu Xin-Chuan 
Published: November 2020

Abstract
In this paper, a model of seepage in a fracture network is analyzed by taking the rock mass of the dam foundation of Datengxia Hydropower Station, the No. 1 Project of the Ministry of Water Resources, as an example. Complex discontinuity systems are present in the rock mass of the Datengxia Hydropower Station dam foundation, and faults, soft interlayers, and structural fracture systems intersect with one another. A multi scalar structural analytical scheme that combines the deterministic analysis of large scale geological structures (i.e., faults and weak interlayers) with the statistical simulation of random discontinuities (i.e., structural fractures) is proposed in this paper to reduce the difficulty and uncertainty of the analysis of rock masses with complex structures. In particular, a chain analytical method from dominant group definition to statistical parameters (i.e., spacing and occurrence) is formed for the structural fracture system. In this way, the analysis of rock masses with complex structures is simplified to a regular and feasible scientific problem that could be solved by rock mass simulation. We then establish a seepage model of the rock mass in dam section 29# in UDEC by adopting the above structural simplification scheme. The quantitative analysis of seepage in complex structured rock masses under normal water storage and dynamic conditions is then realized. Results show that the statistical simplification of the rock mass structure and discrete element simulation can efficiently solve the seepage analysis of complex rock masses. The negative influence of pore pressure caused by seepage on the rock mass, especially under dynamic conditions, should be emphasized for safety assurance in the stability analysis of dam foundations.
Influence of fiber-optic cable structure, sand density, and acoustic frequency on DAS amplitude response: Preliminary results
Authors: Xie Tao , Zhang Cheng-Cheng , Chen Jia-Song , Fu Ya-Ping , Dai Liang , Yin Jun , Shi Bin 
Published: November 2020

AbstractDistributed acoustic sensing (DAS) is an emerging fiber-optic technology that can turn tens of kilometers long fiber-optic cables into dense acoustic sensor arrays. This technology is expected to bring new opportunities for geologic hazard characterization and mitigation. The cable structure and installation method are two critical factors affecting the performance of a DAS system. Here, we report laboratory tests performed in a sandbox to evaluate the acoustic response of different types of cables at variable sand densities and acoustic frequencies. Our initial results indicated that complex cable packaging structures had unfavorable impacts on the DAS amplitude response whereas the influence of sand density was dependent on cable structure and acoustic frequency. Further tests with refined measurement setup will improve the understanding of the combined effects of cable type, medium density, and acoustic frequency on DAS recordings.
Wellbore stability analysis for arbitrary inclined well in anisotropic formations
Authors: Ma Tianshou , Huang Jin , Jia Lichun , Liu Yang , Qiu Yi , Zhang Yun 
Published: November 2020

Abstract
Wellbore instability is a classic rock mechanics problem encountered during drilling and completing. The traditional model for wellbore stability analysis assumes that formation rocks are homogenous, continuous, and isotropic. However, most of the deep formation rocks are naturally anisotropic. Therefore, this study proposes an anisotropic wellbore stability model for an arbitrary inclined well, considering the anisotropic elastic properties, shear strength, and in-situ stress. This model was compared to the traditional model. The equivalent mud weight of collapse pressure (EMWCP) was predicted for three types of typical in-situ stress states, such as normal faulting (NF), strike-slip faulting (SSF), and reverse faulting (RF). The results show that rock anisotropy significantly influenced EMWCP compared to the traditional model. The anisotropy of in-situ stress and shear strength increase the EMWCP, whereas the anisotropy of rock elastic properties decreases the EMWCP. The optimal well path is in the ranges of the attack angle (the angle between the borehole axis and the normal of weak planes) lower than 45°. In other words, the anisotropy shear strength is harmful to keeping wellbore stability, whereas the anisotropy of rock elastic properties is conducive. Thus, the influence of anisotropic shear strength cannot be ignored for wellbore stability analysis, whereas the influence of anisotropic elasticity can be ignored. This model provides theoretical guidance for drilling mud density optimization, well trajectory optimization, and well drilling and completion safety.
Technique and Practice on Temperature Control and Crack Prevention for RCC Dam at High Altitude in Tibet
Authors: Xiang Qian , Xiong Tao 
Published: November 2020

Abstract
The dam in the DG Hydropower Station is currently the world’s highest roller compacted concrete gravity dam. The temperature control and crack prevention of concrete under special climatic conditions have become a key technical problem in dam construction. To avoid temperature cracks in the dam, the proportion of raw materials is determined in accordance with casting time, climatic conditions, and raw material performance parameters. Furthermore, the concrete mix ratio is optimized, and concrete with high cracking resistance, relatively low hydration heat, optimal VC value, and good rolling and bleeding properties is prepared. It effectively prevents the occurrence of temperature cracks in dams and solves the technical problem of temperature control and crack prevention for RCC dam construction in high-altitude areas.
Compaction of large buffer block for disposal of high-level radioactive waste
Authors: Shengfei Cao , Yuemiao Liu , Jingli Xie , Like Ma 
Published: November 2020

Abstract
The concept model of high-level radioactive waste (HLW) repositories in deep geological media is based on a multi-barrier system. In accordance with this concept for the storage of spent nuclear fuel, the canister with the fuel should be surrounded by bentonite blocks. A useful technique for producing compacted blocks of bentonite is described in this work. These blocks were uniaxially compacted with a mold that yielded blocks with an outer diameter of 1200 mm, inner diameter of 600 mm, and angle of 45 degrees. A technique has been developed for manufacturing blocks from GMZ-Na bentonite using a large press machine. During these tests, blocks were compacted for studying different factors that affect the quality of the blocks. The blocks were also examined with respect to damage and cracks. The results from these tests revealed that the natural water content of the bentonite powder leads to several problems that affect the quality of the blocks. In the subsequent test, the blocks were manufactured with different compaction rates using powders with high water content. Samples (nine cylindrical samples in total) were taken from the two examined blocks, and the water content and the density were determined. The results revealed that the solid block is rather homogenous. This indicates that the technique of compacting bentonite blocks established in the present study is suitable for manufacturing buffer blocks.
Quantitative analysis of slope stability of drilling sites with complex topography in the Qiongdongnan continental slope
Authors: Sun Jin , Wang Dawei , Wu Shiguo , Ouyang Min , Liu Hailong 
Published: November 2020

Abstract
Due to the large slope angle and the weak strength of submarine soils, Qiongdongnan deepwater continental slopes face great instability problems. In continental slope area, evaluating the stability of the slope before drilling is important as slope instability threatens the drilling safety. Taking the Lingshui deepwater well site as an example, 2D and 3D submarine slope stability calculation models, which consider the vertical heterogeneity of soil strength, were established based on the strength reduction method and Flac3D. The vertical profile of the soil shear strength was obtained via cone penetration and geotechnical tests. The effect of returned cuttings and drilling disturbance on slope stability were analyzed, and the safety factor of the slope was calculated. In addition, the position of potential slip surfaces and the possible slip directions were analyzed. Based on this, the location of the well was determined. The results indicate that the minimum safety factor of slope, which crosses the well, is 1.32. Moreover, the risk of submarine landslide is low. One potential landslide mass exists. However, the slope near the well is stable, and the slip direction of the landslide mass does not point to the well. The returned cuttings from the borehole decrease the safety factor and increase the risk of slope instability near the well.
Discussion on Reducing the Environmental Damage Caused by Climate Change with Innovative Thinking of Financial Management
Authors: Chen Colin W.K. , Chen Yu-Ting 
Published: November 2020

Abstract
Due to the greenhouse effect caused by greenhouse gas emissions, the earth’s climate has changed, which has brought many types of environmental disasters. This study discusses the types of these environmental disasters and explores which financial instruments can be applied to reduce these environmental disasters. This study points out that abnormal climates, temperature rises, sea levels rise, and uneven rainfall distribution have led to intensified earth and rock flows and flood disasters, all of which are environmental disasters caused by climate change. The available financial instruments include environmental taxes, carbon trading, and catastrophe insurance. The implementation and effectiveness of these methods are also discussed in this study.
Study on the Chemical Reaction and Deposition Calculation of Mercury in the Atmosphere
Authors: Chen Colin W.K. , Chen Yu-Ting 
Published: November 2020

Abstract
The source-attribution of atmospheric mercury is one of the important issues for public health today. This paper discussed the assessment of chemical reaction and deposition of mercury in the atmosphere. The air quality model from the chemical reaction and atmospheric diffusion aspects simulated the mercury in the ecosystem. The deposition processes of mercury were divided into the near field and far field in the atmosphere. Two air quality models, ISTST and CAMx used for the simulation of mercury transport were introduced in this study. Details on the atmospheric diffusion and the gas-phase and aqueous-phase mercury chemistry mechanisms implemented in the model were presents in this paper. The uncertainty of simulation models such as the elemental mercury, aerosol mercury, oxidized mercury, dry deposition, and wet deposition was discussed. The results of this study will aid in the implementation of mercury transport model in the regional model.
A Comparative Study on the Development Status of Environmental Education in the United States, the United Kingdom, and Australia
Authors: Cao Qiang 
Published: November 2020

Abstract
With the rapid development of the world economy, the global environment and development problems faced by mankind have become increasingly prominent. At the expense of the environment, people have created unprecedented material wealth and promoted the rapid development of the world’s material civilization. This leads to environmental deterioration, resource consumption, and serious ecological destruction. The realization of environmentally sustainable development has become a major issue of common concern for all mankind. Environmental education is a comprehensive lifelong education with the relationship between humans and the environment as the core. According to agenda 21, “education is the decisive factor in implementing sustainable development strategies and empowering people to solve environmental and development problems. Educational behavior plays an important role in sustainable development. Its main purpose is to train people to consciously protect the environment and care for the environment by using education. Environmental protection is an important part of sustainable development, and environmental education is the decisive factor to realize environmental protection. It arouses citizens’ awareness of environmental protection, improves the quality of the whole people’s environmental protection, and finally realizes sustainable development. his paper makes a comparative study on the development status of environmental education in the United States, the United Kingdom, and Australia. By analyzing and discussing the current problems of environmental education, this paper tries to conclude the far-reaching significance of the future development of environmental education.
Study on Environmental Issues of Community Residents around Krirk University
Authors: Quan Han-Yi , Shih Kuo-Tung , Lin Chia-Jung 
Published: November 2020

Abstract
Humans enjoyed rich resources, location, climate and so on. Develop our technical civilization on this azure planet. Excessive use of natural resources leads to extreme weather changes, drought, acid rain, flood, animal extinction, and other disasters. The purpose of this study was to explore the environmental education literacy of residents living near Krirk University. This study used a questionnaire, issued 120 copies on campus, 81 copies issued outside the school. The total number of questionnaires is 201. The invalid questionnaire is 26. The effective questionnaire is 175. The results of this study are as follows: The first education level is related to environmental literacy. Second, the environmental literacy of males is higher than females. Third, the national environmental literacy from high to low is China, Thailand, Myanmar. Fourth, the age of environmental literacy from high to low is 46-55 years old, 26-35 years old, above 56 years old, 36-45 years old, 19-35 years old, under 18 years old. At last, the comparison of the educational level of parents is directly proportional to environmental literacy. The study concluded that environmental literacy is highly correlated with the level of education and provides a reference for future environmental education policy development based on the research results.