Shunyu Yue, Ruifeng Miao, Huihang Cheng, Maohua Zhong, Xiujun Yang
The Shenzhen–Zhongshan Bridge is a 24-km-long bridge and tunnel system, including a 6.8-km-long super cross section subsea tunnel. To solve the smoke exhaust problem of a super large cross-section subsea tunnel, the tunnel has a new smoke exhaust system that combines a horizontal smoke exhaust cross section at the top and sidewall smoke exhaust holes. In order to evaluate the potential fire hazards of this type of tunnel, a 1:30 tunnel model was established and 140 small-scale experiments on underwater tunnel fires were conducted. By changing the fire power, fire location, and fan operation mode, different scenarios of submarine immersed tunnel fire were simulated and the related key parameters such as fire smoke diffusion behavior and smoke temperature distribution were studied. On this basis, the optimal smoke control strategy was proposed for different fire scenarios. The research results indicate that the new smoke exhaust system can fully utilize the smoke flow characteristics, significantly improve smoke exhaust efficiency, and increase available evacuation time, thus further enhancing the fire safety of super large cross-section subsea tunnels.
{"title":"Small-scale fire tests in the underwater tunnel section model with new sidewall smoke extraction","authors":"Shunyu Yue, Ruifeng Miao, Huihang Cheng, Maohua Zhong, Xiujun Yang","doi":"10.1002/dug2.12102","DOIUrl":"https://doi.org/10.1002/dug2.12102","url":null,"abstract":"<p>The Shenzhen–Zhongshan Bridge is a 24-km-long bridge and tunnel system, including a 6.8-km-long super cross section subsea tunnel. To solve the smoke exhaust problem of a super large cross-section subsea tunnel, the tunnel has a new smoke exhaust system that combines a horizontal smoke exhaust cross section at the top and sidewall smoke exhaust holes. In order to evaluate the potential fire hazards of this type of tunnel, a 1:30 tunnel model was established and 140 small-scale experiments on underwater tunnel fires were conducted. By changing the fire power, fire location, and fan operation mode, different scenarios of submarine immersed tunnel fire were simulated and the related key parameters such as fire smoke diffusion behavior and smoke temperature distribution were studied. On this basis, the optimal smoke control strategy was proposed for different fire scenarios. The research results indicate that the new smoke exhaust system can fully utilize the smoke flow characteristics, significantly improve smoke exhaust efficiency, and increase available evacuation time, thus further enhancing the fire safety of super large cross-section subsea tunnels.</p>","PeriodicalId":100363,"journal":{"name":"Deep Underground Science and Engineering","volume":"3 2","pages":"247-254"},"PeriodicalIF":0.0,"publicationDate":"2024-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/dug2.12102","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141326802","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jianguo Wang, Heping Xie, Chunfai Leung, Xiaozhao Li
This issue covers the papers on two special themes: (1) Mineral resources from deep sea—Science and Engineering and (2) Planning and development of underground space and infrastructure for sustainable and liveable cities.
The special theme of “Mineral resources from deep sea—Science and Engineering” is on the exploration and transport of mineral resources from deep sea. The mineral resources are rich in deep sea and their rational development and utilization can meet the needs of social and economic development. The security and strategy of deep-sea mineral resource exploration are important to the successful development of high-quality marine economy. However, deep-sea science and mineral resource exploitations confront many unknowns. This special theme aims to provide a platform for the exploration and exchange in research and engineering progresses and six papers were received, including four Original Research Papers, one Review Paper, and one Short Communication. The authors are from Australian Catholic University, National University of Singapore, Ocean University of China, China University of Mining and Technology, and so on.
The idea for this special theme originates from the First Young Scholars Symposium on Deep-Sea Science and Mineral Resources (2022). Deep Underground Science and Engineering (DUSE) collaborated with the conference organizer and launched a call for a special theme: Mineral Resources from Deep Sea—Science and Engineering. Guest Editors of this special theme are Prof. Jianhua Yue (China University of Mining and Technology), Prof. Yonggang Jia (Ocean University of China), Prof. Chunhui Tao (Second Institute of Oceanography, Ministry of Natural Resources, China), Prof. Haiyan Yang (China University of Mining and Technology), Prof. Honglei Shen (China University of Mining and Technology), and Prof. Zhuangcai Tian (China University of Mining and Technology).
The special theme of “Planning and development of underground space and infrastructure for sustainable and liveable cities” is on city development from the prospects of underground space and infrastructure. The utilization of urban underground space for accommodating urban functions, through developing underground commercial, transport, and public infrastructure, has been a common practice in urban development in past decades. Increased migration of populations to cities brings many urbanization problems, such as inadequate land and infrastructure, air and noise pollution, traffic congestion, and degraded environmental quality, thus providing an opportunity for underground infrastructure as an attractive solution to these problems. As a relatively new dimension of cities, underground space has been widely recognized as a valuable resource for city development. Urban underground space utilization is an effective way of developing and redesigning cities, promoting sustainable urban development, and building liveable cities. Underground infrastruc
{"title":"Deep sea mineral resources and underground space as well as infrastructure for sustainable and liveable cities","authors":"Jianguo Wang, Heping Xie, Chunfai Leung, Xiaozhao Li","doi":"10.1002/dug2.12104","DOIUrl":"https://doi.org/10.1002/dug2.12104","url":null,"abstract":"<p>This issue covers the papers on two special themes: (1) Mineral resources from deep sea—Science and Engineering and (2) Planning and development of underground space and infrastructure for sustainable and liveable cities.</p><p>The special theme of “Mineral resources from deep sea—Science and Engineering” is on the exploration and transport of mineral resources from deep sea. The mineral resources are rich in deep sea and their rational development and utilization can meet the needs of social and economic development. The security and strategy of deep-sea mineral resource exploration are important to the successful development of high-quality marine economy. However, deep-sea science and mineral resource exploitations confront many unknowns. This special theme aims to provide a platform for the exploration and exchange in research and engineering progresses and six papers were received, including four Original Research Papers, one Review Paper, and one Short Communication. The authors are from Australian Catholic University, National University of Singapore, Ocean University of China, China University of Mining and Technology, and so on.</p><p>The idea for this special theme originates from the First Young Scholars Symposium on Deep-Sea Science and Mineral Resources (2022). <i>Deep Underground Science and Engineering</i> (DUSE) collaborated with the conference organizer and launched a call for a special theme: Mineral Resources from Deep Sea—Science and Engineering. Guest Editors of this special theme are Prof. Jianhua Yue (China University of Mining and Technology), Prof. Yonggang Jia (Ocean University of China), Prof. Chunhui Tao (Second Institute of Oceanography, Ministry of Natural Resources, China), Prof. Haiyan Yang (China University of Mining and Technology), Prof. Honglei Shen (China University of Mining and Technology), and Prof. Zhuangcai Tian (China University of Mining and Technology).</p><p>The special theme of “Planning and development of underground space and infrastructure for sustainable and liveable cities” is on city development from the prospects of underground space and infrastructure. The utilization of urban underground space for accommodating urban functions, through developing underground commercial, transport, and public infrastructure, has been a common practice in urban development in past decades. Increased migration of populations to cities brings many urbanization problems, such as inadequate land and infrastructure, air and noise pollution, traffic congestion, and degraded environmental quality, thus providing an opportunity for underground infrastructure as an attractive solution to these problems. As a relatively new dimension of cities, underground space has been widely recognized as a valuable resource for city development. Urban underground space utilization is an effective way of developing and redesigning cities, promoting sustainable urban development, and building liveable cities. Underground infrastruc","PeriodicalId":100363,"journal":{"name":"Deep Underground Science and Engineering","volume":"3 2","pages":"129-130"},"PeriodicalIF":0.0,"publicationDate":"2024-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/dug2.12104","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141326798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study delves into the latest advancements in machine learning and deep learning applications in geothermal resource development, extending the analysis up to 2024. It focuses on artificial intelligence's transformative role in the geothermal industry, analyzing recent literature from Scopus and Google Scholar to identify emerging trends, challenges, and future opportunities. The results reveal a marked increase in artificial intelligence (AI) applications, particularly in reservoir engineering, with significant advancements observed post-2019. This study highlights AI's potential in enhancing drilling and exploration, emphasizing the integration of detailed case studies and practical applications. It also underscores the importance of ongoing research and tailored AI applications, in light of the rapid technological advancements and future trends in the field.
{"title":"Application of machine learning and deep learning in geothermal resource development: Trends and perspectives","authors":"Abdulrahman Al-Fakih, Abdulazeez Abdulraheem, Sanlinn Kaka","doi":"10.1002/dug2.12098","DOIUrl":"10.1002/dug2.12098","url":null,"abstract":"<p>This study delves into the latest advancements in machine learning and deep learning applications in geothermal resource development, extending the analysis up to 2024. It focuses on artificial intelligence's transformative role in the geothermal industry, analyzing recent literature from Scopus and Google Scholar to identify emerging trends, challenges, and future opportunities. The results reveal a marked increase in artificial intelligence (AI) applications, particularly in reservoir engineering, with significant advancements observed post-2019. This study highlights AI's potential in enhancing drilling and exploration, emphasizing the integration of detailed case studies and practical applications. It also underscores the importance of ongoing research and tailored AI applications, in light of the rapid technological advancements and future trends in the field.</p>","PeriodicalId":100363,"journal":{"name":"Deep Underground Science and Engineering","volume":"3 3","pages":"286-301"},"PeriodicalIF":0.0,"publicationDate":"2024-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/dug2.12098","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141107648","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Meeting the climate change mitigation targets will require a substantial shift from fossil to clean fuels in the heating sector. Heat pumps with deep borehole exchangers are a promising solution to reduce emissions. Here the thermal behavior of deep borehole exchangers (DBHEs) ranging from 1 to 2 km was analyzed for various heat flow profiles. A strong correlation between thermal energy extraction and power output from DBHEs was found, also influenced by the heating profile employed. Longer operating time over the year typically resulted in higher energy production, while shorter one yielded higher average thermal power output, highlighting the importance of the choice of heating strategy and system design for optimal performance of DBHEs. Short breaks in operation for regenerating the borehole, for example, with waste heat, proved to be favorable for the performance yielding an overall heat output close to the same as with continuous extraction of heat. The results demonstrate the usefulness of deep boreholes for dense urban areas with less available space. As the heat production from a single DBHE in Finnish conditions ranges from half up to even a few GWh a year, the technology is best suitable for larger heat loads.
{"title":"Performance analysis of deep borehole heat exchangers for decarbonization of heating systems","authors":"Andreas E. D. Lund","doi":"10.1002/dug2.12101","DOIUrl":"10.1002/dug2.12101","url":null,"abstract":"<p>Meeting the climate change mitigation targets will require a substantial shift from fossil to clean fuels in the heating sector. Heat pumps with deep borehole exchangers are a promising solution to reduce emissions. Here the thermal behavior of deep borehole exchangers (DBHEs) ranging from 1 to 2 km was analyzed for various heat flow profiles. A strong correlation between thermal energy extraction and power output from DBHEs was found, also influenced by the heating profile employed. Longer operating time over the year typically resulted in higher energy production, while shorter one yielded higher average thermal power output, highlighting the importance of the choice of heating strategy and system design for optimal performance of DBHEs. Short breaks in operation for regenerating the borehole, for example, with waste heat, proved to be favorable for the performance yielding an overall heat output close to the same as with continuous extraction of heat. The results demonstrate the usefulness of deep boreholes for dense urban areas with less available space. As the heat production from a single DBHE in Finnish conditions ranges from half up to even a few GWh a year, the technology is best suitable for larger heat loads.</p>","PeriodicalId":100363,"journal":{"name":"Deep Underground Science and Engineering","volume":"3 3","pages":"349-357"},"PeriodicalIF":0.0,"publicationDate":"2024-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/dug2.12101","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140966766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Grace E. Belshaw, Elisabeth Steer, Yukun Ji, Herwin Azis, Benyamin Sapiie, Bagus Muljadi, Veerle Vandeginste
Geothermal energy extraction often results in the release of naturally occurring carbon dioxide (CO2) as a byproduct. Research on carbon storage using volcanic rock types other than basalt under both acidic and elevated temperature conditions has been limited so far. Our study uses batch reactor experiments at 100°C to investigate the dissolution of andesite rock samples obtained from an active geothermal reservoir in Sumatra (Indonesia). The samples are subjected to reactions with neutral-pH fluids and acidic fluids, mimicking the geochemical responses upon reinjection of geothermal fluids, either without or with dissolved acidic gases, respectively. Chemical elemental analysis reveals the release of Ca2+ ions into the fluids through the dissolution of feldspar. The overall dissolution rate of the rock samples is 2.4 × 10–11 to 4.2 × 10–11 mol/(m2 · s), based on the Si release during the initial 7 h of the experiment. The dissolution rates are about two orders of magnitude lower than those reported for basaltic rocks under similar reaction conditions. This study offers valuable insights into the potential utilization of andesite reservoirs for effective CO2 storage via mineralization.
{"title":"Fluid-rock interaction experiments with andesite at 100°C for potential carbon storage in geothermal reservoirs","authors":"Grace E. Belshaw, Elisabeth Steer, Yukun Ji, Herwin Azis, Benyamin Sapiie, Bagus Muljadi, Veerle Vandeginste","doi":"10.1002/dug2.12097","DOIUrl":"10.1002/dug2.12097","url":null,"abstract":"<p>Geothermal energy extraction often results in the release of naturally occurring carbon dioxide (CO<sub>2</sub>) as a byproduct. Research on carbon storage using volcanic rock types other than basalt under both acidic and elevated temperature conditions has been limited so far. Our study uses batch reactor experiments at 100°C to investigate the dissolution of andesite rock samples obtained from an active geothermal reservoir in Sumatra (Indonesia). The samples are subjected to reactions with neutral-pH fluids and acidic fluids, mimicking the geochemical responses upon reinjection of geothermal fluids, either without or with dissolved acidic gases, respectively. Chemical elemental analysis reveals the release of Ca<sup>2+</sup> ions into the fluids through the dissolution of feldspar. The overall dissolution rate of the rock samples is 2.4 × 10<sup>–11</sup> to 4.2 × 10<sup>–11</sup> mol/(m<sup>2</sup> · s), based on the Si release during the initial 7 h of the experiment. The dissolution rates are about two orders of magnitude lower than those reported for basaltic rocks under similar reaction conditions. This study offers valuable insights into the potential utilization of andesite reservoirs for effective CO<sub>2</sub> storage via mineralization.</p>","PeriodicalId":100363,"journal":{"name":"Deep Underground Science and Engineering","volume":"3 3","pages":"369-382"},"PeriodicalIF":0.0,"publicationDate":"2024-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/dug2.12097","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141000301","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Internal solitary wave (ISW), as a typical marine dynamic process in the deep sea, widely exists in oceans and marginal seas worldwide. The interaction between ISW and the seafloor mainly occurs in the bottom boundary layer. For the seabed boundary layer of the deep sea, ISW is the most important dynamic process. This study analyzed the current status, hotspots, and frontiers of research on the interaction between ISW and the seafloor by CiteSpace. Focusing on the action of ISW on the seabed, such as transformation and reaction, a large amount of research work and results were systematically analyzed and summarized. On this basis, this study analyzed the wave–wave interaction and interaction between ISW and the bedform or slope of the seabed, which provided a new perspective for an in-depth understanding of the interaction between ISW and the seafloor. Finally, the latest research results of the bottom boundary layer and marine engineering stability by ISW were introduced, and the unresolved problems in the current research work were summarized. This study provides a valuable reference for further research on the hazards of ISW to marine engineering geology.
{"title":"Interaction between internal solitary waves and the seafloor in the deep sea","authors":"Zhuangcai Tian, Jinjian Huang, Jiaming Xiang, Shaotong Zhang, Jinran Wu, Xiaolei Liu, Tingting Luo, Jianhua Yue","doi":"10.1002/dug2.12095","DOIUrl":"10.1002/dug2.12095","url":null,"abstract":"<p>Internal solitary wave (ISW), as a typical marine dynamic process in the deep sea, widely exists in oceans and marginal seas worldwide. The interaction between ISW and the seafloor mainly occurs in the bottom boundary layer. For the seabed boundary layer of the deep sea, ISW is the most important dynamic process. This study analyzed the current status, hotspots, and frontiers of research on the interaction between ISW and the seafloor by CiteSpace. Focusing on the action of ISW on the seabed, such as transformation and reaction, a large amount of research work and results were systematically analyzed and summarized. On this basis, this study analyzed the wave–wave interaction and interaction between ISW and the bedform or slope of the seabed, which provided a new perspective for an in-depth understanding of the interaction between ISW and the seafloor. Finally, the latest research results of the bottom boundary layer and marine engineering stability by ISW were introduced, and the unresolved problems in the current research work were summarized. This study provides a valuable reference for further research on the hazards of ISW to marine engineering geology.</p>","PeriodicalId":100363,"journal":{"name":"Deep Underground Science and Engineering","volume":"3 2","pages":"149-162"},"PeriodicalIF":0.0,"publicationDate":"2024-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/dug2.12095","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141008219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Maoyi Mao, Xiaowei Yang, Chun Liu, Tao Zhao, Hui Liu
Shield tunnel, composed of several segments, is widely used in urban underground engineering. When the tunnel is under load, relative displacement occurs between adjacent segments. In the past, distributed optical fiber sensing technology was used to perform strain monitoring, but there is an urgent need to determine how to transform strain into displacement. In this study, optical frequency domain reflectometry was applied in laboratory tests. Aiming at the shear process and center settlement process of shield tunnel segments, two kinds of quantitative calculation methods were put forward to carry out a quantitative analysis. Meanwhile, the laboratory test process was simulated numerically utilizing the discrete element numerical analysis method. Optical fiber, an atypical geotechnical material, was innovatively applied for discrete element modeling and numerical simulation. The results show that the measured displacement of the dial gauge, the calculated results of the numerical model, and the displacement quantitatively calculated from the optical fiber data agree with each other in general. The latter two methods can potentially be utilized in engineering application of deformation monitoring at shield tunnel joints, but need to be further calibrated and adjusted in detail.
{"title":"Deformation monitoring at shield tunnel joints: Laboratory test and discrete element simulation","authors":"Maoyi Mao, Xiaowei Yang, Chun Liu, Tao Zhao, Hui Liu","doi":"10.1002/dug2.12092","DOIUrl":"https://doi.org/10.1002/dug2.12092","url":null,"abstract":"Shield tunnel, composed of several segments, is widely used in urban underground engineering. When the tunnel is under load, relative displacement occurs between adjacent segments. In the past, distributed optical fiber sensing technology was used to perform strain monitoring, but there is an urgent need to determine how to transform strain into displacement. In this study, optical frequency domain reflectometry was applied in laboratory tests. Aiming at the shear process and center settlement process of shield tunnel segments, two kinds of quantitative calculation methods were put forward to carry out a quantitative analysis. Meanwhile, the laboratory test process was simulated numerically utilizing the discrete element numerical analysis method. Optical fiber, an atypical geotechnical material, was innovatively applied for discrete element modeling and numerical simulation. The results show that the measured displacement of the dial gauge, the calculated results of the numerical model, and the displacement quantitatively calculated from the optical fiber data agree with each other in general. The latter two methods can potentially be utilized in engineering application of deformation monitoring at shield tunnel joints, but need to be further calibrated and adjusted in detail.","PeriodicalId":100363,"journal":{"name":"Deep Underground Science and Engineering","volume":" 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140685856","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Junjie Zhao, Diyuan Li, Jian Zhou, D. J. Armaghani, Aohui Zhou
Rock fragmentation is an important indicator for assessing the quality of blasting operations. However, accurate prediction of rock fragmentation after blasting is challenging due to the complicated blasting parameters and rock properties. For this reason, optimized by the Bayesian optimization algorithm (BOA), four hybrid machine learning models, including random forest, adaptive boosting, gradient boosting, and extremely randomized trees, were developed in this study. A total of 102 data sets with seven input parameters (spacing‐to‐burden ratio, hole depth‐to‐burden ratio, burden‐to‐hole diameter ratio, stemming length‐to‐burden ratio, powder factor, in situ block size, and elastic modulus) and one output parameter (rock fragment mean size, X50) were adopted to train and validate the predictive models. The root mean square error (RMSE), the mean absolute error (MAE), and the coefficient of determination () were used as the evaluation metrics. The evaluation results demonstrated that the hybrid models showed superior performance than the standalone models. The hybrid model consisting of gradient boosting and BOA (GBoost‐BOA) achieved the best prediction results compared with the other hybrid models, with the highest R2 value of 0.96 and the smallest values of RMSE and MAE of 0.03 and 0.02, respectively. Furthermore, sensitivity analysis was carried out to study the effects of input variables on rock fragmentation. In situ block size (XB), elastic modulus (E), and stemming length‐to‐burden ratio (T/B) were set as the main influencing factors. The proposed hybrid model provided a reliable prediction result and thus could be considered an alternative approach for rock fragment prediction in mining engineering.
{"title":"Performance evaluation of rock fragmentation prediction based on RF‐BOA, AdaBoost‐BOA, GBoost‐BOA, and ERT‐BOA hybrid models","authors":"Junjie Zhao, Diyuan Li, Jian Zhou, D. J. Armaghani, Aohui Zhou","doi":"10.1002/dug2.12089","DOIUrl":"https://doi.org/10.1002/dug2.12089","url":null,"abstract":"Rock fragmentation is an important indicator for assessing the quality of blasting operations. However, accurate prediction of rock fragmentation after blasting is challenging due to the complicated blasting parameters and rock properties. For this reason, optimized by the Bayesian optimization algorithm (BOA), four hybrid machine learning models, including random forest, adaptive boosting, gradient boosting, and extremely randomized trees, were developed in this study. A total of 102 data sets with seven input parameters (spacing‐to‐burden ratio, hole depth‐to‐burden ratio, burden‐to‐hole diameter ratio, stemming length‐to‐burden ratio, powder factor, in situ block size, and elastic modulus) and one output parameter (rock fragment mean size, X50) were adopted to train and validate the predictive models. The root mean square error (RMSE), the mean absolute error (MAE), and the coefficient of determination () were used as the evaluation metrics. The evaluation results demonstrated that the hybrid models showed superior performance than the standalone models. The hybrid model consisting of gradient boosting and BOA (GBoost‐BOA) achieved the best prediction results compared with the other hybrid models, with the highest R2 value of 0.96 and the smallest values of RMSE and MAE of 0.03 and 0.02, respectively. Furthermore, sensitivity analysis was carried out to study the effects of input variables on rock fragmentation. In situ block size (XB), elastic modulus (E), and stemming length‐to‐burden ratio (T/B) were set as the main influencing factors. The proposed hybrid model provided a reliable prediction result and thus could be considered an alternative approach for rock fragment prediction in mining engineering.","PeriodicalId":100363,"journal":{"name":"Deep Underground Science and Engineering","volume":"1 s1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140699963","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
With recent technological advancements, tunnel boring machines (TBM) have developed and exhibited high performance in large diameters and weak ground conditions. Tunnels are crucial structures that significantly influence the timelines of highway and railway projects. Therefore, the construction of tunnels with TBMs becomes a preferred option. In this study, a comparative analysis between TBM and the New Austrian Tunneling Method (NATM) for tunnel construction is performed in the construction of the T1 tunnel with a diameter of 13 m, which is the longest tunnel in the Eşme‐Salihli section of Ankara‐İzmir High‐Speed Railway Project (Türkiye). The selection of TBM type, measures taken in problematic sections, and application issues of TBM are discussed. The impact of correct description of geological and geotechnical conditions on both selection and performance of TBM is presented. An earth pressure balanced type TBM is chosen for the construction of the T1 tunnel. Because of the additional engineering measures taken before excavation in problematic areas, the tunnel was completed with great success within the initially planned timeframe. From this point of view, this study is an important case and may contribute to worldwide tunneling literature.
{"title":"Assessment for shallow and large tunnel construction in weak ground conditions: Application of tunnel boring machines","authors":"S. Karahan, C. Gokceoglu","doi":"10.1002/dug2.12083","DOIUrl":"https://doi.org/10.1002/dug2.12083","url":null,"abstract":"With recent technological advancements, tunnel boring machines (TBM) have developed and exhibited high performance in large diameters and weak ground conditions. Tunnels are crucial structures that significantly influence the timelines of highway and railway projects. Therefore, the construction of tunnels with TBMs becomes a preferred option. In this study, a comparative analysis between TBM and the New Austrian Tunneling Method (NATM) for tunnel construction is performed in the construction of the T1 tunnel with a diameter of 13 m, which is the longest tunnel in the Eşme‐Salihli section of Ankara‐İzmir High‐Speed Railway Project (Türkiye). The selection of TBM type, measures taken in problematic sections, and application issues of TBM are discussed. The impact of correct description of geological and geotechnical conditions on both selection and performance of TBM is presented. An earth pressure balanced type TBM is chosen for the construction of the T1 tunnel. Because of the additional engineering measures taken before excavation in problematic areas, the tunnel was completed with great success within the initially planned timeframe. From this point of view, this study is an important case and may contribute to worldwide tunneling literature.","PeriodicalId":100363,"journal":{"name":"Deep Underground Science and Engineering","volume":"224 19","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140704580","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Bo-wen Du, Haohan Liang, Yuhang Wang, Junchen Ye, X. Tan, Weizhong Chen
It is crucial to predict future mechanical behaviors for the prevention of structural disasters. Especially for underground construction, the structural mechanical behaviors are affected by multiple internal and external factors due to the complex conditions. Given that the existing models fail to take into account all the factors and accurate prediction of the multiple time series simultaneously is difficult using these models, this study proposed an improved prediction model through the autoencoder fused long‐ and short‐term time‐series network driven by the mass number of monitoring data. Then, the proposed model was formalized on multiple time series of strain monitoring data. Also, the discussion analysis with a classical baseline and an ablation experiment was conducted to verify the effectiveness of the prediction model. As the results indicate, the proposed model shows obvious superiority in predicting the future mechanical behaviors of structures. As a case study, the presented model was applied to the Nanjing Dinghuaimen tunnel to predict the stain variation on a different time scale in the future.
{"title":"ALSTNet: Autoencoder fused long‐ and short‐term time‐series network for the prediction of tunnel structure","authors":"Bo-wen Du, Haohan Liang, Yuhang Wang, Junchen Ye, X. Tan, Weizhong Chen","doi":"10.1002/dug2.12081","DOIUrl":"https://doi.org/10.1002/dug2.12081","url":null,"abstract":"It is crucial to predict future mechanical behaviors for the prevention of structural disasters. Especially for underground construction, the structural mechanical behaviors are affected by multiple internal and external factors due to the complex conditions. Given that the existing models fail to take into account all the factors and accurate prediction of the multiple time series simultaneously is difficult using these models, this study proposed an improved prediction model through the autoencoder fused long‐ and short‐term time‐series network driven by the mass number of monitoring data. Then, the proposed model was formalized on multiple time series of strain monitoring data. Also, the discussion analysis with a classical baseline and an ablation experiment was conducted to verify the effectiveness of the prediction model. As the results indicate, the proposed model shows obvious superiority in predicting the future mechanical behaviors of structures. As a case study, the presented model was applied to the Nanjing Dinghuaimen tunnel to predict the stain variation on a different time scale in the future.","PeriodicalId":100363,"journal":{"name":"Deep Underground Science and Engineering","volume":"17 12","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140743374","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}