Tables8 approximate analysis
Approximate inelastic moment redistribution
PDF page 356 · AISC 360-22
4 tables appear under this heading.
1. PDF page 356
| Symbol | Definition | Section |
|---|---|---|
| Ar | Area of properly developed slab reinforcement parallel to the steel beam and within the effective width of the slab, in.2 (mm2) | I3.2b |
| B | Overall width of rectangular HSS, in. (mm) | I3 |
| C | Compression force in the concrete slab, kips (N) | I3.2a |
| Cf | Compression force in concrete slab for fully composite beam; smaller of FyAs and 0.85f'Ac, kips (N) | I3.2 |
| D | Heat perimeter, in. (mm) | App. 4.2.2 |
| Fy | Reported yield stress, ksi (MPa) | App. 5.2.2 |
| Fyr | Specified minimum yield stress of the slab reinforcement, ksi (MPa) | I3.2b |
| Fys | Static yield stress, ksi (MPa) | App. 5.2.2 |
| H | Overall height of rectangular HSS, in. (mm) | I3 |
| H | Height of anchor, in. (mm) | I8.2 |
| ILB | Lower-bound moment of inertia, in.4 (mm4) | I3.2 |
| Ineg | Effective moment of inertia for negative moment, in.4 (mm4) | I3.2 |
| Ip | Moment of inertia of the steel faceplates, in.4 (mm4) | I1.6b |
| Ipos | Effective moment of inertia for positive moment, in.4 (mm4) | I3.2 |
| Is | Moment of inertia for the structural steel section, in.4 (mm4) | I3.2 |
| Itr | Moment of inertia for fully composite uncracked transformed section, in.4 (mm4) | I3.2 |
| Iw | Moment of inertia for the major principal axis, in.4 (mm4) | Table C-F10.1 |
| Iy Top | Moment of inertia of the top flange about an axis through the web, in.4 (mm4) | F1 |
| Ks | Secant stiffness, kip-in. (N-mm) | B3.4 |
| L | Unbraced member length of steel encasement, in. (mm) | I2.2a |
| Lc | Length of anchor, in. (mm) | I8.2b |
| MC | Design flexural strength at point C", determined in accordance with Section 13, kip-in. (N-mm) | I5 |
| MC | Allowable flexural strength at point C", determined in accordance with Section 13, kip-in. (N-mm) | I5 |
| MCL | Moment at the middle of the unbraced length, kip-in. (N-mm) | F1 |
| Ms | Moment at service loads, kip-in. (N-mm) | B3.4 |
| MT | Torsional moment, kip-in. (N-mm) | G3 |
| Ma1 | Sum of the moments due to the nominal lateral loads and the moments due to the nominal gravity loads on the windward side of the connection, kip-in. (N-mm) | J10.6 |
| Ma1G | Moment due to the nominal gravity loads on the windward side of the connection, kip-in. (N-mm) | J10.6 |
2. PDF page 357
| Symbol | Definition | Section |
|---|---|---|
| Ma1L | Moment due to the nominal lateral loads on the windward side of the connection, kip-in. (N-mm) | J10.6 |
| Ma2 | Difference between the moments due to the nominal lateral loads and the moments due to the nominal gravity loads on the leeward side of the connection, kip-in. (N-mm) | J10.6 |
| Ma2G | Moment due to the nominal gravity loads on the leeward side of the connection, kip-in. (N-mm) | J10.6 |
| Ma2L | Moment due to the nominal lateral loads on the leeward side of the connection, kip-in. (N-mm) | J10.6 |
| Mo | Moment at end of unbraced length that gives the largest compressive stress in the bottom flange, kip-in. (N-mm) | F1 |
| Mo | Maximum first-order moment within the member due to the transverse loading, kip-in. (N-mm) | App. 8 |
| Mu1 | Sum of the moments due to the factored lateral loads and the moments due to the factored gravity loads on the windward side of the connection, kip-in. (N-mm) | J10.6 |
| Mu1G | Moment due to the factored gravity loads on the windward side of the connection, kip-in. (N-mm) | J10.6 |
| Mu1L | Moment due to the factored lateral loads on the windward side of the connection, kip-in. (N-mm) | J10.6 |
| Mu2 | Difference between the moments due to the factored lateral loads and the moments due to the factored gravity loads on the leeward side of the connection, kip-in. (N-mm) | J10.6 |
| Mu2G | Moment due to the factored gravity loads on the leeward side of the connection, kip-in. (N-mm) | J10.6 |
| Mu2L | Moment due to the factored lateral loads on the leeward side of the connection, kip-in. (N-mm) | J10.6 |
| M1 | Moment at other end of unbraced length, kip-in. (N-mm) | F1 |
| N | Number of cycles to failure | App. 3.3 |
| PA | Design axial compressive strength at point A″ in Figure C-15.3, determined in accordance with Section I2, kips (N) | I5 |
| PA | Allowable compressive strength at point A″ in Figure C-15.3, determined in accordance with Section I2, kips (N) | I5 |
| Pc | Design axial compressive strength at point C″, kips (N) | I5 |
| Pc | Allowable axial compressive strength at point C″, kips (N) | I5 |
| Pbr | Required brace strength, kips (N) | App. 6.1 |
| Pn | Nominal axial tensile strength, kips (N) | I6.2 |
| Pr | Required external tensile force applied to the composite member, kips (N) | I6.2 |
| Py | Tensile strength of steel section, kips (N) | I3.2a |
| Pyc | Compressive strength of steel section, kips (N) | I3.2b |
| Q̅m | Mean value of the load effect Q̅ | B3.1 |
| Qy | First moment of the area of one component about the y-axis, in.³ (mm³) | E6.1 |
| R | Radius of fillet between the flange and web of channel anchor, in. (mm) | I8.2b |
| Rcap | Minimum rotation capacity | App. 1.3.1 |
3. PDF page 358
| Symbol | Definition | Section |
|---|---|---|
| Rm | Mean value of the resistance R | B3.1 |
| SB | Stefan-Boltzmann constant | App. 4.2.2 |
| Sr | Stress range | App. 3.3 |
| Ss | Section modulus for the structural steel section, referred to the tension flange, in.³ (mm³) | I3.2 |
| Str | Section modulus for the fully composite uncracked transformed section, referred to the tension flange of the steel section, in.³ (mm³) | I3.2 |
| TF | Temperature of the fire, °F (°C) | App. 4.2.2 |
| Ts | Temperature of the steel, °F (°C) | App. 4.2.2 |
| VQ | Coefficient of variation of the load effect Q | B3.1 |
| VR | Coefficient of variation of the resistance R | B3.1 |
| Vb | Component of the shear force parallel to the angle leg with width b and thickness t, kips (N) | G3 |
| V' | Required longitudinal shear force to be transferred to the steel section or longitudinal reinforcement, kips (N) | I6.2 |
| W | Weight (mass) per unit length, lb/ft (kg/m) | App. 4.2.2 |
| a | Heat transfer coefficient, Btu/(ft²-s-°F) (W/m²-°C) | App. 4.2.2 |
| a | Bracing offset measured from the shear center in x-direction, in. (mm) | E4 |
| ac | Convective heat transfer coefficient | App. 4.2.2 |
| acr | Neutral axis location for force equilibrium, slender section, in. (mm) | 13.4 |
| ap | Neutral axis location for force equilibrium, compact section, in. (mm) | 13.4 |
| ar | Radiative heat transfer coefficient | App. 4.2.2 |
| ay | Neutral axis location for force equilibrium, noncompact section, in. (mm) | 13.4 |
| b | Bracing offset measured from the shear center in y-direction, in. (mm) | E4 |
| b | Shorter overall outside width of rectangular cross section, in. (mm) | I2.2a |
| b | Effective width of concrete slab, in. (mm) | I3.2a |
| bc | Shorter inner width of rectangular cross section, in. (mm) | I2.2a |
| cs | Specific heat of the steel, Btu/lb-°F (J/kg-°C) | App. 4.2.2 |
| dm1, dm2 | Distance between flange forces in the moment connection, in. (mm) | J10.6 |
| d1 | Distance from the centroid of the compression force in the concrete slab to the top of the steel section, in. (mm) | I3.2a |
| d1 | Distance from the centroid of the longitudinal slab reinforcement to the top of the steel section, in. (mm) | I3.2b |
| d2 | Distance from the centroid of the compression force in the steel section to the top of the steel section, in. (mm) | I3.2a |
| d2 | Distance from the centroid of the tension force in the steel section to the top of the steel section, in. (mm) | I3.2b |
| d3 | Distance from the resultant steel tension force for full section tension yield to the top of the steel, in. (mm) | I3.2 |
| d3 | Distance from Py to the top of the steel section, in. (mm) | I3.2a |
| f | Critical stress when slender element is not considered, ksi (MPa) | E7.1 |
| fv | Shear stress in angle, ksi (MPa) | G3 |
| h | Longer overall outside width of rectangular cross section, in. (mm) | I2.2a |
| hc | Shorter inner width of rectangular cross section, in. (mm) | I2.2a |
4. PDF page 359
| Symbol | Definition | Section |
|---|---|---|
| k | Plate buckling coefficient characteristic of the type of plate edge-restraint | E7.1 |
| p | Hydrostatic pressure, ksi (MPa) | I2.2a |
| q″ | Net heat flux incident on the steel member, Btu/s-ft-in. (J/s-m²) | App.4.2.2 |
| st | Tie bar spacing, in.4 (mm4) | I1.6b |
| t | Thickness of wall, in. (mm) | I2.2a |
| tf | Thickness of channel anchor flange, in. (mm) | I8.2b |
| tw | Thickness of channel anchor web, in. (mm) | I8.2b |
| zo | Coordinate along the z-axis of the shear center with respect to the centroid, in. (mm) | Table C-F10.1 |
| ΩB | Safety factor for bearing on concrete | I6.3a |
| αp | Ratio of the flexural stiffness of the steel plate to the flexural stiffness of the tie bar | I1.6b |
| β | Reliability index | B3.1 |
| β | Brace stiffness, kip/in. (N/mm) | App. 6.1 |
| βact | Actual bracing stiffness provided, kip/in. (N/mm) | App. 6.1 |
| δo | Maximum deflection due to transverse loading, in. (mm) | App. 8 |
| εF | Emissivity of the fire and view coefficient | App. 4.2.2 |
| θS | Rotation at service loads, rad | B3.4 |
| v | Poisson's ratio | E7.1 |
| φB | Resistance factor for bearing on concrete | I6.3a |
| ω | Empirical adjustment factor | E4 |