碱骨料混凝土单轴抗压试验能量演化研究

Study on uniaxial compressive strength of alkali aggregate concrete based on FDEM method

碱骨料反应是混凝土损伤的重要原因之一。充分了解碱骨料混凝土的破坏机理及损伤描述有助于预防碱骨料混凝土建筑物可能发生的结构破坏。室内试验测量得到碱骨料混凝土各项物理指标后,根据其波速的下降幅度定义了损伤变量,并通过FDEM方法建立碱骨料混凝土单轴抗压下的破坏模型。模型可以准确地模拟碱骨料混凝土的损伤、破坏。根据数值模拟结果,碱骨料显著降低了混凝土中骨料与胶结物间界面的储能能力,这也大大降低了其整体强度。

The alkali aggregate reaction is one of the important causes of concrete damage.A good understanding of the failure mechanism and damage description of alkali aggregate concrete can help prevent possible structural failure of alkali aggregate concrete buildings.After the physical indicators of alkali aggregate concrete were obtained in indoor experiments,the damage variables were defined according to the decrease amplitude of wave velocity,and the failure model under uniaxial compression of alkali aggregate concrete was established by FDEM method.The model can accurately simulate the damage and failure of alkaline aggregate concrete.According to the numerical simulation results,the alkali aggregate significantly reduces the uniaxial compressive strength of concrete.