| As part of a highway relocation project (RT44) in Carver Massachusetts, long sheet pile walls were installed in Cranbury bogs and ponds in order to mitigate environmental concerns. The subsurface consisting of deep peat deposits challenges the current understanding of the pressures developing on sheet piles and the parameters used for its design. A large instrumentation program has been conducted over a period of 2.5 years, measuring the peat pressure developing along the sheet pile walls during construction and service. This project includes (i) original wall design and associated assumptions, (ii) a detailed field and laboratory study investigating the vertical and lateral properties of the peat, (iii) the instrumentation of the walls using inclinometers and vibrating wire total pressure cells along with a new thin film tactile pressure sensors, (iv) the measurements of the pressures and deflections developing along the wall and independent surveying over various stages of construction including excavation, fill, deep dynamic compaction (DDC) and MSE wall construction, (v) the modeling of the wall-soil interaction during the aforementioned stages using the FEM code PLAXIS, (vi) comparisons between the modeling results and measured values at the different stages, and (vii) the development of recommended parameters for future design of walls in peat. |
