Sugarcane ash: Compressive strength and rheology of a self-compacting concrete

Authors

Vega Anticona, Alexander

Mego Zapata, Juan

Meza Caballero, Kevin

Chávez Novoa, Danny

Alvarado, Cinthya

Alvarado-Quintana, Hernán

Vásquez Alfaro, Ivan

Abstract

In the present research work, the mechanical and rheological properties of a self-compacting concrete (CAC) were determined, with additions of sugar cane ash (CCA) as a pozzolanic material; plus, a superplasticizer additive to maintain workability. The mechanical properties were determined as a function of curing time. The CCA was collected from the cane fields during the harvest in the province of Ascope (Trujillo - Peru) after burning them, then it went through a grinding process using only the Nº 325 mesh pass-through in this case; the Portland cement (PC) used was type I; the fine aggregates (coarse sand) and coarse aggregate were acquired from the quarries of El Milagro (Trujillo-Peru). The superplasticizer additive used was Euco Plastol 3000PC. The mix design was based on the recommendations stipulated in ACI – 211, the percentages of CCA additions were (0.5, 1.0, 1.5 2.0, 2.5, 3.0 and 3.5) %, and the superplasticizer additive was used at (0.69, 0.72 0.77, 0.85, 0.98, 1.18, 1.45 and 1.89)% in both cases with respect to the weight of the cement used, the data collection times of mechanical tests (ASTM C39 and ASTM C469) were performed at (7, 14, 28 and 56) days after making the mixtures; In addition, characterization was carried out in the fresh state of the mixture, according to the ASTM C1611 and ASTM C1621 standards and the EFNARC (2002) and GPE (2005) specifications in order to evaluate their fluidity, the CCA were characterized by ATD, ATG and RDX. The aggregates were characterized by the standards ASTM C136, ASTM C566, ASTM C29, ASTM C127 and ASTM C128. From the results obtained, we can mention that the addition of CCA exceeds the limit of the recommended water/fines ratio, although it has shown to improve the effectiveness of self-compacting concrete, partially; the evaluation of the filling capacity determined that the samples with the addition of CCA (0.5, 1.0, 1.5 and 2.0) % are class SF2, while the samples with the addition of (2.5, and 3.5) % belong to the SF3 class ; the passability analysis according to ASTM 1621 classified the samples with pozzolan addition of (0.5, 1.0, 1.5, 2.0, 2.5 and 3.0) % as mixtures with no visible blocking, however for the sample with 3.5% of addition presents an apparent blockage, with respect to fluidity all samples were classified as VS2 type, however the samples with addition of CCA at 3.0 and 3.5% present a high degree of viscosity; the superplasticizer additive is the factor with the greatest influence on the rheological properties of the CAC, the mechanical properties increased as a function of the curing time, among the values obtained are those of 622 kg/cm2, in the case of compressive strength and a and modulus of elasticity of 317.962 kg/cm2, which are values that exceed the samples without the use of CCA, so these are considered to have pozzolanic properties