Tool Documentation - No Wall, No Worry
This tool provides preliminary sizing and spacing of soldier piles for implementation in a retaining wall. Just enter the desired concrete casing diameter, maximum wall height, considered soil type, potential pile spacing, wall length, and location of the water table. The software will also provide a visualization of the considered wall.
Updated Proposal (Also updated in the Pitch Tab, here for ease of reference)
Intended users
The intended users are structural and geotechnical engineers during bid time for proposals. Specifically, this tool will be based on WSDOT and AASHTO standards for wing walls along bridges.
Need you’re trying to provide a solution or support for
I am seeking to reduce the time spent on preliminary designs for bid proposals by creating a tool for generating the sizing of soldier piles without the need for a complete design and calculation package.
Inputs - Design Variables
- Maximum Wall Height (ft)
- Wall Length
- Concrete Casing Size
- Soil Type
- Location of Water Table
- Soldier Pile Spacing
Provided Values/Constants
- Live Load Surcharge Value
- Loading from the provided soil type
- Considered Steel Sections (7 for this case)
Underlying logic of the model you’ll implement
The model will take in the maximum height of the wall and the soil type to determine the loading on the tallest pile which is equal to the maximum height of the wall. The number of the soldier piles will first be found based on the length of the wall and soldier pile spacing, with the number rounded down and the excess evenly split as overhang on each side of the wall. The loading is based on the pressure and coefficients associated with the different soil types, which the user will be allowed to pick between. It is also influenced by the spacing between the piles due to the contribution of tributary width on the piles. The soil loading is combined with water loading, which is determined if the height of the wall extends below the water table in which the pressure from the water is multiplied by the height of the submerged component of the wall. An additional component for live load surcharge will be added, but as this number is relatively standard across soldier pile walls, it will not be an option as an input from the user. Next, the strength case will be taken and the maximum moment of the pile will be found, using a similar simplified model of a cantilever with a fixed end condition. This maximum moment will be used to determine the sizing of the pile by ensuring that capacity of the chosen section is larger than that of the demand. This will all be done for the tallest cantilever. The size of the concrete casing determines the thickness of the wall.
Timeline
Brainstorming/Idea Generation: ~1 hour, includes putting together and updating the initial proposal
Gathering of necessary inputs: ~1 hours, includes sourcing soil parameters and other relevant code applications (such as what steel sections will be offered, value of live load surcharge, etc.)
Preliminary model building: ~4 hours
Debugging and clarifying model: ~2 hours
Final submittal: ~1 hour, includes final design journal and overall documentation
Outputs
- Number of Soldier Piles
- Preliminary Soldier Pile Sizing
Updates following preliminary comments: Added in a timeline mapping out the various milestones in the project. Clarified what values are held constant versus those that are design variables and added more information about the role of the concrete casing.
Updates made during design implementation: For the spacing of the piles, it was determined that the variation between the piles could be determined, but this would likely best be done in a generative design scheme in which various optimization parameters could drive the spacing. Therefore, this value was changed into a design variable. I also removed the component about the embedment depth as this would require more complicated calculations beyond the simplifications used in this instance.
