摘要

Planning and constructing tunnels in urban or ecologically sensitive areas require an environmentally friendly approach. However, it is quite difficult to characterize, assess, and predict the environmental consequences of tunneling, especially in carbonate mountain areas. It is found that there is an Epi-Fissure-Karst-Zone (EFKZ) in Laoshan carbonate mountain, which is situated in middle China. EFKZ is a zone intensively fractured, weathered, karstified; it is thereby permeable and of a vital ecological significance. Monitoring results in boreholes indicate that tunneling has the potential to cause noticeable drawdown of groundwater level in the EFKZ, which means a decrease of groundwater retention capacity. Based on monitoring results and comprehensive analysis, this paper studies the influencing factors of tunnel construction on the groundwater in the EFKZ as a first-step research, and then puts forward a TEIF parametric methodology for assessment of potential impacts of tunneling on groundwater in the EFKZ and ecological conditions. Applying the TEIF parametric method, a risk assessment of environmental impact of tunneling has been made for Laoshan Tunnel.

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