Code-check of concrete block according to Russian standards

Concrete in compression

Concrete in compression under the base plate is checked according to SP 63.13330.2012, Cl. 8.1.44 – Calculation of reinforced concrete elements for local compression:

\[ N \le \psi R_{b,loc} A_{b,loc} \]

where:

• N – local compressive force from an external load
• ψ – factor equal to 0.75 in case of non-uniform distribution of the local load across the bearing surface
• R_b,loc = φ_b R_b – design compressive resistance of concrete in case of the local impact of compressive force
• \( \varphi_b = 0.8 \sqrt{\frac{A_{b,max}}{A_{b,loc}}} \) and 1.0 ≤ φ_b ≤ 2.5 – concentration factor taking into account the triaxial stress in concrete
• R_b = R_bn / γ_b – design value of concrete axial compressive resistance
• R_bn – normative axial compressive resistance of concrete
• γ_b = 1.3 – reliability factor for concrete under compression; editable in Code setup
• A_b,loc – application area of the compressive force (bearing area surface) determined by finite element method as area in contact between the base plate and concrete block
• A_b,max – maximum design area established based on the following rules:

  • gravity centres of areas A_b,loc and A_b,max coincide
  • maximum design area is geometrically similar to the application area; the slopes are 1 vertical to 2 horizontal.

Transfer of shear

The shear action at the base plate is assumed to be transferred from the column to the concrete foundation by:

1. Friction between base plate and concrete / grout
2. Shear lug
3. Anchor bolts

Anchors

The tensile forces in anchors include prying forces and are determined by finite element analysis.

Anchors are not checked in the software.