Research on the Effect of the Mine Waste Dump on the Stability of Tunnels Below in the Quangninh Coal Area by Numecical Method

Abstract

Nowadays, there are many underground coal mines in Quang Ninh, Vietnam have been exploiting coal seams below the mine waste dump such as Khe Cham II, Mong Duong, Mao Khe, and Ha Lam… Coal Company. Many mine waste dumps have reached the height of dumping from 400m, especially up to over 400m. The rock mass pressure due to the weight of the rock mass in the mine waste dump is considered an artificial pressure formed from the process of dumping soil and rock, it will be part of the pressure acting on the furnace lines located under the mine waste dump. The paper presents the current status of the mine waste dump and the coal seams that have been and will be exploited located below the mining waste dump in Cam Pha Quang Ninh and based on the actual conditions of the Bang Nau, Khe Cham II coal mine waste dump. The studies used the 2D FEM RS2 program to create simulation models with the mine waste dump to study the primary stress distribution in the rock mass. The objective of this study is to highlight the influence of the relationship location of tunnels below with the inclined coal/rock mass layer on the rock support behavior of the underground tunnels in the Quang Ninh coal area. The simulation results will help the consulting and construction companies to calculate the rock pressure acting on the tunnels located under the mining waste dump.