aashto pavement design software free download

Loading can be applied to mixed traffic by use of ESALs.The characterization of subgrade support may be extended to other subgrade soils by an abstract soil support scale.In order to apply the equations developed as a result of the AASHO Road Test, some basic assumptions are needed: All PCC was of the same mix design and used the same aggregate and portland cement.JPCP was 4.6 m (15 ft) and JRCP was 12.2 m (40 ft). For JPCP and JRCP, all transverse joints were the same spacing.The loads used to develop the equations were operating vehicles with identical axle loads and configurations, as opposed to mixed traffic.Therefore, environmental factors were difficult if not impossible to extrapolate out to a longer period. The equations are based on an accelerated two-year testing period rather than a longer, more typical 20+ year pavement life.The equations were developed based on the environment at the AASHO Road Test only.The equations were developed based on the specific pavement materials and roadbed soil present at the AASHO Road Test.These equations were developed for the specific conditions of the AASHO Road Test and therefore involved some significant limitations: The following subsections discuss:įrom the AASHO Road Test, equations were developed which related loss in serviceability, traffic, and pavement thickness. The rest of this section will discuss the specific assumptions, inputs and outputs associated with the 1993 AASHTO Guide flexible pavement empirical design equation. This equation is not the only empirical equation available but it does give a good sense of what an empirical equation looks like, what factors it considers and how empirical observations are incorporated into an equation. Load transfer coefficient (value depends upon the load transfer efficiency) Modulus of rupture of PCC (flexural strength) Predicted number of 80 kN (18,000 lb.) ESALsĬombined standard error of the traffic prediction and performance predictionĭifference between the initial design serviceability index, p o, and the design terminal serviceability index, p t

Aashto pavement design software free download