Wireless remote spatiotemporal monitoring of high-fill foundation deformation

The spatial and temporal deformation patterns and deformation control indicators of high-fill foundations directly affect the design, construction and operational safety of high-fill projects. In situ monitoring can comprehensively reflect the deformation of high-fill during and after construction. In this paper, we have first designed and installed an integrated wireless remote monitoring system for high-fill to achieve real-time dynamic monitoring of settlement, pore water pressure and soil pressure of the fill foundation. Based on the monitoring results of nearly one year of the construction period and two years after construction, it was found that the deformation amount and deformation rate of the high-fill foundation showed a non-linear growth relationship with the filling rate and filling height. The settlement deformation of the high-fill foundation during the loading period was mainly dominated by the original foundation soil, accounting for 54.4% of the total settlement on average; the settlement deformation during the post-construction period was mainly dominated by the filling body, accounting for 77.04% of the total settlement on average, and the settlement deformation during the post-construction period mainly occurred in the first year after construction. The analysis of the deformation mechanism suggests that the deformation of the filling body is dominated by exhaust consolidation during the loading period and drainage consolidation during the post-construction period; the deformation of the original foundation soil is dominated by drainage consolidation during the loading period and drainage consolidation develops slowly during the post-construction period. It is recommended that the original foundation should be reinforced before the large area filling construction, and that the filling rate should be strictly controlled during construction. The research results can provide a scientific basis for deformation calculation and stability assessment of high-fill foundations.