NONDESTRUCTIVE TESTING OF ULTRA-HIGH PERFORMANCE CONCRETE TO EVALUATE FREEZE-THAW RESISTANCE

摘要

Recently increased attention has been given to materials, which could meet certain strength and durability requirements. Ultra high performance concrete (UHPC) is one of the materials which possess such properties. UHPC has excellent durability and mechanical properties and could be suitable for various construction applications, however all construction over time in aggressive environment loses its original designed properties. In this article researched one of the most important durability parameter?–?freeze-thaw resistance of concrete. This durability parameter is significant for constructions and materials used in Lithuania. Nondestructive test methods are one of the ways, which are suitable to investigate durability properties of UHPC. Each of the methods has its advantages or disadvantages and depending on environment will presents different reliability results. Durability properties of UHPC were investigated by ultrasonic and dynamic modulus of elasticity methods. The reliability of these test methods was verified by determining the compressive strength, and surface defects were visually inspected by fluorescence method. There are a few publications about freeze-thaw resistance of UHPC and fewer articles about concretes prediction to severe frost damage, however such research in Lithuania is not done at all.