Mesoscale modelling of concrete reinforced with spiral steel fibres under dynamic splitting tension
Mesoscale modelling of concrete reinforced with spiral steel fibres under dynamic splitting tension
复制标题
动态劈裂张力下螺旋钢纤维增强混凝土的细观建模
DOI：
10.1177/1369433217734654
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发表时间：
2018
影响因子：
2.6
通讯作者：
Hao Hong
中科院分区：
文献类型：
--
作者：
Hao Yifei;Huang Xin;Hao Hong
在混凝土中掺入离散钢纤维是提高混凝土延性、抗裂性和抗冲击能量吸收的有效措施。尽管钢纤维增强混凝土在动态荷载作用下的宏观性能的实验研究提供了有用的信息，但一系列试验或不同研究人员的试验结果往往是分散的。除了试验条件的变化外，钢纤维混凝土中骨料和纤维的尺寸、位置和取向的随机变化是造成试验数据分散的根本原因。混凝土和钢纤维增强混凝土的细观高保真建模已被广泛采用，以了解复合材料中各组分的影响。数值研究已经出版，以讨论钢纤维混凝土在动态劈拉下的行为。不同的研究考虑了圆形、椭圆形和多边形等不同形状的粗集料，得出了不同的结论。本文研究了骨料形状对动态劈裂拉伸条件下钢纤维混凝土材料细观数值模拟中应变分布、开裂模式和强度的影响。实验结果验证了数值模型的正确性。研究发现，骨料的形状在劈裂拉伸试验的细观模拟中的影响可以忽略不计。此外，在不同的加载速率下，不同的螺旋纤维体积分数从0.5%到3.0%的钢纤维混凝土试件进行了模拟。参数模拟结果表明，螺旋纤维在钢纤维混凝土配合比中的最佳剂量相对于施工成本和力学性能控制。
The addition of discrete steel fibres into concrete has been widely recognised as an effective measure to enhance the ductility, post-cracking resistance and energy absorption of the matrix subjected to impact loads. Despite useful information from experimental studies that investigate the macro-scale performance of steel fibre–reinforced concrete under dynamically applied loadings, results from a series of tests or from tests by different researchers are often found to be scattered. Besides variations in testing conditions, random variations of size, location and orientation of aggregates and fibres in steel fibre–reinforced concrete are deemed the fundamental reason of the scattering test data. High-fidelity modelling of concrete and steel fibre–reinforced concrete in mesoscale has been widely adopted to understand the influence of each component in the composite material. Numerical studies have been published to discuss the behaviour of steel fibre–reinforced concrete under dynamic splitting tension. Different shapes, for example, circles, ovals and polygons, of coarse aggregates were considered in different studies, and different conclusions were drawn. This study investigates the influence of the shape of aggregates on numerical prediction in mesoscale modelling of steel fibre–reinforced concrete materials with spiral fibres under dynamic splitting tension in terms of the strain distribution, cracking pattern and strength. The numerical model is validated by experimental results. It is found that the shape of aggregates in mesoscale modelling of splitting tensile tests has negligible influence. Furthermore, steel fibre–reinforced concrete specimens with different volume fractions of spiral fibres from 0.5% to 3.0% under various loading rates are simulated. Results from parametric simulations indicate the optimal dosage of spiral fibres in steel fibre–reinforced concrete mix with respect to the construction cost and mechanical property control.