What Is the DuBoys Bedload Shear Stress Sediment Transport Calculator?
The DuBoys (1879) tractive force formula is the pioneering foundation of modern alluvial sediment mechanics.
It relates unit bedload transport rate qs to excess bed boundary shear stress: qs = χ · τ0 · (τ0 - τc), where χ is the DuBoys sediment coefficient and τc is the critical threshold shear stress.
This calculator computes boundary shear stress τ0, critical shear stress from grain size d50, transport rate in kg/(s·m), and total daily channel sediment yield in tonnes/day.
How Does the DuBoys Bedload Shear Stress Sediment Transport Calculator Work?
The calculation evaluates user-provided measurements using recognized domain equations, converts between measurement units, and adjusts for real-world efficiency factors.
DuBoys Bedload Shear Stress Sediment Transport Calculator Formula & Variables
The core mathematical equation utilized by this calculator is expressed as:
Calculates boundary bed shear stress τ0, critical shear stress τc, and applies DuBoys transport parameter χ to calculate unit rate qs and total cross-sectional transport.
How to Use the DuBoys Bedload Shear Stress Sediment Transport Calculator
- Enter your primary measurements in the input fields above.
- Select your preferred units (e.g. metric or imperial) if applicable.
- Review or adjust operational assumptions such as field efficiency.
- Click Calculate to instantly generate the full results breakdown and visual chart.
- Use the Reset button at any time to clear the form and test a new scenario.
Step-by-Step Example Calculation
Gravel-Sand Bed River Flood Channel
Input Values:
Understanding Your Result
Your calculated result represents the realistic operational capacity or baseline output under the specified conditions. Comparing theoretical and effective outputs reveals the direct impact of turns, overlap, and practical downtime.
Factors That Affect the Result
Field terrain, operator experience, equipment maintenance, overlap margin, and weather conditions can significantly influence real-world output.
When Should You Use This Calculator?
Use this calculator whenever you need quick, verified estimates for job planning, budgeting, equipment sizing, or project timelines.
Assumptions & Limitations
- Bedload transport only initiates when boundary shear stress τ0 exceeds critical shear stress τc.
- For fine sands in deep rivers, bedforms (ripples and dunes) increase form drag, requiring separation of skin friction from total bed shear.
Frequently Asked Questions
Calculation Accuracy & Reference Note
This calculator implements verified, deterministic mathematical equations based on published standards. Results should be treated as professional engineering estimates; always verify critical operations with local equipment manuals and site inspections.