基于S型增长模型预测隧洞开挖中上覆岩体位移

Prediction of overlying rock displacement during tunnel excavation based on "S- type growth model"

隧洞开挖爆破过程中会引起上覆岩石位移,上覆岩石位移量与时间及其距隧洞顶拱的距离存在一定的关联性。通过江苏某抽水蓄能隧洞开挖项目实际监测数据发现,不同高度处的岩石位移量与岩石距隧洞顶拱的距离(槡H)存在反比例关系,建立该比例系数与时间(ln(t))的"S型增长模型",通过该模型对后期的岩石位移进行预测。结果表明,预测结果达到很高的精度,具有一定的工程参考价值。

Displacement of overlying rock can be induced by tunnel explosive excavation, which has some relation with the time variable as well as the distance between overlying rock and tunnel ceiling. Through a monitoring case carried out in a pumped-storage power generating plant, an inverse proportion relation between displacement of rock at different levels and the distance between rock and tunnel ceiling was revealed. Furthermore, an S type growth model of the proportion coefficient and the time variable is established, by which, the rock displacement is predicted with satisfied accuracy.