Dual-band Synthetic Vibratory Compactor Dynamics Simulation Study

In order to strengthen compaction process, the method of multi-frequency composed vibrating compaction was put forward in this paper, in which multi-frequency and the corresponding amplitude were performed simultaneously on the material at any moment to made different particles of the material at resonance state. And taking a example of double-frequency composed vibration compaction, the theoretical analysis, experiment and dynamical simulation were carried on in the paper.The influence of the composition of frequency and amplitude on the composed vibration was analyzed in theoretically. The ratio of the two frequencies should be rational number. the high frequency value was suggested to be 36~65Hz, and the low frequency value was suggested to be 20~30Hz. The initial phase difference of thetwo frequencies should be φ=π/2(1-λ) or φ=3π/2(1-λ). The nominal amplitudeof the high frequency and the low frequency should both be lower than the amplitude of single frequency vibration. It was suggested to adopt 0.8~ 1.6mm as the low frequency nominal amplitude, and 0.4~0.6mm as the high one.A prototype of double-frequency composed vibratory roller was designed and manufactured, and several experiments for optimizing parameters, contrasting different vibratory modes and testing the applicability to different materials were carried out. The optimizing experiments showed that when compacting graded soil the optimized parameters should be as the followings: 24Hz for the low frequency, 1:3 for frequency ratio, 1.0mm for the low frequency amplitude, 2:1 for the amplitude ratio, 0° for the initial phase difference of the two frequencies and 90° for the initial phase difference of the vibration exciter. The contrasting experiments indicate that, it was 3.36% higher than normal single frequency roller with the similar standard in compaction degree for the topsoil, 4.28% higher in compaction degree for the subsoil, and the compaction times was reduced 1/3 to reached the same compaction degree. The applicability experiments revealed that, the topsoil compaction degree for loess was 87.04%, the subsoil compaction degree was 76.34% and it was 90.25% for top silt compaction, and 86.08% for sub silt.A dynamic model had been established which was able basically to reflected the compacting process. The dynamic identification of the soil parameters, dynamic...