help about secnd order effect in columns

ello all,

I am an M.S student, my subject in modelling of high strength concrete column under eecentric loading. I made a model of reinforced

 concrete column with in ANSYS by solid65 to represent concrete and link8 for steel.

My model is 200*200*4000 mm, i choose multi., conc.,and elastic linear for concrete, closing crushing for it, for steel bilinear, elastic.

Slenderness ratio (l/d)=20 Although Using large displacement analysis option, model give me very small displacement (less than

 1/10 of tested sample) and show no effect of second order, and showing no cracking in tension side (model is rigid).Model end

 boundary condition: displacement restricted in three directions at one end, and in two horizontal directions at the other end.Please, if

 anyone can help me to get appropriate displacement, strains, crack for this model.

My e-mail address:hany_well70@yahoo.com