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Abstract When conducting numerical analysis of plastic cracking zone of rock mass subjected to underground excavation，its results mainly depend on the adopted plastic flow criterion. Therefore，the discrepancy between numerical results and practical engineering is often considerable. The criterion for excavation disturbed zone(EDZ) is still not clear and only empirical，and the acoustic emission(AE) also lacks efficiency and accuracy in engineering practices. Based on the analysis of major influencing factors and a review of several experiments，the mathematical model for determining EDZ of underground caverns is put forward. The proposed model is based on analyzing AE data derived from construction process and statistical treatments. According to the abundant data，the underlying laws of EDZ development are analyzed by data mining. Some new concepts，such as major disturbed zone and percentage of spreading disturbed zone，are proposed by analyzing temporal and spatial characteristics of monitored displacements. The proposed method provides a new approach for determining general stability and disturbed degree of surrounding rock in underground caverns. Also，it provides an effective approach for analyzing monitoring data and assessing excavation quality of underground caverns. It can be referenced by other similar projects as well.
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Received: 10 August 2009
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