نتایج جستجو برای: rock engineering

تعداد نتایج: 299671  

2007
Albert Einstein

1.INTRODUCTION Some forty years ago, most opening supports and reinforcements were designed using empirical rules defining ground loads acting on the supporting structures. This approach is still popular and interest in it has been renewed by the use of rock mass classification systems (Barton et al. 1974, Bieniawski, 1974,1976,1989). Correlations between rock mass conditions and the type of su...

Journal: :int. journal of mining & geo-engineering 2015
kayvan ghorbani mohsen zahedi ahmad asaadi

the rock masses in a construction site of underground cavern are generally not continuous, due to the presence of discontinuities, such as bedding, joints, faults, and fractures. the performance of an underground cavern is principally ruled by the mechanical behaviors of the discontinuities in the vicinity of the cavern. during underground excavation, many surrounding rock failures have close r...

2014
Wahid Ali Noor Mohammad Mohammad Tahir

This research work presents a case study of rock mass characterization on diversion tunnels at Diamer Basha Dam, Pakistan. Geological and geotechnical studies were performed to characterize the rock mass along the axis of diversion tunnel. The core specimens retrieved were tested in laboratory and physical and mechanical properties of the rock mass were determined. Detailed discontinuity survey...

2017
Kegang Li Baowei Yang Xiangxing Li

Original scientific paper Rock generally contains various micro-cracks, fissures, pores, joints, and other defects. These defects affect the mechanical properties of rock. In order to clarify the influence of native fissures on rock deformation and failure modes, a laboratory study was carried out using the fissured dolomite, and acoustic wave velocity measurement and natural water absorption t...

2017
Bo Wang Linsheng Huo Dongdong Chen Weijie Li Gangbing Song

Pre-stress degradation or looseness of rock bolts in mining or tunnel engineering threatens the stability and reliability of the structures. In this paper, an innovative piezoelectric device named a "smart washer" with the impedance method is proposed with the aim of developing a real-time device to monitor the pre-stress level of rock bolts. The proposed method was verified through tests on a ...

2008
Yadin David Anthony C. Easty

Yadin David, EdD, PE, CCE, Matthew Baretich, PE PhD, William A. Hyman, PE, ScD, Wayne Morse, and James O. Wear, MSBME, CCE, FACCE From the Biomedical Engineering Consultants, LLC, Houston, Texas (Dr David); Baretich Engineering, Inc, Fort Collins, Colorado (Dr Baretich); Department of Biomedical Engineering, Texas A&M University, College Station (Dr Hyman); Morse Medical, Linc Facility Services...

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