| 摘要: |
| 以矿渣、粉煤灰为原材料，NaOH，Na2CO3为碱激发剂，制备了强度等级为C30的高流态地质聚合物混凝土（highly fluidized geopolymer concrete, HFGC）, 并采用经波形整形技术改进后的100分离式霍普金森压杆（SHPB）试验装置测试了HFGC在冲击荷载下的强度特性,包括动态劈裂拉伸强度和动态压缩强度.结果表明：HFGC的动态强度特性表现出了明显的应变率相关性，其增强因子可用平均应变率的对数线性表示；动态劈裂拉伸状态下的应变率敏感阀值为5.027s-1，动态压缩状态下的应变率敏感阀值为28.89s-1，动态劈裂拉伸强度的应变率敏感性要比动态压缩强度强；HFGC的动态强度特性的定性趋势与普通混凝土一致，但与普通混凝土相比，HFGC的应变率敏感性因其具备特有的无机缩聚三维氧化物网络结构而更为明显，可以更有效地发挥其在冲击荷载作用下的整体强度特性.由此可见，HFGC是应变率敏感材料. |
| 关键词: 高流态地质聚合物混凝土 分离式霍普金森压杆 动态劈裂拉伸试验 动态压缩试验 强度特性 波形整形技术 |
| DOI：103969/j.issn1007 9629201401013 |
| 分类号: |
| 基金项目:国家自然科学基金资助项目（51208507，51378497）；陕西省自然科学基金资助项目（2011gm6014） |
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| Strength Properties of Highly Fluidized GeopolymerConcrete under Impact Loading |
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LUO Xin1, XU Jinyu1, SU Haoyang1, BAI Erlei1, LI Weimin2
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1.Department of Airfield and Building Engineering, Air Force Engineering University, Xian 710038, China;2.Airport Office, Air Force Logistics Department in Guangzhou Military Region, Guangzhou 510052, China
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| Abstract: |
| C30 highly fluidized geopolymer concrete（HFGC） was prepared by using slag and fly ash as raw materials and NaOH and Na2CO3 as alkaline activation agent. The strength properties of HFGC under impact loading, including dynamic splitting tensile and compressive strength, were studied by using 100 split Hopkinson pressure bar(SHPB) apparatus improved with the pulse shaper technique. The results indicate that dynamic strength properties of HFGC exhibit strong strain rate dependence; for HFGC, strain rate sensitivity threshold under dynamic splitting tensile condition is 5.027s-1, and under dynamic compressive condition that is 28.89s-1, the strain rate sensitivity of dynamic splitting tensile strength is higher than that of dynamic compressive strength; the qualitative trend of dynamic strength properties of HFGC are in accord with that of normal concrete, but compared with normal concrete, the strain rate sensitivity of HFGC becomes even higher because of polycondensed network structure, and that can effectively develop the overall strength properties under impact loading. Thus it can be seen that HFGC is strain rate sensitive. |
| Key words: highly fluidized geopolymer concrete（HFGC） split Hopkinson pressure bar（SHPB） dynamic splitting tensile test dynamic compressive test strength property pulse shaping technique |
