摘要
假定柱腔(圆柱形空腔)长度远大于直径,将多排柱腔组成的非连续屏障对平面P1波(压缩快波)隔离简化成弹性波多重散射的二维平面问题,利用复变函数保角映射法及波场势函数展开法,据柱腔自由(土骨架轴向、切向应力为零)边界条件获得散射波场势函数展开式的待定复系数理论解。通过分析位移比值(屏障后某点由入射、散射弹性波产生的总位移与入射弹性波单独产生的位移之比)变化规律,对比单、双及三排柱腔屏障的隔离效果。研究表明,边界不透水柱腔屏障隔离效果好于透水;多排柱腔屏障对高频入射P1波隔离效果好于低频入射;随排数增多柱腔屏障隔离效果明显提高,有效隔离区域明显增大;当排数达到三排时柱腔屏障后一定范围内隔离效果达70%,效果较理想。
The lengths of cylindrical cavities were considered as much larger than their diameters, so the isolation of incident plane P1 waves （ fast compressive wave ） by discontinuous barriers composed of several rows of cylindrical cavities was simplified as a two-dimensional plane problem. The conformal mapping method of complex functions and expansion method of wave functions were adopted, the cylindrical cavities were considered to be of free boundaries, where no stresses exist, and then the theoretical solutions about the complex coefficients of scattering wave potential functions were obtained. By studying the normalized displacement amplitudes, which are expressed as the ratios of displacement amplitudes of soils behind the barriers caused by both the incident and scattering waves to those only by the incident P~ waves, the isolation effects of the barriers composed of one, two and three rows of cylindrical cavities were compared. The results reveal that the isolation effects of barriers composed of several waterproof cylindrical cavities are better than those composed of permeable cylindrical cavities ; the isolation effects of barriers composed of several rows of cylindrical cavities on incident P1 waves with higher frequencies are much better than on those with lower frequencies; with the increasing of row number of cylindrical cavities, the vibration isolation effects is obviously improved, and the effective isolation area is obviously increased; as the row number of cylindrical cavities reaches three, the isolation effects at some locations behind the barriers are much better and almost increase to 70%.
出处
《振动与冲击》
EI
CSCD
北大核心
2015年第16期73-78,共6页
Journal of Vibration and Shock
基金
国家自然科学基金项目(51008286
51278467)
河南省高校科技创新人才支持计划(14HASTIT050)
关键词
饱和土体
多排柱腔
非连续屏障
隔离效果
隔振设计
saturated soil
several rows of cylindrical cavities
discontinuous barrier
isolation effect
vibration isolation design
