
 DOESTD102395
The variability associated with estimating the parameters of the statistical models shall be
accounted for (Coats and Murray, 1985 and Simiu and Scanlan, 1986).
For sites within 100 km (62 miles) of a coastline, a hurricane wind probabilistic hazard
analysis provides estimates of the probability of exceeding wind speeds at a given location and
an assessment of the uncertainty in the hazard estimates. Monte Carlo simulation techniques
or an alternative method may be used to assess the probability that specified wind speeds will
be exceeded at the site (Batts, et al., 1980). This procedure consists of the following steps:
Step 1:
Select a data set of hurricanes within 250 km (155 miles) from the site.
Step 2:
Estimate the probability distributions of the hurricane parameters (e.g.,
occurrence, central pressure, direction, landfall location, and forward speed).
Step 3:
Select a wind field model to calculate maximum wind speeds as functions of the
hurricane parameters (these should include frictional effects of land and local
site conditions).
Step 4:
Perform a Monte Carlo simulation to simulate the hurricane parameters and
determine the associated maximum wind speed at the site.
Step 5:
Assess the exceedance probabilities of wind speeds.
A preliminary hurricane wind hazard analysis may be performed to assess the magnitude of
hurricane wind speeds by using reported results of hurricane hazard analyses such as those in
Batts, et al., (1980).
A tornado hazard analysis consists of the following steps:
Step 1:
Compile, obtain, and update as necessary a data set of tornadoes for the area.
Step 2:
Develop occurrenceintensity relationship.
Step 3:
Develop areaintensity relationship.
Step 4:
Calculate probability of a point experiencing tornado intensity.
Step 5:
Calculate probability of tornado wind speeds exceeding specified values.
The tornado hazard models described in Boissonnade et. al.(2000), Coats and Murray (1985)
are acceptable for use in conducting a site tornado probabilistic hazard analysis.
A9

Privacy Statement  Press Release  Copyright Information.  Contact Us 