Abrasion Resistance of Concrete with Pulverised Fuel Ash

Abstract

This thesis describes an investigation of the effect of abrasion resistance of concrete containing pulverised fuel ash.T he test method is based on wear produced by rotating steel wheels running in a circular path. The abrasion resistance is expressed in terms of the depth of the groove produced by 15 minutes of abrasion. This test has been used in the present study to assess the abrasion resistance of the various test surfaces. Numerous factors influence the abrasion resistance of floor slabs, a most significant being curing, strength grade and trowelling intensity. These factors have not been adequately tested with mixes containing pulverised fuel ash, and so this research work was structured to examine the resistance to wear of concrete with pulverised fuel ash. The experimental investigation was formulated in three separate but related phases and these may be briefly summarised as follows: 1. The development of basic mix design data from a series of trial mixes containing PFA to be used for the design of the mixes for the main investigation. 2. To study the abrasion resistance of concrete mixes containing PFA using the rolling wheel apparatus developed at Aston University. This macro study of abrasion resistance to place particular emphasis on the influence of the curing regime and the age at test on the performance of the test slabs. 3. Through a parallel study, of microscopic characteristics of individual mixes, to identify those factors that particularly influence the abrasion resistance of concrete mixes containing PFA. The experimental results revealed that positive curing has a major influence on the abrasion resistance of PFA concretes. With a given water/cementitious material ratio, the abrasion resistance is influenced by the combined effects of PFA content—and curing regime. Further improvements in abrasion resistance were detected at a later age. Well cured concrete appeared to be relatively independent of PFA content up to 40 percent but the performance of air cured slabs appears to be inversely proportioned to PFA content.