Study On Monitoring Frost Resistance Of Concrete Structure Based On Impact Elastic Wave Method

Impact elastic wave technology can detect P wave velocity,and by using the mathematical relationship between P wave velocity and dynamic elastic modulus,it can reflect the frost resistance of concrete and evaluate the durability of structure.In this paper,the feasibility of testing the frost resistance of concrete with impact elastic wave technology is studied firstly,and then the reliability of testing with impact elastic wave technology is explored.Finally,the evaluation method of testing the durability of hydraulic concrete structure with impact elastic wave in situ is put forward.The main research contents and achievements are as follows:(1)By comparing with resonance method,ultrasonic method and impact echo method,the feasibility of testing dynamic elastic modulus and evaluating frost resistance by impact elastic wave technology is studied.The results show that both ultrasonic technology and impact elastic wave technology can effectively measure the dynamic elastic modulus and evaluate the frost resistance of concrete structures,but the impact echo method and resonance method have better fitting degree,and the evaluation results of impact elastic wave will be more accurate combined with the actual testing process.(2)The reliability of impact elastic wave technology is explored through repeatability test and reproducibility test.The research results show that,as a nondestructive testing technology,the impact elastic wave technology has good reliability in evaluating the frost resistance of concrete structures.(3)Combined with a specific project,the feasibility of introducing impact elastic wave method into the existing evaluation method of frost resistance of concrete in site is verified,and the evaluation method of impact elastic wave on durability of hydraulic concrete structure in site is put forward.