Geometry
A cantilever is a span whose far support is free. A model needs either two vertical supports or one fixed support.
Model
Joist NDS §4.3.9 · IBC 1607.4 / ASCE 7-22 §4.4
Area loads psf × spacing = plf on the joist
Line loads crossing the joists plf along the line × spacing = lb on this joist
Concentrated loads on this joist lb
Code concentrated live load checked instead of the uniform live load, not with it
IBC Table 1607.1 / ASCE 7-22 Table 4.3-1 list the concentrated load for each occupancy, applied over a 2.5 ft square (§4.4) where it produces the greatest effect. A joist carries the share of the square it supports, P × min(1, spacing / side); dead load stays on. Placements tried: midspan and each support.
Loads
Positions are from the left end of the beam. A uniform load runs from its start to its end; give different w at each end for a taper (blank w₂ = flat). Downward positive; a moment is positive counter-clockwise. Cases are the desktop's - dead, floor live, roof live, snow, wind and seismic (normal to the member; negative for uplift) and rain - entered one tab at a time and factored by its ASCE 7-22 set below. Pattern live load is a desktop feature.
Load cases and the combination set (ASCE 7-22, as the desktop app carries them)
Beam
1 · Size
2 · Species, then 3 · Grade
Reference design values from the NDS Supplement: Table 4A dimension lumber, 4B Southern Pine (tabulated by width), 4D timbers 5x5 and larger. Section properties use the actual dressed size; the size factor CF follows the nominal size and the table. Repetitive member (NDS §4.3.9): three or more joists, rafters or studs at 24 in o.c. or less, joined by a load-distributing element. Checked in ASD, dry service, normal temperature.
Material
Size
Design
Shapes and properties from the AISC Shapes Database (W shapes to 150 plf). Fy 50 ksi is ASTM A992. Cb is taken as 1.0, which is conservative.
Material
Size
Reinforcement
Ec = 57,000√f′c (ACI 318-19 §19.2.2.1), normal-weight concrete at 150 pcf. The tension bars and the stirrups are designed for the LRFD envelope: bars to §22.2 with As,min (§9.6.1.2) in one layer at the clear spacing of §25.2.1; stirrups to §22.5 (Vc from Table 22.5.5.1, Av,min where Vu > φλ√f′cbwd per §9.6.3.1, spacing limits of Table 9.7.6.2.2), with Vu taken at d from the supports (§9.4.3.2).
Stiffness: k × Ig uses the factor you give (Table 6.6.3.1.1 lists 0.35 for beams and cracked walls, 0.70 for columns and uncracked walls; a slender wall's own k is yours to set). Ie is computed per span from the designed bars: Icr of the transformed section, Mcr = frIg/yt with fr = 7.5√f′c (§19.2.3.1), Ie by Eq. 24.2.3.5a under the service D + L moment, the positive and negative sections averaged on a continuous span (§24.2.3.7). The beam is analyzed again with those Ie until they stop changing, because cracking moves moment between spans.
Material
Size
Any member with a known E and I: glulam, LVL, aluminum, a built-up section. Analysis only; no design check runs.
Each span takes a section: pick it beside the span in Geometry. The model draws every span in its section's colour with the section's name.
Results
Joist check
Design check
Reactions
Reactions are reported per basic load case, never pre-combined — apply your own combination factors when you carry them into a column or footing.
Deflection
Limits per IBC Table 1604.3, taken on the controlling span.
Load combinations ASCE 7-22 §2.3.1 / §2.4.1
Export
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Printing this page carries the StructuralClaw watermark. The reviewer-ready calc package, with the governing code section on every value, is a desktop deliverable.