WinFAD is a computer program developed to assist the bridge engineer in designing or checking spread and pile concrete footings subjected to eccentrically applied axial loads that produce biaxial bending moments. Acceptable spread footing sizes and pile patterns are quickly and efficiently determined using WinFAD. After the engineer selects footing plan dimensions, WinFAD determines footing thickness and areas of reinforcing steel which satisfy design specification requirements. Individual loads are entered at the service level.
AASHTO LOAD GROUPS I THROUGH VI are included in the group combinations. Individual loads, input at the service level, are factored and combined in accordance with the AASHTO group combinations for Load Factor Design. Live loadings which produce maxima for each of the two bending moments and the axial load are further subdivided into 3 cases for Load Combination Groups, I, III, IV and VI.
SEISMIC DESIGN is in accordance with AASHTO Standard Specifications for Seismic Design of Highway Bridges or Caltrans Specifications for Group VII Loading.
ARBITRARY LOADS defined by the user are easily included in the family of loadings.
DESIGN RESULTS
WinFAD calculates the areas of reinforcing steel required based on the following criteria:
- Satisfy crack control requirements
- Moment produced by LFD or LRFD factored loads
- Moment produced by Seismic loads
- 1.20 times cracking moment
- 1.33 times area required for analysis
- 0.75 times balanced reinforcement ratio
- Maximum bar spacing of 18 inches
WinFAD checks bar spacing based on the following criteria:
- Minimum AASHTO bar spacing
- Preferred Caltrans minimum bar spacing
- Maximum bar spacing of 18 inches
- Inadequate development length
