DECivil/ICIST, Instituto Superior Técnico, Technical University of Lisbon, Av. Rovisco Pais, Lisbon, Portugal.
Ultrasonics. 2013 Jul;53(5):962-72. doi: 10.1016/j.ultras.2012.12.012. Epub 2013 Jan 3.
In this paper the compressive strength of a wide range of structural lightweight aggregate concrete mixes is evaluated by the non-destructive ultrasonic pulse velocity method. This study involves about 84 different compositions tested between 3 and 180 days for compressive strengths ranging from about 30 to 80 MPa. The influence of several factors on the relation between the ultrasonic pulse velocity and compressive strength is examined. These factors include the cement type and content, amount of water, type of admixture, initial wetting conditions, type and volume of aggregate and the partial replacement of normal weight coarse and fine aggregates by lightweight aggregates. It is found that lightweight and normal weight concretes are affected differently by mix design parameters. In addition, the prediction of the concrete's compressive strength by means of the non-destructive ultrasonic pulse velocity test is studied. Based on the dependence of the ultrasonic pulse velocity on the density and elasticity of concrete, a simplified expression is proposed to estimate the compressive strength, regardless the type of concrete and its composition. More than 200 results for different types of aggregates and concrete compositions were analyzed and high correlation coefficients were obtained.
本文采用无损超声脉冲速度法评估了一系列结构轻骨料混凝土混合物的抗压强度。这项研究涉及约 84 种不同的配合比，测试时间为 3 至 180 天，抗压强度范围约为 30 至 80MPa。研究了多种因素对超声脉冲速度与抗压强度之间关系的影响。这些因素包括水泥类型和含量、用水量、外加剂种类、初始润湿条件、骨料类型和体积以及普通骨料和轻骨料的部分替代。结果发现，轻骨料混凝土和普通骨料混凝土受配合比参数的影响不同。此外，还研究了通过无损超声脉冲速度测试来预测混凝土抗压强度。基于超声脉冲速度对混凝土密度和弹性的依赖性，提出了一种简化表达式，可估算抗压强度，而无需考虑混凝土的类型及其组成。分析了超过 200 种不同类型的骨料和混凝土组成的结果，得到了较高的相关系数。
