Pilot Study Of Dual-band Synthetic Vibratory Compaction Method

For strengthening compaction, the author put forward method of multi-frequency composed vibrating compaction. With multi-frequency and multi-amplitude at any moment, different particles of the material are put into the resonance state and the friction between particles is weaken, which are benefit for compaction. Where double-frequency composed vibrating compaction is one of simple and efficient compaction methods, and its harmonic components should adapt to natural frequency of the material. For instance, the high frequency, fitting for compaction of topsoil, should be 36~65Hz with amplitude of 0.4~0.8mm and the low frequency, fitting for compaction of subsoil, should be 20~30Hz with amplitude of 0.8~2.0mm.The goal of parameters optimization is that the compaction degree in different depth meets requirement simultaneously with reasonable working velocity. A prototype of double-frequency composed vibrating compaction was made, and the parameters, such as frequency, rate of frequency, amplitude, rate of amplitude and phase, were optimized by orthogonal test. The results showed that phase difference and rate of frequency affected compaction degree most greatly, and amplitude and its rate did more greatly, and frequency and phase of vibration exciter lightly. And the better combination of parameters was that the low frequency should be 24Hz, rate of frequency be 1:3, amplitude be 1.0mm, rate of amplitude be 2:1, phase difference be 0 ° and phase of vibration exciter be 90° .Based on parameters optimization, results of performance experiments were that the prototype had higher compaction degree about 3.36% than ordinary rollers for topsoil, and 4.28% for subsoil and 1/3 fewer compaction times under the same compaction degree. The results revealed that the prototype, with deep-seated compaction superiority, had better compaction quality and higher productivity. Test results of different materials, such as loess and silt, indicated that the prototype had good compaction effect, for the compaction degree of top loess was 87.04% after 12 compaction times, and that of sub loess was 76.34%. Also the compaction degree of top silt was 90.25% and that of sub silt was 86.08%. Double-frequency composed...