Subsidence Management System for Underground Mining

Abstract

Potash mining is an important economic activity in the northeast of Spain. However, one of the main environmental issues produced for such type of mining is subsidence, which generates horizontal and vertical ground displacements. A Geographic Information System (GIS)-based model is proposed as a management system in a case study with two mines. This system is able to deal with subsidence data and its behavior over time. More than 1300 control points are included in the GIS, with data since 2007. These data processed by the GIS allowed determining the module, sense and direction of the displacements, the sinking velocity and the possible affectation of subsidence to infrastructures and buildings. Hence, the system created can be a useful tool to manage subsidence data, determine its evolution, predict future environmental and social impacts and control corrective measures.

Application of Transient Electromagnetic Method for Investigating the Water-Enriched Mined-Out Area

“…Because in these area, the induced electromagnetic field values distributed in this area can be considered as uniform [33]. Different fundamental frequencies have different observation time [14,32]. In general, the lower frequency, the longer observation time, but with lower efficiency.…”

“…Mined-out areas can be water filled, when water inrushes or surface water leaks through cracks into excavated areas, surface damage that is caused by subsequent subsidence might appear [11]. A typical collapsed area can be divided into three zones, such as Caving zone, Fault zone, and crooked zone, as shown in Figure 1 [11][12][13][14].…”

Finite Element Analysis of the State of Stresses on the Structures of Buildings Influenced by Underground Mining of Hard Coal Seams in the Jiu Valley Basin (Romania)

“…The prognosis and the study of the deformations of the lands affected by the underground mining can be done with the aid of empirical methods (profile functions and influence functions); physical models (based on rock like or optically active materials); analytical models (plate and beam theory [7], etc. )); and numerical models (finite element, finite difference, boundary element, and distinct element methods [19][20][21]).…”

“…The correlation between the values of the deformations and the damage caused to the buildings is established by Wardell [42] in five classes, in which the severity of the damage caused to the buildings is assessed according to their length and the deformation to the foundations. Later, other experts detailed this classification into six classes for two-storey brick structures, taking into consideration deflection ratios, extensions, and crack width [21,43,44].…”

“…These constraints have created special problems, both in terms of model construction and calculations. Therefore, the closest numerical models known in the literature are those relating to buildings under the influence of tunnels (excavations with a small volume of the order of thousands of m 3 ), which involve models with much smaller dimensions (with a volume of the order of hundreds of thousands of m 3 ) and implicitly require less important computing resources [20][21][22][23][24][25][26][27][28][29][30]. Therefore, this numerical modelling analysis, which is specific to civil engineering, has allowed consideration of many details regarding the construction of models and constitutive laws applied to rocks and materials, which are much more complex than in the case of mining engineering problems (as they are treated in this article).…”