Flexible pavement design – key inputs Design of flexible pavements should account for which of the following influences?

Introduction / Context:
Flexible pavements transfer wheel loads through layered granular and bituminous materials. Performance and thickness requirements depend on multiple interacting factors.

Given Data / Assumptions:

• General highway design scenario.
• Standard flexible pavement structure.

Concept / Approach:
Load magnitudes and repetitions (axle loads, traffic spectrum), environmental effects (temperature and moisture), and subgrade strength all determine layer thicknesses and material specifications.

Step-by-Step Solution:
Wheel loads set structural demand.Traffic intensity determines cumulative damage (e.g., million standard axles).Climate drives temperature-susceptibility and moisture weakening.Subgrade CBR or modulus governs foundational support.

Verification / Alternative check:
Mechanistic-empirical design methods explicitly combine these inputs to predict strains and cumulative damage.

Why Other Options Are Wrong:
Each single factor alone is incomplete; all are needed for robust design.

Common Pitfalls:
Ignoring seasonal high-water tables; underestimating traffic growth; not calibrating material properties to local climate.

Final Answer:
all the above