冲击荷载作用下掺橡胶颗粒自密实混凝土的力学性能  

Mechanical Properties of Self-Compacting Concrete Incorporating Rubber Particles under Impact Load

作　　者：龙广成[1] 李宁[1] 薛逸骅 谢友均[1] 

机构地区：[1]中南大学土木工程学院,长沙410075

出　　处：《硅酸盐学报》2016年第8期1081-1090,共10页Journal of The Chinese Ceramic Society

基　　金：973计划课题高速铁路基础结构关键工程材料动态性能劣化行为(2013CB036201);国家自然科学基金自密实橡胶混凝土的微细观结构与力学机制(51178467)

摘　　要：为探究掺橡胶颗粒自密实混凝土(SCC)在冲击荷载下的力学特性,采用?75 mm分离式霍普金森压杆(SHPB)试验方法,对比分析了不同橡胶颗粒掺量SCC的冲击压缩破坏模式及其应力–应变关系,并基于应变等价性假说和统计损伤理论建立了其动态力学本构模型。结果表明:橡胶颗粒的掺入增强了SCC抵抗不同应变率条件下的破坏作用;SCC的动态强度增长因子DIF随应变率的增加而显著增大,且随橡胶掺量的增加,DIF的增长率提高;在应变率相同时,橡胶颗粒对SCC动态强度的增强效果大于普通混凝土;掺橡胶颗粒SCC弹性模量的应变率相关性不明显,但在所调查的应变率范围内,SCC弹性模量有一定的增加,橡胶掺量为0、10%、20%和30%时,其各自的平均弹性模量比静态弹性模量分别提高了35.1%、39.7%、53.3%和57.7%;所建立的本构模型与试验结果吻合较好。In order to clarify the influence of rubber particles on the performance of self-compacting concrete （SCC） at an impact load, the dynamic impact compression properties of SCC with rubber particles were investigated by a split Hopkinson pressure bar （SHPB） method, and the corresponding dynamic constitutive model was established based on strain equivalence hypothesis and statistical damage theory. The results show that rubber particles can enhance the ability to resist damage of SCC at different strain rates. The dynamic increase factor （DIF） of SCC increases with increasing strain rate, and the growth rate of DIF increases with increasing rubber particles volume. The strength increment of SCC with rubber particles is greater than that of normal concrete with rubber particles at the similar strain rates. There is no obvious correlation between elastic modulus of SCC incorporating rubber particles and strain rates investigated in this paper although the elastic modulus of SCC shows a little bit increase; The average elastic modulus of SCC with 0, 10%, 20% and 30% rubber replacement are 35.1%, 39.7%, 53.3% and 57.7% higher than that of static elastic modulus, respectively. The calculated data by the established dynamic constitutive model are similar to the experimental results.

关 键 词：自密实混凝土 冲击 橡胶颗粒 本构模型 分离式霍普金森压杆试验 

分 类 号：TU528.53[建筑科学—建筑技术科学]