Flexible pavements distribute the wheel load to the lower layers primarily through
- AFlexural strength of the slab.
- BGrain-to-grain contact (interlayer friction).Correct
- CTensile strength of the bitumen.
- DConcrete beam action.
Solution
Concept
Flexible Pavement Load Distribution
Formula
N/A
Step-by-step solution
1. Understand how wheel loads are transferred in flexible pavements. 2. Recall that flexible pavements transmit loads to lower layers primarily through aggregate grain-to-grain contact. 3. Select Option (b) as the correct choice.
Explanation
Flexible pavements transfer heavy traffic loads downward by passing the weight directly from one particle or aggregate grain to the next through direct contact and friction between the material layers.
Shortcut
To remember flexible pavement load distribution, use the rule "Flexible = Grain-to-Grain": - Flexible Pavement: Load transferred layer by layer via direct grain-to-grain contact (particle friction). - Rigid Pavement: Load transferred across the entire slab via beam/slab action (flexural strength).
Common mistake
A common mistake is selecting Option A or D by confusing flexible pavements with rigid pavements, which rely on slab action and flexural strength to distribute loads. Another mistake is selecting Option C under the misconception that the tensile strength of bitumen carries the load, whereas bitumen acts primarily as a binder while load distribution occurs through grain-to-grain aggregate contact.
Correct answer: B) Grain-to-grain contact (interlayer friction).