CORRELATION BETWEEN COMPOSITION OF MASONRY BLOCKS USING RECYCLED RUBBER AGGREGATES AND PROFITABILITY OF PRODUCTION LINE

A correlational study between the composition of masonry blocks with recycled rubber aggregates and the profitability of their production line was carried out. Masonry blocks were designed and manufactured with different contents of rubber aggregates from end-of-life tires. We started from a factorial design of experiments with response surface L4 (22). The factors considered were aggregate granulometry, water/cement ratio and rubber content. The outputs of the experiment were the ultimate compressive strength and the profitability of the production line (IRR/NPV). A model was defined that correlates the input factors with the defined responses. Through an ANOVA, the significant factors on the profitability of the production line in different production scenarios were determined. It was found that there is an inversely proportional relationship between the amount of rubber aggregate and the compressive strength. The maximum aggregate content that allows meeting the resistance requirements of the NTE INEN 3066 standard was 10% (p/p). On the other hand, from the economic-financial analysis it is concluded that the maximum economically profitable rubber content is 5% (p/p). These results make it possible to define the limits of profitability of a production line of masonry blocks that comply with current regulations.