Study on Safety of Anchored Discontinuous Jointed Rock-mass Stability in Hydropower Energy Development

摘要

In order to alleviate severe energy problems increasingly, large hydropower energy development project are constructed in our country. For underground engineering in these project, the existence of jointed rock mass will endanger the safety of project. Present numerical simulation of anchored discontinuous jointed rock-mass can not pertinently reflect the actual anchorage effects. This paper establishes complex calculation model in line with the actual condition: an entity element is used to simulate an anchor and a contact element is applied between the boll and the rock-mass. The stress intensity factor at the wing crack tip is used as the basis for evaluating the stability and the calculated results are compared with the results produced by the virtual spring model (the calculation model which enables the anchor to be equivalent with the virtual spring). The crack-propagation prevention capacity of the entity element with bending degree of freedom is obviously better than that of the virtual spring anchor which only has tension and compression degree of freedom. The calculated results reveal the disadvantage of virtual spring model which is widely applied in engineering and more practical and effective method is brought forward. The conclusion can be offer reference to design and construction of similar engineering.