Railway subgrades are always subjected to cyclic loading with intermittent rest periods. When railways are built on low permeable soft estuarine clays, excess porewater pressures (EPWP) can accumulate and reach critical levels under prolonged loading conditions. Although numerous studies have been conducted on the clay subgrade under continuous cyclic loading, the behaviour during the rest period has not been studied to a greater extent. Large-scale cyclic consolidation tests conducted in the laboratory, considering two-way drainage, suggest that accumulated EPWP during cyclic loading redistributes during the rest period. Therefore, when adequate rest periods with proper drainage are present, the occurrence of EPWP reaching critical levels can be avoided. This paper presents an analytical model that can predict EPWP accumulation and dissipation. The proposed model is validated using the results of large-scale cyclic consolidation tests.