ABSTRACT
In this case (a shear mode deflection) it can be seen that the modal mass is half of the total mass of the building.
The foregoing has been based on simple mathematical expressions to depict the deflected form for what is essentially a cantilever. However, for the consideration of more complex mode shapes, such as second translational ones of a tall building, or modes for structures such as dams, floors and bridges, it is necessary to adopt a somewhat more rigorous approach to
Fig. 4.2 Second translational mode for a tall building.
