Department of Mining Eng., Karadeniz Technical University, 61080 Trabzon, Turkey.
Ultrasonics. 2014 Jan;54(1):195-204. doi: 10.1016/j.ultras.2013.04.013. Epub 2013 Apr 27.
This paper presents the strength (UCS) and ultrasonic pulse velocity (UPV) properties of cemented paste backfill (CPB) produced from two different mill tailings (Tailings T1 and T2). A total of 240 CPB samples with diameter×height of 5 × 10 cm and 10 × 20 cm prepared at different binder dosages (5-7 wt.%) and water-to-cement ratios (3.97-5.10) were subjected to the UPV and UCS tests at 7, 14, 28 and 56-days of curing periods. UCS and UPV of CPB samples increased with increasing the binder dosage and reducing the w/c ratio irrespective of the sample size and tailings type. CPB samples with a diameter × height of 5 × 10 cm were observed to produce consistently higher (up to 1.69-fold) UCSs than those of 10 × 20 cm CPB samples at all binder dosages and w/c ratios. However, at the corresponding binder dosages and w/c ratios, the maximum variation of UPV between the CPB samples of 5 × 10 cm and 10 × 20 cm was only 7.45%. Using the method of least squares regression, the UCS values were correlated with the UPV values for CPB samples of 10 × 20 cm in size. A linear relation with a high correlation coefficient appeared to exist between the UCS and UPV for CPB samples. These findings suggest that the UPV is essentially independent of the sample size. In this regard, the UPV test can be suitably exploited for the rapid estimation of the strength and quality of CPB samples even using small samples with concomitant benefits of reducing sample size.
本文介绍了由两种不同的尾矿（尾矿 T1 和 T2）制成的胶结充填料浆（CPB）的强度（UCS）和超声波脉冲速度（UPV）特性。共制备了 240 个直径×高度为 5×10cm 和 10×20cm 的 CPB 样品，在不同的胶结剂量（5-7wt.%）和水胶比（3.97-5.10）下，在养护期的 7、14、28 和 56 天进行了 UPV 和 UCS 测试。无论样品尺寸和尾矿类型如何，CPB 样品的 UCS 和 UPV 均随胶结剂量的增加和水胶比的降低而增加。所有胶结剂量和水胶比下，直径×高度为 5×10cm 的 CPB 样品的 UCS 始终高于 10×20cm CPB 样品（高达 1.69 倍）。然而，在相应的胶结剂量和水胶比下，5×10cm 和 10×20cm CPB 样品之间的 UPV 最大变化仅为 7.45%。使用最小二乘法回归方法，将 UCS 值与尺寸为 10×20cm 的 CPB 样品的 UPV 值相关联。对于 CPB 样品，UCS 和 UPV 之间似乎存在线性关系，且相关系数较高。这些发现表明 UPV 基本上与样品尺寸无关。在这方面，即使使用小样本，也可以适当地利用 UPV 测试来快速估计 CPB 样品的强度和质量，同时还可以减少样本数量。
