摘要
根据对两规分析,有相同点,即均将匀质半空间体系土层地基阻尼比折减50%;不同点在于ACI351的埋深阻抗很高;阻尼比虽己折减50%,仍然较大,有的实例接近0.707;但其土层的刚度偏低。阻尼比大后不起作用,由刚度控制线位移,从而在大阻比尼低刚度的土层使线位移增大而不经济。最后,从实用出发,附地基阻尼比说明。
From the analysing of tow codes,the same point is found as the damping ratio of homogeneous subsoil being redused 5 o%; and the different point at ACI 351, that the embeded damping parameter being very high, the embeded damping ratio is larger, though having been reduced 50% alredy. Some examples show being about 0.707, during the stiffness of subsoil being low. Since the larger damping ratio is not effective at all, then the displacement is cortrolled by stiffenees. Therefore in the case of larger damping ratio and lower stiffnees, it would cause the increase in liner diplacemnmt and would be not economical. As a result, we have a practical solution with related subsoil damping ratio explanation.
引文
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