ABOUT THE INTERNATIONAL CONCRETE ABSTRACTS PORTAL

  • The International Concrete Abstracts Portal is an ACI led collaboration with leading technical organizations from within the international concrete industry and offers the most comprehensive collection of published concrete abstracts.

International Concrete Abstracts Portal

  


Title: Marine Concrete Mix Design - Combining Durability And Placeability

Author(s):

Publication: CIA

Volume:

Issue:

Appears on pages(s):

Keywords:

DOI:

Date: 2/13/2011

Abstract:
Mix designs to meet marine durability requirements can often compete with placing issues. This paper takes a practical look at meeting all the needs of concrete for marine structures by outlining mix development on a number of structures. For a WA power station the initial concrete, with a high content of coarse slag and a deficit of fine fines, had very high plastic settlement. Mix trials identified the most suitable way of reducing bleed. For a Queensland jetty trial mix results showed how sand, pozzolan and admixture selection affected sorptivity while mix design and practical mixing determined slump retention. For the Jervoise Bay wharf, with soffits just above sea-level, an inhibitor, low water:binder ratio and low sorptivity were specified to provide corrosion protection. The resultant high cement content and inhibitor caused difficulties in maintaining the required thermal differentials to 25oC in the decks up to 3m thick. Adiabatic test results were used in a computer programme to assess insitu temperature profiles in various environmental conditions and with different insulation. Results show the dilemmas of too little or too much insulation and too much or too little water in a location where thermal cracking is not tolerable. The development of the marine exposure classification and the appropriate sulphate resisting cement system for a petrochemical plant in Vietnam is discussed. Finally the issue of performance or prescription based specification is discussed.