Getting Started
Getting Started
An overview of Cimbra and how to begin optimizing precast concrete designs.
Getting Started with Cimbra
Cimbra is a structural optimization tool for precast concrete design. It finds the best designs for your chosen objective — weight, cost, or embodied carbon — all verified against ACI 318-19.
Walkthrough video
A five-minute tour of Cimbra with co-founder Sandy Curth — covering login, project setup, mold and material libraries, running an optimization, and reading the results.
How It Works
- Add mold designs and materials you typically work with to the Mold and Material Libraries
- Create a project and define your spans and loads
- Select materials from the library or enter custom properties
- Choose mold geometries to optimize against (or let the optimizer choose freely)
- Run the optimization — Cimbra finds optimal designs in seconds
- Review results with full structural verification (moment, shear, deflection, serviceability)
- Export a PDF report or CSV data
Key Concepts
Single Element vs. Project Level Optimization
- Element level: Limit optimization problem to a single element by only entering data in the first line of the Input Project Data table.
- Project level (default): Define a multi-span problem with multiple rows of the Input Project Data table with different loads per span. Optimal results are generated for each span.
Note: The more complex a problem you define, the slower the optimization, however no optimization should take longer than 2-3 minutes.
Problem Types
- Prestressed: Includes prestress strands as design variables.
- Reinforced Concrete (RC): Passive rebar only. Create and select a mold with a strand count of 0 to run an optimization without prestressing.
Mold Catalog vs. Free Optimization
- Catalog mode: Select molds from your library — the optimizer finds the best design within each mold's geometry constraints. Use this mode to evaluate the products you already cast for a project you're bidding.
- Free optimization: Molds can be defined with a broader geometric range to explore (for example, a flatbed mold with a defined width and maximum depth but no fixed number of ribs, for a multi-ribbed slab where additional forms are built on top of the bed). Use this mode to see what your existing beds can produce beyond your standard sections.