The 4th International Symposium on Mine Safety Science and Engineering (ISMSSE2018)

287 / 2018-04-28 11:27:14

Analysis of goaf collapse disaster based on heavy ball landing experiment

goaf collapse, vibration speed, heavy ball landing tests, vibration monitoring, Protodyakonov's arch

Mine Dynamics Disaster > goaf

In order to reveal the vibration laws of goaf collapse, the simulation experiments of goaf collapse were carried out by the heavy ball landing tests from different heights. The heavy ball weight was 4 kg and the heights were 1.0 m, 1.5 m and 2.0 m respectively. The vibration monitoring points were arranged at distances of 1m, 2m, 3m and 4 m respectively to study the law of vibration velocity with distance, which provide guidance for the prediction of goaf collapse. The results showed that the energy of the heavy ball has a positive correlation with the vibration speed. The greater the weight and the height, the greater the energy of heavy ball, and the greater the vibration disaster. With the increase of the measuring distance, the vibration speed shows an overall trend of attenuation. Based on the theory of Protodyakonov's arch, the calculation model of goaf collapse was established. The analysis results show that the goaf collapse is related to the span, length, collapse height, rock properties, etc. The larger the span and length, the higher the collapse height, the worse the rock mass condition, the greater the vibration disasters. The goaf size must be strictly controlled to reduce the safety risks. The goaf hidden dangers could be eliminated through the method of filling or roof caving.