影响强夯地面振动衰减的因素分析

夯击能量和地基土体特性是影响强夯地面振动衰减的两个重要因素。观测和分析表明 ,夯击能量越大 ,地面振动衰减越快。在较小的夯检距上 ,强夯地面振动的强度对夯击能量的变化相对较敏感 ,表现为在近距离上地面振动强度随夯击能量增加的速率较大。地面振动随距离的负指数幂衰减公式中当量系数 k值的大小与强夯夯击能和场地介质条件有关 ;而衰减指数 β值的大小主要与场地介质条件有关。这些规律对于强夯振动效应的评价和岩土体动力学特性的研究具有重要意义

ANALYSIS OF FACTORS INFLUENCING THE ATTENUATION OF GROUND VIBRATION CAUSED BY HEAVY TAMPING

There are two important factors influencing the attenuation of ground vibration caused by heavy tamping,i.e.tamping energy and the properties of soil mass.Observation and analysis reveal some laws as follows:(1)the larger the tamping energy,the faster the attenuation of ground vibration;(2)the intensity of ground vibration is more sensitive near to the tamping point than that far away from it,which shows that the attenuation of ground vibration on a smaller distance from the tamping point is faster than that on a bigger one;(3)in the minus power function formula of ground vibration attenuation,equivalent coefficient k is associated with the heavy tamping energy and the condition of soil mass in the site;and attenuation index β is mainly related with the soil mass condition.These laws are significant not only to the assessment of ground vibration effect caused by heavy tamping,but also to the study of dynamic properties of soil mass.