Effects of soil-foundation-structure interaction on fundamental frequency and radiation damping ratio of historical masonry building sub-structures
Effects of soil-foundation-structure interaction on fundamental frequency and radiation damping ratio of historical masonry building sub-structures
复制标题
土壤-基础-结构相互作用对历史砖石建筑下部结构基频和辐射阻尼比的影响
DOI：
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发表时间：
2019
影响因子：
4.6
通讯作者：
F. Silvestri
中科院分区：
文献类型：
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作者：
Annachiara Piro;F. de Silva;F. Parisi;A. Scotto di Santolo;F. Silvestri
对真实的案例研究的地震行为进行大规模模拟和法医分析通常基于简化的分析方法，以估计由动态土壤-基础-结构（SFS）相互作用引起的基频降低和辐射阻尼量。现有的封闭形式的解决方案的准确性可能是有限的，因为它们是通过单自由度的结构模型与浅刚性基础放置在一个均匀的，线性弹性半空间。本文研究了这些公式的有效性，在捕获的动态平面外响应的单承重墙内的无筋砌体建筑具有浅基础或地下楼层嵌入分层土壤。为了这个目的，分析预测的基础上更换振荡器的方法进行了比较，耦合SFS弹性模型的二维动态分析的结果在不同的岩土工程和结构特性，如土壤地层，基础深度和建筑层数。回归模型和相对土壤结构刚度参数提出了快速预测的频率降低引起的SFS相互作用，占存在的嵌入式基础，地下楼层和分层土壤。SFS相互作用的影响也进行了评估的等效阻尼比，简化方法的局限性。由于在这项研究中考虑的几何布局是相当经常在意大利和欧洲的建筑遗产，建议的程序可以扩展到类似的结构配置。
Large-scale simulations and forensic analyses of the seismic behaviour of real case studies are often based on simplified analytical approaches to estimate the reduction in fundamental frequency and the amount of radiation damping induced by dynamic soil-foundation-structure (SFS) interaction. The accuracy of existing closed-form solutions may be limited because they were derived through single degree-of-freedom structural models with shallow rigid foundations placed on a homogeneous, linear elastic half-space. This paper investigates the effectiveness of those formulations in capturing the dynamic out-of-plane response of single load-bearing walls within unreinforced masonry buildings having either a shallow foundation or an underground storey embedded in layered soil. To that aim, analytical predictions based on the replacement oscillator approach are compared to results of two-dimensional dynamic analyses of coupled SFS elastic models under varying geotechnical and structural properties such as the soil stratigraphy, foundation depth and number of building storeys. Regression models and a relative soil-structure stiffness parameter are proposed to quickly predict the frequency reduction induced by SFS interaction, accounting for the presence of an embedded foundation, an underground storey and a layered soil. The effects of SFS interaction are also evaluated in terms of equivalent damping ratio, showing the limitations of simplified approaches. Since the geometric layouts considered in this study are rather recurrent in the Italian and European built heritage, the proposed procedure can be extended to similar structural configurations.