Adobe Blocks in the Center of Portugal: Main Characteristics

Earth construction is the oldest building practice known. The adobe is a simple and sustainable type of earth construction. Many of adobe buildings are in an advanced state of degradation due to the effect of natural agents and to the aging of constituent materials. There is a strong concern with these materials, because in addition to their sustainability, they are also the mark of generations and heritage of each region and country. Therefore, it is necessary to have deep knowledge of the different compositions, as well as of other properties of the adobes, to infer which compatible materials to use in the interventions taking into account each type of adobe blocks. In this article, 41 different adobe blocks from the central coast of Portugal were characterized. It is concluded that there are 5 main types of adobes, which stand out for their visual properties (color and texture), 4 types of adobe blocks according to the mineralogy, and 3 groups of adobe blocks regarding the other properties such as chemical composition and their mechanical behaviour. In general terms, adobes consist mainly of quartz, calcite, and phyllosilicates. The studied adobe blocks have mechanical strengths ranging from 0.30-3.50 MPa.

Automated summary

Earth construction, specifically adobe, is a sustainable building practice facing degradation due to natural factors and aging materials. Understanding different compositions and properties of adobes is crucial for choosing compatible materials for interventions. By characterizing 41 adobe blocks from Portugal, it was found that there are 5 main types based on visual properties, 4 types based on mineralogy, and 3 groups based on other properties like chemical composition and mechanical behavior. The studied adobe blocks have mechanical strengths ranging from 0.30-3.50 MPa.