Page 3 - Structural Highway Design_Neat
P. 3
3. MATERIAL CHARACTERIZATION
Surface Course D1
Base Course D2
Subbase Course D3
Roadbed Course/Subgrade Soils
This section will present the physical and engineering properties of pavement
materials. Test procedures and classification system are introduced to establish an
understanding of the composition of pavement materials.
3.1. Subgrade/Roadbed soils:
The properties of importance included:
- Soil classification
- Plasticity
- Shear strength
- Drainage
3.2. Physical Properties:
1. Initial Soil Properties
This variability will have an influence on the final thickness and even on
the pavement type selected for construction.
2. Soil Classification
The AASHTO method of soil classification is the method most
commonly accepted by engineers in the highway field.
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