Plane of strains on the composite section

Cross-section

• Concrete grade C30/37

Construction stages

Internal forces

• Internal forces received from the third-party software for each part of the section separately 

Plane of the strain at 28 days for component 1

• Tangent modulus of elasticity is used for calculation. The tangent modulus is equaled to 1.05 · $E_{cm}$.
• Internal forces are recalculated to the center of gravity of whole cross-section (with concrete slab)

Plane of the strain at 18,250 days for component 1 - prefabricated part 

• The curvature is recalculated to the center of gravity of the total cross-section (with a concrete slab). The normal force acting in the center of gravity of the lower (prefabricated) part is located eccentrically to the center of gravity of the total cross-section (with a concrete slab) and causes an additional bending moment.
• An axial strain $ε_{x1}$ at the center of gravity of the total cross-section (with concrete slab) defines the displacement of the plane of the strain calculated on the prefabricated part relative to the center of gravity of the total cross-section (with concrete slab).

Plane of the strain at 18,250 days for component 2 - composite slab

• The curvature is recalculated to the center of gravity of the total cross-section (with a concrete slab). The normal force acting in the center of gravity of the upper part (concrete slab) is located eccentrically to the center of gravity of the total cross-section (with a concrete slab) and causes an additional bending moment.
• An axial strain $ε_{x2}$ at the center of gravity of the total cross-section (with concrete slab) defines the displacement of the plane of the strain calculated on the prefabricated part relative to the center of gravity of the total cross-section (with concrete slab).

Calculated plane of strains