Interesting fact was observed with dynamic modulus of elasticity test method.
Although the tendencies with both nondestructive test methods remained similar, however relationship between mass losses of salt-scaling and dynamic modulus of elasticity at 40 cycles was more than 2 times weaker (correlation coefficient [R.
Also were made relationships between compressive strength and dynamic modulus of elasticity or dynamic modulus of elasticity and ultrasonic pulse velocity also showed insufficient correlation.
All applied test methods were not sensitive enough for structure analysis had very little change of ultra-sonic pulse velocity or dynamic modulus of elasticity and had very high deviation coefficient.
Dynamic modulus of elasticity and compressive strength test methods due to insufficient functional relationship between applied methods and mass losses of cyclic salt-scaling should not be applied for reliable structure analysis of UHPC.
Taking into account, that changes in the microstructure of a material affect such properties as the modulus of elasticity and compressive strength, the change in ultrasonic impulse velocity and the dynamic modulus of elasticity were measured in test specimens subjected to freeze-thaw cycles.
The dynamic modulus of elasticity was measured in concrete prisms (40 x 40 x 160 mm).
The comparison of the changes in ultrasonic pulse velocity and dynamic modulus of elasticity after 200 freeze-thaw cycles in 5% NaCl solution has revealed that the ultrasonic pulse velocity changed from 1.
The same was demonstrated by the lower dynamic modulus of elasticity and ultrasonic pulse velocity.