Dynamic splitting-tensile strength and energy dissipation property of EPS concrete
-
摘要: 用分离式Hopkinson压杆对多种聚苯乙烯(expanded polystyrene,EPS)体积含量的EPS混凝土试样进行了动态劈裂实验。提出了描述EPS混凝土劈裂强度与应力率关系的经验公式,该式同时适合于静态和动态应力率,并根据实验结果拟合了系数。分析了EPS含量、粒径大小对劈裂强度和动态增强因数的影响,发现碳纤维能有效提高EPS混凝土的动态劈裂强度,尤其对于小EPS粒径混凝土。此外,还研究了试样的能量耗散随应力率的变化规律,EPS含量增加时,试样的能量耗散随应力率的增加而增加,反应出EPS颗粒具有增韧和吸能效果。Abstract: Dynamic splitting tests were carried out by using a split Hopkinson pressure bar (SHPB) for the expanded polystyrene (EPS) concrete with the different volume fractions of EPS. An empirical formula was proposed to describe the relationship between the splitting strength and the stress rate of the EPS concrete. And the proposed empirical formula can be suitable for both static and dynamic stress rates. Based on the experimental results,the parameters for the formula were fitted. The influences of the volume fraction and the bead size of EPS on the splitting strength and the dynamic increase factor of the EPS concrete were analyzed. The experimental results show that carbon fibers have obvious reinforcing effect on dynamic splitting strength,especially for the concretes with the small bead sizes of EPS. The effects of the stress rates on the dissipated energies of the specimens were discussed. It can be found that the dissipated energies of the specimens increase with the increase of the stress rates in the case of increasing the EPS volume fractions in the concrete specimens. So the EPS beads can toughen the concrete specimens and improve their energyabsorbing performances.
-
Key words:
- solid mechanics /
- splitting strength /
- dynamic increase factor /
- EPS concrete /
- energy dissipation /
- stress rate
点击查看大图
计量
- 文章访问数: 2786
- HTML全文浏览量: 150
- PDF下载量: 177
- 被引次数: 0