To obtain a better understanding of ultrathin whitetopping (UTW) pavement behavior under traffic loading and environmental effects and to collect data for calibration and development of a mechanistic design procedure, a UTW test pavement was constructed, instrumented, and load tested. The UTW pavement test section is located at the Spirit of St. Louis Airport, a general aviation airport in Chesterfield, Missouri, and is designed to carry a light aircraft load of 56 kN. The results of analyses conducted on this test pavement and its performance to date are described. The UTW test section was constructed in February 1995 and consisted of six slabs with dimensions of 1.3 x 1.3 m and a design slab thickness of 89 mm. The load testing was conducted in May and September 1995. Load-induced strains, temperature distribution, and surface profiles were measured at different locations and at different times. Pavement core samples were also taken and subjected to laboratory testing. It was observed from the evaluation that (a) there was very little vertical slab movement in spite of the temperature differential in the slabs, (b) there was no apparent change in load-induced strains (stresses) with temperature changes, (c) pavement exhibited high load transfer efficiencies across contraction joints, and (d) an interface shear strength of 689 kPa was achieved by the commonly used technique for asphalt surface preparation, milling and cleaning. A recent performance review of this pavement also showed that it has performed extremely well after over 6 years in service. Of the 11,620 sq m of UTW pavements (about 72,000 UTW panels), only 18 panels have cracked.
Samenvatting