非金属声屏障单元板的轻质优化及力学研究

非金属声屏障因其良好的吸隔声性能、力学性能、耐候性能以及耐久性能迅速成为高速铁路降噪工程中的首选产品。针对非金属声屏障的制作工艺及力学性能,通过总结对比提出优化方案,使用轻质混凝土作为主要材料,将非金属声屏障单位面积内的重量极大降低,并通过有限元软件ANSYS14.5进行改良后产品的力学性能模拟分析,对其在极端情况下的可行性进行验证。     

Freeze-thaw Durability of Recycled Aggregate Concrete:An Overview

The characteristics of surface appearances,mass loss,relative dynamic modulus of elasticity and strength loss of different recycled aggregate concretes(RAC) exposed to freeze-thaw cycles were analyzed.It was found that the freeze-thaw resistance of RAC could be determined by the recycled aggregate compositions and admixtures.Both the saturation degree and the air void structure were the key factors influencing the freeze-thaw damage on concrete.Some major proposed freeze-thaw deterioration mechanisms were utilized to interpret the freeze-thaw damage on recycled aggregate concrete.Meanwhile,some potential measures to enhance the freeze-thaw resistance of concrete were summarized and discussed.