سال انتشار: ۱۳۸۸
محل انتشار: نخستین کنفرانس بین المللی تکنولوژی بتن
تعداد صفحات: ۱۲
Asaad Ahmed Elshab – Al-Fetah University, Faculty of Engineering / 7th of October University, Faculty of Engineering
Naje Emhemed Saleh – Al-Fetah University, Faculty of Engineering / 7th of October University, Faculty of Engineering
The ultrasonic pulse velocity (UPV) of range of high strength concrete (HSC) ranging from 50-120 N/mm2 was measured to assess concrete quality. Crushed limestone and gravel aggregates of 10mm single size and sintered fly ash of high porosity were used. A 100mm cubes and Prisms (275 x 76 x 76 mm), were used as test specimen after they were initially water cured or air dried for 7 days then oven dried at 105°C or at 50°C then 105°C. The influence of mix composition, curing regime, drying temperature, incorporation of 10% condensed silica fume (csf), and effect of cracking resulting from the applied loads were investigated. The cubes were subjected to different levels of compressive stress/strength ratio loading (0.3, 0.6, 0.9) for 4 times, while the concrete prisms were subjected to different levels of torsional stress/strength ratio loading (0.6, 0.9) for 4 times, then used to measure the ultrasonic pulse velocity. The ultrasonic pulse velocity was found to give a good indication of the concrete quality and reflected the changes which occurred in the concrete microstructure due to the change in mix composition, curing regime, moisture content or damage. The ultrasonic pulse velocity was found to correlate with the concrete compressive strength and torsional strength values.