Clicking a load combination in the Project Tree Handler brings up the Material settings tab for that load combination. This tab consists of two or three headers. Concrete (MPa) comprises strength-related settings, Topping is optional and covers topping data, while General covers everything else.

PRE conc 001.png

The General header covers various conditions that affect the calculation. Exposure class and Life class may be defined and affect code checks where relevant. There are options for Quality control and reduced deviation and Reduced or measured geometrical data, which together with the option Low strength variation option changes partial factors for materials according to EN 1992-1-1 Annex A A2.1 and A2.2.

The "Link general data between load combinations" options allows for having these general settings be the same for all load combinations for the current element (default) or individually set per load combinations to simulate different environmental considerations in the element life cycle. Values dependent on these general values (such as cover values) are calculated from the worst case among the load combinations.

92848_-_denmark_flag.png Danish Annex

The General header holds two additional settings regarding partial coefficients for concrete. The first setting governs whether the element is prefabricated or not (in-situ), EN1992-1-1 Table 2.1a NA [1]. The other indicates the inspection level (Tightened, Normal, or Relaxed), EN1992-1-1 Table 2.1c (γ3).


The Strength class dropdown has an additional menu, accessed by pressing the [...] button. This opens a menu with options for viewing the design values for the currently selected material or entering a user-defined material.

PRE conc 002.png

Clicking the database... button gives us the list of possible materials.

PRE conc 003.png

By clicking the Create new... button, we are able to define our own material characteristics in the database. 

The definition of density is [kN/m3] instead of [kg/m3] and is given as the plain density i.e. in dry state and without reinforcement. Adjustments due to casting state and/or reinforcement are taken care of automatically in the program in accordance with EN 1991 annex A

  • Plain concrete has a base value of 24 kN/m3
  • If the element has reinforcement 1 kN/m3 is added to the base value
  • If the concrete is wet 1 kN/m3 is added to the base value

I.e. Wet concrete with reinforcement has a density of 24 kN/m3 + 1 kN/m3 + 1 kN/m3 = 26 kN/m3

If the Low strength variation option is selected together with one or both of the two other options described above, the partial factor for concrete will change according to EN 1992-1-1 Annex A A2.1 and A2.2.

For topping, the options are none, wet and cast. "None" represent a point in time before casting has commenced; at the point of this load combination, the topping has not yet been applied. Selecting "wet" for a load combination means that this is the point where the topping is applied (and thus, still wet). At that point, the topping provides no structural strength, while it still applies load. On selecting "wet" for a given load combination, program will automatically set the following load combinations as being "cast", denoting a dry, solidified topping.

Copyright 2020 StruSoft AB
PRE-Stress Documentation