A sustainable lightweight masonry unit: A bioplastic, biodegradable, modular proposal with interlocking qualities

After the study of the materials widely used in the construction industry and the development of sustainability, the examination of existing materials in terms of sustainability revealed the necessity of a sustainable alternative. In this context, it is aimed to present an alternative lightweight masonry unit that aims to make a significant contribution to waste reduction and energy efficiency in the construction field, that is recyclable and completely biodegradable, offering a completely innovative design and a new material. The raw materials of both aerated concrete and tuff-based construction blocks are cement-based and not suitable for recycling. The debris accumulated after the demolition of the structures built with these lightweight masonry blocks is transported to places away from the habited areas and stored there. This situation creates significant environmental health problems in the long run. Since the cement is used as an additive in such wastes and the materials are not suitable for recycling, their dissolution time in the environment is quite long. Similar to demolition processes, the production processes of existing aerated concrete and standard lightweight masonry units do not have an environmentally friendly and/or positive aspect in terms of waste reduction and sustainability. The alternative lightweight masonry unit, in other terms 'construction block', is the subject of this interdisciplinary study, and provides significant contributions to the environment in terms of both production and post-dissolution processes, waste reduction, and sustainability. When aerated concrete and tuff-based construction blocks are examined, it is known that these products produce some harmful substances such as aluminum, silicate, and radon gas. This situation carries significant risks for both human health and the environment. Within the scope of this study, the alternative construction block developed as a solution to these problems is obtained from bioplastic raw materials that are completely biodegradable. Bioplastics are completely environment-friendly and sustainable raw materials that are produced because of the recycling of starch and cellulose-based wastes. Another important feature of the developed construction block is its original design. The developed block is not monolithic like aerated concrete and other construction blocks. It has a completely modular and self-interlocking, clamping system and a design that allows horizontal and vertical installation transitions. The developed construction block provides significant advantages in terms of transportation and storage space, as it is lighter than the existing ones and occupies less space as it consists of six separate modular parts. The modular individual parts can be stacked and therefore create small volumes, thus significantly reducing transportation and storage costs compared to others. Compared to the construction blocks in current use which occupy the same volume logistically, an average of 4 times more area can be built with the developed alternative product, and while a standard construction block of the same dimensions is approximately 8 kg and an aerated concrete is about 5 kg, the proposed bioplastic alternative construction block is about 3 kg. During the product development process, simulations were carried out with dead loads, live loads, and earthquake loads on it, using the NX software, which offers simulation opportunities. In addition, lignocellulosic materials and graphene oxide are used as strength-increasing additives to find the right additives and the best combination to provide sustainability and the strongest and lightest biodegradable prototype. The experiments carried out with the construction offer advantages in many ways compared to the existing alternatives widely used in the construction industry and developed as eco-friendly, proving that it provides the same average strength values as the widely used current blocks.