نوع مقاله : یادداشت فنی
نویسندگان
1
گروه مهندسی عمران، دانشکده مهندسی، دانشگاه کاشان، کاشان، اصفهان، ایران
2
Islamic Azad University, Najafabad Branch
3
Department of Mining and Metallurgical Engineering, Yazd University, Yazd, Iran
10.22034/anm.2026.24629.1731
چکیده
In this study, ultrasonic pulse velocity (UPV) is employed as a non-destructive technique for monitoring damage development in concrete under uniaxial compressive loading. UPV offers a practical means for monitoring the mechanical condition of concrete, because the propagation of ultrasonic waves is strongly affected by microcracking, stiffness degradation, density, and internal discontinuities, without causing additional damage. In this experimental program, a series of sixty 150 mm concrete cube specimens is prepared using a 20 mix design with water–cement ratios of 0.4, 0.5, 0.6, and 0.7, and varying sand-to-gravel ratios. After 28 days of water curing, the specimens are loaded under uniaxial compression until failure, while deformation and ultrasonic transit time are recorded simultaneously. Wave velocity is monitored and analyzed as a function of applied stress and axial strain, together with mix design parameters, initial wave velocity, and compressive strength of the virgin specimens. The results show that ultrasonic velocity decreases progressively with increasing stress, and the reduction becomes much more pronounced when the applied stress approaches approximately one-half of the compressive strength, where microcrack growth accelerates. At ultimate load, the wave velocity drops to nearly half of its initial value. Correlation analysis confirmed a significant inverse relationship between stress/strain and wave velocity, while water–cement ratio, aggregate grading, initial velocity, and maximum strength are also found to influence the response. Based on these findings, this study addresses the existing research gap by experimentally establishing empirical relationships between UPV, stress–strain behavior, and concrete mix design under uniaxial compression, whereas previous studies have mainly focused on strength prediction or qualitative damage evaluation. Based on these observations, empirical equations are derived to estimate stress and strain from UPV measurements, with and without mix-design parameters. The proposed relationships provide a simple and practical framework for assessing stress level, tracking damage progression, and mapping the internal condition of concrete members in engineering structures. This approach may be particularly useful for structural health monitoring and for evaluating the residual load-bearing capacity of concrete elements under service or overload conditions.
کلیدواژهها
موضوعات
عنوان مقاله [English]
Damage assessment of concrete under uniaxial compression using ultrasonic test
نویسندگان [English]
-
Mehdi Sabagh
1
-
Mansour Asgari Khorasgani
2
-
Hosseinali Ghari
3
1
Department of Civil Engineering, Faculty of Engineering, University of Kashan, Kashan, Isfahan, Iran
2
Islamic Azad University, Najafabad Branch
3
Department of Mining and Metallurgical Engineering, Yazd University, Yazd, Iran
چکیده [English]
In this study, ultrasonic pulse velocity (UPV) is employed as a non-destructive technique for monitoring damage development in concrete under uniaxial compressive loading. UPV offers a practical means for monitoring the mechanical condition of concrete, because the propagation of ultrasonic waves is strongly affected by microcracking, stiffness degradation, density, and internal discontinuities, without causing additional damage. In this experimental program, a series of sixty 150 mm concrete cube specimens is prepared using a 20 mix design with water–cement ratios of 0.4, 0.5, 0.6, and 0.7, and varying sand-to-gravel ratios. After 28 days of water curing, the specimens are loaded under uniaxial compression until failure, while deformation and ultrasonic transit time are recorded simultaneously. Wave velocity is monitored and analyzed as a function of applied stress and axial strain, together with mix design parameters, initial wave velocity, and compressive strength of the virgin specimens. The results show that ultrasonic velocity decreases progressively with increasing stress, and the reduction becomes much more pronounced when the applied stress approaches approximately one-half of the compressive strength, where microcrack growth accelerates. At ultimate load, the wave velocity drops to nearly half of its initial value. Correlation analysis confirmed a significant inverse relationship between stress/strain and wave velocity, while water–cement ratio, aggregate grading, initial velocity, and maximum strength are also found to influence the response. Based on these findings, this study addresses the existing research gap by experimentally establishing empirical relationships between UPV, stress–strain behavior, and concrete mix design under uniaxial compression, whereas previous studies have mainly focused on strength prediction or qualitative damage evaluation. Based on these observations, empirical equations are derived to estimate stress and strain from UPV measurements, with and without mix-design parameters. The proposed relationships provide a simple and practical framework for assessing stress level, tracking damage progression, and mapping the internal condition of concrete members in engineering structures. This approach may be particularly useful for structural health monitoring and for evaluating the residual load-bearing capacity of concrete elements under service or overload conditions.
کلیدواژهها [English]
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Damage Assessment
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Non-Destructive Test
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Ultrasonic Waves
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Uniaxial Compression
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Pulse Velocity
)