# Steel Beam Web Stiffener Analysis Calculator

Web Yielding, Crippling, Buckling, and Stiffener Criteria for Concentrated Load or Reaction

Per AISC 9th Edition Manual (ASD)

#### Input Data

Beam Size: | ||
---|---|---|

Select: | ||

Beam Load or End Reaction: | ||

Load or Reaction? (P/R) | ||

P or R = | kips | |

Design Parameters: | ||

Beam Yield, Fyb = | kips | |

Bearing Length, N = | in. | |

Unbraced Length, Lb = | ft. | |

Distance to P or R, x = | ft. | |

Loaded Flg. Restrained? | ||

Stiffener Thickness, ts = | kips | |

Stiffener Yield, Fys = | kips | |

Number of Stiff. Pairs = | ||

Beam Properties: | ||

d = | in. | |

tw = | in. | |

bf = | in. | |

tf = | in. | |

k = | in. |

#### Results

**TABLE J2.4**

Minimum Size of Fillet Welds

Material Thickness of Thicker Part Joined (in.) | |

Minimum Size of Fillet Weld (in.) | |

To 1/4 inclusive | 1/8 |

Over 1/4 to 1/2 | 3/16 |

Over 1/2 to 3/4 | 1/4 |

Over 3/4 | 5/16 |

For 1-pair of stiffeners, assumed effective width of beam

web to be included in composite section is as follows:

For interior load (P): 25*tw

For end load/reaction (R): 12*tw

For 2-pairs of stiffeners, assumed effective width of beam web

to be included in composite section is as follows:

For interior load (P): 25*tw+3"

For end load/reaction (R): 12*tw+3" For 3-pairs of stiffeners, assumed effective width of beam web

to be included in composite section is as follows:

For interior load (P): 25*tw+6"

For end load/reaction (R): 12*tw+6"

web to be included in composite section is as follows:

For interior load (P): 25*tw

For end load/reaction (R): 12*tw

For 2-pairs of stiffeners, assumed effective width of beam web

to be included in composite section is as follows:

For interior load (P): 25*tw+3"

For end load/reaction (R): 12*tw+3" For 3-pairs of stiffeners, assumed effective width of beam web

to be included in composite section is as follows:

For interior load (P): 25*tw+6"

For end load/reaction (R): 12*tw+6"

For 1-pair of stiffeners, assumed effective width of beam

web to be included in composite section is as follows:

For interior load (P): 25*tw

For end load/reaction (R): 12*tw

For 2-pairs of stiffeners, assumed effective width of beam

web to be included in composite section is as follows:

For interior load (P): 25*tw+3"

For end load/reaction (R): 12*tw+3"

For 3-pairs of stiffeners, assumed effective width of beam

web to be included in composite section is as follows:

For interior load (P): 25*tw+6"

For end load/reaction (R): 12*tw+6"

web to be included in composite section is as follows:

For interior load (P): 25*tw

For end load/reaction (R): 12*tw

For 2-pairs of stiffeners, assumed effective width of beam

web to be included in composite section is as follows:

For interior load (P): 25*tw+3"

For end load/reaction (R): 12*tw+3"

For 3-pairs of stiffeners, assumed effective width of beam

web to be included in composite section is as follows:

For interior load (P): 25*tw+6"

For end load/reaction (R): 12*tw+6"

**Note on Fillet Weld Size vs. Connected Material Thickness:**

The minimum connected material (base metal) thickness to

develop a given fillet weld size is

determined by equating the base metal shear strength

to the fillet weld shear strength as follows:

**t(min) = (w *(SQRT(2)/2)*0.30*70*(N))/(0.40*Fy)**

where: t(min) = minimum thickness of connected material (in.)

w = fillet weld leg size (in.)

N = 1 for weld on only one side of material thickness

N = 2 for weld on both sides of material thickness

Fy = yield strength of base metal (ksi)

E70XX weld electrode is assumed above (70 ksi yield)

**Case 1 - For fillet weld on one side of material thickness:**

t(min) = 1.031*w (for Fy = 36 ksi material)

t(min) = 0.742*w (for Fy = 50 ksi material)

**Case 2 - For fillet weld on both sides of material thickness:**

t(min) = 2.062*w (for Fy = 36 ksi material)

t(min) = 1.485*w (for Fy = 50 ksi material)

**Note on Fillet Weld Size vs. Connected Material Thickness:**

The minimum connected material (base metal) thickness to

develop a given fillet weld size is

determined by equating the base metal shear strength

to the fillet weld shear strength as follows:

**t(min) = (w *(SQRT(2)/2)*0.30*70*(N))/(0.40*Fy)**

where: t(min) = minimum thickness of connected material (in.)

w = fillet weld leg size (in.)

N = 1 for weld on only one side of material thickness

N = 2 for weld on both sides of material thickness

Fy = yield strength of base metal (ksi)

E70XX weld electrode is assumed above (70 ksi yield)

**Case 1 - For fillet weld on one side of material thickness:**

t(min) = 1.031*w (for Fy = 36 ksi material)

t(min) = 0.742*w (for Fy = 50 ksi material)

**Case 2 - For fillet weld on both sides of material thickness:**

t(min) = 2.062*w (for Fy = 36 ksi material)

t(min) = 1.485*w (for Fy = 50 ksi material)

If Rv < R, then increase beam size,

namely depth (d) and/or web thickness (tw).

namely depth (d) and/or web thickness (tw).

If Rwy < P or R, then bearing

stiffeners are required for the web.

stiffeners are required for the web.

If Rwc < P or R, then bearing

stiffeners are required for the web.

stiffeners are required for the web.

If Rwb < P or R, then bearing

stiffeners are required for the web.

stiffeners are required for the web.

If ts < ts(min), then increase

stiffener plate thickness (ts).

stiffener plate thickness (ts).

If Fa < fa, then increase

stiffener plate thickness (ts).

stiffener plate thickness (ts).

If weld size > max. weld,

then increase stiffener plate thickness (ts).

then increase stiffener plate thickness (ts).

If weld size > max. weld, then

increase stiffener plate thickness (ts).

increase stiffener plate thickness (ts).

If Rv < R, then increase beam size,

namely depth (d) and/or web thickness (tw).

namely depth (d) and/or web thickness (tw).

If Rwy < P or R, then bearing

stiffeners are required for the web.

stiffeners are required for the web.

If Rwc < P or R, then bearing

stiffeners are required for the web.

stiffeners are required for the web.

If Rwb < P or R, then bearing

stiffeners are required for the web.

stiffeners are required for the web.

If ts < ts(min), then increase

stiffener plate thickness (ts).

stiffener plate thickness (ts).

If Fa < fa, then increase

stiffener plate thickness (ts).

stiffener plate thickness (ts).

If weld size > max. weld,

then increase stiffener plate thickness (ts).

then increase stiffener plate thickness (ts).

If weld size > max. weld, then

increase stiffener plate thickness (ts).

increase stiffener plate thickness (ts).

**Disclaimer: **This calculator is not intended to be used for the design of actual structures, but only for schematic (preliminary) understanding of structural design principals. For the design of an actual structure, a competent professional should be consulted.

‘Calculations courtesy of Alex Tomanovich, PE ’