ABSTRACT
ECC is classified into two categories: self compacting cast ECC, and sprayed ECC. In this study the focus was on sprayed ECC because it is a more economical application method as it does not require setup of formwork. A typical mix design of sprayed ECC is shown in Table 1, revealing that
1 INTRODUCTION
1.1 Background
Reinforced concrete bridge construction in New Zealand became common after the 1950s. Due to the nature of design and construction practice during this period, many of the bridges now have insufficient cover concrete compared to the current New Zealand concrete code (NZS 2006). As a result of insufficient specified cover thickness and lack of supplementary cementitious material, many bridges now exhibit signs of reinforcement corrosion. To extend the service life of these deteriorated bridges, immediate remediation is necessary and can be categorised into two procedures: firstly, removal of existing chloride ions and replacement of damaged steel reinforcement; and secondly, the application of new cover concrete to delay future chloride ingress. This study focused on the second step and investigated the effectiveness of sprayed Engineered Cementitious Composite as a cover concrete for repair work.
