Bimaterial cross section:
For determination of the neutral axis position of the composite bimaterial cross section (NA_{C}) following general equation is used:
where:
 E_{B} and E_{T} is representing elasticity modulus of the bottom and top layer of the composite cross section;
 A_{B} and A_{T} is representing area of the bottom and top layer of the composite cross section;
 Z_{B} and Z_{T} is representing distances from the neutral axis of the composite cross section to the centroid of the bottom and top layer in particular.
The reduced area A_{C} of the composite bimaterial cross section is calculated using following formula:
The reduction of the second moment of inertia I_{C} of the composite cross section is performed as following:
The material properties of the composite bimaterial cross section are reduced as following:





Reduction of the composite cross section area and the second moment of area is done relative to the bottom layer of the composite cross section
The elasticity modulus of the reduced composite bimaterial cross section is taken from the bottom part of the composite cross section
Second moment of area for the top and bottom layer of the composite cross section is calculated by referencing to the neutral axis of the composite cross section geometry, without taking in to account its bimaterial nature
Using the standard composite prefabricated cross section, the bottom part of the cross section is prefabricated, where the top part of the cross section has meaning of the finishing/cover: