Liu Xingzong, Gong Bin, Fu Yufang, Jiang Guanghui, Wang Jintao
Key Laboratory of Transport Industry of Road Structure and Material, Research Institute of Highway, Ministry of Transport, Beijing 100088, China.
School of Civil Engineering, Ludong University, Yantai 264025, China.
Materials (Basel). 2024 Sep 19;17(18):4588. doi: 10.3390/ma17184588.
The water environment greatly affects the creep deformation of recycled aggregate concrete (RAC). Hence, a humidity-stress-damage coupling numerical model was used for investigating the time-dependent deformation of RAC in the water environment in this study. Firstly, uniaxial compression and water absorption tests were performed to determine the calculation parameters of the creep numerical simulation of RAC in a water environment. Experimental results indicate that the elastic modulus and compressive strength drop as the water content increases. Then, the time-dependent deformation of RAC in a water environment was studied using a numerical simulation test of compressive creep when multiple stress levels were applied, and the critical stress for accelerated creep and the long-term strength of RAC were obtained. Finally, the influence of confining pressures on the long-term deformation of RAC in a water environment was discussed. When there is no confining pressure, the long-term strength of RAC is 23.53 MPa. However, when a confining pressure of 3.921 MPa is loaded onto RAC, the long-term strength of RAC is 47.052 MPa, which increases by 100%. Increasing confining pressures has an obvious effect on ensuring the long-term stable application of RAC in a water environment. Compared with the creep test, the method adopted in this study saves time and money and provides the theoretical basis for evaluating the time-dependent deformation of RAC in a water environment.
水环境对再生骨料混凝土（RAC）的徐变变形有很大影响。因此，本研究采用湿度 - 应力 - 损伤耦合数值模型来研究水环境中RAC的时变变形。首先，进行单轴压缩和吸水试验，以确定水环境中RAC徐变数值模拟的计算参数。实验结果表明，随着含水量的增加，弹性模量和抗压强度会下降。然后，通过施加多个应力水平时的压缩徐变数值模拟试验，研究了水环境中RAC的时变变形，并得到了加速徐变的临界应力和RAC的长期强度。最后，讨论了围压对水环境中RAC长期变形的影响。当没有围压时，RAC的长期强度为23.53MPa。然而，当对RAC施加3.921MPa的围压时，RAC的长期强度为47.052MPa，增长了100%。增加围压对确保RAC在水环境中的长期稳定应用有明显效果。与徐变试验相比，本研究采用的方法节省了时间和金钱，并为评估水环境中RAC的时变变形提供了理论依据。
