Experimental study and numerical simulation of impact compression mechanical properties of high strength coral aggregate seawater concrete
Experimental study and numerical simulation of impact compression mechanical properties of high strength coral aggregate seawater concrete
复制标题
高强珊瑚骨料海水混凝土冲击压缩力学性能试验研究及数值模拟
DOI：
10.1016/j.ijimpeng.2019.103466
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发表时间：
2020-03-01
影响因子：
5.1
通讯作者：
Jiang, Xiquan
中科院分区：
文献类型：
--
作者：
Ma, Haiyan;Yue, Chengjun;Jiang, Xiquan
基于高性能轻骨料混凝土配合比设计原则、富浆混凝土理论和纤维增强增韧技术，制备了28d立方抗压强度分别为74.6 MPa和77.3 MPa的高强度珊瑚骨料海水混凝土（CASC）和麻纤维增强CASC （SFCASC）。采用φ 75 mm分离式霍普金森压杆（SHPB）对剑麻纤维含量为3 kg/m(3)的CASC和SFCASC进行冲击压缩试验，并利用LS-DYNA有限元软件对CASC冲击试验进行数值模拟分析。结果表明：高强CASC具有明显的应变率效应，DIF与应变率（(epsilon) / dot）和混凝土抗压强度（f(cu)）有关，欧洲混凝土委员会（CEB）推荐的DIF与应变率关系不适用于高强CASC，在此基础上重新拟合CEB模型参数，建立DIF与应变率的关系；结果表明，冲击入射能、反射能、透射能和吸收能与应变率呈正相关。从能量的角度解释了混凝土的应变率效应，并拟合了DIF与吸收能的关系。当CASC和SFCASC的DIF相同时，SFCASC的吸收能比CASC高49.06% ~ 140.29%；采用LS-DYNA有限元软件模拟应变速率分别为62.3 s（-1）、93.1 s（-1）和137.4 s（-1）的三种工况。得到的应力应变曲线和破坏模式与试验结果吻合较好。通过LS-DYNA数值计算，分析了泊松比随应变速率的变化。发现CASC的泊松比在本文的应变率范围(3 × 10(-6) -1.8 × 10（2) s(-1)）内不存在应变率效应。
Based on the mix proportion design principle of high performance lightweight aggregate concrete, rich slurry concrete theory and fiber reinforced toughening technology, high strength Coral Aggregate Seawater Concrete (CASC) and sisal fiber reinforced CASC (SFCASC) with 28d cube compressive strength of 74.6 MPa and 77.3 MPa respectively were prepared. The Phi 75 mm split Hopkinson pressure bar (SHPB) was used to carry out impact compression tests on CASC and SFCASC with sisal fiber content of 3 kg/m(3), and the finite element software LS-DYNA was used to carry out numerical simulation analysis on CASC impact tests. The results show that high strength CASC has obvious strain rate effect, DIF is related to strain rate ((epsilon)over dot) and concrete compressive strength (f(cu)), the relationship between DIF and strain rate recommended by the European Concrete Committee (CEB) is not applicable to high-strength CASC, the parameters of CEB model are re-fitted and the relationship between DIF and strain rate is established on the basis of the above (epsilon)over dot and f(cu); It is found that impact incident energy, reflection energy, transmission energy and absorption energy are positively correlated with strain rate. The strain rate effect of concrete is explained from the angle of energy, and the relation between DIF and absorption energy is fitted. When the DIF of CASC and SFCASC are the same, the absorption energy of SFCASC is 49.06%-140.29% higher than that of CASC; The finite element software LS-DYNA is used to simulate three working conditions with strain rates of 62.3 s(-1), 93.1 s(-1) and 137.4 s(-1). The stress-strain curves and failure patterns obtained are in good agreement with the experimental results. The change of Poisson's ratio with strain rate is analyzed according to LS-DYNA numerical calculation. It is found that Poisson's ratio of CASC has no strain rate effect within the strain rate range of this paper (3 x 10(-6) -1.8 x 10(2) s(-1)).