Observation and Estimation of Long-term Performance of Preloaded and Prestressed Geosynthetic-Reinforced Soil Structure

Vertical preloading and prestressing (PLPS) of geosynthetic-reinforced soil structure aims at substantially increasing its stiffness and decreasing the residual settlement. The first prototype PLPS reinforced soil pier was constructed for a railway in 1996, and has been open to service for more than three years. Long-term measurements for more than four years have been made. It has been proven that PLPS structures are very stable for a long-term of service. The rheological characteristics such as creep and relaxation, and the residual deformation under cyclic loading of the backfill soil and reinforcement are considered to be important factors affecting the long-term behaviour of PLPS structures. The development of theoretical models of those behaviours is essential for developing the relevant design procedure of PLPS structures. In this paper, one of three-component rheology models, named “New Isotach Model”, is used to analyze the observed load-deformation behaviour of the PLPS pier during its preloading procedure.