单轴拉伸荷载作用下轻骨料混凝土断裂行为的细观力学模拟

Micromechanical Simulation on the Fracture Behavior of Lightweight Aggregate Concrete under Uniaxial Tension

从轻骨料混凝土的细观结构出发,将轻骨料混凝土看作是由砂浆基质、轻骨料以及它们之间的界面层组成的三相复合材料.用有限元方法研究其界面层对于宏观试样断裂特征及其强度影响,并模拟了轻骨料混凝土在单轴拉伸载荷作用下的破坏形式,验证了轻骨料的力学性能对于轻骨料混凝土的断裂所起的重要作用.

The fracture process of the lightweight aggregate concrete （LWAC） subjected to a uniaxial tension is simulated by the finite element method which is based on the microstructure of the LWAC. In the simulation, the LWAC is assumed to be a three-phase composite composed of matrix （mortar）, inclusions （lightweight aggregate） and the bond layer between the mortar and the lightweight aggre- gate. The simulation results show that the bond layer has few effects on the macroscopic mechanical performance of LWAC and the mechanical properties of the aggregate are important to the fracture of the LWAC.