gravel equivalent associated with a stage period (t); traffic index associated with a stage load applications value, W t); and, resistance value indicative of subgrade strength.
Open image in new window (4 where: Open image in new window GE t) gravel equivalent associated with a stage period (t); TI t) traffic index associated with a stage load applications value, W t); and, R resistance value indicative of subgrade strength.
The subgrade strength as represented by the resistance value (R) is assumed to be 20.
Laboratory investigation of subgrade strength parameter as California Bearing Ratio beneficial for design of flexible pavement, Coefficient of subgrade reaction K-Value required for design of rigid pavement, raft footing and unconfined compressive strength (UCS) is useful for determination of shear strength parameter of subgrade.
The scope of this study is to increase the subgrade strength with the addition of lime to fulfill design specification, this leads to economy in the structural thicknesses of the pavement on subgrade strengths of 2%, 3% and 4% CBR values with traffic intensities of 1, 5, 10, 20 and 30 million standard axles.
Two important factors that govern pavement design are soil subgrade strength and traffic loading.
Multiple control test sections were also built to evaluate the effect that subgrade strength, base course thickness, and/or presence of the geosynthetic had on performance.
A total of three scenarios depending on different levels of traffic or laning and different categories of subgrade strength are studied in this paper.
Results obtained from validation of these developed empirical correlation proves their reliably and accuracy to perform subgrade strength evaluation for both rigid and flexible pavement.
In addition, a simple graphical method was proposed for comparing structural and environmental performance of concrete pavements with respect to BFS content, subgrade strength, different versions of the aircraft design, fuel requirements and GHG emissions for pavement construction.
It can be observed that addition of RBI Grade 81 imparting an improvement in the soil subgrade strength.
