Thermal cyclic loads

Am trying to model the effect of thermal loading on the backfill behind  integral abutment by using Plaxis 2D. I  modelled the concrete bridge deck as Linear Plate element and provide a prescribed displacement near  the top of the abutment. The applied displacement was obtained from the coefficient of thermal expansion of the concrete, Span of the concrete deck and the change in Temperature.  

I have two questions,

  1. In this scenario, how can I take into account the creep and shrinkage deformation of the concrete bridge deck with time…?
  2. How can I simulate several numbers of cyclic loads...? i.e. Number of loading cycles near the top of bridge abutment e.g. 200
  • Dear Gabriel,

    1) You could either use the same approach as for the thermal load and translate creep and shrinkage deformation into a prescribed displacement that you apply. Alternatively you could decide to model the slab not as plate element but as volume elements and use the concrete constitutive model as this model can take into account creep and shrinkage.

    2) Again 2 options. The first one is rather obvious: just use a lot of calculation phases to increase and decrease the prescribed displacement. But easier is to define a dynamics analysis phase and prescribe the 200 cycles as time dependent prescribed displacement.

    With kind regards,

    Dennis Waterman