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Spring Dance Concert 2025 Playbill, Providence College Department Of Theatre, Dance, & Film Apr 2025

Spring Dance Concert 2025 Playbill, Providence College Department Of Theatre, Dance, & Film

Playbill and Promotion

Providence College Department of Theatre, Dance, & Film

Angell Blackfriars Theatre

Spring Dance Concert 2025

Friday, April 25, 2025, 7:30 pm

Saturday, April 26, 2025, 2 pm

Photo by Jim Coleman

Dancer: Grace Sittig

Artistic Director, Nina Kossler

Lighting Designer, Michael Clark Wonson

Choreography: Kiley Vallee, Allison Renaud, Jade Bocciarelli, Emma Daigneau, Olivia Krupa, Gabriella Girard, Heidy Guzman, Alyssa Rago, Julianna Martin, Caroline Guanci, Grace McEvoy

Dancers: Emma Daigneau, Ella Ford, Gabriella Girard, Elizabeth Graney, Riley Joyce, Julianna Martin, Grace McEvoy, Allison Renaud, Kiley Vallee, Noel Rose DeRosa, Taylor Gifford, Helena Gillin, Heidy Guzman, Emma Preston, Caroline Puccini, …


Spring Dance Concert 2025 Poster, Providence College Department Of Theatre, Dance, & Film Apr 2025

Spring Dance Concert 2025 Poster, Providence College Department Of Theatre, Dance, & Film

Playbill and Promotion

Providence College Department of Theatre, Dance, & Film

Angell Blackfriars Theatre

Spring Dance Concert 2025

Friday, April 25, 2025, 7:30 pm

Saturday, April 26, 2025, 2 pm

Photo by Jim Coleman

Dancer: Grace Sittig


As-994-25 Resolution To Call On Cal Poly's President To Sign The American Association Of Colleges And Universities Public Statement 'A Call For Constructive Engagement', Executive Committee Apr 2025

As-994-25 Resolution To Call On Cal Poly's President To Sign The American Association Of Colleges And Universities Public Statement 'A Call For Constructive Engagement', Executive Committee

Academic Senate Resolutions

The Academic Senate of Cal Poly endorses the Public Statement by AAC&U 'A Call for Constructive Engagement'; and further resolves that the Academic Senate calls on the Cal Poly President to join other higher education leaders in California and across the United States and sign the Public Statement from the AAC&U 'A Call for Constructive Engagement.'


Athletic Attendance Research, Emily E. Mousso Apr 2025

Athletic Attendance Research, Emily E. Mousso

Research and Creativity Symposium

Athletics play a significant role in college communities, providing entertainment, camaraderie, and purpose for students and fans alike. This study examines attendance trends at University of Mary Washington (UMW) home softball games, analyzing factors that may influence spectator turnout. Using a dataset spanning from 2015 to 2024, this research explores attendance numbers in relation to variables such as temperature, time of game, day of the week, opponent type, and UMW’s win percentage. A linear regression analysis conducted in IBM SPSS identified temperature and day of the week as the only statistically significant factors impacting attendance, with p-values of 0.007 and …


Mui Wo With Friends, Taila Patterson Apr 2025

Mui Wo With Friends, Taila Patterson

2024-25 Postcards

Postcard from Taila Patterson, during the Linfield University Semester Abroad Program at Hong Kong Baptist University in China.


Tracy Bryant For Wku Staff Senate, Tracy Bryant Apr 2025

Tracy Bryant For Wku Staff Senate, Tracy Bryant

Staff Council

Campaign email soliciting votes for Tracy Bryant


Margin In The Consulting Industry: A Consultant's Perspective, Bracken Snyder Apr 2025

Margin In The Consulting Industry: A Consultant's Perspective, Bracken Snyder

ASEM Capstones

2025 ASEM 620 Capstone Project


The Role Of Ai In Risk Management: Benefits, Challenges, And Adoption Strategies, Lukas Ludwig Apr 2025

The Role Of Ai In Risk Management: Benefits, Challenges, And Adoption Strategies, Lukas Ludwig

Honors Projects in Information Systems and Analytics

This study explores the role of artificial intelligence (AI) in risk management, focusing on its integration within business operations. The primary objective of this research is to examine both the potential benefits and associated risks of adopting AI technologies, with a specific emphasis on data security, ethical concerns, and governance. A mixed methodology was employed, combining a comprehensive literature review on AI's applications and limitations with qualitative interviews conducted with professionals from various industries, including risk management, higher education, and IT development. The findings highlight key challenges in AI adoption, such as data privacy issues, bias in AI algorithms, and …


Amicus Brief Of Center For Civil Rights And Critical Justice In Support Of Appellant, Jessica Levin, Melissa Lee, Ronald A. Peterson Law Clinic Apr 2025

Amicus Brief Of Center For Civil Rights And Critical Justice In Support Of Appellant, Jessica Levin, Melissa Lee, Ronald A. Peterson Law Clinic

Center for Civil Rights and Critical Justice Advocacy

No abstract provided.


The Student Movement Volume 109 Issue 22: Cardinals Bid Farewell To A Nest In Bloom, Ayanda Dewa, Gersh William, Alyssa Caruthers, Melanie Webb, Callie Carlsen, Kaara Harris, Abby Shim, Anna Rybachek, Natalie Mendonça, Amelia Stefanescu, Lexie Dunham, Addison Randall Apr 2025

The Student Movement Volume 109 Issue 22: Cardinals Bid Farewell To A Nest In Bloom, Ayanda Dewa, Gersh William, Alyssa Caruthers, Melanie Webb, Callie Carlsen, Kaara Harris, Abby Shim, Anna Rybachek, Natalie Mendonça, Amelia Stefanescu, Lexie Dunham, Addison Randall

The Student Movement V. 109 (2024-2025)

HUMANS

Next Stop, The World: A Final Goodbye from Our Senoirs, Ayanda Dewa

Humans of the Year, Gersh William

AUSA 2025-26 Senator Projects, Alyssa Caruthers

ARTS & ENTERTAINMENT

"Til It Happens To You": SAAM and a Song, Melanie Webb

NEWS

Andrews Observes SAAM with Campus Activities, Callie Carlsen

Sabbath School Quarterly Disclaimer Addresses Domestic Violence Concerns, Kaara Harris

IDEAS

Dear Daniel, Abby Shim

PULSE

The Benefits of Crying, Anna Rybachek

Therapeutic Pathways to Healing for Assault Victims, Natalie Mendonça

Lamson Maintenance Concerns, Anna Rybacheck and Amelia Stefanescu

Support Your Local Libraries: Part 2!, Lexie Dunham

Matcha Makes a Scene on …


Table Of Contents, The Editors Apr 2025

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.


Research On Underground Coal Gasification From 2023 To 2024: A Systematic Review, Qin Yong, Yi Tongsheng, Wang Lingxia Apr 2025

Research On Underground Coal Gasification From 2023 To 2024: A Systematic Review, Qin Yong, Yi Tongsheng, Wang Lingxia

Coal Geology & Exploration

Background The industrialization of underground coal gasification (UCG) technology presents a potential solution for securing the supply of clean energy. The latest wave of exploration into UCG is currently gaining momentum. Methods This review systematically organizes domestic and international literature, expatiates the advances in research on UCG from 2023 to 2024, analyzes the primary challenges in its development, and proposes key areas for future exploration. Advances Transformative technological advancements in the development and utilization of coal energy based on UCG have been proposed. The development of an integrated, synergistic UCG – coalbed methane – carbon capture, utilization, and storage (UCG–CBM–CCUS) …


Evolutionary Pattern And A Calculation Method Of In Situ Gas Pressure Based On Pressure-Retaining Coal Cores, Gao Mingzhong, Song Jie, Cui Pengfei, Li Yongcheng, Wang Zhipeng, Zhou Xuemin, Li Ju, Hao Zongxin, Hao Haichun Apr 2025

Evolutionary Pattern And A Calculation Method Of In Situ Gas Pressure Based On Pressure-Retaining Coal Cores, Gao Mingzhong, Song Jie, Cui Pengfei, Li Yongcheng, Wang Zhipeng, Zhou Xuemin, Li Ju, Hao Zongxin, Hao Haichun

Coal Geology & Exploration

Objective and Methods The in situ gas pressure of coal seams represents a crucial parameter for the safe production of coal mines and the assessment of coalbed methane (CBM) resources. To overcome current limitations in determining the in situ gas pressure, such as prolonged measurement cycles and the influence of multiple parameters on the measurement results, this study conducted isothermal adsorption and volumetric expansion desorption experiments on pressure-retaining coal cores with varying moisture contents using a self-constructed experimental system for gas pressure evolution in pressure-retaining coal cores. As a result, the evolutionary pattern of gas pressure in pressure-retaining coal cores …


Key Technologies For Surface Control Of Gas Dynamic Disasters In Coal Mines And Their Application, Wang Bo, Xu Fengyin, Liu Wenge, Shao Sihua, Wang Ning, Wen Jiandong, Cheng Guoxi, Qu Zhenghui, Xie Yadong, Han Jiaye, Li Zhi, Xu Bo, Yang Weihua, Zhang Yiteng, Li Changxing Apr 2025

Key Technologies For Surface Control Of Gas Dynamic Disasters In Coal Mines And Their Application, Wang Bo, Xu Fengyin, Liu Wenge, Shao Sihua, Wang Ning, Wen Jiandong, Cheng Guoxi, Qu Zhenghui, Xie Yadong, Han Jiaye, Li Zhi, Xu Bo, Yang Weihua, Zhang Yiteng, Li Changxing

Coal Geology & Exploration

Objective and Significance As the coal mining depth increases, coal mining faces increasingly prominent challenges including coal and gas outbursts, rock bursts, and compound dynamic disasters. Deepening the understanding of disaster-causing mechanisms and developing diversified prevention and control technologies are significant for the safe production of coal mines. Employing the key technologies for coalbed methane (CBM) production to control gas-related dynamic disasters is an inevitable course for the safe production of coal mines. However, large-scale, suitable technology systems are yet to be developed. Methods From the perspective of the application of key technologies for surface CBM production, this study systematically …


Microseismic Monitoring And Assessment Of Segmented Hydraulic Fracturing Of Horizontal Wells In Coal Seam Roofs, Li Quangui, Peng Shuyue, Liang Yunpei, Li Wenxi, Qian Yanan, Cheng Chunhui, Yu Changjun, Zhan Jinfei Apr 2025

Microseismic Monitoring And Assessment Of Segmented Hydraulic Fracturing Of Horizontal Wells In Coal Seam Roofs, Li Quangui, Peng Shuyue, Liang Yunpei, Li Wenxi, Qian Yanan, Cheng Chunhui, Yu Changjun, Zhan Jinfei

Coal Geology & Exploration

Background Microseismic monitoring, a non-destructive monitoring technique, has been extensively applied in the hydraulic fracturing performance assessment of coal seams. However, little attention is paid to the vertical wave velocity gradients in media in the same layer during the construction of layered wave velocity models. This leads to limited precision of travel time calculation and microseismic source localization, thus affecting the assessment accuracy of the hydraulic fracturing of coal seams. Objective and Methods Based on the coal seam segmented hydraulic fracturing project in a mine in Anhui, this study proposes an improved velocity model based on the Universal Kriging interpolation …


Reflections And Implementation Strategies For Constructing A Standard System For Deep Coalbed Methane Exploration And Exploitation, Chen Xinjun, Liu Zengqin, Shen Baojian, Zhao Shihu, Zhang Jiaqi, Ye Jincheng Apr 2025

Reflections And Implementation Strategies For Constructing A Standard System For Deep Coalbed Methane Exploration And Exploitation, Chen Xinjun, Liu Zengqin, Shen Baojian, Zhao Shihu, Zhang Jiaqi, Ye Jincheng

Coal Geology & Exploration

Objective Deep coalbed methane (CBM; burial depths: > 1500 m) in China holds considerable resource potential. As a strategic clean energy, deep CBM is exhibiting increasingly high value of exploitation and utilization. This is of great practical significance for China’s energy structure transformation and the achievement of peak carbon dioxide emissions and carbon neutrality in the country. In recent years, breakthroughs have been made in deep CBM exploration in basins such as Ordos, Sichuan, and Junggar, with a single-well daily gas production exceeding 100 000 m3, marking the initial achievement of large-scale deep CBM exploitation. However, the existing standard …


Dynamic Gas Supply Mechanism And Theoretical Production Modes Of Free Gas-Rich Deep Coal Reservoirs, Chen Shida, Zhang Taiyuan, Tang Dazhen, Xu Hao, Tao Shu, Li Song, Tang Shuling Apr 2025

Dynamic Gas Supply Mechanism And Theoretical Production Modes Of Free Gas-Rich Deep Coal Reservoirs, Chen Shida, Zhang Taiyuan, Tang Dazhen, Xu Hao, Tao Shu, Li Song, Tang Shuling

Coal Geology & Exploration

Objective and Methods The production processes of adsorbed and free gases and the dynamic partitioning mechanism behind the production efficiency of both gas types are critical scientific issues to be addressed urgently in the exploration and production of deep coalbed methane (CBM). Based on the test and assay data of cores from exploration wells, this study systematically analyzed the theoretical production of deep CBM resources. By integrating the building of mathematical and numerical models, carbon isotope monitoring of methane, and the analysis of production curves, this study revealed the spatiotemporal evolutionary processes of production-induced pressure drop expansion, adsorbed gas desorption, …


An Experimental Study Of Ch4 Displacement By Co2 Under Varying Initial Reservoir Pressures, Xu Jiang, Jiang Shiyu, Peng Shoujian, Wang Zhonghui, Chen Jiaxuan, Niu Huiting Apr 2025

An Experimental Study Of Ch4 Displacement By Co2 Under Varying Initial Reservoir Pressures, Xu Jiang, Jiang Shiyu, Peng Shoujian, Wang Zhonghui, Chen Jiaxuan, Niu Huiting

Coal Geology & Exploration

Objective This study aims to reveal the evolutionary patterns of reservoir parameters during the CO2-enhanced coalbed methane (CO2-ECBM) recovery and the impact of initial reservoir pressure on CBM recovery by gas injection. Methods Based on the multi-field coupling-based physical simulation experiment system of gas injection into coal seams for production growth, this study conducted experiments of CH4 displacement by CO2 under a constant gas injection pressure of 2.0 MPa and initial reservoir pressures of 1.5 MPa, 1.0 MPa, and 0.5 MPa. Accordingly, this study explored the spatiotemporal evolutionary patterns of multiphysical field parameters such …


Parameter Optimization For Multistage Horizontal Well Fracturing Based On Multi-Cluster Perforation For Deep Coal Measure Gas: A Case Study Of The Jurassic Baijiahai Area In The Junggar Basin, Wang Bo, Jin Chenghong, Liu Jiang, Wang Zhiwei, Li Shenjian, Sheng Mao Apr 2025

Parameter Optimization For Multistage Horizontal Well Fracturing Based On Multi-Cluster Perforation For Deep Coal Measure Gas: A Case Study Of The Jurassic Baijiahai Area In The Junggar Basin, Wang Bo, Jin Chenghong, Liu Jiang, Wang Zhiwei, Li Shenjian, Sheng Mao

Coal Geology & Exploration

Objective The multistage horizontal well fracturing based on multi-cluster perforation has emerged as an effective approach for the efficient production of deep coal-measure gas (CMG). However, deep coals feature unique rock mechanical properties, fluid loss characteristics of reservoirs, and microfracture developmental characteristics, which differ significantly from those of unconventional shales, tight sandstones, and shallow coals. As a result, existing fracturing experience cannot be directly applied, highlighting the investigation of fracturing parameter optimization tailored for deep CMG production.Methods Focusing on deep CMG reservoirs in the Baijiahai area within the Junggar Basin, this study constructed a model of multistage horizontal well …


Measures And Effects Of Eco-Geological Restoration In Well No.4 In The Muli Mining Area, Qinghai Province, China, Zhao Xin, Wang Tong, Wang Weichao, Li Congcong, Li Fei, Jiang Zhikun, Li Jin Apr 2025

Measures And Effects Of Eco-Geological Restoration In Well No.4 In The Muli Mining Area, Qinghai Province, China, Zhao Xin, Wang Tong, Wang Weichao, Li Congcong, Li Fei, Jiang Zhikun, Li Jin

Coal Geology & Exploration

Objective The Muli mining area, located in the hinterland of the Qilian Mountains, Qinghai Province, serves as the source of the Datong River—a major tributary of the Yellow River. This area falls within the alpine permafrost region, exhibiting a sensitive, fragile ecosystem. In the early 21st century, disordered coal mining in this area has caused ecological damage. This has notably posed four challenges in the ecological restoration of well No.4 in this area: (1) high, steep, and unstable slopes of spoil heaps; (2) a large volume of water accumulating in mining pits; (3) permafrost excavation and destruction, and (4) land …


Advances In Research On Lithium In Coal-Bearing Strata And Its Isotopes, Zhang Yun, Wei Yingchun, Cao Daiyong, Li Xin, Jin Liangliang, Dong Bo, Wang Xin Apr 2025

Advances In Research On Lithium In Coal-Bearing Strata And Its Isotopes, Zhang Yun, Wei Yingchun, Cao Daiyong, Li Xin, Jin Liangliang, Dong Bo, Wang Xin

Coal Geology & Exploration

Significance Lithium serves as a significant strategic metal in emerging industries, and lithium isotopes have become crucial geochemical tracers due to their pronounced mass-dependent fractionation effects. Therefore, lithium minerals in coal-bearing strata have emerged as a priority in recent exploration of strategic metallic mineral resources. Investigating the isotopic composition and variation of lithium in coal-bearing strata helps reveal the sources, migration, and enrichment process of lithium while also providing a theoretical basis for lithium exploration and exploitation in coal-bearing strata. Advances This study offers a summary of advances in research on lithium in coal-bearing strata and its isotopes from three …


Multi-Field Information Fusion-Based Analysis Of The Macroscopic And Mesoscopic Damage Evolution And Location Identification Of Caving And Water-Conducting Fracture Zones For Mining Overburden, Wei Jiangbo, Wang Shuangming, Liu Lang, Wei Baoning, Chong Deyu, Liu Zhizhen, Li Dongkui, Zhuang Dengdeng, Zhou Jing Apr 2025

Multi-Field Information Fusion-Based Analysis Of The Macroscopic And Mesoscopic Damage Evolution And Location Identification Of Caving And Water-Conducting Fracture Zones For Mining Overburden, Wei Jiangbo, Wang Shuangming, Liu Lang, Wei Baoning, Chong Deyu, Liu Zhizhen, Li Dongkui, Zhuang Dengdeng, Zhou Jing

Coal Geology & Exploration

Objective For the coal mining areas in the middle reaches of the Yellow River, there is an urgent need to determine the failure characteristics of the mining overburden and the spatial structural evolution of caving and water-conducting fracture zones in the overburden, which is recognized as the major challenge in coal mining through gangue grouting filling in goaves. Methods To accurately identify the locations of the caving and water-conducting fracture zones in the mining overburden, this study investigated mining face 42205 in the Liangshuijing Coal Mine in northern Shaanxi Province. Using drilling data, this study constructed a numerical model of …


Intelligent Identification Of The Acoustic Emission Characteristics And Crack Propagation States During Of Coal Failure Based On The Nrbo-Xgboost Model, Zhang Tianjun, Cao Xinshuang, Song Shuang, He Suinan, Xue Yilun, Liu Guoying, Chen Juntao Apr 2025

Intelligent Identification Of The Acoustic Emission Characteristics And Crack Propagation States During Of Coal Failure Based On The Nrbo-Xgboost Model, Zhang Tianjun, Cao Xinshuang, Song Shuang, He Suinan, Xue Yilun, Liu Guoying, Chen Juntao

Coal Geology & Exploration

Objective The dynamic hazards of coals are intimately associated with the complexity and uncertainty of coal failure, while accurately identifying the propagation states of coal cracks serves as a critical approach to investigating the instability failure of coals. However, the current identification methods based on the physical quantities of acoustic emission suffer from slow speeds and low efficiency, failing to meet the demand for safe, efficient, and intelligent mining of coal mines. Methods To achieve the intelligent identification of the crack propagation states of coals, this study constructed an optimization model based on the Newton-Raphson-based optimizer (NRBO) and the eXtreme …


Effects Of Coal Seam Dip Angle On Asymmetric Load Transfer Paths In The Overburden Of Inclined Stopes, Zhu Kaipeng, Luo Shenghu, Xie Panshi, Li Zhilin, Fan Juan, Tian Chengyang, Yi Leilei, Xu Hui Apr 2025

Effects Of Coal Seam Dip Angle On Asymmetric Load Transfer Paths In The Overburden Of Inclined Stopes, Zhu Kaipeng, Luo Shenghu, Xie Panshi, Li Zhilin, Fan Juan, Tian Chengyang, Yi Leilei, Xu Hui

Coal Geology & Exploration

Objectives The coal seam dip angle is recognized as the root cause of far more complex load transfer paths in the overburden of inclined stopes compared to those of common coal seams. A clear understanding of the effects of the coal seam dip angle on the load transfer paths holds great significance for the stability control of surrounding rocks in inclined coal seams. Methods Based on the engineering background of a certain coal mine in Xinjiang, this study investigated the asymmetric deformations and failure of the overburden in inclined stopes using physical similar material simulation experiments, finite element numerical simulations, …


Operation Strategy Simulation Of The Heating System For Moderately Deep Geothermal Resources, Zhao Yongzhe, Zhao Baofeng, Hu Zhenyang, Gou Li, Du Dingshan, Liu Chenglu Apr 2025

Operation Strategy Simulation Of The Heating System For Moderately Deep Geothermal Resources, Zhao Yongzhe, Zhao Baofeng, Hu Zhenyang, Gou Li, Du Dingshan, Liu Chenglu

Coal Geology & Exploration

Background The active utilization of moderately deep geothermal resources for heating serves as a critical measure to achieve the goals of peak carbon dioxide emissions and carbon neutrality. Meanwhile, the effectiveness of the operation strategies of the heating system using these resources directly influences heating performance and significantly affects the energy consumption of the heating system. It is necessary to prevent resource waste while utilizing geothermal energy. Methods Based on a heating project using moderately deep geothermal resources in the Guanzhong Basin, Shaanxi Province, this study established a dynamic simulation model using the TRNSYS transient simulation software. Then, this study …


Fracture Activation In The Overburden And Aquiclude Stability Under The Mining Of Close-Distance Coal Seams, Cao Jian, Su Haitao, Wang Chao, Li Jianwei, Li Liang, Mao Xuwei Apr 2025

Fracture Activation In The Overburden And Aquiclude Stability Under The Mining Of Close-Distance Coal Seams, Cao Jian, Su Haitao, Wang Chao, Li Jianwei, Li Liang, Mao Xuwei

Coal Geology & Exploration

Background In the Jurassic coalfield of northern Shaanxi Province, the repeated mining of close-distance coal seams exacerbates the activation of fractures in the overburden. This is prone to cause aquiclude instability, leading to groundwater loss. Methods This study aims to reveal the characteristics of fractures in the overburden and the aquiclude stability in the mining of close-distance coal seams. Using a method combining measurement statistics, physical simulations using similar materials, and theoretical analysis, this study proposed categorizing primary coal-rock combinations based on the water-preserved mining of close-distance coal seams in the Jurassic coalfield of northern Shaanxi. Additionally, this study analyzed …


Inversion Of Electric Field Component EX In The Sotem Method Based On The Improved Particle Swarm Optimization Algorithm, Zhang Jifeng, Chen Changjian, Li Yuteng, You Xiran, Ma Ziben Apr 2025

Inversion Of Electric Field Component EX In The Sotem Method Based On The Improved Particle Swarm Optimization Algorithm, Zhang Jifeng, Chen Changjian, Li Yuteng, You Xiran, Ma Ziben

Coal Geology & Exploration

Objective The inversion of the horizontal electric field component in the grounded-source short offset transient electromagnetic (SOTEM) method using traditional algorithms is prone to fall into local extrema. To address this challenge, this study proposed an improved particle swarm optimization (PSO) algorithm that integrates the center of gravity reverse learning strategy. Methods Based on the center of gravity reverse learning strategy, the improved PSO algorithm can dynamically adjust learning factors and the value of the adaptive inertia weight, thus improving the global search capability and convergence efficiency effectively. The performance of the improved PSO algorithm was verified using the typical …


Characteristics Of Dynamic Mode Ⅱ Fracture Of Frozen Saturated Sandstones Under Varying Low Temperatures And Loading Rates, Zhao Tao, Cui Zhao, Jia Hailiang, Yang Guangyu Apr 2025

Characteristics Of Dynamic Mode Ⅱ Fracture Of Frozen Saturated Sandstones Under Varying Low Temperatures And Loading Rates, Zhao Tao, Cui Zhao, Jia Hailiang, Yang Guangyu

Coal Geology & Exploration

Background Investigating the mode Ⅱ fracture of frozen saturated sandstones under dynamic disturbances, including changes in their critical stress intensity factor (SIF; i.e., fracture toughness) and energy dissipation mechanisms, is crucial for the safe excavation of frozen wellbores through drilling and blasting in coal mines. Methods Using a split Hopkinson pressure bar (SHPB), this study conducted experiments on the dynamic mode Ⅱ fracture of a sandstone specimen using the short core in compression (SCC) method (also referred to as dynamic SCC experiments) under varying temperatures and loading rates. Accordingly, this study analyzed the SIF versus time curves of the frozen …


An Experimental Study On The Yield Strength Of Cement Grout For Grouting In The Limestone Area Of A Coal Seam Floor, Zou Jun, Guo Yan, Gui Herong, Wang Weimin, Chen Zhenlin, Liu Faming, Dai Yanan, Hu Yang, Chen Zengbao, Li Jun, Gao Chuan, Li Heng Apr 2025

An Experimental Study On The Yield Strength Of Cement Grout For Grouting In The Limestone Area Of A Coal Seam Floor, Zou Jun, Guo Yan, Gui Herong, Wang Weimin, Chen Zhenlin, Liu Faming, Dai Yanan, Hu Yang, Chen Zengbao, Li Jun, Gao Chuan, Li Heng

Coal Geology & Exploration

Objective and Methods In recent years, regional grouting through ground directional drilling has become the preferred technique for water disaster prevention and control in floor limestones in a coal mining area. In grouting engineering, the diffusion radius of cement grout, which has always received wide attention, is constrained by multiple factors including the shear yield strength (yield strength for short) and specific gravity of cement grout, along with grouting pressure. The diffusion radius in turn influences the implementation effects of on-site grouting engineering. Among its controlling factors, the yield strength of cement grout cannot be tested on site. Given this, …


Critical Technical Parameters Of Large-Diameter Multi-Stage Casing Drilling For Mine Rescue, Xu Chao, Yao Ningping, Jiang Lei, Tian Hongjie, Liu Zhi, Zhu Ning Apr 2025

Critical Technical Parameters Of Large-Diameter Multi-Stage Casing Drilling For Mine Rescue, Xu Chao, Yao Ningping, Jiang Lei, Tian Hongjie, Liu Zhi, Zhu Ning

Coal Geology & Exploration

Objective This study aims to meet the needs of mine rescue in cave-in accidents occurring in narrow underground spaces and to address the contradiction between equipment miniaturization and the drilling of large-diameter rescue boreholes under complex collapse conditions. Based on the goal of constructing a 60-m-long rescue passageway, this study developed a dual-power, composite drilling process based on multi-stage casing drilling technology for large-diameter horizontal rescue boreholes under complex collapse conditions. Furthermore, this study investigated the critical drilling parameters, aiming to provide a basis for the function development and parameter formulation of rescue equipment. Methods This study designed supporting three-stage …