The paper addresses the failure analysis under horizontal loads of the most ancient body of the National Palace of Sintra, Portugal: the Bonet building. This is a URM construction built on top of Arabic foundations during the reign of King Denis of Portugal around 1281; since then, few alterations have been made to the building. Due to the exemplary conservation of the whole palace, a few crack patterns are identified only on the top floor of the Bonet building, an area that is not open to visitors and that will soon undergo restoration works. The seismic vulnerability assessment of this building is carried out following two different approaches, enacted in two distinct numerical models: the so-called Equivalent Frame Method (EFM) and the Finite Element Method (FEM) developed in 3Muri and ABAQUS software, respectively. Both approaches adopt a numerical procedure based on the use of nonlinear static analyses, introducing “equivalent” boundary conditions that are defined to consider, approximately and conventionally, the possible interaction effects among the different parts of the structure. To minimize the multiple uncertainties usually existing in complex masonry buildings, whether related to geometry or masonry mechanical properties, a detailed structural survey is conducted through the laser scanning technology as well as in situ experimental tests. Different types of experimental tests are carried out, both non- and semi-destructive, including a Ground Penetrating Radar test, ambient vibration tests, flat-jack tests, and the collection of masonry samples. All these tests are important to adequately characterize the building and to calibrate the numerical models. Moreover, these tests enable the extraction of values for the mechanical properties of the rubble stone masonry that are used in the later numerical simulations on the Bonet building and, most importantly, can be used as a reference for future works regarding historical Portuguese monuments of the same period. Afterwards, the results obtained from the nonlinear static analyses with the two different software 3Muri and ABAQUS are presented and discussed. Specifically, the differences in modelling strategies and characterization of materials between the two software are considered with special regard to their feasibility, required computational effort, data availability and applicability to large scale structures. Efforts to calibrate and obtain the same behavior of the building for the different software are made, involving geometry, boundary conditions and characterization of the material constitutive laws. Eventually, a nonlinear dynamic analysis is carried out in ABAQUS to further assess the seismic vulnerability of the Bonet building; a spectrum-compatible accelerogram is applied to the numerical model, and the time-history of displacements in relevant control points of the buildings are extracted and discussed.

本文介绍了葡萄牙辛特拉国家宫殿最古老的建筑：博内特大厦在水平荷载作用下的失效分析。这是URM建筑，建于1281年左右葡萄牙国王丹尼斯统治时期的阿拉伯基础之上；从那以后，对该建筑物进行了很少的改动。由于整个宫殿的典范保护，仅在Bonet大楼的顶层发现了一些裂缝图案，该区域不对游客开放，不久将进行修复工作。该建筑物的地震易损性评估是通过两种不同的方法进行的，分别采用两个不同的数值模型：分别在3Muri和ABAQUS软件中开发的等效框架法（EFM）和有限元法（FEM）。两种方法都采用基于非线性静态分析的数值程序，引入“等效”边界条件，定义该边界条件是为了近似，常规地考虑结构不同部分之间可能的相互作用。为了使复杂的砖石建筑中通常存在的与几何形状或砖石力学性能相关的多种不确定性最小化，通过激光扫描技术以及原位实验测试。进行了不同类型的实验性测试，包括非破坏性和半破坏性的，包括探地雷达测试，环境振动测试，平顶测试以及砌体样品的收集。所有这些测试对于充分表征建筑物和校准数值模型都很重要。此外，这些测试还可以提取瓦砾石砌体的机械性能值，这些值将在以后的Bonet建筑物数值模拟中使用，最重要的是，可以用作将来有关葡萄牙历史遗迹的工作的参考。同一时期。然后，介绍并讨论了使用两种不同的软件3Muri和ABAQUS从非线性静态分析中获得的结果。特别，考虑到这两种软件在建模策略和材料表征方面的差异，并特别考虑了它们的可行性，所需的计算工作，数据可用性以及对大型结构的适用性。努力针对不同的软件进行校准并获得建筑物的相同性能，包括几何形状，边界条件和材料本构定律的表征。最终，在ABAQUS中进行了非线性动力学分析，以进一步评估Bonet建筑的地震脆弱性。将频谱兼容的加速度计应用于数值模型，并提取和讨论建筑物相关控制点中位移的时程。