A number of simple models containing frequency-independent elements have been presented to simulate unbounded soil in dynamic soil-structure interaction problems. Most of the existing models were established through a traditional top-down strategy with significant computational complexities. This study develops an alternative method based on a bottom-up strategy, in which the optimal element layout is determined by an adaptive refinement procedure considering finite modularized units. This innovation eliminates the need for lengthy procedures to establish simple models. The proposed three-parameter model is used to simulate the layered soil for rigid foundations undergoing vertical vibration. The accuracy of the model is validated by comparing the magnified responses obtained when a foundation is subjected to harmonic forces with those obtained via theoretical solutions and advanced numerical simulations. The proposed model is found to effectively simulate a layered half-space and a soil layer on rock. Compared to two existing models, the proposed model performs better and has fewer parameters and a higher degree of adaptivity. Therefore, the adaptivity of simple models obtained using the proposed method may allow simulation of a variety of layered soil systems.

中文翻译：

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一种模拟垂直动力荷载作用下层状土中浅地基频变响应的自适应有限单元法

已经提出了许多包含与频率无关的元素的简单模型来模拟动态土壤-结构相互作用问题中的无界土壤。大多数现有模型是通过传统的自上而下的策略建立的，具有显着的计算复杂性。本研究开发了一种基于自下而上策略的替代方法，其中最佳单元布局由考虑有限模块化单元的自适应细化程序确定。这一创新消除了建立简单模型所需的冗长程序。提出的三参数模型用于模拟承受垂直振动的刚性地基的分层土壤。通过将基础受到谐波力时获得的放大响应与通过理论解决方案和高级数值模拟获得的响应进行比较，验证模型的准确性。发现所提出的模型可以有效地模拟分层的半空间和岩石上的土层。与现有的两种模型相比，所提出的模型性能更好，参数更少，自适应程度更高。因此，使用所提出的方法获得的简单模型的适应性可以允许模拟各种分层土壤系统。所提出的模型性能更好，参数更少，自适应程度更高。因此，使用所提出的方法获得的简单模型的适应性可以允许模拟各种分层土壤系统。所提出的模型性能更好，参数更少，自适应程度更高。因此，使用所提出的方法获得的简单模型的适应性可以允许模拟各种分层土壤系统。