| Title |
Validation Study of Floor Diaphragm Assumptions in L-Shaped Tall Buildings |
| DOI |
https://doi.org/10.5659/JAIK.2024.40.6.209 |
| Keywords |
floor diaphragm; torsional displacement; in-plane displacement; L-shape floor plan |
| Abstract |
This study evaluated the validity of assuming floor diaphragms in tall buildings with L-shaped plans. Although conventional structural design
typically assumes floor diaphragms, these buildings may not behave as expected. To investigate this, a simplified structural model with
meshed slab plate elements was used to compare results with and without the diaphragm assumption. The comparison included in-plane
displacement (DX, DY, RZ), in-plane stress of the roof slab, and shear force on the exterior wall at the first floor. The main parameter in
this study was the slab ratio connecting two perpendicular sub-units. Load combinations of lateral forces from two perpendicular sub-units can
be categorized into two types: torsional displacement caused by same-direction lateral forces and stress concentration on the slab caused by
opposite-direction lateral forces. The differences between models with and without diaphragms were significant when applying the load
combination that causes stress concentration on the connection slab. As the connecting slab ratio decreased, stress concentration on the slab
increased, but displacement at the outermost corner did not directly increase due to variations in torsion depending on the plan shape.
However, differences in displacement between the models with and without diaphragms continued to grow. Therefore, it is not recommended
to apply the floor diaphragm assumption when the connecting slab ratio is less than 50%. |