关键词: 低幅值, 高循环, 应变累积, 累积模型

Abstract: High-speed railway track and nearby structures are subjected to low-amplitude and high-cycle loading. Additional settlements of track and structures may be caused by irreversible strain accumulation of soils under the low-amplitude and high-cycle loading. At present, the theories described the deformation characteristics of soils have two kinds, stress-strain hysteretic model based on classical plastic theory, e.g. bounding surface model, and strain accumulation model based on empirical law obtained from the cyclic triaxial tests, e.g. Bochum accumulation model. Based on the existing test studies and classical elastoplastic theory, a strain accumulation model is proposed to predict strain accumulation behavior of soils subjected to low-amplitude and high-cycle loading. The model describes the accumulation law of plastic volume strain via a logarithmic law; and it can measure the strain accumulation. The direction of strain accumulation is determined using the flow rule of the modified Cam-clay model. Finally, with the simulation of test data, it is shown that the proposed model can predict strain accumulation behavior of soils subjected to low-amplitude and high-cycle loading. It has widely application prospect.

Key words: low-amplitude, high-cycle, strain accumulation, accumulation model