Effects on Strengths of Cement Mortar When Using Incinerator Bottom Ash as Fine Aggregate

Abstract

The main purpose of this paper is to study the feasibility of using the Incinerator bottom ash fine aggregate to replace natural fine aggregate in the cement mortar products. The research adopts high cement content mortar to conduct the experiment, in which the weight ratio of cement/aggregate is 1/2. The experiment uses Incinerator bottom ash fine aggregates, which passes through #16 sieve, and natural sand of the same size as the aggregate, and separates mortar specimens in- to two main categories based on different W/C ratio. Moreover, different proportions of furnace slag and F-class are used to replace a portion of cement so as to explore the influence on strength of Incinerator bottom ash aggregates mortar by adding the two admixtures. The study shows that, based on the 1:2 cement/aggregate weight ratio, Incinerator bottom ash fine aggregates mortar, unit weight around 1.8 g/cm3, is 20% lighter natural fine aggregate mortar, unit weight around 2.2 g/cm3. The Incinerator bottom ash fine aggregates mortar can only reach 60%-70% the compressive strength of natural fine aggregates mortar. Direct tensile strength and flexural tensile strength tests are 15% and 30% of compressive strength respectively, due to the irregular strength development, which does not follow general concepts, such as low W/C ratio and mineral admixtures will not necessarily help in strength development in Incinerator bottom ash fine aggregates mortar.