Abstract In the process of longwall top coal caving, selection caving interval along advancing direction working face has an important effect on recovery. To explore a realistic face, panel 8202 in Tongxin Coal Mine is used as example, and 30 numerical simulation models are established by using Continuum-based Distinct Element Method software to study recovery with 4.0 m, 8.0 12.0 16.0 20.0 m 2...

For underground mining and construction, it is important to obtain a discontinuities’ model of rocks for simulations to evaluate rock stability around the working space and fluid flow in these rocks. We have developed a method using the fractal property of acoustic emission (AE) source distribution to construct a feasible crack distribution model. We confirmed the usefulness of the model throug...

Due to the increasing efforts on saving our natural environment a change in the structure of energy resources can be observed an increasing fraction of a renewable energy sources. In many countries traditional underground coal mining loses its significance but there are still countries, like Poland or Germany, in which the coal based technologies have the greatest fraction in a total energy pro...

Mining subsidence associated with longwall extractions beneath significant natural features such as rivers and streams in the Southern Coalfield of New South Wales has posed risks to the natural environment. In this paper, a case study is presented showing the methodology in two-dimensional UDEC (Itasca 2006) modeling for mining induced subsidence around river valley, taking advantage of the di...

To investigate the failure mechanisms of coal bursts in longwalls underground mines, a case study based on real burst Tangshan mine occurring 2 August 2019 was carried out to analyze cause and basic theories and, thus, propose approaches methods mitigate damage. The occurred mainly due sliding from longwall ribs simultaneous uplifting floor. As result retraction, roof above seam too stable coll...

Immediate roof caving in longwall mining is a complex dynamic process, and it is the core of numerous issues and challenges in this method. Hence, a reliable prediction of the strata behavior and its caving potential is imperative in the planning stage of a longwall project. The span of the main caving is the quantitative criterion that represents cavability. In this paper, two approaches are p...

This paper presents an unsteady coupled heat transfer model in mine air and surrounding rock mass the presence of distributed sources. The case sources is typical when analyzing temperature distribution excavations equipped with conveyor systems. For this case, asymptotic value at end excavation determined not only by exchange between but also thermal power total airflow. conclusion confirmed e...