Consolidation properties for vertical drain under complicated loads and nonlinear well resistance

Based on the experience of Zhejiang coastal beach reclamation projects, consolidation for vertical drain is considered in the calculation of the non-linear well resistance over time in soft foundation treatment. Based on the equal strain assumption and non-linear well resistance over time, the analytical solution for vertical drain is derived under the multistep linear loads and cyclic loads. The correctness of the present theory is verified by comparing with the existing theory of TANG X W, etc. (2000), Zhu et al. (2004) under constant well resistance. According to this paper, the longer the time of linear load, the slower the calculation rate of the foundation with vertical drain, and the more significant the difference with the constant load conditions. At the same time, the permeability coefficient of vertical drain with time decays faster, and the consolidation speed is slower. Under the cyclic loading, ground consolidation rate is generally between the maximum load and the minimum load, and the degree of consolidation is shocking with the external load. The permeability of vertical drain decays faster, and the consolidation degree rebounds more obviously. Ultimately the shock tends to stable.