The Behavior of Sheet Piling Walls Supported by Struts in Soft Ground

Based on the measured field data obtained from nineteen excavation sections in Inchon International Airport project site, the horizontal displacements of the sheet piling walls with struts installed in soft ground and the lateral earth pressures acting on the these sheet piling walls were investigated. The proposed diagram of lateral earth pressure is a rectangular form, and the maximum earth pressure corresponds to . The maximum earth pressure is larger than the empirical earth pressures proposed by Terzaghi and Peck (1967) and Tschebotarioff (1973), it is similar to the empirical earth pressure proposed by NAVFAC (1982). The quantitative safe criterion of sheet piling walls with struts is established from the relationships between horizontal displacement of walls and stability number in excavated ground. If the horizontal displacement shows lower than 1% of excavation depth, the sheet piling walls exist under stable state. When the horizontal displacement is developed more than 1% and less than 2.5% of excavation depth, excavation works should be observed with caution. Also, when the horizontal displacement is developed more than 2.5% of excavation depth, appropriate remediations and reinforcements are applied to sheet piling walls.