Numerical evaluation on cutoff behavior of retaining structures on seepage

摘要

A three-dimensional finite element model is established to analyze the cutoff behavior ofretaining structures on groundwater seepage and settlement induced by dewatering. The cutoff behavior isinfluenced by many factors, such as penetration depths of retaining structures, and hydraulic characteristics ofaquifers. Results show that both drawdown of groundwater level and settlement outside of the excavated pitdecrease with the increase of the relative insertion depth of retaining structures in Aquifer I (AqI). Variationsof groundwater level (Δh) and settlement (s) increase with the increase of hydraulic conductivities of AqI,whereas Δh decreases with the increase of specific storage of Aquitard I (AdI). In case of AqI with lowpermeability, it is acceptable that retaining structures has a relative insertion depth larger than 70%. However,retaining structures should penetrate into AdI when AqI has a permeability greater than 1 m/d.