Field testing and numerical analysis on performance of anchored sheet pile quay wall with separate pile-supported platform

Abstract

The anchored sheet pile quay wall with a separate pile-supported platform was invented to meet the functional and serviceable requirements of engineering practice, including the higher elevation of retained soils and smaller wall deflection, based on the conventional anchored sheet pile structure. This paper presents the field testing as well as the three-dimensional numerical analysis on the first practical case of the new structure. The performance of the structure and soil is described and discussed, including the lateral deflection, bending moment, axial force, tensile force, and lateral earth pressure. The measured data and computed results show that the lateral deflection of the sheet pile wall can be significantly reduced, and the measured maximum lateral displacement is approximately 0.21% of the wall height in this case. The bending moment and axial force of the supporting piles are generally greater than those of the sheet pile and anchor wall, indicating that the pile-supported platform is efficient for reducing the loads acting on a sheet pile. The effects of the pile-supported platform can be summarized as a combination of blocking effect of the supporting piles to carry the lateral earth pressures as well as a load-relieving effect of the platform to transfer the vertical loads to deeper foundation soils through the pile. Compared to the numerical results, Coulomb's earth pressure theory significantly overestimates the earth pressure loads acting on the sheet pile at higher elevations. Furthermore, the dredging activity has greater effects on the behaviours of the sheet pile wall and front-pile than the superstructure construction.