Monitoring Of Subsidence Movements at Major Infrastructure

Time based mine subsidence predictions provide a valuable tool, as part of an overall management strategy to protect infrastructure, which involves making subsidence predictions at set increments of longwall travel. The predictions can be presented as a series of subsidence contours or profiles, and can be animated to show the progression of the subsidence travelling wave. The observed movements at major items of infrastructure can then be compared to the predicted movements at any time throughout the mining period. The challenges in providing time based predictions are discussed. Two examples are provided: the Main Southern Railway at Tahmoor Colliery and the gas and water pipelines across an unnamed Creek at West Cliff Colliery. Both examples show that time based predictions can provide a useful tool as part of an overall management strategy where major items of infrastructure are mined beneath. Time based predictions can be readily provided for any major item of infrastructure using current methods of subsidence prediction.