Experimental Evaluation of Waste PET Bottles as a Sustainable Building Material

Abstract

Sustainable development and the preservation of the natural environment are two concepts that are becoming increasingly important in the construction sector, leading to a growing interest in the development of ecofriendly building solutions. In this regard, the use of waste polyethylene terephthalate (PET) bottles as a construction material is an interesting alternative that can help to reduce the environmental impact of the building activity at little or no cost, while providing a second life to a material that is one of the main sources of pollution. The present study analyses the mechanical behavior of PET bottles for their use as construction materials, carrying compression tests to assess the elastic properties of PET bottles filled with sand or plastic waste, both alone and embedded in a concrete matrix. In a second part of the study, a finite-element method model of an existing water tank built with PET bottles in Tanzania is developed and tested. The results obtained show the suitability of the composite bottle-and-concrete samples as a sustainable construction technique. Environmental sustainability is an increasingly important aspect in our society and all its productive sectors, and the construction industry is no exception. In this regard, diverse initiatives have been proposed to introduce waste polyethylene terephthalate (PET) bottles as a construction material, which provides three direct benefits: offering a low-cost construction material, reducing the consumption of new resources, and giving a second life to waste material that would otherwise end up in landfills or in the environment. However, to use these new sustainable materials in safety conditions, it is necessary to understand their mechanical and structural behavior and treat them with the same rigor as we treat conventional construction materials such as concrete or steel. In this sense, in the present study, a testing campaign is conducted to assess the compressive strength of PET bottles filled with sand or plastic, as well as their combined use with concrete to form walls in buildings or water tanks.