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  • Current: Riprap and Scour Calculator
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Riprap and Scour Calculator

HEC added the Riprap and Scour calculator to HEC-RAS version 6.1.  This tool computes riprap size and gradation and the potential toe scour that the design must account for.  An introductory video and the files used in that video are included below.

Introduction and Conceptual Approach
Riprap Calculator: Sizing Rock Gradation
Step 1: Calculate Hydraulics and Select Profile
Step 2: Identify Design and Upstream Reference XSs
Step 3a: Define Manual Input Variables
Step 3b: Select Riprap Coefficient Parameters
Step 4: Compute the d30 of the Stable Rock Size
Step 5: Select Gradation to Compute Thickness
Rock Size and Weight Specifications
Limitation: Why Doesn’t the Riprap and Scour Calculator use 2D Results?
Maricopa Method
Scour Calculator: Computing Launchable Volume
Step 1: Compute Hydraulics
Step 2: Identify Design and Reference Cross Sections
Step 3: Define Manual Input Variables
Step 4: Select the Appropriate Equations
Step 5: Compute Ensemble Scour Results
Step 6: Visualizing Scour Results
Step 7: Select a Reasonable Scour Depth Based on Calculations, Regional Geology, and Engineering Judgement
Ongoing Work and Wish List
Acknowledgement
Scour References
Appendix A: Example Calculations
Riprap Examples
Scour Examples

RiprapExample.zip


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