Quick Answer
Calculate Road Subgrade CBR–Moisture–Density Optimization Model
Calculator
Result Interpretation
Road Subgrade CBR–Moisture–Density Optimization Model Calculator computes Subgrade CBR in dimensionless using the defined engineering formula and the input values provided.
Worked Example
Verified calculation
Given:
- Maximum CBR at Optimum Conditions = 12
- Dry Density = 1820
- Optimum Moisture Content = 11.5
- Maximum Dry Density = 1820
- Moisture Content = 11.5
Expected Result:
- Subgrade CBR = 12
Engineering Interpretation:
Under the given input conditions, the calculated result is: Subgrade CBR = 12 dimensionless.
The actual numerical result is computed by the Runtime engine using the persisted tool definition. The values shown here come from automatically validated test cases.
Formula / Method
subgrade cbr = maximum cbr at optimum conditions * pow(1 - abs((moisture content - optimum moisture content) / optimum moisture content), 2) * pow(dry density / maximum dry density, 1.5)Formula family: formula_roads_subgrade_cbr_moisture_content_density_relationship_optimizer
Variables
| Symbol | Label | Role | Description |
|---|---|---|---|
| moisture_content | Moisture Content | INPUT | Moisture Content |
| dry_density | Dry Density | INPUT | Dry Density |
| moisture_opt | Optimum Moisture Content | INPUT | Optimum Moisture Content |
| dry_density_max | Maximum Dry Density | INPUT | Maximum Dry Density |
| CBR_max | Maximum CBR at Optimum Conditions | INPUT | Maximum CBR at Optimum Conditions |
| subgrade_cbr | Subgrade CBR | OUTPUT | Subgrade CBR |
Calculation Steps
- Enter the moisture content in percent.
- Enter the dry density in kg/m3.
- Enter the optimum moisture content in percent.
- Enter the maximum dry density in kg/m3.
- Enter the maximum cbr at optimum conditions in dimensionless.
- Step 1: Compute subgrade cbr.
- Read the subgrade cbr (dimensionless) from the results.
Engineering Summary
Calculate Road Subgrade CBR–Moisture–Density Optimization Model
Frequently Asked Questions
What does this calculator calculate?
The Road Subgrade CBR–Moisture–Density Optimization Model Calculator estimates Subgrade CBR based on the input parameters you provide
Why is moisture content important in this calculation?
moisture content is directly proportional to subgrade cbr. When you enter moisture content in percent, the calculator uses it in the engineering formula to compute the output
How should I interpret the result subgrade cbr?
The calculator outputs subgrade cbr in dimensionless. The result is computed directly from the input values using the defined engineering formula
What units should I use for the inputs?
Enter each value in the units shown next to the input field: Moisture Content (percent), Dry Density (kg/m3), Optimum Moisture Content (percent), Maximum Dry Density (kg/m3), Maximum CBR at Optimum Conditions (dimensionless). Make sure all inputs use the specified units for consistent results
What assumptions does this calculator use?
This calculator uses automatically validated engineering formulas. Results are approximate and should be validated against site-specific conditions, applicable codes, and professional engineering judgment
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