Use of CEM Approach to Develop and Optimize High-Performance Underwater Concrete

The development and optimization of underwater concrete (UWC) characteristics (i.e., washout loss, threshold water head prior to concrete deterioration, and residual compressive strength) require considerable time, effort, and energy for testing. This paper seeks to propose a new testing method developed on the basis of the concrete-equivalent-mortar (CEM) approach to optimize and simplify evaluating the effect of mixture composition on washout characteristics of UWC cast under different conditions. Washout of CEM was determined using an adapted version of the commonly used CRD C61 test method as well as by simulation using an air-pressurized tube measuring 300 mm in height. Test results showed that CEM mixtures proportioned without coarse aggregates can adequately be used to predict washout characteristics of UWC. Statistical regression models were developed to enable direct estimation of washout loss and threshold water head of CEM and UWC mixtures. DOI: 10.1061/(ASCE)MT.1943-5533.0000254. (C) 2011 American Society of Civil Engineers.