Sentence examples for of roof stability from inspiring English sources
The performance function of roof stability is proposed and is adopted for reliability analysis and design.
Arching effect has been attributed as a factor of roof stability of underground rock excavations, which affects excavation geometry and rock support.
Under the combined effects of the above two conditions, a novel and comprehensive failure mechanism is postulated for analyses of roof stability of tunnels.
It is found that the height of the inner boundary of the arching area is an indicator of the roof stability of underground excavations.
In underground coal mines, the tunnel surrounding rock conditions changed greatly, roof litho logy even happened thinning and disappearing within the range of tens of meters, so that roof stability changed.
We subsequently designed a proper range of URD, developed a testing method of URD with the function of mining protection, evaluated roof stability through analyzing the test data and then determined a reasonable URD.
Considering the factors of the geological conditions, the immediate roof stability and the efficiency of the labor arrangement system, the URD of the advancing roadway of 9802 working face in Zhangshuanglou coal mine was determined to be 6 m using the proposed method.
It was based on the familiar principle of the bicycle wheel; its roof had a diameter of 100 metres (330 feet), with a steel tension ring at the perimeter from which two layers of radial cables were tightly stretched to a small tension ring in the middle the double layer of cables gave the roof stability against vertical movement.
The results are then used to assess the roof stability of cavities adjacent to upper bench blasting.
The results show that the initial stress state (H and k0) has more significant effects on the roof stability of underground rock caverns than the GSI and cavern geometry (h/B).
It is widely accepted that the fully grouted rockbolts provide better roof stability in areas of very poor roof condition which may be caused by high ground stress conditions.
