Evaluation of the concrete strength using IE and SASW methods
Recently,the strength estimation of concrete is getting more important for existing structures.Wave velocity based nondestructive methods are very attractive because of simple configuration.The Ultrasonic Pulse Velocity(UPV)method has been widely used for evaluating the strength of civil structures because it is non-intrusive and simple in the field.UPV estimates the concrete strength using the wave propagation velocity calculated by direct travel time method,but it is hard to get the exact velocity.Impact Echo(IE)is a non-destructive test for obtaining wave velocity on concrete structure using the velocity by resonance.Spectral Analysis of Surface Wave(SASW)method which is also non-intrusive was used for determining surface wave velocity of concrete structure.In this paper,the feasibility of IE and SASW methods for the strength estimation was studied.Both IE and SASW methods were performed on four walltype structures of concrete having different strengths.UPV methods were also performed at the same testing points to compare with IE values.The uniaxial compression tests were performed to measure concrete strength exactly using cores from all testing points.In the IE method,P-wave velocity was determined in the frequency domain with the known wall thickness.In the SASW method,dispersion curve which is the relation between phase velocity and wave length is first determined.Then the representative average surface wave velocity was found using a sequence of statistical mathematic operations and P-wave velocity is derived using the Poissons ratio of concrete structure.The P-wave velocities obtained by IE and SASW methods match well.The relation between the P-wave velocity from IE and SASW methods and concrete strength was proposed and compared with existing empirical relationships.From the observations,IE and SASW methods show the feasibility to estimate the concrete strength.
Nondestructive Impact Echo SASW concrete strength P-wave Surface wave
D.S., Kim S.W., Jin E.S., Bang
Department of Civil and Environmental Engineering,KAIST,Daejeon,South Korea Geotechnical Engineering Division,KIGAM,Daejeon,South Korea
国际会议
The World Forum on Smart Materials and Smart Structures Technology(SMSST07)(2007年世界智能材料与智能结构技术论坛)
重庆·南京
英文
2007-05-01（万方平台首次上网日期，不代表论文的发表时间）