Evaluating residual compressive strength of concrete at elevated temperatures using ultrasonic pulse velocity

Analysis of Factors Influencing Fire Damage to Concrete Using Nonlinear Resonance Vibration Method

“…이를 이용하여 화재 손상 콘크리트에 적용한 대표적인 기법으로는 초 음파속도측정법(ultrasonic wave velocity method) [7], 충격반향기법(impact-echo method) [ …”

Evaluation of Fire-Damaged Concrete: An Experimental Analysis based on Destructive and Nondestructive Methods

“…These methods can be divided into two categories depending on the measurement techniques and target defects: linear and nonlinear ultrasonic methods. Linear ultrasonic methods, which measure wave velocity, wave attenuation, and impact echo, are conventional ultrasonic methods and have been widely used to evaluate damaged concrete, particularly firedamaged concrete (Chaix et al 2003;Colombo and Felicetti 2007;Dilek and Leming 2007;Epasto et al 2010;Kee and Nam 2015;Yang et al 2009). However, these linear methods exhibit lower sensitivity to distributed defects and contacttype defects at the micro-scale (Jhang 2009;Park et al 2015) compared to nonlinear ultrasonic methods, which are more sensitive to early-stage micro-scale defects as these defects cause nonlinear behavior of an incident wave (Zaitsev et al 2006).…”

A non-destructive technique for health assessment of fire-damaged concrete elements using terrestrial laser scanning

“…According to Ergün et al [4] one of most damaging environmental effects for concrete structures is exposure to elevated temperatures and concrete structures such as bridges, viaducts, tunnels, buildings and parking garages are examples of structures at risk of fire damage [5]. Even though concrete is known to be a material with high fire resistance and capable of retaining much of its load-bearing capacity, it undergoes severe modifications in its physical, chemical and mechanical properties when subjected to high temperatures [6].…”

“…The first and most cardinal task for structural safety appraisal of a concrete structure that has been subjected to fire is damage assessment [6]. A damage assessment in such a case aims at providing the relevant information needed to evaluate the residual bearing capacity and durability of the fire-damaged structure and to propose appropriate repair methods or to decide if demolition is more appropriate [7].…”

“…Normally, a damage classification chart for the elements involved in a fire is prepared as an output from the assessment process and such a chart can be used in the selection of appropriate repair techniques [8,10]. Within the field of civil engineering, various studies have been conducted aimed at investigating the effects of heating rate, elevated temperature exposure and the exposure duration on the residual strength of concrete [6,11,12]. It has been reported that when concrete is heated between 200°C and 250°C it begins to undergo loss in its compressive strength.…”