ABSTRACT

Existing masonry buildings and infrastructures are often characterized by curved elements like arches, where the settlements could induce damages up to compromising their stability. Curved elements are very sensitive to settlements due to the modification of the lateral thrust. The effects of settlements could be very critical on heritage buildings, where the intrados of curved elements are often characterized by decorated plasters. These issues caused by settlements are very important also in the infrastructures, where the displacement of the foundations could affect the main structural elements. When dealing with existing heritage buildings the analysis cannot be focused on the ultimate state only. In order to preserve the heritage value, it is important to refer to elastic behaviour to minimize the damages at serviceability limit state (e.g., newly defined artistic limit state). In this work, an existing theory has been used to obtain the closed-form solution for a specific curved system (i.e., Standard arch). The behaviour of semi-circular and parabolic curved elements is investigated under several load conditions of vertical loads and settlements. The solutions were numerically estimated according to the Principle of Virtual Works and are dimensionless in order to obtain generalizable results. A parametrical analysis was performed, providing several useful design charts to assess the impact of settlements and vertical loads on the behaviour of curved elements. The closed-form solution derived for standard arch if applied to different cases yields to approximated solutions and the scatter was estimated by comparing them with refined numerical evaluations. The outcomes of this work are useful tools to assess the sensitivity to structural damage of curved elements under settlements.

摘要

现有的砖石建筑和基础设施通常以拱门等弯曲元素为特征，在这些元素中，定居点可能会导致破坏，甚至损害其稳定性。由于侧向推力的改变，弯曲单元对沉降非常敏感。定居点的影响可能对遗产建筑非常重要，其中弯曲元素的内部通常以装饰灰泥为特征。这些由沉降引起的问题在基础设施中也非常重要，地基的位移可能会影响主要的结构元素。在处理现有的遗产建筑时，分析不能只关注最终状态。为了保护遗产价值，重要的是参考弹性行为以最大限度地减少可使用极限状态下的损害（例如，新定义的艺术极限状态）。在这项工作中，现有理论已被用于获得特定弯曲系统（即标准拱门）的封闭形式解决方案。在垂直荷载和沉降的几种荷载条件下研究了半圆形和抛物线弯曲单元的行为。解决方案是根据虚拟工程原理进行数值估计的，并且是无量纲的，以获得可推广的结果。进行了参数分析，提供了几个有用的设计图表来评估沉降和垂直载荷对弯曲元件行为的影响。如果应用于不同的情况，标准拱形的封闭形式的解会产生近似解，并且通过将它们与精细的数值评估进行比较来估计分散。