TY - JOUR AU - Joyce Ogada AU - Sixtus Mwea AU - George Matheri PY - 2023/03/17 Y2 - 2024/03/28 TI - Performance of Plastic Waste and Waste Engine Oil as Partial Replacements of Bituminous Asphalt Concrete in Flexible Pavement JF - East African Journal of Engineering JA - EAJE VL - 6 IS - 1 SE - Articles DO - 10.37284/eaje.6.1.1144 UR - https://journals.eanso.org/index.php/eaje/article/view/1144 AB - Plastic waste is an emerging issue posing serious pollution problems to the environment. Waste Engine Oil has also become an environmental nuisance causing water pollution and soil degradation. New effective waste management options need to be considered, especially on recycling concepts. In addition to the emerging environmental issues, the sources of bitumen for road construction are continuously being depleted hence the need for innovative ways of sustaining road construction through the use of plastic waste and waste engine oil. This research project reviewed available literature on the concept of using waste plastic and waste engine oil as partial replacements of bitumen in road construction together while also carrying out the Marshall Stability test in both neat and bituminous mixes modified with plastic waste and waste engine oil. The optimum bitumen content was determined as 6% from the neat samples. Samples of the modified mix were then prepared with the percentage plastic content varying as 10%, 20%, 30%, and 40% of the mass of bitumen. The optimum plastic content was determined at 18% with a stability value of 8580N (an increase from 8337.4N for the neat samples). Samples with both plastic waste and waste engine oil replacements were prepared with 18% plastic waste being replaced with 10%, 20%, 30%, and 40% waste engine oil. The optimum replacement was determined at 19% giving the highest stability of 8820N (an increase of 2.8% from the plastic-only modified mix and an increase of 5.8% from the neat sample). With the utilisation of polymer-modified bituminous mix in highway construction, the pollution and disposal problems of waste plastic may be partly reduced. The use of innovative technology will not only strengthen road construction but also increase road life as well as will help to improve the environment ER -