Continuous improvement of concrete properties using recycled cardboard ash: A sustainable alternative to cement

The use of alternative materials in construction is a growing trend aimed at reducing the environmental impact of cement production. This study evaluated the effect of cardboard ash as a partial cement substitute on the properties of concrete. An experimental methodology was used with 2.5%, 5% and 7.5% additions of cardboard ash. The results indicated that concrete with 5% cardboard ash reduced the absorption speed to 0.229 mm at 831.38 s^½ compared to the reference concrete. In addition, an improvement in mechanical strength was observed, with increases of 15.10%, 16.99% and 18.41% in compressive strength, and 13.76%, 19.63% and 27.33% in flexural strength, highlighting the potential of cardboard ash to optimize concrete properties. These results were evaluated according to ASTM standards. In conclusion, the use of cardboard ash in concrete production contributes significantly to sustainability by reducing CO(2) emissions, making this material a greener and more environmentally efficient option.