Highways

This paper assesses the condition of a concrete motorway pavement in the Paris region to be widened from three to four lanes from the outside. The sigilificant drainage requirements of the existing pavement led to the provision of a new porous pavement. The design criteria applied for the typical crosssection...

Traffic areas are being executed to an increasing degree with roller compacted concrete. This concerns a concrete which is transported with earth-moving equipment, installed and compacted. To gather experience on concrete technology, test fields were laid. Furthermore, within the framework of a quality assurance program, comprehensive tests were performed on...

Within the PIARC Concrete Roads Technical Committee,ninecountrieshaveworkedout a common platform of recommendations for improving the longterm performance of concrete pavements by implementing appropriate design provisions, draining of interface infiltration water, use of low-erodability subbase materials, optimized drainage,and surface waterproofing. Some countries hadalready applied all or part of these design provi-sions...

Cementgrouted macadam (CM) is a 150-200 mm thick baselayer of macadam, 32-65 mm, which is stabilized to full homogeneity with a cement-slurry composed by cement, sand, flyash, air-entrainer, a superplasticizer and water. The cement-slurry is spread out by a especially equipped caterpillar-tracked asphalt-paver.

R.oadpaint containing a dissolving agent and hot applied ther-noplastic marking materials are most commonly used for roadnarking in the Netherlands. The only marking materials al-lowed on Dutch motorways are those that have proven theirsuitability in laboratory research and experimental sections on:he road. During a period of 25 years no concrete...

A stretch of the slip-road between the Al and A2 (Fiano tomano-S. Casareo) has been made of PCP (polyfunctional .omposite pavement). The system is "composite" owing to the rresence of several layers: mix cemented to cement binder, :ontinuous reinforcement concrete slab and bituminous layer; 'polyfunctional" owing to the diverse functions...

To determine the concrete strength in road surface the authors have applied an ultrasonic method. In this method ultrasonic transducers are imposed to the upper surface of the pavement slab. The distance between the transducers is constant. Next propagation time of longitudinal ultrasonic wave is measured. The time of propagation...

The method used to conduct pull-out tests on tie bars cast into the edge of an existing concrete pavement is described. The test results are used in conjunction with a simple statical procedure to design an economical system for stitching sections of longitudinal weakened plane joints in a plain jointed...

The criteria are presented for the choice of the proper instruments to detect strains/ stresses and temperatures on a stretch of composite concrete motorway paving. The following are described: project, implementation and assembly of the entire acquisition system broken down in two parts. The first is designed for controlling low...

First applications of roller compacted concrete (RCC) pavements on main highways took place in Spain in 1984. Since this year, RCC pavements have been employed in a large variety of works, their total surface exceeding 1.600.000 m2 by the end of 1989. Up to now, their behaviour has been very...

Under adversè conditions, the restraint stresses of young concrete pavements can cause the forma-tion of random cracks. In order to determine theparameters which influence the formation of thesestresses a full-scale experiment including sixdifferent test sections was performed. The experi-ment showsthe greatinfluenceof climaticconditionsin the days after placing the concrete. The analy-sis...

Until a few years ago, interest in the incorporation of fly ash into lean concrete was rather limited. A study conducted in the laboratory has demonstrated some of the advantages of the technique and shown that the optimum dosage is of the order of5 %. In Belgium, mixtures of this...