双K断裂模型粘聚韧度K_(Ic)~c实用插值计算方法

为了配合<水工混凝土断裂试验规程>在工程界的推广使用,提出了双K断裂模型中在临界状态时分布在虚拟裂缝上的粘聚力σ(x)产生的粘聚韧度K_(Ic)~c的二元拉格朗日插值计算方法,进而由准脆性材料韧度三参数定律计算了混凝土起裂韧度K_K~(ini).与粘聚韧度K_(Ic)~c积分计算和简化计算方法的比较,表明此插值计算方法具有很高的精度,计算过程简化,使用计算器即可实现,便于工程人员实际使用.

A practical interpolation method for determining cohesion toughness K_(Ic)~c of double-K fracture model

To extend the application of concrete fracture test norm in engineering,a bivariate Lagrangian interpolation function method for determining double-K fracture model cohesion toughness K_(Ic)~c,of which caused by the cohesive force σ(x)along the fictitious crack zone in the critical state,is proposed.Then the initiation toughness K_K~(ini) can be easily evaluated using the three-parameter law of toughness in quasibrittle materials.Compared with the values of cohesion toughness K_(Ic)~c calculated by the numerical integration,this interpolation method is of high accuracy.Further,the calculation of K_(Ic)~c is simplified much more,all calculations can be performed with a pocket calculator and it is very convenient for practical engineers.