The development of an elasto-plastic phase-field model is presented which is able to predict nonlinear behavior of high performance concrete (HPC) during low-cycle fatigue. An elasto-plastic damage model which follows the Drucker–Prager yield criterion is formulated. For the modeling of unsymmetric tension–compression behavior of HPC two different continuous stepwise linearly approximated degradation functions for HPC in tension and in compression are used. The experimental three-point bending tests at low-cycle using notched beams of pure HPC are performed. Load–CMOD (crack mouth opening displacement) curves are plotted using the measured experimental data and residual stiffness–CMOD curves are calculated using these experimental Load–CMOD curves. The data used for the interpolation of degradation functions are calibrated using the experimental results for three-point bending tests. For that purpose the uniaxial tension and uniaxial compression tests and three-point bending beam test for HPC are simulated numerically. The accuracy of the proposed numerical model using the presented integration algorithm is verified by comparing the degradation of stiffness in numerical and experimental results.

提出了一种弹塑性相场模型的开发，该模型能够预测高性能混凝土的非线性行为(HPC) 在低周疲劳期间。制定了遵循 Drucker-Prager 屈服准则的弹塑性损伤模型。对于 HPC 的非对称拉伸-压缩行为的建模，使用了 HPC 在拉伸和压缩中的两种不同的连续逐步线性近似退化函数。使用纯 HPC 的缺口梁在低周期进行了实验性三点弯曲试验。使用测量的实验数据绘制负载-CMOD（裂缝张口位移）曲线，并使用这些实验负载-CMOD 曲线计算残余刚度-CMOD 曲线。用于退化函数插值的数据使用三点弯曲测试的实验结果进行校准。为此，对 HPC 的单轴拉伸和单轴压缩试验以及三点弯曲梁试验进行了数值模拟。使用所提出的数值模型的准确性通过比较数值和实验结果中刚度的退化来验证积分算法。