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formula_5_40b

codes.eurocode.en_1992_1_1_2004.chapter_5_structural_analysis.formula_5_40b

Formula 5.40b from EN 1992-1-1:2004: Chapter 5 - Structural Analysis.

Classes:

codes.eurocode.en_1992_1_1_2004.chapter_5_structural_analysis.formula_5_40b.Form5Dot40bCheckLateralInstability 

Form5Dot40bCheckLateralInstability(l_0t: M, b: M, h: M)

Bases: Formula

Class representing formula 5.40b for checking lateral instability in transient situations.

Check the conditions to ignore second order effects in connection with lateral instability.

EN 1992-1-1:2004 art.5.9(3) - Formula (5.40b)

Parameters:

  • l_0t (M) –

    [\(l_{0t}\)] is the distance between torsional restraints [\(m\)].

  • b (M) –

    [\(b\)] is the width of compression flange [\(m\)].

  • h (M) –

    [\(h\)] is the total depth of beam in central part of [\(l_{0t}\)] [\(m\)].

Source code in blueprints/codes/eurocode/en_1992_1_1_2004/chapter_5_structural_analysis/formula_5_40b.py 
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def __init__(
    self,
    l_0t: M,
    b: M,
    h: M,
) -> None:
    r"""Check the conditions to ignore second order effects in connection with lateral instability.

    EN 1992-1-1:2004 art.5.9(3) - Formula (5.40b)

    Parameters
    ----------
    l_0t : M
        [$l_{0t}$] is the distance between torsional restraints [$m$].
    b : M
        [$b$] is the width of compression flange [$m$].
    h : M
        [$h$] is the total depth of beam in central part of [$l_{0t}$] [$m$].
    """
    super().__init__()
    self.l_0t = l_0t
    self.b = b
    self.h = h

codes.eurocode.en_1992_1_1_2004.chapter_5_structural_analysis.formula_5_40b.Form5Dot40bCheckLateralInstability.latex 

latex(n: int = 3) -> LatexFormula

Returns LatexFormula object for formula 5.40b.

Source code in blueprints/codes/eurocode/en_1992_1_1_2004/chapter_5_structural_analysis/formula_5_40b.py 
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def latex(self, n: int = 3) -> LatexFormula:
    """Returns LatexFormula object for formula 5.40b."""
    return LatexFormula(
        return_symbol=r"CHECK",
        result="OK" if self.__bool__() else "\\text{Not OK}",
        equation=r"\left( \frac{l_{0t}}{b} \leq \frac{70}{\left( h/b \right)^{1/3}} \text{ and } \frac{h}{b} \leq 3.5 \right)",
        numeric_equation=rf"\left( \frac{{{self.l_0t:.{n}f}}}{{{self.b:.{n}f}}} \leq \frac{{70}}{{\left("
        rf" {self.h:.{n}f}/{self.b:.{n}f} \right)^{{1/3}}}} \text{{ and }} "
        rf"\frac{{{self.h:.{n}f}}}{{{self.b:.{n}f}}} \leq 3.5 \right)",
        comparison_operator_label="\\to",
        unit="",
    )