The cavability assessment of rock mass cavability and indicating the damage profile ahead of a cave-back is of great importance in the evaluation of a caving mine operation, which can influence all aspects of the mine operation. Due to the lack of access to the caved zones, our current knowledge about the damage profile in caved zones is very limited. Among the different approaches available, p...

We study the structural instability mechanism and effect of a multi-echelon support in very-deep roadways. We conduct a scale model test for analysing the structural failure mechanism and the effect of multi-echelon support of roadways under high horizontal stress. Mechanical bearing structures are classified according to their secondary stress distribution and the strength degradation of the s...

The aim of this study was to determine the energy expenditure of a group of cavers of both genders and different ages and experience during a 10 hour subterranean exploration, using portable metabolimeters. The impact of caving activity on body composition and hydration were also assessed through bioelectrical impedance, and nutritional habits of cavers surveyed. During cave activity, measured ...

This paper presents the engineering geological properties and roof control tecnology for a thick coal seam fully-mechanized face mining with hard roof conditions (THC) at the Jinhuagong Coal Mine (JCM), northwest China. The effective support working resistance and appropriate roof control technology are two critical factors for safe and productive mining in the THC. The load-estimate-method (LO...

Minor faults, subsidence columns, coal tunnels and gob are very important in coal mining because they can cause flooding accidents, broken coal beds, added fissures, and gas accumulation. All of these factors will increase coal mining risk. In addition, minor faults also affect the design of roadways. In this article, we have achieved satisfactory results in identifying minor faults, subsidence...

The key to the safe mining of thick coal seams under rivers is understanding the development patterns of fractured water-conducting zones (FWCZ) when various mining methods are used. To solve this problem, we employed numerical simulation to investigate FWCZ when slice mining and longwall caving mining are performed. When slice mining was carried out, the maximum height of the FWCZ in the highe...

Metal mines mined using the sublevel caving method often exhibit various environmental problems on ground surface. This can affect safety of production process in mining area. A numerical model Universal Distinct Element Code has been established to investigate deformation failure giving rise this underground mining. The calculations are combined with in-situ monitoring data collected over a pe...

The advancement of construction techniques and high-performance sustainable materials enables the increase span length for arch bridge. It is great importance to study theoretical ultimate Based on parabolic catenary axes, analytical solutions bridge are solved using derivation accounting strength, in-plane stability out-plane conditions, respectively. Then, use concrete, reactive powder concre...

It is estimated that one-third part of the world population is infected with the tubercle bacillus. While only a small percentage of infected individuals will develop clinical tuberculosis, each year there are approximately eight million new cases and two million deaths. Mycobacterium tuberculosis is thus responsible for more human mortality than any other single microbial species. The goals of...