Tan Yunliang, Gu Qingheng, Ning Jianguo, Liu Xuesheng, Jia Zhichuang, Huang Dongmei
State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology, Shandong University of Science and Technology, Qingdao 266590, China.
School of Mining and Safety Engineering, Shandong University of Science and Technology, Qingdao 266590, China.
Materials (Basel). 2019 Apr 22;12(8):1309. doi: 10.3390/ma12081309.
The mechanical properties of mortar materials in construction are influenced both by their own proportions and external loads. The trend of the stress-strain curve in cracks compaction stage has great influence on the relationship between the strength and deformation of cement mortar. Uniaxial compression tests of mortar specimens with different cement-sand ratios and loading rates were carried out, and the stored and dissipated energies were calculated. Results indicated that the elastic modulus and strength of mortar specimens increase with the cement-sand ratio and loading rate. The energy dissipation shows good consistency with the damage evolution. When the loading rate is less than 1.0 mm/min, most of the constitutive energy at the peak point is stored in the specimen and it increase with cement-sand ratio. A simple representation method of axial stress in cracks compaction stage was proposed and an energy-based damage constitutive model-which can describe well the whole process of cement mortar under uniaxial compression-was developed and verified.
建筑中砂浆材料的力学性能受其自身配比和外部荷载的影响。裂缝压实阶段应力 - 应变曲线的趋势对水泥砂浆强度与变形之间的关系有很大影响。对不同水泥 - 砂比和加载速率的砂浆试件进行了单轴压缩试验，并计算了储存能和耗散能。结果表明，砂浆试件的弹性模量和强度随水泥 - 砂比和加载速率的增加而增大。能量耗散与损伤演化具有良好的一致性。当加载速率小于1.0 mm/min时，峰值点处的大部分本构能储存在试件中，且随水泥 - 砂比增加。提出了一种裂缝压实阶段轴向应力的简单表示方法，并建立并验证了一个基于能量的损伤本构模型，该模型能很好地描述水泥砂浆在单轴压缩下的全过程。
