摘要
该文将起裂断裂韧度作为裂缝扩展的判定依据,应用ANSYS软件,对全级配混凝土Ⅰ型裂缝扩展过程进行数值模拟,分别计算了混凝土楔入劈拉试件的荷载-裂缝口张开位移曲线、临界裂缝长度和双K断裂韧度,并与溪洛渡大坝的断裂试验结果进行比较,吻合良好。同时,结合试验数据,将该文计算结果与《水工混凝土断裂试验规程》规定的标准尺寸试件断裂参数计算结果进行对比。结果表明:规程规定的方法也适用于大尺寸非标准试件双K断裂参数的计算,其误差率在5%以内。此外,对于全级配混凝土,只要通过试验测得其弹性模量、抗拉强度、抗压强度和起裂荷载,即可用该文提出的方法计算混凝土的双K断裂韧度和裂缝扩展全过程。应用该方法还可以得到全级配混凝土的KR阻力曲线。
The initial fracture toughness was taken as a crack propagation criterion.The Mode Ⅰ crack propagation of fully-graded concrete was simulated by using ANSYS software.Complete P-CMOD curves,critical crack lengths and double-K fracture parameters of the wedge-splitting specimens were calculated respectively.The simulated results show a good agreement with the fracture test data of the Xiluodu dam.Meanwhile,based on the experimental data,the fracture parameters of standard specimens were calculated,using the formulae specified by the Norm for fracture test of hydraulic concrete,and compared to the simulated results.It is concluded that the method proposed by the norm can also be applied to the calculation of non-standard large-size specimens,the error rate of which is within 5%.Besides,if the elastic modulus,the uniaxial tensile strength,the uniaxial compressive strength,and the initial fracture toughness of the fully-graded concrete are measured,the double-K fracture parameters,the complete process of crack propagation and the KR crack extension resistance curves can be obtained by the proposed numerical method.
出处
《工程力学》
EI
CSCD
北大核心
2013年第4期228-234,共7页
Engineering Mechanics
基金
国家自然科学基金项目(51109026)
关键词
全级配混凝土
裂缝扩展
数值模拟
断裂参数
KR阻力曲线
fully-graded concrete
crack propagation
numerical simulation
fracture parameters
KR crack extension resistance curves
