# Joyner Boore 1981 Intensity Model

## Class Name

• RJoynerBoore1981IntensityModel

## Location in Objects Pane

• Models > Model > Hazard > Earthquake > Intensity > Joyner Boore 1981 Intensity

## Model Description

### Model Form

• This model produces the peak ground acceleration at specified locations for given magnitude and hypocentre location input, based on the Joyner and Boore (1981) attenuation relation.
• $$PGA = {10^{ - 1.02\alpha + 0.249\beta \cdot M - {{\log }_{10}}(R) + b \cdot R + 0.26\varepsilon }}$$ where $${R}$$= radius

• Yes

## Properties

### Object Name

• Name of the object in Rt
• Allowable characters are upper-case and lower-case letters, numbers, and underscore (“_”).
• The name is unique and case-sensitive.

### Display Output

• Determines whether the model is allowed to print messages to the Output Pane.

### Magnitude

• $${M}$$ = Magnitude

### Alpha

• $${\alpha}$$ = 1, typically a normal random variable with unit mean.

### Beta

• $${\beta}$$ = 1, typically a normal random variable with unit mean.

### B

• B = 1, typically a normal random variable with unit mean.

### Epsilon

• $${\varepsilon}$$ = Model error, typically a standard normal random variable

### Hypocentre Location

• Location of the hypocenter, which automatically will yield the radius $${R}$$ to the various output locations.

### Structure Location List

• List of the locations where the intensity will be computed at them (the output will give as many intensity values as the locations provided here).

## Output

• $${PGA}$$ = peak ground accelerations (as many as the locations provided in the input)
• The output is an automatically generated generic response object, which takes the object name of the model plus “Response”.