Upper Table: Table of Wind profiles
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Setting | Description |
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Wind No. |
Number of the wind profile |
Integration |
Keyword specifying the calculation method
- Fast: Approximate calculation with constant spectral density in the frequency interval
- Exact: Key for applying exact integration
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Result Type |
Type of the results of the dynamic calculation
- RMS: Standard deviation (root mean square values) from the static stressing state
- Peak: Peak values of the deviation amplitudes
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Calculation rule |
Rule for superimposing the contributions of the different modes
- ABS: Summation of absolute values of the amplitudes (full correlation)
- SRSS: Pythagorean addition (no correlation between the different modes)
- DSC: Superposition with correlation factors according to Newmark/Rosenblueth
- CQC: Complete Quadratic Combination (correlation factors according to Der Kiureghian)
- CQCX: As CQC, but additional consideration of the sign of the contribution
Note: For details on mode superposition see RM User Guide, chap. 14.3.1.
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Duration |
Duration of the event (Peak value calculation) |
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Lower Tables: Edit windows for parameters of the active wind profile
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For details on wind profile parameters see RM User Guide, chap. 14.3.1. |
Description |
Descriptive text for the wind profile |
General parameters
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Basic Parameters as shown in the upper table and described above, additionally: Setting | Description |
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Y0 |
Y coordinate of the ground surface (terrain level) in the model coordinate system |
Seed |
Initial random phase number (time history) each time history run with WINDD action will use a fix constant random seed for random phases generation
- Default=0; the default seed value will always generate a unique set of random phases at different computer clock times (this changes even in seconds).
- Positive integer=1,2,3,…; The set of random phases in this case will only change with the change in input seed else program will always generate the same set of random numbers. These random numbers can be seen in TINT output excel for nodes chosen for output.
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Frequency discretization |
- DEFAULT: Non-equidistant predefined discretization. This is a default discretization with 512 frequencies and is calibrated to give accurate results for different project results.
- >0: Equidistant frequency discretization intervals are inputted. A balance between computationally performance and accuracy can be searched.
- Table name: User defined discretization is defined in variables table. A column-A defines a frequency range and column-B defines descreitization.
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Mean velocity
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Type of the distribution over the height above ground level (Yg)
For Constant distribution:
Setting | Description |
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Windd. |
Density of the air (in t / length_unit^3) |
Cc |
Climate factor (multiplier of the specified wind velocity) |
Vc |
Wind velocity (basic design value) |
For Exponential law:
Setting | Description |
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Windd. |
Density of the air (in t / length_unit^3) |
Cc |
Climate factor (multiplier of the specified wind velocity) |
Vref |
Wind velocity (basic design value at level Yref above ground level) |
T |
Time interval for averaging (currently not used) |
Alpha |
Exponent in the case of an exponential distribution law |
Yref |
Reference height (above terrain level) for exponential distribution |
For Swedish requirements:
Setting | Description |
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Windd. |
Density of the air (in t / length_unit^3) |
Cc |
Climate factor (multiplier of the specified wind velocity) |
For logarithmic distribution and logarithmic gust:
Setting | Description |
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kt |
Surface factor |
Vb |
Base velocity |
Alpha |
Factor (for logarithmic distribution) |
fy |
Slope of the linear component of "logarithmic" distribution (in m/s per m) (for logarithmic distribution) |
Yr |
Roughness parameter of the ground surface (length value) |
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Turbulence Intensity
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Type of the distribution over the height above ground level
- Constant turbulence: Turbulence intensity is constant over the height
- Inverse prop. to velocity: Turbulence intensity is inverse proportional to the wind speed
- Swedish: Turbulence intensity in accordance with the Swedish design code
- Inverse logarithmic: Inverse logarithmic distribution of the turbulence intensity
For Constant turbulence, Inverse prop. to velocity and Inverse logarithmic:
Setting | Description |
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w-long. |
Turbulence intensity in wind direction (dimensionless) |
w-vert. |
Turbulence intensity in vertical direction (normal to the wind direction) |
w-lateral |
Turbulence intensity in horizontal lateral direction (normal to the wind direction) |
For Inverse prop. to velocity:
Setting | Description |
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Vref |
Reference wind speed (for inverse proportional distribution (w = w * Vref/v)) |
For Inverse logarithmic:
Setting | Description |
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Yr |
Roughness parameter of the ground surface (length value) |
For Sweden:
Setting | Description |
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Dir. factor |
1.0 for wind in bridge longitudinal direction, 0.58284 for across wind |
Switch for graphical presentation
Setting | Description |
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Turbulence intensity |
Presentation of the turbulence intensity in the graphics window |
Standard deviation |
Presentation of the standard deviation in the graphics window |
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Gust factor
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For factorizing the mean wind in static calculations defined with WINDG. The gust factor is defined as a function of the height above ground. Constitutive law for calculating the gust factor:
Setting | Description |
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Prop. to turb. intensity |
The gust factor GF is calculated proportional to the turbulence intensity with using the formula as specified in Eurocode EN 1991-1-4, section 4.5: GF =[1+Factor*Iv(z)] with Iv turbulence intensity in mean wind direction and z = height above ground. |
Factor |
Factor for multiplying the turbulence intensity in the formula for calculating the gust factor GF Default: 7.0 (in accordance with EN 1991-1-4) GF =[1+7*Iv(z)]
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Wind Power Spectrum
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Type of the spectrum (Please see chapter 7 in RM Analyzer user guide, wind profile, for complete description of each power spectra.)
- Constant (white noise): All frequencies have the same spectral density
- Kaimal: Distribution of the spectral density according to Kaimal
- Karman: Distribution of the spectral density according to Karman
- Sweden: Energy density spectrum according to Swedish guidelines
For constant spectral density:
Setting | Description |
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w-long. |
Wave length in in wind direction [length unit] |
w-vert. |
Wave length in vertical direction (normal to the wind direction) |
w-lateral |
Wave length in horizontal lateral direction (normal to the wind direction) |
For Kaimal and Karman Spectra:
Setting | Description |
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l-long. |
Reference wave length in in wind direction [length unit] |
l-vert. |
Reference wave length in vertical direction (normal to the wind direction) |
l-lateral |
Reference wave length in horizontal lateral direction (normal to the wind direction) |
Eps |
Exponent (only for Kaimal distribution type) |
For Swedish spectrum
Setting | Description |
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Int-length |
Integral length scale [length unit] |
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Coherence data
|
Type of the coherence behavior
- Full coherence: Maximum turbulence can occur simultaneously everywhere in space
- Exponential: Description of the behavior by a matrix of decay coefficients
- Krenk: Coherence according to Swedish design code (Sweden)
- No Coherence (only TINT): This option is used for generating non coherent wind buffeting loads only for wind buffeting in time domain for uncorrelated time series calculation.
For Exponential:
Setting | Description |
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Dir. U > Distance Long. U, V, W |
Coherence parameters are defining Krenk decay function. |
Dir. V > Distance Long. U, V, W |
Rows are defining wind fluctuation distances, where column are defining the space distance relative wind coordinate system. |
Dir. W > Distance Long. U, V, W |
For more detail follow the User Guide. |
U- is in wind direction.
V- is vertical wind direction.
W- horizontal wind direction, perpendicular to U-V plane
For Krenk:
Setting | Description |
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Dir. U > Coefficients b, c |
Coherence parameters are defining Krenk decay function. |
Dir. V > Coefficients b, c |
Rows are defining wind fluctuation distances, where column are defining the space distance relative wind coordinate system. |
Dir. W > Coefficients b, c . |
For more detail follow the User Guide. |
Int-Length |
Integral length scale used in Krenk formulation. |
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