초고성능 콘크리트의 수화발열 및 역학적 특성 모델

Abstract

Structural Engineering & Bridges Research Division, Korea Institute of Construction Technology, Goyang 411-714, KoreaABSTRACT Concrete has excellent mechanical properties, high durability, and economical advantages over other constructionmaterials. Nevertheless, it is not an easy task to apply concrete to long span bridges. That's because concrete has a low strengthto weight ratio. Ultra high performance concrete (UHPC) has a very high strength and hence it allows use of relatively small sectionfor the same design load. Thus UHPC is a promising material to be utilized in the construction of long span bridges. However,there is a possibility of crack generation during the curing process due to the high binder ratio of UHPC and a consequent largeamount of hydration heat. In this study, adiabatic temperature rise and mechanical properties were modeled for the stress analysisdue to hydration heat. Adiabatic temperature rise curve of UHPC was modeled superposing 2-parameter model and S-shaped func-tion, and the Arrhenius constant was determined using the concept of equivalent time. The results are verified by the mock-up testmeasuring the temperature development due to the hydration of UHPC. In addition, models for mechanical properties such as elas-tic modulus, tensile strength and compressive strength were developed based on the test results from conventional load test andultrasonic pulse velocity measurement.Keywords : UHPC, heat of hydration heat, adiabatic temperature rise curve, equivalent time