#### Topic: modelling approach one-way slab

For my master thesis I am modelling a part of a continious slab system in order to specify the additional load carrying capacity by arching action.

I have several questions regarding this topic

1) First of all ragarding the modelling approach. As for one-way spanning slab a 2D moddeling approach over the height is appropiate, I wonder where the difference lies between the approach of using the material concrete and reinforcement for discrete bars and afterwards quadrilateral elements or using the 2D shell material (and discrete bars)?

2) At the beginning I am trying to model experimental tests from the literature to obtain some comparison possibilities. In some these not only the horizontal displacement was restraint but also the ends of the testing slab were fixed ends which means that the rotation was blocked. Within "define boundary conditions" there is the "rotation constraint for point/line" option, which is only applicable to 2D Shell or 1D beam elements. If I dont use the 2D shell material/element how can I block the roatation of the vertical line representing the height of my slab? Is it enough to block the hoirzontal displacement of the top and bottom ?

In addition I need to model a spring (horizontal displacement) in order to consider a neighbourfield (either point spring or line spring... depending on the results)

Are the conditions concering the same line for rotation and spring compatible?

Thank you in advance for your help!