高铁路基减振结构三维复频散曲线计算分析OA

To address the limitation of existing two-dimensional complex dispersion curves in fully reflecting the attenuation degree of periodic pile rows on elastic waves,a method for calculating three-dimensional complex dispersion curves of periodic pile rows was established using the PDE module in the finite element software COMSOL.This method accounted for the mixed propagation of compressional waves,shear waves,and surface waves,and enabled quantification of the attenuation level at each frequency within the attenuation zone for infinite periodic pile rows.The influence of different pile arrangements,pile lengths,and pile materials on the characteristics of the complex dispersion curves was analyzed,and the results were validated through frequency-domain responses from finite periodic pile row models.The results show that:the triangular arrangement exhibits the highest peak attenuation frequency(32.5 Hz)and the widest attenuation bandwidth(26.0-37.6 Hz),which is closest to the dominant vibration frequency of high-speed trains.Increasing pile length slightly reduces the attenuation bandwidth but has minimal effect on the peak frequency.Steel piles provide better attenuation performance than concrete piles and rubber-steel composite piles;notably,the composite pile effectively suppresses low-frequency vibrations due to its local resonance characteristics.Numerical simulations of finite periodic pile rows indicate that setting four rows of piles achieves good attenuation performance,with the attenuation zone and magnitude closely matching the predictions from the complex dispersion curve calculations.