With the help of similar material simulation test,time series system for induced caving of roof in continuous mining under complex backfill in ore body No.92 of Tongkeng Tin Mine was studied. According to the similari...With the help of similar material simulation test,time series system for induced caving of roof in continuous mining under complex backfill in ore body No.92 of Tongkeng Tin Mine was studied. According to the similarity theory,a two-dimensional similar simulation test-bed was constructed. The stress and displacement that change along with the advance of mining were acquired and analyzed automatically by data system. The processes of continuous mining of ore-block in 5 intervals and artificial induced caving of roof were simulated. The results of the test show that ore body remained as safety roof in thickness of 15 m guarantees the safe advance of stoping work face. Caving of safety roof puts in practice at the first two mining intervals when the third interval of continuous mining is finished,and one interval as the safety distance should be kept all the time between stopping and caving. While mining in the last interval,pre-slotting should be implemented first of all,and the roof of the last two mining intervals is caved simultaneously. Only this kind of time series system can be an efficient and safe way for induced caving of roof in continuous mining.展开更多
A new numerical model is presented to simulate fracture initiation and propagation in geological structures. This model is based on the recent amalgamation of established failure and fracture mechanics theory, which h...A new numerical model is presented to simulate fracture initiation and propagation in geological structures. This model is based on the recent amalgamation of established failure and fracture mechanics theory, which has been implemented to the finite difference FLAC code as a constitutive FISH userdefined-model. Validation of the model has been studied on the basis of comparing the transitional failure modes in rock. It is shown that the model is capable of accurately simulating fracture distributions over entire brittle to ductile rock phases. The application of the model during longwall retreat simulation highlighted several caving characteristics relevant to varying geological condition. The distribution and behaviour of modelled fractures were both realistic and shown to provide an enhanced post failure analysis to geological structures in FLAC. Moreover, the model introduces new potential insight towards the failure analysis of more complicated problems. This is best suited towards improving safety and efficiency in mines through the prediction of various key fractures and caving characteristics of geological structures.展开更多
基金Project(50490274) supported by the National Natural Science Foundation of ChinaProject(20050533035) supported by the Specialized Research Fund for the Doctoral Program of Higher Education of ChinaProject(1343-77236) supported by the Doctor Degree Paper Innovation Engineering of Central South University, China
文摘With the help of similar material simulation test,time series system for induced caving of roof in continuous mining under complex backfill in ore body No.92 of Tongkeng Tin Mine was studied. According to the similarity theory,a two-dimensional similar simulation test-bed was constructed. The stress and displacement that change along with the advance of mining were acquired and analyzed automatically by data system. The processes of continuous mining of ore-block in 5 intervals and artificial induced caving of roof were simulated. The results of the test show that ore body remained as safety roof in thickness of 15 m guarantees the safe advance of stoping work face. Caving of safety roof puts in practice at the first two mining intervals when the third interval of continuous mining is finished,and one interval as the safety distance should be kept all the time between stopping and caving. While mining in the last interval,pre-slotting should be implemented first of all,and the roof of the last two mining intervals is caved simultaneously. Only this kind of time series system can be an efficient and safe way for induced caving of roof in continuous mining.
文摘A new numerical model is presented to simulate fracture initiation and propagation in geological structures. This model is based on the recent amalgamation of established failure and fracture mechanics theory, which has been implemented to the finite difference FLAC code as a constitutive FISH userdefined-model. Validation of the model has been studied on the basis of comparing the transitional failure modes in rock. It is shown that the model is capable of accurately simulating fracture distributions over entire brittle to ductile rock phases. The application of the model during longwall retreat simulation highlighted several caving characteristics relevant to varying geological condition. The distribution and behaviour of modelled fractures were both realistic and shown to provide an enhanced post failure analysis to geological structures in FLAC. Moreover, the model introduces new potential insight towards the failure analysis of more complicated problems. This is best suited towards improving safety and efficiency in mines through the prediction of various key fractures and caving characteristics of geological structures.