Frost Resistance of High Early-Age Strength Concretes for Rapid Repair

摘要

The study presented herein examines frost resistance of different types of high early-age strength concretes made for rapid repair including Type Ⅲ, Type V and calcium sulfoaluminate (CSA) cement concretes. To this aim, high early-age strength concretes were made with different cement contents, including 386, 445, 504 and 564 kg/m~3 (650, 750, 850 and 950 lb/yd~3) for Type V cement concretes; 326, 386, and 445 kg/m~3 (550, 650 and 750 lb/yd~3) for Type Ⅲ cement concretes; and 326, and 386 kg/m~3 (550 and 650 lb/yd~3) for CSA cement concretes. This study also compares frost resistance of different types of high early-age strength concrete for a common cement factor of 386 kg/m~3. The results of this study showed that while CSA cement concretes had the fastest strength developments (shortest opening time which is the time to reach a minimum compressive strength of 20 MPa), they had considerably weak frost resistance. Type Ⅲ and Type Ⅴ cement concretes exhibited significantly superior frost resistance when compared to CSA cement concrete. The frost resistance reduced as cement content was increased and improved as curing age was extended.