Aiming at the characteristics of the poor steady ability, the short stable time and severe deformation behavior of weakly cemented soft surrounding rock around extraction roadway, a bolt–cable combined supporting tec...Aiming at the characteristics of the poor steady ability, the short stable time and severe deformation behavior of weakly cemented soft surrounding rock around extraction roadway, a bolt–cable combined supporting technology was proposed. Numerical simulation was performed by using FLAC3 D software to study the effects of different supporting systems. The simulation result proves that those supporting systems have good practical values. Based on real-time monitoring and analysis of the deformation of surrounding rock and the stress of supporting structure, real time information of deformation of surrounding rock and stress state of supporting structure of extraction roadway within weakly cemented strata was obtained. Monitoring results show that large deformation and failure of surrounding rock of extraction roadway within weakly cemented strata can be effectively controlled by the bolt–cable combined supporting technology, which ensures the long-term stability and safety of surrounding rock and supporting structure.展开更多
The mining area deformation monitoring theory and method using precise point positioning (PPP) ambi- guity resolution (AR) were studied, and an ambiguity fixing model with satellite and receiver combina- tion phas...The mining area deformation monitoring theory and method using precise point positioning (PPP) ambi- guity resolution (AR) were studied, and an ambiguity fixing model with satellite and receiver combina- tion phase delay (CPD) was proposed for zero-differenced PPP ambiguity fixing and its corresponding formula derivation was given. The data processing results for I h at six IGS stations in China show that 93% of ambiguities can be fixed within 10 min and all ambiguities can be fixed within 15 min. After ambi- guity fixing, the positioning accuracy is improved by more than 85% in the E and N directions, with abso- lute positioning accuracy reaching millimeter level, and it was improved by 70% in the U direction, reaching centimeter level; the proposed zero-differenced ambiguity fixing model can effectively improve the convergence rate and positioning accuracy in PPP. Data monitoring continuously conducted for half a year at four COPS stations of Shanxi China Coal Pingshuo Group validated the feasibility of using PPP in mining area deformation monitoring.展开更多
基金financially supported by the National Natural Science Foundation of China (Nos. 51174196, 51204168, 51109209 and 51309222)the Youth Fund Project of Jiangsu Province Natural Science Foundation (No. BK20130193)
文摘Aiming at the characteristics of the poor steady ability, the short stable time and severe deformation behavior of weakly cemented soft surrounding rock around extraction roadway, a bolt–cable combined supporting technology was proposed. Numerical simulation was performed by using FLAC3 D software to study the effects of different supporting systems. The simulation result proves that those supporting systems have good practical values. Based on real-time monitoring and analysis of the deformation of surrounding rock and the stress of supporting structure, real time information of deformation of surrounding rock and stress state of supporting structure of extraction roadway within weakly cemented strata was obtained. Monitoring results show that large deformation and failure of surrounding rock of extraction roadway within weakly cemented strata can be effectively controlled by the bolt–cable combined supporting technology, which ensures the long-term stability and safety of surrounding rock and supporting structure.
基金Financial support from the National Natural Science Foundation of China (No. 41074010)the Jiangsu Innovation Works Fund of Postgraduate (No. CXZZ11-0299)the Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)
文摘The mining area deformation monitoring theory and method using precise point positioning (PPP) ambi- guity resolution (AR) were studied, and an ambiguity fixing model with satellite and receiver combina- tion phase delay (CPD) was proposed for zero-differenced PPP ambiguity fixing and its corresponding formula derivation was given. The data processing results for I h at six IGS stations in China show that 93% of ambiguities can be fixed within 10 min and all ambiguities can be fixed within 15 min. After ambi- guity fixing, the positioning accuracy is improved by more than 85% in the E and N directions, with abso- lute positioning accuracy reaching millimeter level, and it was improved by 70% in the U direction, reaching centimeter level; the proposed zero-differenced ambiguity fixing model can effectively improve the convergence rate and positioning accuracy in PPP. Data monitoring continuously conducted for half a year at four COPS stations of Shanxi China Coal Pingshuo Group validated the feasibility of using PPP in mining area deformation monitoring.