Hou Weiye, Hu Yuyang, Yuan Chengfang, Feng Hu, Cheng Zhanqi
School of Applied Science and Technology, Hainan University, Danzhou 570216, China.
School of Civil Engineering, Zhengzhou University, Zhengzhou 450001, China.
Materials (Basel). 2022 May 12;15(10):3494. doi: 10.3390/ma15103494.
The mechanical properties of engineered cementitious composites (ECC) are time-dependent due to the cement hydration process. The mechanical behavior of ECC is not only related to the matrix material properties, but also to the fiber/matrix interface properties. In this study, the modeling of fiber and fiber/matrix interactions is accomplished by using a semi-discrete model in the framework of peridynamics (PD), and the time-varying laws of cement matrix and fiber/matrix interface bonding properties with curing age are also considered. The strain-softening behavior of the cement matrix is represented by introducing a correction factor to modify the pairwise force function in PD theory. The fracture damage of ECC plate from 3 to 28 days was numerically simulated by using the improved PD model to visualize the process of damage fracture under dynamic loading. The shorter the hydration time, the lower the corresponding elastic modulus, and the smaller the number of cracks generated. The dynamic fracture process of early-age ECC is analyzed to understand the crack development pattern, which provides reference for guiding structural design and engineering practice.
由于水泥水化过程，工程水泥基复合材料（ECC）的力学性能具有时间依赖性。ECC的力学行为不仅与基体材料性能有关，还与纤维/基体界面性能有关。在本研究中，通过在非局部连续介质力学（PD）框架下使用半离散模型来实现纤维与纤维/基体相互作用的建模，并且还考虑了水泥基体和纤维/基体界面粘结性能随养护龄期的时变规律。通过引入修正因子来修改PD理论中的成对力函数，以表征水泥基体的应变软化行为。利用改进的PD模型对3至28天龄期的ECC板的断裂损伤进行了数值模拟，以可视化动态加载下的损伤断裂过程。水化时间越短，相应的弹性模量越低，产生的裂纹数量越少。分析了早期ECC的动态断裂过程，以了解裂纹发展模式，为指导结构设计和工程实践提供参考。
