In this paper, the effect of polyolefin macro fibers on fracture, fresh and hardened state properties of self-compacting lightweight concrete (SCLC) has been assessed. To do so, four SCLC mixes have been cast such that the solid contents and water to binder ratio have been kept constant while the volume fraction of fiber contents varied from 0.0% to 0.5% by concrete volume. Moreover, to evaluate the effect of size on fracture parameters and nominal strength of the beams, three different sizes of specimens were considered such that they have been kept geometrically similar. The experimental results showed that the fiber contents have negligible effects on mechanical properties of SCLC. However, the post peak behavior of the specimen was affected by the amount of fiber contents. The so-called universal size-shape effect law was adopted successfully to indicate the effects regarding the size of the specimens on their nominal strength. Besides, the fracture energy and fracture toughness of the mixes showed almost no size dependency, especially for characteristic dimensions higher than 100 mm.

在本文中，评估了聚烯烃大纤维对自密实轻质混凝土（SCLC）的断裂，新鲜和硬化状态性能的影响。为此，已经浇铸了四种SCLC混合物，以使固含量和水与粘结剂的比例保持恒定，而纤维含量的体积分数从混凝土体积的0.0％变为0.5％。而且，为了评估尺寸对梁的断裂参数和标称强度的影响，考虑了三种不同尺寸的样本，以使它们在几何上保持相似。实验结果表明，纤维含量对SCLC的力学性能影响可忽略不计。但是，样品的峰后行为受纤维含量的影响。成功地采用了所谓的通用尺寸形状效应定律，以表明有关试样尺寸对其标称强度的影响。此外，混合物的断裂能和断裂韧性几乎没有大小相关性，特别是对于大于100 mm的特征尺寸。