Vibroflotation is one type of ground improvement technique used for liquefaction mitigation in saturated sand. In order to study the feasibility of vibroflotation for liquefaction mitigation, two numerical models were created in the finite element framework. A nonlinear, coupled, hypoplastic u-p formulation was developed to simulate the behaviour of saturated sand. Numerical results were validated against on-field cone penetration test measurements after vibroflotation and centrifuge test simulating seismic site response of saturated sand. Seismic site response of saturated sand before and after vibroflotation was analysed. Saturated loose sand with fines and lower permeability underwent excess pore pressure generation, softening, and possibly liquefaction under seismic loading before vibroflotation. Sands with higher permeability were found to respond better to vibroflotation. The most effective degree of compaction was achieved in dry sands. Vibroflotation of saturated sand with fines ensured improved resistance against liquefaction whereas for coarse sands it led to complete eradication of the liquefaction.

振动浮选是用于减轻饱和砂土液化的一种地面改良技术。为了研究振动浮选法减轻液化的可行性，在有限元框架内建立了两个数值模型。开发了一种非线性耦合的增塑剂配方，以模拟饱和砂土的行为。振动浮选和模拟饱和砂土地震现场响应的离心试验后，通过现场锥体渗透试验测量验证了数值结果。分析了振动浮选前后饱和砂土的地震反应。振动浮选之前，在地震荷载作用下，具有细小和低渗透性的饱和疏松砂会产生过多的孔隙压力，软化并可能液化。发现具有较高渗透性的沙对振动浮选反应更好。在干砂中达到了最有效的压实度。对饱和砂进行振动浮选可确保提高抗液化性，而对于粗砂，则可以彻底消除液化。