振动与冲击
振動與遲擊
진동여충격
JOURNAL OF VIBRATION AND SHOCK
2015年
16期
73-78
,共6页
饱和土体%多排柱腔%非连续屏障%隔离效果%隔振设计
飽和土體%多排柱腔%非連續屏障%隔離效果%隔振設計
포화토체%다배주강%비련속병장%격리효과%격진설계
saturated soil%several rows of cylindrical cavities%discontinuous barrier%isolation effect%vibration isolation design
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。
假定柱腔（圓柱形空腔）長度遠大于直徑，將多排柱腔組成的非連續屏障對平麵 P1波（壓縮快波）隔離簡化成彈性波多重散射的二維平麵問題，利用複變函數保角映射法及波場勢函數展開法，據柱腔自由（土骨架軸嚮、切嚮應力為零）邊界條件穫得散射波場勢函數展開式的待定複繫數理論解。通過分析位移比值（屏障後某點由入射、散射彈性波產生的總位移與入射彈性波單獨產生的位移之比）變化規律，對比單、雙及三排柱腔屏障的隔離效果。研究錶明，邊界不透水柱腔屏障隔離效果好于透水；多排柱腔屏障對高頻入射 P1波隔離效果好于低頻入射；隨排數增多柱腔屏障隔離效果明顯提高，有效隔離區域明顯增大；噹排數達到三排時柱腔屏障後一定範圍內隔離效果達70％，效果較理想。
가정주강（원주형공강）장도원대우직경，장다배주강조성적비련속병장대평면 P1파（압축쾌파）격리간화성탄성파다중산사적이유평면문제，이용복변함수보각영사법급파장세함수전개법，거주강자유（토골가축향、절향응력위령）변계조건획득산사파장세함수전개식적대정복계수이론해。통과분석위이비치（병장후모점유입사、산사탄성파산생적총위이여입사탄성파단독산생적위이지비）변화규률，대비단、쌍급삼배주강병장적격리효과。연구표명，변계불투수주강병장격리효과호우투수；다배주강병장대고빈입사 P1파격리효과호우저빈입사；수배수증다주강병장격리효과명현제고，유효격리구역명현증대；당배수체도삼배시주강병장후일정범위내격리효과체70％，효과교이상。
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 P1 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%.
