Lin Yanling, Ren Yuzhe, Ge Tiange, Al-Ajamee Mohammed, Xu Yinglei, Mohamed Abubaker Ahmed Mohamed Salih, Ma Lu, Zhang Hongxu
School of Construction Engineering, Jiangsu Open University, No.399 North Jiangdong Road, Nanjing, China.
Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering, Hohai University, No.1 Xikang Road, Nanjing, China.
Sci Rep. 2024 Aug 27;14(1):19800. doi: 10.1038/s41598-024-70505-4.
Waste oyster shells (WOS) have the potential to serve as a construction material, offering a sustainable alternative to traditional fine aggregates in the production of WOS concrete. This can play a critical role in reducing environmental issues resulting from the overexploitation of river sand and the haphazard disposal of WOS. Although existing research has predominantly focused on understanding the static mechanical characteristics of concrete when WOS is employed, the dynamic mechanical properties have still received less attention. To understand the impact of WOS as a substitute for fine aggregates on the dynamic mechanical properties of concrete, a series of tests employing Split Hopkinson Pressure Bar (SHPB) were carried out. The findings demonstrate that the peak stress and elastic modulus increase as the WOS substitution ratio (S) increases from 0 to 20% but exhibit an exponential decline as S increases from 20 to 100%. This response can be explained by the joint effects of the pore-filling effect caused by WOS sand and the increasing air content caused by WOS sand. As S increases from 0 to 20%, the pore-filling mechanism becomes predominant as the water absorption rate decreases slightly from 4.31 to 3.83%. However, for S increasing from 20 to 100%, the negative influence of the air content becomes the primary contributing factor, where the water absorption rate increases from 3.83 to 14.68%. Furthermore, under the same impact pressure, the concrete with S = 20% absorbed the most energy, providing the best dynamic mechanical performance. These findings highlight the potential use of WOS in concrete for improving its dynamic characteristics, promoting both sustainable construction and enhancing the material properties in impact-resistant structures.
废弃牡蛎壳（WOS）有潜力用作建筑材料，在WOS混凝土生产中为传统细集料提供可持续的替代方案。这对于减少因过度开采河砂和随意处置WOS而产生的环境问题可发挥关键作用。尽管现有研究主要集中于了解使用WOS时混凝土的静态力学特性，但动态力学性能仍较少受到关注。为了解WOS替代细集料对混凝土动态力学性能的影响，进行了一系列采用分离式霍普金森压杆（SHPB）的试验。研究结果表明，随着WOS替代率（S）从0增加到20%，峰值应力和弹性模量增加，但当S从20%增加到100%时呈指数下降。这种响应可以通过WOS砂引起的孔隙填充效应和WOS砂导致的含气量增加的共同作用来解释。当S从0增加到20%时，随着吸水率从4.31%略微降至3.83%，孔隙填充机制占主导地位。然而，当S从20%增加到100%时，含气量的负面影响成为主要因素，此时吸水率从3.83%增加到14.68%。此外，在相同冲击压力下，S = 20%的混凝土吸收能量最多，具有最佳的动态力学性能。这些发现突出了WOS在混凝土中用于改善其动态特性的潜在用途，既促进了可持续建筑，又提高了抗冲击结构中的材料性能。
