Comparison of types of protection applicable to bamboo-guadua structures for elements exposed to weathering

Bamboo has an important historical background in construction worldwide; however, at present, some construction practices are based on historical experiences, which, although they represent a great cultural value, show technical gaps that hinder the proper use, implementation, and preservation of the material. Therefore, this study seeks to contribute to the knowledge about the preservation of bamboo-guadua constructions through preventive maintenance against the action of atmospheric agents. This study documents the deterioration of bamboo-guadua samples, preserved and unpreserved, protected with 4 different commercial products and unprotected, unexposed, and exposed to weathering for 9 months, in order to compare their deterioration and behavior, as well as their pathological processes. The methodology used was to monitor the behavior of this material by means of a visual inspection through photographic documentation and analysis with a scanning electron microscope, which seeks to identify the changes in the surfaces of the exposed guadua, comparing it to unexposed elements. As preliminary results, it was found that the protected samples show similar deteriorations to unprotected samples, being lower in preserved samples than in unpreserved samples exposed to weathering. Also, it was found that protective treatments are not sufficiently effective against the action of atmospheric agents, and that the surface of the material, although it shows a change in color and cracks, does not necessarily indicate a loss of compressive strength. As well, the results of this study contribute to decision-making on the use of bamboo outdoors, the maintenance products to be used, the details of the deterioration at the dermis and epidermis levels, as well as the relationship between the presence of deterioration and the mechanical behavior of the material.