The fundamental mode shape of layered soil profiles is a key site response parameter, it has been adopted into the Japanese seismic code to represent the shape of the soil displacement response along the vertical direction. In this study, a simple approach for estimating the fundamental mode shape of layered soil profiles is developed. The proposed approach can directly model the fundamental mode shape and can be conveniently implemented using arithmetic operations, thus making it suitable to be used by the engineers. The assessments of the proposed approach using a series of layered soil profiles demonstrate that it can produce results in close agreement with the actual results.

中文翻译：

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一种估算层状土壤剖面基本振型的简单方法

层状土剖面的基本振型是一个关键的场地响应参数，它已被日本地震规范采用来表示沿垂直方向的土位移响应的形状。在这项研究中，开发了一种用于估计层状土壤剖面基本模式形状的简单方法。所提出的方法可以直接对基本模式形状进行建模，并且可以使用算术运算方便地实现，因此适合工程师使用。使用一系列分层土壤剖面对所提出方法的评估表明，它可以产生与实际结果非常一致的结果。