Load types
MatrixFrame® allows calculation of 4 load types:
- Dead Loads
- Imposed Loads
- Snow Loads
- Wind Loads
Load reports
The Loads Calculation system has a possibility to create new loads reports for the new input. By default the new loads report becomes the automatically numbered LR name (LR1, LR2, LR3, ...). The created loads report may be renamed to a desired name.
Calculation input
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Index |
Description |
Calculation |
Value |
Units |
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Intended to create variables for loads calculation. Variables participating in calculations are the variables to which values may be given:
Variable functions (they are united into groups by national codes; in the result, you will see the function the values of which are formed by inputting parameters to the function):
The variables will be automatically enumerated while entering variables. |
The description of variables is formal, which means that description may be freely changed and does not affect the way of calculation |
Index variables may participate in the calculator. Types of variables:
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The index variable numerical value derived by calculation. After changing the variables, the values of new variables will automatically calculated. The values may be used in Loads definition |
Intended to show the variable dimensions. The Units are identified automatically |
Calculation of wind peak velocity pressure qp (EN 1991-1-4#4.5(4.8)) by using of mean wind velocity pressure vm²(z) (EN 1991-1-4#4.3.1(4.3)) contains probability factor cprob in the second degree as cprob².
In the standard EN 1991-1-4 the related articles for cprob wind are Art. 4.2, Note 4 & Art. 4.5:
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4.2 Basic values NOTE 4 The 10 minutes mean wind velocity having the probability p for an annual exceedence is determined by multiplying the basic wind velocity vb in 4.2 (2)P by the probability factor, cprob given by Expression (4.2). See also EN1991-1-6.
4.5 Peak velocity pressure (1) The peak velocity pressure qp(z) at height z, which includes mean and short-term velocity fluctuations, should be determined.
qp(z) = (1 + 7 · Iv(z)) · ½ · ρ · vm²(z) = ce(z) · qb (4.8) qb = ½ · ρ · vb² (4.10)
In fact, this means, that qb(50 year) = ½ · ρ · vb² (Art. 4.5), where in case ref<>50 year the vb should be multiplied with cprob according to Art. 4.2, Note 4. This means, that: qb(x year) = ½ · ρ · (vb · cprob)² = (½ · ρ · vb²) · cprob² = qb(50 year) · cprob²
With: qp(z) = ce(z) · qb qp(x year) = ce(z) · qb(x year) = ce(z) · ½ · ρ · (vb · cprob)² = ce(z) · qb(50 year) · cprob² = qp(50 year) · cprob² |