ABSTRACT

Earthen heritage represents an important legacy regarding construction history and technological development, with a significant cultural value that must be preserved. According to UNESCO, around 10% of the World Heritage is built using earth, and 57% of these heritage structures are in danger. Although the interest regarding earthen heritage has grown in the last few years, there is still a significant lack of knowledge in terms of material characterization, especially from conservation science point-of-view. In particular, tests regarding water absorption are always difficult to perform with a material that changes completely when in contact with water. Indeed, due to the presence of clay particles, a normal capillarity test is almost impossible to perform. Moreover, water is responsible for a significant number of degradation phenomena often found in earthen heritage. As a result, there is an urgent need to develop suitable water repellent treatments and to evaluate their efficiency. For this reason, this study focuses on the contact sponge method to assess water absorption rates for adobe and for rammed earth specimens treated with three different water repellents — siloxane, linseed oil, and beeswax. Two sets of specimens were prepared and tested, showing that this method can represent an effective way to measure initial water absorption in earthen materials, and promising results from the tested water repellent treatments were found.

摘要

土质遗产是关于建筑历史和技术发展的重要遗产，具有必须保存的重要文化价值。据联合国教科文组织称，大约 10% 的世界遗产是用泥土建造的，其中 57% 的遗产结构处于危险之中。尽管过去几年对土质遗产的兴趣有所增加，但在材料表征方面仍然严重缺乏知识，特别是从保护科学的角度来看。特别是，对于与水接触时完全变化的材料，总是很难进行有关吸水性的测试。事实上，由于粘土颗粒的存在，几乎不可能进行正常的毛细作用测试。而且，水是造成土质遗产中常见的大量退化现象的原因。因此，迫切需要开发合适的防水处理并评估其效率。出于这个原因，本研究的重点是接触海绵法，以评估用三种不同防水剂（硅氧烷、亚麻籽油和蜂蜡）处理的土坯和夯土标本的吸水率。准备并测试了两组试样，表明该方法可以代表一种有效的方法来测量土材料的初始吸水率，并且从测试的防水处理中发现了有希望的结果。本研究的重点是接触海绵法，以评估土坯和夯土样品的吸水率，这些样品用三种不同的防水剂（硅氧烷、亚麻籽油和蜂蜡）处理。准备并测试了两组试样，表明该方法可以代表一种有效的方法来测量土材料的初始吸水率，并且从测试的防水处理中发现了有希望的结果。本研究的重点是接触海绵法，以评估土坯和夯土样品的吸水率，这些样品用三种不同的防水剂（硅氧烷、亚麻籽油和蜂蜡）处理。准备并测试了两组试样，表明该方法可以代表一种有效的方法来测量土材料的初始吸水率，并且从测试的防水处理中发现了有希望的结果。