Study Of Numerical Simulation For Steel Fiber Reinforced Concrete On Meso-level

Steel fiber reinforced concrete (SFRC) is a kind of complex heterogeneous compositematerial. In macro-mechanical model, it is regarded as homogeneous materials to study theirproperties. Some parameters can be obtained through a series of experiments, which willguide the engineering practice. To some extent, by simplifying the material as homogeneousmaterial will be difficult to describe the damage and failure process resulted from crackformation. In this paper, SFRC is investigated to simulate its mechanical properties asheterogeneous two-phase composites made up by steel fiber reinforcement and concretematrix at the microscopic level, without considering the interface bonding performancebetween them when they were simulated.Tensile strength and compressive strength are basic mechanical features of SFRC material,which are also the foundation of researches in complicated stress state. Concrete is typicalmulti-phase composites. After adding steel fiber reinforcement, though the concrete’s strengthwon’t increase significantly, its mechanical properties can be improved. Compared with thecommon concrete material, its brittleness will reduce, and the stress-strain curve will notappear a clear decline period. Thus the typical brittle failure can be avoided. The MATLABmathematical calculation software and ABAQUS finite element analysis software are used togenerate random numbers and simulate non-linear calculation. Representative volumeelement (RVE)3D numerical modal including randomly distributed steel fiber with differentvolume fraction and embedded steel fiber in matrix as truss unit without considering theirinterface adhesion were established. Engaging homogenization method, the experiments inother documents and debugged some of the parameters to verify the feasibility and veracityof meso-numerical simulation were compared. Then by conducting parametric analysis, thecomposite material’s mechanical behavior affected by length-diameter ratio and volumecontent change of random steel fiber is also studied.Considering the calculation time and accuracy, a2D plane strain finite element modelincluding concrete matrix, steel fiber and their cohesive layer based on bonding propertiesbetween steel fiber and concrete matrix is modeled. Set appropriate parameters according tocohesive zone model in fracture mechanics. Firstly the parameters were compared with the pull out tests of single steel fiber in references to testify the correctness of the model. Thenother factors were considered that will affect the bonding properties, such as types of steelfiber, the embedded length.