Self-Consolidating Concrete for Use in Drilled Shaft Applications

Abstract

When conventional concrete is used in congested drilled shafts, coarse aggregates may bridge between reinforcing bars, which may lead to segregation of the concrete between the inside and outside of the reinforcing cage. The use of self-consolidating concrete (SCC) was evaluated to overcome this problem. The purpose of this study was to compare conventional drilled shaft concrete and SCC in a drilled shaft application. This paper reports on the data collected during the construction and evaluation of five drilled shafts that were 1.0 m in diameter and 7.3 m deep. Three shafts were constructed with conventional drilled shaft concrete and two shafts were constructed with SCC. The five shafts were exhumed, cleaned, and visually inspected to evaluate the quality of the as-built concrete. Cross sections of the exhumed shafts were cut in order to observe the uniformity and the amount of segregation between the inside and outside of the cage. Based on the results of this project, it is concluded that SCC may be feasible for use in congested drilled shaft applications.