粗骨料级配对普通和高强度等级机制砂混凝土性能的影响

粗骨料对混凝土的工作性能、力学性能和耐久性具有很大影响,因此,选择粗骨料级配非常重要。本文将三种粒度粗骨料按不同比例进行混合,研究了粗骨料级配对普通和高强度等级机制砂混凝土的性能影响。结果表明:三级配粗骨料制备的普通强度等级混凝土的强度最高;对高强度等级混凝土而言,两级配粗骨料制备的混凝土强度最高。粗骨料比表面积对普通强度等级混凝土性能影响较大,而粗骨料堆积空隙率对高强度等级混凝土性能影响较大。

Effect of Content and Particle Size Distribution of Coarse Aggregate on the Properties of Normal and High Strength Concrete

Coarse aggregate fraction is known to strongly influence both fresh and hardened properties of concretes.Therefore,selection of particle size distribution(PSD) of aggregate for concrete mixture is an important issue.In the present study,three aggregate fractions were combined in different proportions to investigate the effect of the PSD of aggregate on the properties of concrete.Results show that normal strength concretes made with a ternary combination of aggregate fractions have the highest compressive strength.However,for high strength concretes,binary aggregate system leads to the highest compressive strength.The surface of aggregate has major influence on the properties of normal strength concretes,while the properties of high strength concretes significantly related to packing of aggregate.