Custom Steel Beam & Plate Girder calculation report

Demand and resistance are evaluated along the full member for every ULS combination.

Depth or diameter is interpolated linearly within each segment. Widths and wall / plate thicknesses remain constant inside a segment. The diagrams show the cross-section at the start, governing and end locations.

Sign convention: positive shear is upward on the left cut face; positive bending is sagging; negative deflection is downward.

Implemented routes are limited to the stated applicability. A source screen is not a substitute for an unimplemented resistance method.

• Linear elastic, small-displacement Euler–Bernoulli bending in one vertical plane; shear deformation is neglected.
• Every segment is a doubly symmetric section bent about its major axis — an equal-flange welded I-section, a rectangular hollow section, or a circular hollow section. Wall and plate thicknesses and the width are constant within a segment; the depth or diameter varies linearly.
• The compression flange is continuously or otherwise adequately restrained so lateral-torsional buckling does not govern.
• The entered design yield strength is applicable to the actual steel grade and governing plate thickness; no catalogue grade/thickness lookup is inferred. The resistance / capacity factor shown for the active design standard is applied unless a project input is deliberately changed.
• Support bearing, load introduction, patch loading, stiffeners, welds, splices and connections require separate design.
• The selected deflection ratio is a project serviceability criterion and must be agreed for the building use and finishes.

• CSB_MECH_BEAMEuler–Bernoulli beam theory and direct stiffness method
  Linear two-node bending elements with two degrees of freedom per node, consistent nodal loads, explicit support constraints and equilibrium recovery.
• CSB_DEFLECTION_PROJECTProject serviceability criterion
  Vertical deflection is checked against the project span-ratio criterion selected by the user; the limit is not presented as a universal code limit.
• CSB_EN1990_COMBINATIONSEN 1990:2002+A1:2005 · 2002+A1:2005 · eq. 6.10, 6.14b, 6.16b; Tables A1.1 and A1.2(B); Annex B
  Persistent building STR combinations using the Eurocode-recommended partial factors (${\gamma }_G=1.35$, ${\gamma }_Q=1.50$), recommended $\psi$ values for imposed-load categories A–H, and the recommended consequence factor $K_{FI}$.
• CSB_EC3_CLASSIFICATIONEN 1993-1-1 · 2005 · 5.5 and Table 5.2
  Cross-section classification in major-axis bending using $\epsilon =\sqrt{235/f_y}$: outstand flanges and internal webs of welded I-sections, internal walls of rectangular hollow sections, and the $d/t$ limit ($50/70/90{\epsilon }^2$) of circular hollow sections. Class 4 is blocked.
• CSB_EC3_BENDINGEN 1993-1-1 · 2005 · 6.1 and 6.2.5, equations (6.12)–(6.15)
  Major-axis cross-section bending resistance uses $W_{pl}$ for Class 1–2 and $W_{el}$ for Class 3, divided by ${\gamma }_{M0}$.
• CSB_EC3_SHEAREN 1993-1-1 · 2005 · 6.2.6, equations (6.17)–(6.22)
  Plastic shear resistance with the clause 6.2.6(3) shear area: $\eta h_w{t}_w$ for welded I-sections ($\eta =1.0$), $Ah/(b+h)$ for rectangular hollow sections loaded parallel to the depth, and $2A/\pi$ for circular hollow sections.
• CSB_EC3_INTERACTIONEN 1993-1-1 · 2005 · 6.2.8, equations (6.29)–(6.30)
  For Class 1–2 equal-flange I-sections with $V_{Ed}>0.5V_{pl,Rd}$, bending resistance is reduced using $\rho =(2V_{Ed}/V_{pl,Rd}-1{)}^2$.
• CSB_EC3_LTB_SCOPEEN 1993-1-1 · 2005 · 6.3.2.1(2)
  The implemented cross-section route requires sufficient restraint to the compression flange; unrestrained tapered-member LTB is not inferred.
• CSB_EC3_15_SCOPEEN 1993-1-5 · 2006 · Section 5 (applicability referenced by EN 1993-1-1 6.2.6(6))
  The release screens when shear-buckling verification is required but does not calculate EN 1993-1-5 shear-buckling resistance; such a section is outside scope.
• CSB_DEFLECTIONEN 1990:2002+A1:2005 · 2002+A1:2005 · A1.4.2 and A1.4.3
  Vertical deflection is checked against the project criterion selected by the user; the limit is not presented as a universal Eurocode limit.
• CSB_AISC_COMBINATIONSASCE 7-22 / AISC 360-22 · 2022 · ASCE 7-22 §2.3 (LRFD) / §2.4 (ASD)
  Basic gravity strength combinations 1.4D and 1.2D + 1.6L (LRFD), or D and D + L (ASD). Wind, snow and seismic actions are not modelled. Coefficients are reconstructed from established engineering references and validated against published worked examples, pending review against the official published standard.
• CSB_AISC_CLASSIFICATIONAISC 360-22 · 2022 · Chapter B, Table B4.1b
  Width-to-thickness classification (compact / non-compact / slender) for flexure: I-flange $0.38/1.0\sqrt{E/F_y}$, I-web $3.76/5.70\sqrt{E/F_y}$, HSS wall and round $D/t$ limits. Coefficients are reconstructed from established engineering references and validated against published worked examples, pending review against the official published standard.
• CSB_AISC_BENDINGAISC 360-22 · 2022 · Chapter F (F2, F3, F7, F8)
  Flexural strength: $M_n=F_y{Z}_x$ for compact sections, with flange-local-buckling interpolation for non-compact sections and the F8 round-HSS branches. Design strength ${\varphi }_b{M}_n$ (LRFD, ${\varphi }_b=0.90$) or $M_n/{\Omega }_b$ (ASD, ${\Omega }_b=1.67$). Coefficients are reconstructed from established engineering references and validated against published worked examples, pending review against the official published standard.
• CSB_AISC_SHEARAISC 360-22 · 2022 · Chapter G (G2, G4, G5)
  Shear strength $V_n=0.6F_y{A}_w{C}_{v1}$ with $C_{v1}=1.0$ for stocky webs; the web shear-buckling range is blocked rather than computed. Design strength ${\varphi }_v{V}_n$ (${\varphi }_v=0.90$) or $V_n/{\Omega }_v$ (${\Omega }_v=1.67$). Coefficients are reconstructed from established engineering references and validated against published worked examples, pending review against the official published standard.
• CSB_AISC_LTB_SCOPEAISC 360-22 · 2022 · F2.2 (assumed Lb ≤ Lp)
  Full lateral restraint is assumed so lateral-torsional buckling does not govern; unrestrained members are outside the supported scope. Coefficients are reconstructed from established engineering references and validated against published worked examples, pending review against the official published standard.
• CSB_CSA_COMBINATIONSNBCC 2020 / CSA S16-19 · 2020 / 2019 · NBCC 2020 Table 4.1.3.2
  Gravity strength combinations 1.4D and 1.25D + 1.5L. Wind, snow and seismic actions are not modelled. Coefficients are reconstructed from established engineering references and validated against published worked examples, pending review against the official published standard.
• CSB_CSA_CLASSIFICATIONCSA S16-19 · 2019 · Clause 11 / Table 2
  Class 1–4 width-to-thickness limits: I-flange $145/170/200\sqrt{F_y}$, I-web $1100/1700/1900\sqrt{F_y}$, HSS and round-HSS limits, with $F_y$ in MPa. Class 4 is blocked. Coefficients are reconstructed from established engineering references and validated against published worked examples, pending review against the official published standard.
• CSB_CSA_BENDINGCSA S16-19 · 2019 · Clause 13.5
  Factored moment resistance $M_r=\varphi Z{F}_y$ (Class 1–2) or $\varphi S{F}_y$ (Class 3), with $\varphi =0.90$. Coefficients are reconstructed from established engineering references and validated against published worked examples, pending review against the official published standard.
• CSB_CSA_SHEARCSA S16-19 · 2019 · Clause 13.4.1.1
  Factored shear resistance $V_r=\varphi A_w{F}_s$ with $F_s=0.66F_y$ for stocky webs; the shear-buckling range is blocked. $\varphi =0.90$. Coefficients are reconstructed from established engineering references and validated against published worked examples, pending review against the official published standard.
• CSB_AS_COMBINATIONSAS/NZS 1170.0:2002 · 2002 · Clause 4.2.2
  Gravity strength combinations 1.35G and 1.2G + 1.5Q. Wind, snow and earthquake actions are not modelled. Coefficients are reconstructed from established engineering references and validated against published worked examples, pending review against the official published standard.
• CSB_AS_CLASSIFICATIONAS 4100:2020 · 2020 · Clause 5.2 / Table 5.2
  Plate-element slenderness ${\lambda }_e=(b/t)\sqrt{f_y/250}$ against ${\lambda }_{ep}/{\lambda }_{ey}$ giving the section slenderness ${\lambda }_s$; slender sections are blocked. Coefficients are reconstructed from established engineering references and validated against published worked examples, pending review against the official published standard.
• CSB_AS_BENDINGAS 4100:2020 · 2020 · Clause 5.2.1–5.2.6
  Section moment capacity $M_s=f_y{Z}_e$ with $Z_e=Z_c=\min (S,1.5Z)$ for compact sections and linear interpolation to $Z$ for non-compact sections. $\varphi =0.90$. Coefficients are reconstructed from established engineering references and validated against published worked examples, pending review against the official published standard.
• CSB_AS_SHEARAS 4100:2020 · 2020 · Clause 5.11
  Shear capacity $V_v=0.6f_y{A}_w$ for stocky webs; the shear-buckling range is blocked. $\varphi =0.90$. Coefficients are reconstructed from established engineering references and validated against published worked examples, pending review against the official published standard.