|
||
|
|
||
The calculations related to column base connections is in general given by EN 1993-1-8, Article 6.2.8.
Within SCIA Engineer the normal force resistance is calculated only in case design bending moment My,Ed is equal to zero.
The compressive normal force resistance Nj,Rd is further elaborated in EN 1993-1-8, Article 6.2.5 & 6.2.8.2. The final Nj,Rd resistance is a sum of existing T-stub resistances calculated separately avoiding an overlapping of the T-stubs.
Possible T-stub components considered in the calculation for cross-sections without haunches:
- Concrete in compression under the left column flange
- Concrete in compression under the column web
- Concrete in compression under the right column flange
Possible T-stub components considered in the calculation for cross-sections with haunches:
- Concrete in compression under the left haunch flange
- Concrete in compression under the left haunch web
- Concrete in compression under the right haunch flange
- Concrete in compression under the right haunch web
The design compression resistance of a T-stub FC,pl,Rd is given by EN 1993-1-8 Article 6.2.5 (3) as:
with:
| fjd | the design bearing strength of the joint |
| beff | the effective width of the T-stub flange min[c,(a-hc)/2]+tf+c |
| leff | the effective length of the T-stub flange min(bc,b+2*c) |
| bc | width of the base plate |
| hc | height of the column section |
| a | height of the base plate |
| b | width of the column flange |
| c | additional bearing width |
| tf | thickness of the column flange |
Based on the additional bearing width, base plate and cross-section dimensions it is determined whether "Short or Large projection" and if an "overlap" of the T-stubs has to be considered. The values of beff and leff are taken accordingly for each of the components in a similar way as indicated on the picture below:
For further info see chapter: "Equivalent T-stub in compression".
The tensile normal force resistance Nj,Rd within SCIA Engineer refers to EN 1993-1-8, Article 6.2.6.5, taking into account all bolt-rows and assuming centre of compression in the bottom flange (Tension on top). The final resistance is calculated as the minimum of the "End-plate in bending" (renamed to Base plate in bending) and "Beam web in tension" components calculated separately using both individual and group approaches: