پيش بيني نشست سطح زمين در اثر استخراج لايه هاي زغال سنگ با استفاده از توابع رياضي

Prediction of Subsidence Induced by Coal Mining Using Mathematical Functions

The concept of subsidence in mining is defined as the occurrence of differential ground surface elevation due to mining processes. Longwall mining is one of the commonly used methods in underground mining. In this paper, using mathematical modelling, two methods for subsidence prediction occurring due to coal mining are presented. Effects of parameters such as length of longwall, angle of influence and internal friction angle of roof strata have been evaluated. The results indicate that the amount of subsidence increases due to a decrease in the angle of influence and also due to an increase of parameters such as longwall length, thickness of extracting coal seams and internal friction angle. However, this increase is linearly proportional to the thickness of extracting coal seams while maintaining a nonlinear relationship with the latter parameters. The increase of subsidence with respect to increasing length of longwall has a limit, beyond which the amount of settlement remains unchanged even though the length of longwall is increased.