减振沟在强夯施工时的减振效果研究  

Vibration-isolating effect of vibration-isolating slot in the process of dynamic compaction construction

作　　者：淳庆[1] 潘建伍[2] 

机构地区：[1]东南大学城市与建筑遗产保护教育部重点实验室,南京210096 [2]南京航空航天大学土木系,南京210016

出　　处：《振动与冲击》2010年第6期115-120,共6页Journal of Vibration and Shock

基　　金：中国博士后科学基金项目(20090450072);江苏省博士后科学基金项目(0901003c);东南大学博士后重点科研资助项目

摘　　要：为研究减振沟在降低强夯振动效应上的影响因素,首先,用ANSYS/LS-DYNA有限元软件比较了有无减振沟时的地面峰值加速度分布,分析了不同距离、不同深度、不同宽度减振沟的减振效果。结果表明:减振沟可减小60%～80%的振动加速度,减振沟的减振效果随其深度增加而增加,而减振沟的宽度基本不影响减振效果。并通过对理论数据的拟合得出了求解减振沟减振效果的近似公式。然后,结合工程实例进行了现场测试,结果表明:强夯振动持时在0.2s至0.5 s之间,峰值加速度一般出现在前0.1 s内;径向水平加速度的幅值最大,竖向加速度次之,环向水平加速度相对较小;点夯引起的最大振动通常发生在对同一夯击点的第6下夯击时,而满夯引起的最大振动发生在对同一夯击点的第2下夯击时;减振沟的减振效果达50%～90%,与理论分析结果基本一致。ANSYS/LS-DYNA was used to study the influencial factors,on the vibration-isolating effect of vibration-isolating slot under different working conditions.The distributions of peak acceleration in the cases of with and without vibration-isolating slot were compared.The vibration-isolating effects of different distance,different depth and different width of the slot were discussed.The results show that the vibration level can be reduced to 60%～80%.The vibration-isolating effect would increase with the increase of depth,but the width of slot has little influence on the vibration-isolating effect.The approximate formulas for evaluating the vibration-isolating effect of vibration-isolating slot were presented by fitting the theoretical data.The field test was then carried out.The results show that the vibration duration caused by dynamic compaction is about 0.2 seconds to 0.5 seconds and the peak acceleration appears within the first 0.1 seconds.The largest acceleration response is the radial horizontal acceleration,followed by the vertical acceleration,and the tangential horizontal acceleration is the least.The largest vibration caused by point compaction often appears at the sixth strike at the compaction point,while the largest response often appears at the second strike at the same point under full compaction.The vibration-isolating effect of vibration-isolating slot reaches 50%～90%,which is consistent with the theoretical results.

关 键 词：强夯 减振沟 振动 数值模拟 

分 类 号：TU365[建筑科学—结构工程]