改性无砂混凝土路用性能研究

提高无砂混凝土的强度和疲劳寿命是其应用的关键,而改性剂往往能起到良好效果。一种新型聚合物外加剂作为改性剂被掺加到无砂混凝土中,首先通过微观分析和水泥胶浆标准试验,确定了外加剂合适的用量,然后与普通无砂混凝土以及同水泥用量、同强度等级的两种普通混凝土进行强度、收缩以及疲劳试验对比,试验表明该改性剂能较大幅度提高无砂混凝土强度,达到规范混凝土面层强度要求,同时具备良好的收缩性能,特别是拥有优异的抗疲劳性能,使其达到甚至超出了混凝土面层的使用要求。

Study on Performance of Modified No-fines Concrete

The key of no-fines concrete's application is how to improve its strength and fatigue performance,and usually additive can take good effect.As modifier,a new polymer additive was added to no-fines concrete.First,right dosage of additive was confirmed by microcosmic analysis and cement slurry test.Then,strength,shrinkage and fatigue performance of the modified no-fines concrete were compared with those of common no-fines concrete and two kinds of common concrete with same cement dosage and same intensity grade through tests.The result shows that(1) this modifying additive can improve the performance of no-fines concrete evidently to make the strength of surface course meet the requirement of related criterion;(2) it has good shrinkage performance and especially excellent anti-fatigue performance,which make it meets or surpasses the application requirement of surface course.