| Popis: |
Aiming at the possible hazards that a pipe will face when crossing the goaf, preliminary analysis and assessment was given in this paper. Firstly, basic parameters in surface movement were determined using comprehensive factor P for rock character evaluation. Based on probability integral method of surface residual movement, the analysis for main section of mined-out area was completed. The results showed that the goaf had not yet been fully stable and the pipeline would be in risk of damage. Secondly, two models were introduced. One was single beam model, for the fact that the deformation of pipe and ground was out-of-sync, on the assumption that stress and deformation characteristics of pipeline above the goaf were similar to that of a beam under uniform load with at both ends fixed. The pipeline allowable subsidence value was obtained by structural mechanics method. The other was elastic foundation beam on the assumption that the deformation of pipe and ground was in sync. The pipe was regarded as an elastic foundation beam, and the allowable subsidence of pipe was obtained. At last, comparing the pipeline allowable subsidence value with value of surface residual movement, the conclusion was drawn that the pipeline would not be subjected to the hazards of mining subsidence. |
