Abstract: The stateofthe art of the effect of cyclic loading frequency on the change of the dynamic pore water pressure as well as the cumulative plastic strain is reviewed and studied in this paper. The true static and cyclic triaxial test equipment SPAX200 made by GCTS was used to study the performance of the saturated peaty soft clay. The effect of traffic loading on the pore water pressure and the cumulative plastic strain in the sample was investigated. The test results indicate that, the lower the cyclic load frequency, the larger the total dynamic pore pressure value and the cumulative plastic strain in the soil sample. When the loading frequency is lower than 0.1 Hz, larger influence of loading frequency on the rate of the pore pressure and plastic strain increase. When the loading frequency is greater than 0.5 Hz, the loading frequency has negligible influence. Under the high cyclic stress level, the number of cyclic loading has a large impact on the dynamic pore water pressure and the cumulative plastic strain. However, the influence of the cyclic loading number is minimal when the cyclic stress level is low.

Key words: Saturated Soft Cohesive Soils, Low Frequency, Traffic Loads, Pore Water Pressure, Cumulative Plastic Strain, Number of Cycles