Guo Menghui, He Yongsheng, Zhi Xudong
Key Lab of Structures Dynamic Behaviour and Control of the Ministry of Education, Harbin Institute of Technology, Harbin 150090, China.
Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters of the Ministry of Industry and Information Technology, Harbin Institute of Technology, Harbin 150090, China.
Materials (Basel). 2024 Sep 28;17(19):4781. doi: 10.3390/ma17194781.
Foamed concrete is increasingly utilized in protection engineering because it offers a high energy absorption ratio and a relatively low construction cost. To investigate the dynamic properties of foamed concrete, a series of dynamic compression tests are carried out on high-density foamed concrete with densities of 800 kg/m, 1000 kg/m, and 1100 kg/m under a strain rate range of 59.05 s~302.17 s by using a Φ-100 mm split Hopkinson pressure bar (SHPB) device. The effects of strain rate on the stress-strain relationship, dynamic compressive strength, and dynamic increase factor of foamed concrete are discussed in detail. The results show that the dynamic mechanical characteristics of foamed concrete with different densities exhibit a significant strain rate enhancement effect. Additionally, the energy absorption characteristics of foamed concrete are investigated, demonstrating that it can effectively prevent the transmission of incident energy and that its energy absorption efficiency declines as the strain rate increases. A high-speed camera was also employed to capture the failure process of foamed concrete. The results exhibit that fracture production and development induce the failure of foamed concrete, the failure process of foamed concrete advances as the strain rate increases, and the failure mode becomes increasingly severe.
泡沫混凝土因其具有高能量吸收率和相对较低的施工成本,在防护工程中得到越来越广泛的应用。为研究泡沫混凝土的动态性能,采用直径100mm的分离式霍普金森压杆(SHPB)装置,对密度分别为800kg/m³、1000kg/m³和1100kg/m³的高密度泡沫混凝土在59.05s⁻¹~302.17s⁻¹的应变率范围内进行了一系列动态压缩试验。详细讨论了应变率对泡沫混凝土应力-应变关系、动态抗压强度和动态增强因子的影响。结果表明,不同密度的泡沫混凝土的动态力学特性均表现出显著的应变率增强效应。此外,还对泡沫混凝土的能量吸收特性进行了研究,结果表明它能有效阻止入射能量的传播,且其能量吸收效率随应变率的增加而降低。还使用高速摄像机捕捉了泡沫混凝土的破坏过程。结果表明,裂缝的产生和发展导致了泡沫混凝土的破坏,泡沫混凝土的破坏过程随应变率的增加而推进,破坏模式也越来越严重。