Hi All, I am modeling an RCC Column in Abaqus, I am facing following problems :-

1. Column is not showing plastic behavior between initial yield point and peak load capacity, rather it continue linear behavior upto peak load. I have used concrete damage plasticity model to define concrete. What steps could be taken to improve plastic behavior of column?

2. Different type of results obtained by applying displacement load in the form of UDL (uniformly distributed load) and by applying Displacement load in the form of point load on the top of steel plate. Why column does not give realistic results when load is applied as UDL.? what could be possible causes?

3. I have used Steel Plate on top and bottom of column and modeled it as 3d, Deformable, solid, extrusion with same properties of steel but without defining plasticity so that is does not deform. It give better results but causes the stresses focused in the top portion of column. When i define steel plate as rigid body, it disturbs the results but deformation of column shift to center of column. 

kindly reply to these queries/