ABSTRACT
Abstract The paper presents results of an investigation on reflective cracking carried out in the Technical University o f Gdansk. Three research projects, sponsored by District Directorate of Public Roads, are presented. The first project has been carried out since autumn 1988 on an 18 km long section o f National Road No 7, which cracked transversally after cold winters of mid-eighties. Probable reasons for the cracking were investigated and repair solutions were proposed. In the second project a PCC pavement of National Route 22, which required a new overlay due to surface defects after over 40-year service was observed. Data on development of reflective cracks is given. Finally, a research, which started in 1994 on a 0.5 km long experimental section of semi-rigid pavement, is presented. Results o f investigation on load transfer across cracks in cement stabilized base layer are given and discussed. Keywords: Pavement, semi-rigid, reflective cracking, load transfer, Poland
1 Introduction Poland is a country where use of cement treated bases is frequent and has a long tradition. One of the main reasons is the lack of rock deposits in the central and northern parts o f the country. On semi-rigid pavements, reflective cracking of asphalt wearing course is normally observed, and occurs with different frequency (from few cracks per 1 km up to more than 10 per 100 m).
