Performance analysis of paver blocks manufactured with an incorporation of waste from the disposable straw industry

Civil construction has been seeking sustainable practices with the insertion of waste in their products. The objective of this work is to study for the first time the use of shavings generated in the production of disposable straws, without reprocessing by extrusion, in paver blocks as an alternative to commercial polypropylene fiber, because the production and use of disposable straws generate a significant portion of plastic waste worldwide. The concrete was produced with a ratio (by weight) of 1:1.5:1.5:2.5 for cement, fine sand, coarse sand, and gravel. Straw shavings were submitted to surface treatment using a 0.25 M sodium hydroxide solution and added to concrete at a volumetric content of 0.5%. The physical and mechanical properties of the mixture were analyzed and compared to those of reference samples and those produced by adding commercial fibers. The compressive strength at 28 days of the samples with the addition of drinking straw shavings (36.47 ± 1.63 MPa) was lower than the reference samples (43.61 ± 2.16 MPa) and those with commercial polypropylene fibers (44.23 ± 1.79 MPa), but respected the 35 MPa limit required by the technical standard. The water absorption of paver blocks containing commercial fibers (5.6 ± 0.1%) exceeded that of paver blocks containing shavings (4.9 ± 0.3%). The lower water absorption reduces the entrance of corrosive ions which directly collaborate with the material deterioration process. There is no statistical evidence that the incorporation of waste reduces the abrasion resistance and flexural tensile strength of the concrete parts.