Wood Ash Effect on Cement Based Self-Compacting Mortars

Abstract

In this experimental study, the effect of wood ash (WA) substituted into Portland cement (PC) at variable proportions by volume on the fresh state, hardened state, and microstructure of self-compacting mortars (SCMs) was investigated. In the designed SCMs, WA was substituted into PC at 5% increasing ratios in the 0%-30% band. A total of 84 40*40*160 mm prism specimens and 42 50*50*50 mm cube specimens were produced for 7 different SCM designs. V-funnel and slup flow test were done according to EFNARC kriteria. Hardened state tests were carried out at 7, 28, 56 and 90 days with oven dry unit volume weight, porosity, capillary water absorption, flexural tensile, compression and splitting tensile tests. In addition, WA used in the mixture and after 28 days of water curing, samples containing WA 0%, 15%, 30% were evaluated after microstructure analysis. According to the results of the study, increasing WA substitution rate has a determining effect on the fresh state properties. Increasing WA substitution has a negative effect on flexural tensile strength and compressive strength and a variable effect on splitting tensile strength. Increasing the amount of WA increases the unit volume weight and decreases the porosity at 5% substitution. For the other substitution cases, the unit volume weight decreases and porosity increases. Except for the control mixture, Magnesium calcite and Aluminum-based compounds were detected in microstructure examinations of SCMs.