What it checks
The module designs a one-way composite slab spanning between supporting beams using a 1-ft wide design strip. It evaluates the deck capacity for the construction stage and the flexural capacity for the composite stage. The deck is treated either as composite tension reinforcement with concrete fill in the ribs or as non-composite formwork only.
The design method follows the SDI Design Manual for the construction stage and ACI 318-19 for the composite stage. The sequence of checks involves computing flexural demand and capacity, applying project load combinations, and determining the governing load case. The module also accounts for temperature and shrinkage steel over the ribs.
Inputs
- Geometry - Span length and strip width (1-ft wide design strip).
- Deck Properties - Deck type and configuration (composite tension reinforcement or non-composite formwork).
- Concrete Fill - Presence and properties of concrete fill in the ribs.
- Load Combinations - Project load combinations (Option<Vec<LoadComboConfig>>); absent falls back to ASCE 7-22 §2.3.1 strength set.
- Seismic Parameters - Ev toggle (A4, owner spec 09-08); Some(SDS > 0) folds vertical seismic effect 0.2*SDS*D into seismic combinations.
- Reinforcement - Temperature and shrinkage steel over the ribs.
What it reports
- Flexural Demand - The calculated moment demand for the 1-ft wide strip.
- Flexural Capacity - The calculated moment capacity compared against the demand.
- Construction Stage Capacity - SDI deck capacity for the construction stage.
- Composite Stage Capacity - ACI 318 flexure capacity for the composite stage.
- Governing Combination - Which load combination governed the design.
- Factor Source - Where the load factors for the governing combination came from.
- Seismic Effect - The vertical seismic effect 0.2*SDS*D if the Ev toggle is active.
- SDS Value - The governing label states the SDS if the Ev toggle is active.
Code references
The engine cites the SDI Design Manual for Composite Decks (4th Ed.) and ACI 318-19 §22.2, §9.6.1.2, and §19.2.2.1. When project load combinations are absent, the module falls back to the ASCE 7-22 §2.3.1 strength set.
Limits
The module assumes a 1-ft wide design strip for a one-way composite slab. It does not handle two-way slabs or slabs not spanning between supporting beams. The Ev toggle is optional; if None, the vertical seismic effect is off. The module does not calculate deflections or crack widths. Results are engineering aids; the engineer of record is responsible for the design.