Engineering Science and Technology, an International Journal (Feb 2022)
An experimental study and sustainability assessment of plastic waste as a binding material for producing economical cement-less paver blocks
Abstract
Recycling of plastic waste (PW) is one alternate approach to reduce the adverse impact on environment despite many control measures adopted around the world. Current study introduces various types of PW as a binding material to completely substitute cement to produce cement-less paver blocks. The constituent of paver block comprises of mixture of different types of PW in different proportion mixed with natural fine aggregate. PW in varying proportions of 40%, 50%, 60% and 70% were used to replace cement and investigated to ascertain achieving satisfactory physical and mechanical properties considering temperature effects. The compressive strength increases with increase in the proportion of plastic content. However, when exposed to very high temperature, its strength is reduced by 31.17%. According to the test results, the plastic paver block has a low water absorption potential. The average initial and final setting time of the binder was 19 and 24 minutes respectively. Abrasion test indicated low surface wear, displaying high durability with maximum of 2.56% wear. A trial foot path pavement was constructed using cement-less paver blocks and evaluation of its performance are discussed. The production of one cement-less paver block utilizes 1.8 kg PW. As per the economic assessment, an average unit cost of cement-less block is evaluated to be 35.39% less than concrete paver block. The findings indicate cost benefit of 29.39 to 32.15% when PW is utilised in construction. To evaluate the sustainability, an “Environmental Suitability Index” (ESI) is developed based on three parameters: embodied energy, life-cycle costs (LCC) and re-usability based on literature review. Three additional parameters: fire resistance, social impact and labour efficiency are introduced to further enhance the ESI in the current study.
