关键词: 复杂地层, 盾构掘进参数, 演化规律, 有效比推力, 地层关联性

Abstract: The regularity of tunneling data is the foundation of stratigraphic perception and big data analysis during shield tunneling in composite strata. A section of Fuzhou metro passes through 16 kinds of strata such as muddy soil, clay, broken pebble, strongly weathered, and moderately weathered hard rocks. According to the characteristic of complex strata for the metro section, the effective field penetration index(EFPI) which considers the effect of chamber earth pressure is proposed, and the regularity of tunneling parameter is analyzed. The results show the following.(1) The EFPI works better than the field penetration index (FPI) in evaluating the difficulty of surrounding rock cutting by TBM and distinction of soil and strongly weathered hard rock. (2) EFPI is proportionally and linearly correlation to the strata standard penetration number, and when tunneling in the soilweathered rock strata,Log (EFPI)=2.3 can be used as the dividing standard of soil and strong weathered rock. (3）Log (EFPI) is positively correlated to Log (TPI), while Log (EFPI) is negatively correlated to the propulsion speed v. The characteristic points in soil layer are with great discreteness, while the characteristic points in the transitional section of strong to moderately weathered hard rock are with small discreteness. Function relationship among Log (EFPI), Log (TPI), Log (EFPI)and v in the transitional section of strong to moderately weathered hard rock is obtained by fitting. (4）If Log (EFPI)≤2.3, the excavation control should be focused on keeping the stability of earth pressure; if Log (EFPI)>2.3，the tunneling speed should be adjusted according to the value of EFPI to improve tunneling efficiency.

Key words: complex stratum, shield tunneling parameter, evolution regularity, effective field penetration index, stratigraphic correlation