Abstract:

The paper presents the approach to determine the influence boundary areas due to underground mining of the seams without monitoring. The case study was held at the area underground mining G9CĐ seam of Mong Duong coal mine. The fracture angles are determined from geology data of mine following Kazakowski method, afterwards they are determined based on the subsidence observation over the extracting area of I12 seam, which is located at the same mine and has the similar geology conditions with G9 seam. Comparing the angles obtained from both methods for deviation of 7.7% and mainly downstream. Using these fracture angles to determine the influence boundary area due to underground mining G9CĐ. The differences in shape and size of determining influence areas using above two methods was small, about 6.9%. Therefore, the fracture angles are determined by Kazakowski method are reliable, they can be used to determine the influence areas due to mining of the seams, which only has a plan or mining without monitoring