NEHRP-2020 Web Service Documentation
This software is preliminary or provisional and is subject to revision.
It is being provided to meet the need for timely best science. The
software has not received final approval by the U.S. Geological Survey
(USGS). No warranty, expressed or implied, is made by the USGS or the
U.S. Government as to the functionality of the software and related
material nor shall the fact of release constitute any such warranty. The
software is provided on the condition that neither the USGS nor the U.S.
Government shall be held liable for any damages resulting from the
authorized or unauthorized use of the software.
The documentation below is still being finalized.
Furthermore, vertical response spectra outputs have not yet been added.
Request Parameters
Required parameters
- latitude
-
Latitude of site of interest, in decimal degrees
Example:34.05 - longitude
-
Longitude of site of interest, in decimal degrees
Example:-118.25 - riskCategory
-
Risk Category, as defined in Chapter 1
Options:I, II, III, or IV - siteClass
-
Site Class, as defined in Chapter 20
Options:Default, A, B, BC, C, CD, D, DE, E - title
-
Title for this request (can be blank)
Example:Los Angeles site
Output
Web service response
- request
-
- date
-
Timestamp, in format YYYY-MM-DDThh:mm:ssZ
Example:“YYYY-MM-DDThh:mm:ssZ” - referenceDocument
-
Seismic design reference document
Example:“NEHRP-2020” - status
-
Status of response to request, either “success” or
“error”
Example:“success” - url
-
URL of request that returns this response
Example:“ … /nehrp-2020.json?latitude=34&longitude=-118&riskCategory=III&siteClass=C&title=Example” - parameters
-
- latitude
-
Latitude of site of interest, in decimal degrees
Example:34.05 - longitude
-
Longitude of site of interest, in decimal degrees
Example:-118.25 - riskCategory
-
Risk Category, as defined in Chapter 1
Options:I, II, III, or IV - siteClass
-
Site Class, as defined in Chapter 20
Options:Default, A, B, BC, C, CD, D, DE, E - title
-
Title for this request (can be blank)
Example:Los Angeles site
- response
-
- data
-
- pgam
- PGAM, the mapped Geometric-Mean Maximum Considered Earthquake (MCEG) peak ground acceleration for the user-specified Site Class, in units of g
- sms
- SMS, the MCER spectral response acceleration for short periods (of the two-period spectrum) and the user-specified Site Class
- sm1
- SM1, the MCER spectral response acceleration for 1 second (of the two-period spectrum) and the user-specified Site Class
- sds
- SDS, the design spectral response acceleration for short periods (of the two-period spectrum) and the user-specified Site Class
- sd1
- SD1, the design spectral response acceleration for 1 second (of the two-period spectrum) and the user-specified Site Class
- sdc
- Seismic design category
- ss
- SS, the MCER spectral response acceleration at 0.2 seconds for Site Class BC
- s1
- S1, the MCER spectral response acceleration at 1 second for Site Class BC
- ts
- T s = S D1 / S Ds , in Seconds
- t0
- T 0 = 0.2 * T s , in Seconds
- tl
- TL, the mapped long-period transition period, in seconds
- cv
- Cv, the vertical coefficient
- multiPeriodDesignSpectrum
-
Multi-period design response spectrum
- periods
- Array of spectral periods, in seconds
- ordinates
- Array of spectral response accelerations, in units of g
- multiPeriodMCErSpectrum
-
Multi-period design response spectrum
- periods
- Array of spectral periods, in seconds
- ordinates
- Array of spectral response accelerations, in units of g
- twoPeriodDesignSpectrum
-
Two-period design response spectrum
- periods
- Array of spectral periods, in seconds
- ordinates
- Array of spectral response accelerations, in units of g
- twoPeriodMCErSpectrum
-
Two-period Risk-targeted Maximum Considered Earthquake (MCER)
response spectrum
- periods
- Array of spectral periods, in seconds
- ordinates
- Array of spectral response accelerations, in units of g
- verticalDesignSpectrum
-
Vertical design response spectrum
- periods
- Array of spectral periods, in seconds
- ordinates
- Array of spectral response accelerations, in units of g
- verticalMCErSpectrum
-
Vertical Risk-targeted Maximum Considered Earthquake (MCER)
response spectrum
- periods
- Array of spectral periods, in seconds
- ordinates
- Array of spectral response accelerations, in units of g
- underlyingData
-
- pgauh
- Probabilistic uniform-hazard, geometric mean peak ground acceleration, in units of g
- pga84th
- Deterministic 84th-percentile, geometric mean peak ground acceleration, in units of g
- riskTargetedSpectrum
-
Probabilistic risk-targeted, maximum-direction response
spectrum (for 1%-in-50-years collapse probability)
- periods
- Array of spectral periods, in seconds
- ordinates
- Array of spectral response accelerations, in units of g
- eightyFourthSpectrum
-
Deterministic 84th-percentile, maximum-direction response
spectrum (without deterministic lower limit)
- periods
- Array of spectral periods, in seconds
- ordinates
- Array of spectral response accelerations, in units of g
- metadata
-
- modelVersion
- Version of the underlying USGS National Seismic Hazard Model
- vs30
- vs30, the average shear wave velocity used for the user-specified Site Class, in units of m/s
- scienceBaseURL
- URL of ScienceBase webpage where files of underlying gridded values are posted
- spatialInterpolationMethod
- Identifier for the interpolation method used to obtain data for location of interest from underlying gridded datasets
- maxDirFactors
-
Maximum-direction response scale factors
- periods
- Array of spectral periods, in seconds
- ordinates
- Array of scale factors
- dllSpectrum
-
Deterministic lower limit response spectrum for the
user-specified Site Class
- periods
- Array of spectral periods, in seconds
- ordinates
- Array of spectral response accelerations, in units of g
- pgadFloor
- Deterministic lower limit peak ground acceleration (PGAG) for the user-specified Site Class, in units of g
Example
Request
… /nehrp-2020.json?latitude=34&longitude=-118&riskCategory=III&siteClass=C&title=Example
Response
{
request:{
date:"2019-06-13T15:49:32.786Z",
referenceDocument:"NEHRP-2020",
status:"success",
url:"http://localhost:8000/ws/designmaps/nehrp-2020.json?latitude=34&longitude=-118&riskCategory=III&siteClass=C&title=Example",
parameters:{
latitude:34,
longitude:-118,
riskCategory:"III",
siteClass:"C",
title:"Example"
}
},
data:{
pgam:0.55,
sms:1.86,
sm1:1.07,
sds:1.24,
sd1:0.71,
sdc:"E",
ss:1.8,
s1:0.75,
ts:0.576,
t0:0.115,
tl:8,
cv:null,
multiPeriodDesignSpectrum:{
periods:[
0,
0.01,
0.02,
0.03,
0.05,
0.075,
0.1,
0.15,
0.2,
0.25,
0.3,
0.4,
0.5,
0.75,
1,
1.5,
2,
3,
4,
5,
7.5,
10
],
ordinates:[
0.58,
0.58,
0.59,
0.63,
0.77,
0.95,
1.09,
1.28,
1.37,
1.37,
1.34,
1.23,
1.12,
0.87,
0.71,
0.45,
0.32,
0.2,
0.14,
0.11,
0.068,
0.045
]
},
multiPeriodMCErSpectrum:{
periods:[
0,
0.01,
0.02,
0.03,
0.05,
0.075,
0.1,
0.15,
0.2,
0.25,
0.3,
0.4,
0.5,
0.75,
1,
1.5,
2,
3,
4,
5,
7.5,
10
],
ordinates:[
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1.31,
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0.48,
0.3,
0.21,
0.16,
0.1,
0.068
]
},
twoPeriodDesignSpectrum:{
periods:[
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0.05,
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1,
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2,
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2.1,
2.15,
2.2,
2.25,
2.3,
2.35,
2.4,
2.45,
2.5,
2.55,
2.6,
2.65,
2.7,
2.75,
2.8,
2.85,
2.9,
2.95,
3,
3.05,
3.1,
3.15,
3.2,
3.25,
3.3,
3.35,
3.4,
3.45,
3.5,
3.55,
3.6,
3.65,
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3.85,
3.9,
3.95,
4,
4.05,
4.1,
4.15,
4.2,
4.25,
4.3,
4.35,
4.4,
4.45,
4.5,
4.55,
4.6,
4.65,
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4.75,
4.8,
4.85,
4.9,
4.95,
5,
5.05,
5.1,
5.15,
5.2,
5.25,
5.3,
5.35,
5.4,
5.45,
5.5,
5.55,
5.6,
5.65,
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5.95,
6,
6.05,
6.1,
6.15,
6.2,
6.25,
6.3,
6.35,
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7.95,
8,
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8.15,
8.2,
8.25,
8.3,
8.35,
8.4,
8.45,
8.5,
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8.6,
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8.7,
8.75,
8.8,
8.85,
8.9,
8.95,
9
],
ordinates:[
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0.075,
0.074,
0.074,
0.073,
0.072,
0.071,
0.07
]
},
twoPeriodMCErSpectrum:{
periods:[
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0.025,
0.05,
0.1,
0.12,
0.15,
0.2,
0.25,
0.3,
0.35,
0.4,
0.45,
0.5,
0.55,
0.58,
0.6,
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0.75,
0.8,
0.85,
0.9,
0.95,
1,
1.05,
1.1,
1.15,
1.2,
1.25,
1.3,
1.35,
1.4,
1.45,
1.5,
1.55,
1.6,
1.65,
1.7,
1.75,
1.8,
1.85,
1.9,
1.95,
2,
2.05,
2.1,
2.15,
2.2,
2.25,
2.3,
2.35,
2.4,
2.45,
2.5,
2.55,
2.6,
2.65,
2.7,
2.75,
2.8,
2.85,
2.9,
2.95,
3,
3.05,
3.1,
3.15,
3.2,
3.25,
3.3,
3.35,
3.4,
3.45,
3.5,
3.55,
3.6,
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3.8,
3.85,
3.9,
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4,
4.05,
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4.15,
4.2,
4.25,
4.3,
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4.4,
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4.5,
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],
ordinates:[
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]
},
verticalDesignSpectrum:{
periods:[
],
ordinates:[
]
},
verticalMCErSpectrum:{
periods:[
],
ordinates:[
]
},
underlyingData:null
},
metadata:{
vs30:530,
modelVersion:"v5.0.x",
pgadFloor:0.55,
pgadPercentileFactor:1,
sadFloor:{
periods:[
0,
0.01,
0.02,
0.03,
0.05,
0.075,
0.1,
0.15,
0.2,
0.25,
0.3,
0.4,
0.5,
0.75,
1,
1.5,
2,
3,
4,
5,
7.5,
10
],
ordinates:[
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1.07,
0.86,
0.6,
0.45,
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0.24,
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0.11,
0.07
]
},
sadPercentileFactor:{
periods:[
0,
0.01,
0.02,
0.03,
0.05,
0.075,
0.1,
0.15,
0.2,
0.25,
0.3,
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],
ordinates:[
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1
]
},
maxDirectionFactor:{
periods:[
0,
0.01,
0.02,
0.03,
0.05,
0.075,
0.1,
0.15,
0.2,
0.25,
0.3,
0.4,
0.5,
0.75,
1,
1.5,
2,
3,
4,
5,
7.5,
10
],
ordinates:[
1.2,
1.2,
1.2,
1.2,
1.2,
1.2,
1.2,
1.2,
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1.213,
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1.234,
1.25,
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1.256,
1.261,
1.267,
1.272,
1.286,
1.3
]
},
spatialInterpolationMethod:"linearloglinear"
}
}
}