Preliminary study on determination of reasonable ratio of spacing to diameter of double tunnels under earthquake

DOI

10.2991/iceesd-17.2017.1How to use a DOI?

Keywords

earthquake; reasonable ratio of spacing to diameter; double tunnels; relative displacement; plastic zone

Abstract

For determining the reasonable ratio of spacing to diameter of double tunnels, the criterion is often only for the excavation, and does not take into account the earthquake situation. In order to ensure the stability of surrounding rock masses, safety and economic rationality during construction and operation of the adjacent tunnels, in this paper, the dynamic responses with different spacing under different earthquake actions and different constitutive relations are analyzed. Based on the plastic zone of the inter-tunnel rock mass connecting or not and the inflection point of the relative displacement curve of the key points of the surrounding rock mass of the tunnel, the reasonable ratio of spacing to diameter under earthquake action is preliminarily determined. The results show that the influence of the earthquake on single tunnel is smaller than that on double tunnels, regardless of the distance between the tunnels and the diameter of the tunnel. Under earthquake, the closer the double tunnels are, the relative displacement is larger. When the distance is smaller than the tunnel diameter, the relative deformation is much larger than other cases, when the distance is 2-3 times diameter, the relative deformation is basically maintained at a stable value. For different diameter of tunnels, the reasonable spacing is not the same under excavation, but its reasonable ratio of spacing to diameter is about 1.5, more than 1.5, the plastic zone of the surrounding rock between tunnels will not penetrate. The response trend of the surrounding rock is the same under excavation and earthquake, having nothing to do with the diameter, and its reasonable ratio of spacing to diameter is about between 2 and 3. Compared the reasonable ratio of spacing to diameter under excavation, the reasonable ratio of spacing to diameter under the action of the earthquake is larger, so it needs to determine the reasonable ratio of spacing to diameter in high seismic intensity areas, not only consider excavation, but also consider earthquake. It is hoped that the research can provide some technical reference for practical engineering

Copyright

© 2017, the Authors. Published by Atlantis Press.

Open Access

This is an open access article distributed under the CC BY-NC license (http://creativecommons.org/licenses/by-nc/4.0/).

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TY  - CONF
AU  - Yongqiang Zhou
AU  - Qian Sheng
AU  - Xianlun Leng
AU  - Xiaodong Fu
AU  - Nana Li
PY  - 2017/04
DA  - 2017/04
TI  - Preliminary study on determination of reasonable ratio of spacing to diameter of double tunnels under earthquake
BT  - Proceedings of the 2017 6th International Conference on Energy, Environment and Sustainable Development (ICEESD 2017)
PB  - Atlantis Press
SP  - 1
EP  - 8
SN  - 2352-5401
UR  - https://doi.org/10.2991/iceesd-17.2017.1
DO  - 10.2991/iceesd-17.2017.1
ID  - Zhou2017/04
ER  -