Quantification of Variability in Pond Ash Concrete and Its Effect on the Seismic Safety Performance of Reinforced Concrete Buildings

Abstract

In this study, an attempt was made to use pond ash (PA), which is an industrial waste generated in power plants, as a replacement for fine aggregates (FA) in concrete. An experimental program was conducted on the mechanical properties (compressive strength, split-tensile strength, and flexural strength) of pond ash concrete. Five concrete mixes with varying proportions of pond ash replacing fine aggregates were designed to cast a total of 450 concrete samples. Thirty-two [two-parameter (2P), three-parameter (3P), and four-parameter (4P)] probability distributions were taken into consideration, and the statistical goodness-of-fit (GOF) tests Kolmogorov-Smirnov (KS), Kolmogorov-Smirnov-Lilliefors (KSL), Anderson Darling (AD), and chi-squared (CS) were carried out. The peak values for compressive strength, split-tensile strength, and flexural strength were observed at 20% replacement of FA by the PA. Based on the GOF test ranks, the most suitable probability distribution for modeling variations in compressive strength was the Cauchy distribution (2P). Similarly, Johnson-SB (4P), and Gumbel-Min (2P) were found to be the best distribution for the split-tensile strength and flexural strength, respectively. With an increase of pond ash substitution from 0% to 20%, there is a decrease in the probability of failure, and a further increase in FA substitution causes a decrease in concrete strength, which led to an increase in the probability of failure as shown by the fragility analysis.