The Long-Term Pavement Performance (LTPP) SPS-1 experiment entitled "Strategic Study of Structural Factors for Flexible Pavements" was developed to determine and evaluate the factors affecting the performance of flexible pavements. The experimental design was aimed at determining the effects of following specific pavement design features: (1) base type, (2) base thickness, (3) pavement thickness, and (4) in-pavement drainage systems. The SPS-1 experimental project in Kansas, constructed in 1993, was located in the eastbound driving lane of US-54, a major rural arterial. The experiment consisted of 12 standard SPS-1 sections, 1 Kansas DOT (KDOT) control section, and 5 supplemental sections. The service life of these sections was estimated by KDOT to be from 2 to 120 years. However, because of premature distresses, some sections were rehabilitated in 1996 and 1997. This paper discusses causes of premature distresses on some sections and the performance of other sections.
Abstract