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formula_7_3

codes.eurocode.en_1992_1_1_2004.chapter_7_serviceability_limit_state.formula_7_3

Formula 7.3 from EN 1992-1-1:2004: Chapter 7 - Serviceability limit state (SLS).

Classes:

  • Form7Dot3CoefficientKc –

    Class representing the formula 7.3 for the coefficient kc for flanges of tubular cross-sections and T-sections.

codes.eurocode.en_1992_1_1_2004.chapter_7_serviceability_limit_state.formula_7_3.Form7Dot3CoefficientKc 

Form7Dot3CoefficientKc(f_cr: KN, a_ct: MM2, f_ct_eff: MPA)

Bases: Formula

Class representing the formula 7.3 for the coefficient kc for flanges of tubular cross-sections and T-sections.

[\(kc\)] Calculates kc for flanges of tubular cross-sections and T-sections [\(-\)].

EN 1992-1-1:2004 art.7.3.2(2) - Formula (7.3)

Parameters:

  • f_cr (KN) –

    [\(F_{cr}\)] Absolute value of the tensile force within the flange immediately before cracking due to the cracking moment calculated with [\(f_{ct,eff}\)] [\(kN\)].

  • a_ct (MM2) –

    [\(A_{ct}\)] Area of the concrete within the tension zone. The tension zone is that part of the cross-section that, according to the calculation, is under tension just before the first crack occurs [\(mm^2\)].

  • f_ct_eff (MPA) –

    [\(f_{ct,eff}\)] Average value of the tensile strength of the concrete at the time when the first cracks can be expected [\(MPa\)].

Source code in blueprints/codes/eurocode/en_1992_1_1_2004/chapter_7_serviceability_limit_state/formula_7_3.py 
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def __init__(
    self,
    f_cr: KN,
    a_ct: MM2,
    f_ct_eff: MPA,
) -> None:
    r"""[$kc$] Calculates kc for flanges of tubular cross-sections and T-sections [$-$].

    EN 1992-1-1:2004 art.7.3.2(2) - Formula (7.3)

    Parameters
    ----------
    f_cr : KN
        [$F_{cr}$] Absolute value of the tensile force within the flange immediately before cracking due to the cracking moment calculated with
        [$f_{ct,eff}$] [$kN$].
    a_ct : MM2
        [$A_{ct}$] Area of the concrete within the tension zone. The tension zone is that part of the cross-section that,
        according to the calculation, is under tension just before the first crack occurs [$mm^2$].
    f_ct_eff : MPA
        [$f_{ct,eff}$] Average value of the tensile strength of the concrete at the time when the first cracks can be expected [$MPa$].
    """
    super().__init__()
    self.f_cr = f_cr
    self.a_ct = a_ct
    self.f_ct_eff = f_ct_eff

codes.eurocode.en_1992_1_1_2004.chapter_7_serviceability_limit_state.formula_7_3.Form7Dot3CoefficientKc.latex 

latex(n: int = 3) -> LatexFormula

Returns LatexFormula object for formula 7.3.

Source code in blueprints/codes/eurocode/en_1992_1_1_2004/chapter_7_serviceability_limit_state/formula_7_3.py 
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def latex(self, n: int = 3) -> LatexFormula:
    """Returns LatexFormula object for formula 7.3."""
    return LatexFormula(
        return_symbol=r"k_c",
        result=f"{self:.{n}f}",
        equation=r"\max\left(0.9 \cdot \frac{F_{cr}}{A_{ct} \cdot f_{ct,eff}}, 0.5\right)",
        numeric_equation=rf"\max\left(0.9 \cdot \frac{{{self.f_cr:.{n}f}}}{{{self.a_ct:.{n}f} \cdot {self.f_ct_eff:.{n}f}}}, 0.5\right)",
        comparison_operator_label="=",
        unit="-",
    )