# How is seismic hazard calculated?

## How is seismic hazard calculated?

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The damage potential of an earthquake is determined by how the ground moves and how the buildings within the affected region are constructed. Expected ground motion can be calculated on the basis of probability, and the expected ground motions are referred to as seismic hazard.

## How is PGA calculated?

PGA is calculated using attenuation function that describes the correlation between the local ground movement intensity the earthquake magnitude and the distance from the earthquake’s epicentre.

**What is SS and S1 seismic values?**

Their values represent a ground acceleration at the site as a percentage of gravity. One is called the short period (0.2 sec) acceleration Ss and the other the 1-second period acceleration S1.

### What is seismic coefficient?

The Seismic Coefficients are dimensionless coefficients which represent the (maximum) earthquake acceleration as a fraction of the acceleration due to gravity. Typical values are in the range of 0.1 to 0.3. A NEGATIVE vertical seismic coefficient represents a vertical seismic force directed UPWARDS.

### What is the objective of the seismic code?

The objective of the seismic code is to avoid building collapse. With correct implementation of the seismic code the blue central circle will disappear. Seismic codes are a sub-division of the national building codes, the implementation of which can be divided into immediate-, medium- and long-term activities.

**What does it mean to have seismic hazard in Canada?**

On the maps, seismic hazard is expressed as the most powerful ground motion that is expected to occur in an area for a given probability level. Contours delineate regions likely to experience similarly strong of ground motions. A simplified seismic hazard map indicates the relative seismic hazard across Canada.

#### How is the damage potential of an earthquake calculated?

Seismic Hazard Calculations The damage potential of an earthquake is determined by how the ground moves and how the buildings within the affected region are constructed. Expected ground motion can be calculated on the basis of probability, and the expected ground motions are referred to as seismic hazard.

#### Is the National Building Code intended for new buildings?

While the National Building Code is chiefly intended for new buildings (Article 1.1.1.1 of Division A), appendix A (appendix note A-1.1.1.1) outlines the principles by which the code should also be applied to the use and modification of existing buildings.