一种高韧性水泥基复合材料单轴抗压应力-应变本构模型

A Uniaxial Compressive Stress⁃strain Constitutive Model for Ultra⁃high Toughness Cement⁃based Composites

为研究纤维材料对高韧性水泥基复合材料抗压性能及应力-应变本构关系的影响,设计制作四组标准立方体试件,并对其进行抗压试验,观察试件受力的全过程和破坏形态。结果表明,高韧性水泥基复合材料抗压性能较普通混凝土均有一定程度的下降;在受压过程中,高韧性水泥基复合材料剥落量较少,破坏后仍能保持一个整体;钢纤维高韧性水泥基复合材料试件抗压强度较高。用已有本构模型对系数进行修正,提出高韧性水泥基复合材料应力-应变曲线修正模型,修正模型计算结果与试验结果吻合良好,能够较好预测高韧性水泥基复合材料抗压趋势。

In order to analyze the influences of fiber materials on the compressive performance and stressstrain constitutive relations of high toughness cementitious composite,four sets of standard cube specimens were designed and made,and the compression tests were carried out.The whole process of loading and failure pattern of the specimen were observed.The results showed that the compressive performance of high toughness cementitious composites were lower to a certain extent than those of ordinary concrete.During the compression process,the high toughness cementbased composite material has less spalling and can still maintain a whole after failure.The specimens of steel fiber high toughness cementitious composite had higher compressive strength.By referring to the existing constitutive model,the coefficients were modified,and the calculated results of the modified stressstrain curve model for high toughness cementbased composites were compared with the experimental results.It can be used to predict the compressive strength of high toughness cementbased composites.