This paper presents some of the results obtained in extensive research of the Chilean in-service network of PCC paved roads, in which measurements have been conducted in 21 test sections covering various conditions of climate, pavement structure, and age. In test slabs, simultaneous measurements were made of internal temperatures and absolute vertical displacements of slabs, as well as openings of transverse joints and faultings. The results show a "permanent" upward curling of slabs in all pavements sections included in the study, as modified by daily temperature variations. The curling is demonstrated in the field by the perceptible rocking of the slabs under the early morning traffic and by the systematic transverse cracking and corner breaks of some rather new pavements with no signs of pumping. Cracking seems to start from the surface downward and from the edges inward. Detailed evaluation of the internal stresses with the superimposed nonlinear effects of environmental and wheel loads, calibrated with these results, is under way.
Abstract