Results 61 to 70 of about 1,604,914 (120)

Developing a universal tunnel span classification from global tunnel databases

Deep Underground Science and Engineering, EarlyView.
A universal tunnel span classification system is introduced that incorporates tunnel span, cross‐sectional area, typical tunnel types, and intended uses. Representative flatness ratio values are also provided for each span class. The classification is derived from a comprehensive database of 450 tunnel profiles from 47 countries.
Simon Heru Prassetyo, Inzagi Suhendar, Semmy Andrew Anugerah Djawa Tagi, Bonifacio Bondan Satryojati, Dzakwan Naufal Pratama, Yeremia Sintong Damero, Yudhidya Wicaksana, Erwin Lim, Ridho Kresna Wattimena   +8 more
wiley   +1 more source

Evolution law of surrounding rock bearing circle and support technology of deep roadway

, 2023
Taking Guotun Coal Mine -670 auxiliary horizontal track roadway as the engineering background, the stress change of roadway surrounding rock is analyzed through the mechanical model of bearing circle, and the stress change of roadway surrounding rock ...
SHEN Shibao, WU Yancheng, SONG Song, ZHENG Yining, MENG Shengshi   +4 more
core   +1 more source

Study on Roof‐Control Technology for Gob‐Side Entry Retaining Under Composite Roofs

Energy Science &Engineering, EarlyView.
This study develops a roof‐control technology system for gob‐side entry retaining under composite roofs. By integrating field measurements, theoretical analysis, and numerical simulation, it reveals the spatiotemporal evolution of the plastic zone and proposes a targeted support method, providing theoretical and practical guidance for safe and ...
Dong Li, Yujiang Zhang, Yunlou Du, Haodong Zheng, Baoji Yang   +4 more
wiley   +1 more source

Pressure relief for drilling (trenching) and support technology in deep soft rock tunnels

Frontiers in Earth Science
Controlling surrounding rock stability in deep soft rock tunnels solely by increasing the support strength is challenging. The key areas where the surrounding rock of a roadway is prone to “instability” should be treated with comprehensive measures, such
Yang Ling, Xu Ying
doaj   +1 more source

Optimization of Blasting‑Induced Roof Cutting Parameters in Key Stratum and Its Application in Gob‑Side Entry Retention Technology

Energy Science &Engineering, EarlyView.
This study addresses hard roof coal seam conditions by optimizing key stratum blasting‐cutting parameters through theoretical analysis, numerical simulation, and field tests. It proposes calculation methods for blast hole spacing and delay timing based on stress wave theory, controlling roadway deformation within 35 mm, thereby enhancing resource ...
Qiong Liu, Duanxiang Fu, Hongbin Li
wiley   +1 more source

Stress Relief and Support for Stability of Deep Mining Roadway with Thick Top Coal in Hujiahe Coal Mine with the Risk of Rock Burst

Shock and Vibration, 2021
Rock burst is a typical dynamic disaster in deep underground coal mining. Based on the support problems of the deep roadways in fully mechanized caving face 401111 of Hujiahe Coal Mine suffering from rock burst in Shaanxi Province of China, the failure ...
Wenjing Liu, Deyu Qian, Xingguo Yang, Sujian Wang, Jinping Deng, Qi Cui, Zexiang Li   +6 more
doaj   +1 more source

Numerical Simulation Study on Optimization of Horizontal Sublevel Top‐Coal Caving Mining Technique for Steeply Inclined Extra‐Thick Coal Seam

Energy Science &Engineering, EarlyView.
As the sublevel height increases, the top‐coal recovery amount gradually increases, but both the top‐coal recovery rate and the thickened top‐coal recovery rate show a downward trend, and the decline in the top‐coal recovery rate is gradually increasing. The comparison indicates that the optimal sublevel height is 20 m.
Hongsheng Tu, Dingyi Hao, Wenhong Xiao, Fuhao Jiang, Shikun Xu   +4 more
wiley   +1 more source

Damage Characteristics and Stress Distribution Law of Overburden Rock in Multiple Mining of Close Coal Seams

Energy Science &Engineering, EarlyView.
This study on close coal seams shows that multi‐seam mining increases the height of the fractured zone from approximately 26 m (single upper‐seam mining) to about 49 m. When the lower seam is mined after the extraction of the upper seam, the heights of both the caved zone and the fractured zone increase by approximately two times.
Xiaoyu Wu, Lei Guo, Zedong Sun, Xiaowei Wu, Nan Zhang   +4 more
wiley   +1 more source

Human Recreation and Fire History Shape Landscape Connectivity for an Endangered Forest Carnivore

Animal Conservation, EarlyView.
Roads and trails can impede wildlife movement, but their permeability varies with human use and fire history. We combined GPS telemetry from 45 endangered southern Sierra Nevada fishers (Pekania pennanti) with smartphone‐derived human mobility data to estimate crossing probability across road and trail segments. Fishers were about 2.5 times more likely
Mark A. Ditmer, Maksim Sergeyev, Helen E. Chmura, Jody M. Tucker, Gavin M. Jones, Kari E. Norman, Ronan B. Hart, Michael K. Schwartz, Andria M. Townsend, Rebecca E. Green, Sarah L. Stock, George Wittemyer   +11 more
wiley   +1 more source

Investigation on Deformation and Failure Characteristics and Stability Control of Soft Rock Roadway Surrounding Rock in Deep Coal Mine

, 2011
Numerical simulation and field measurement were carried out to investigate into laws of deformation and movement and the evolving characteristics of the plastic region around the roadway based on engineering conditions of deep soft rock roadway in ...
Ju Cai Chang, Guang Xiang Xie
core   +1 more source