School of Engineering

Department of Civil Engineering and Industrial Design

A three-storey residential (ordinary) building is shown in Figure 1, where the value next to each column indicates the corresponding lateral stiffness. The mass of each whole floor is 2000 tonnes. The building is situated in a region with a reference PGA of 25%g (TNCR = 475 years) and where seismic hazard is dominated by events with a surface wave magnitude less than Ms 5.5. The shear wave velocity of the site is estimated to be 510m/s. The sample structure is a shear-type building. Assume a damping ratio of 5% and a behaviour factor of 3.0.

Determine:

- Number and values of frequencies of vibration;

- Modes of vibration and their shape;

- Participating masses for modes of vibration.

Using the equivalent static approach and the seismic input provided above, determine:

- Seismic horizontal base shear;

- Seismic horizontal forces at each storey;

- Bending moment and shear distributions in beams and columns

- Inter-storey drifts at each storey.