碾压混凝土直剪试件细观结构的数值模拟

Numerical Simulation of Shear Test of Specimen Roller Compacted Concrete on Meso-Level

从细观层次上将碾压混凝土试件当作是由硬化水泥粉煤灰砂浆、粗骨料、二者间的粘结带以及水泥砂浆中间层面组成的非均质复合材料,由随机骨料模型模拟碾压混凝土的细观结构,用非线性有限元法模拟试件在直剪作用下的细观损伤断裂,从而求得其宏观抗剪断强度.计算结果与《混凝土重力坝设计规范》所提供的参考值较为吻合,据此还进行了试件破坏机理分析.应用此种计算方法,可节省直剪试验工作量,并可进行直剪试件的尺寸效应分析,有广阔的应用前景.

The RCC is taken as two-phase composites consisting of mortar smut matrix, aggregate and bond between matrix and aggregate on meso-level. This random aggregate model is used to simulate the structure of RCC. The propagation processes of cracks and the mechanical properties of RCC in shear test are simulated u-sing finite element method. The simulation results agree with the Design Specification and test results. This numerical method is a new conception for investigating fracture mechanism and mechanical properties of RCC.