seismic analysis as a tool for checking the structural system

Fig.3 Structural 3D model
Fig.4 R/C shear walls
Static Loads
Basement
Dead load Self-weight of foundation slab 500 mm 12.5 kN/m 2
Self-weight of concrete wall 300mm
19.5 kN/m
Ground-floor
Dead load Self-weight of slab 200 mm 5 kN/m 2
Additional self-weight 2.5 kN/m 2
Self-weight of masonry partition walls 5.6 kN/m 2
First-floor
Dead load Self-weight of slab 200 mm 5 kN/m 2
Additional self-weight 2.5 kN/m 2
Self-weight of masonry partition walls 4.9 kN/m 2
Roof
Dead load Self-weight of slab 200 mm 5 kN/m 2
Additional self-weight of concrete cover 3.75 kN/m 2
Seismic load
The site ground acceleration is quite high reaching the value of a g =3.2ms -2 . The soil
parameters are similar to the soil class B (ENV1998). It is assumed a „Low“-ductile structure
and then the calculation of behaviour factor is taken according to (ENV 1998-1-3). Choice of
a „Low“-ductile structure is due to the fact, that the cross-sectional reinforcement does not
allow adequate rotational capacity.
q 0 =5 for R/C frame structure,
k D =0.5 - ductility class factor (DC „L“),
k R =0.8 - structural irregularity factor,
q=q 0 k D k R =2.
Because ductility class “L” was chosen, the masonry walls (thickness 400mm) are not taken
into account as structural elements. In spite of this, the masonry walls should be furnished
with a provision to protect them against falling out of the R/C frame during seismic design
situation. The inelastic (q=2) design response spectrum, shown on Fig.5, is assumed.
ANSYS konference 2008
16. ANSYS FEM Users‘ Meeting & 14. ANSYS CFD Users’ Meeting
Luhačovice 5. - 7. listopadu 2008
- 3 -