Numerical Simulation Of Fiber Motion In The Process Of Steel Fiber Reinforced Self-compacting Concrete Casting

Currently,the fiber reinforced concrete members are widely used in the field of architecture because of its excellent mechanical properties.It is of great significance to study the final distribution and orientation of fibers in members,because the distribution and orientation of fibers could directly determine the mechanical properties and behaviors.For the self-compacting concrete,the casting process will directly affect the final distribution and orientation of fiber due to its characteristics of great fluidity and free-vibration.It is difficult to simulate this kind of motion effectively only with the CFX ANSYS software,let alone get enough data to compare with the experiment.A new method has been put forward to simulate the motion of steel fibers in self-compacting concrete mixe during flow by program written by MATLAB which can call the fluid calculation module as well as Lagrangian Particle Tracking function in ANSYS CFX.The ends of a fiber are represented by two particles with fixed distance(the fiber length).ANSYS CFX simulate the motion of fibers during flow while MATLAB program control each particle belongs to a fixed fiber and guarantee the length of each fiber unchanged.To verify the method’s accuracy,with a casting experiment of steel fiber reinforced concreteto be compared,a beam of 1200mm×150mm×150mm was cast through numerical simulations.The simulation method is proved to be effective and feasible through the comparison between the simulation results and the experimental results.The new method can be used to simulate the flow of self-compacting concrete with different volume fraction of rigid fibers and analysis of the movement of fibers in the whole casting process.It is of great applicability and convenient to change each casting parameters.Then taking the above beam model as the reference object,exploring the effect of casting position change on the distribution patterns of steel fiber in the beam by changing the concrete casting position from one end of the beam to the middle of the beam,and exploring the effect of casting velocity change on the distribution patterns of steel fiber in the beam by changing the concrete casting velocity from 0.25m/s to 0.65m/s.In the end,the distribution and orientation laws of the fibers change with the two casting parameters are summarized,and put forward some useful references to the practical engineering,the experiment and the following simulation analysis.