Discrete and smeared approach

I am structural engineering student , working on discrete and smeared model of 1/4 th scale bridge girder using ANSYS software and facing some problems.

Some problems regarding discrete approach are:

 

1. can I use beam188 instead of link180 for modeling reinforcing steel???

2. what should I use value of shear transfer coefficient for open and closed crack ?? what is criteria for using these coefficient??

3. How can I apply load in multi-steps (load step1 ,load step2 ,load step3. etc) ???

4. How can I set convergence criteria??? ( 0.5% force and 5% displacement) which convergence norm should be used and  what value of MINREF (minimum reference value) be used for force and displacement???

Problems regarding smeared approach:

1. I have first created all required nodes. Solid65 is taken as element. Four set of real constant of solid65 are made, first one with material1 and all other parameter zero, second set with Volumetric ratio(VR) for main bar and other two set for skin +hanger and shear stirrups . An element of solid65 is created by selected 8 nodes with first set of real constant.By coping this element ,all other elements are generated. By going to modeling -create-modify-element attributes, required element attributes are changed. By this , smeared reinforcement is provided in desired location. Is this approach correct?????????

1. what should I use value of shear transfer coefficient for open and closed crack ??

2. In smeared approach , should I consider only main reinforcement or all reinforcement???