隧洞工程适宜埋藏深度的探讨

在隧洞工程设计中,由于受到塌落拱理论的影响,大都认为只要隧洞埋藏深度不小于规范规定的最小围岩厚度即可,而没有一个明确的适宜埋藏深度的概念,针对这一现象,本文由连续介质力学模型出发,以现行《水工隧洞设计规范》所建议的计算洞挖后需要支护提供抗力的方法为基础,首先分析了隧洞埋藏深度对围岩应力场和稳定性的影响,接着总结提出了隧洞工程适宜埋藏深度的概念及其确定的原则和方法。此外,还对水工隧洞设计规范附录八中,确定需要控制的塑性区深度的方法,提出了我们的改进建议。

The Discussion on the Reasonable Burying Depth for the Tunnels

This paper analysed that different cover thick of rock mass influence stress field and stability of surrounding rock for underground chamber. The concept of the reasonable burying depth for the tunnels was summarized and was put forward. At the same time, principle and method of the deciding reasonable burying depth for the tunnels were suggested as well. Furthermore we proposed improving opinion on the method of deciding demand controlled plastic range D in design code for hydraulic tunnels.