Abstract

Eastern Sicily’s historic buildings are characterized by an almost uniform use of local and naturally available calcareous and lavic stone as aggregate. Also, ancient mortars comprise of lime or cement-lime binder. Very limited studies concerning the mechanical properties of the ancient mortars have been accomplished. In this paper, mortar samples collected from the surviving heritage masonry structures in eastern Sicily were selected to assess their composition. Due to limitations of dimensions, shape and cohesiveness of mortar samples collected from historic buildings, not laboratory test can be applied on the samples. Then, new mortar samples were constructed matching those of historic buildings in order to determine their mechanical properties. Hence, the restored ancient mortar, were tested after 30-60-90 days of curing and finally after 20 years of curing. The data obtained was, then compared each other. To this aim, two series of mortar were performed for a total of 400 samples. The composition of the mortars differs in according to ancient recipes determined in the laboratory by means of the chemical attack of the samples directly taken from historic buildings. The time effects as well as the aggregate (sand) influence were analyzed. To this aim bending, compression and tensile tests were carried out on all the specimens. The data obtained show after 20 years a reduction between 10 and 15% of the compressive strength in mortar studied. All of these data could be very useful for creating compatible mortar recipes for restoration works as well as to define mechanical features of ancient mortar in modeling process.

摘要

东西西里岛的历史建筑的特点是几乎统一使用当地和天然可用的钙质和熔岩作为骨料。此外，古代砂浆由石灰或水泥石灰粘合剂组成。关于古代砂浆的力学性能的研究非常有限。在本文中，选择了从西西里岛东部幸存的砖石结构中收集的砂浆样品来评估它们的成分。由于从历史建筑中采集的砂浆样品的尺寸、形状和粘合性的限制，不能对样品进行实验室测试。然后，建造与历史建筑相匹配的新砂浆样品，以确定它们的机械性能。于是，修复的古砂浆，在固化 30-60-90 天后进行测试，最后在固化 20 年后进行测试。然后将获得的数据相互比较。为此，对总共 400 个样品进行了两个系列的砂浆。砂浆的成分根据实验室中通过直接取自历史建筑的样品的化学侵蚀确定的古代配方而有所不同。分析了时间效应以及集料（沙子）的影响。为此目的，对所有试样进行弯曲、压缩和拉伸试验。获得的数据显示，20 年后研究的砂浆的抗压强度降低了 10% 到 15%。所有这些数据对于为修复工作创建兼容的砂浆配方以及在建模过程中定义古代砂浆的机械特性非常有用。