In 1999 - in the province of Noord-Brabant in the Netherlands - an eighteen-year-old asphalt road with a cementstabilised fly-ash road-base, appeared to be in bad condition. Further investigation showed that the base was almost completely disintegrated, probably due to bad drainage and due to a possibly low cement content....
Overview and Comparison of the New Belgian Standard Specifications For Concrete Roads
Belgium is made up of 3 regions: the Region of Flanders, the Walloon Region and the Brussels Capital Region. Managing and maintaining the national trunk roads is a regional matter and therefore also carried out in Belgium by three different administrative authorities. Each of these administrative authorities has drawn up...
The PIARC Guideline on in Situ Recycling of Pavements with Cement
Recycling techniques to take profit of materials from existing pavements are being increasingly used, due to different technical, economical and ecological reasons. Therefore, the Technical Committee C7/8 on Pavements of PIARC (World Road Association) has prepared three guidelines dealing respectively with hot recycling in plant of bituminous mixt ures cold...
Factors Affecting the Formation of Air Voids in Road Concrete
A greatly increased air void content in the hardened concrete has been found in recent years in some contract sections of concrete pavement. Investigations were carried out at the Research Institute of the Cement Industry on road concretes in order to determine the reason for this excessively high content. The...
Influence of Moisture on the Deformation (Warping and Curling) of Concrete Road Pavements Consisting of One or Two Layers with and without Recycled Aggregate
Depending on the environmental conditions during casting and hardening, actual temperature and moisture gradients in concrete pavement induce strains. These strains lead to deflections of the slabs or, when restrained, to stresses and in some cases, mainly in combination with traffic loads, to cracks. Concrete with recycled concrete aggregate (RC-Concrete)...
High Performance Concrete Effects of Curing Conditions
The use of high performance concrete (HPC) is becoming more popular in the United States. Many State Departments of Transportation are replacing conventional concrete especially with HPC bridge decks. Despite the growing popularity of the material, little is known on the effect of the available curing methods on the mechanical...
Road Marking on Concrete Roads
On several of the concrete roads that were constructed in Sweden during the 1990s problems have been experienced in making the road marking compound adhere to the road surface. The problem would appear to be greatest during the first few years. In earlier studies, the problem was analysed by laboratory...
A Fast and Comfortable Public Transport Lane in Continously Reinforced Concrete
The Zuidtangent is a free high quality public transport lane between the city of Haarlem and Schiphol Airpoprt. The full trajectoryi s built in continouusly reinforced concrete. In this paper some design aspects are described. Also the use of concrete as a wearing course on bridges and in tunnels is...
Measuring Device For Determining Dowel Positions on Concrete Slabs
and to secure the height position of the individual slabs. They must be positioned in the middle of the slab thickness so that they do not prevent longitudinal motion of the slabs. In modern concrete pavement construction the concrete is poured over the entire cross section width using slip form...
New Tool For Design of Concrete Pavements
New structural design software is presented that deals with flexible, composite and rigid structures. The pavement design is based on a trial-and-error process involving the use of the linear elastic multilayer model for flexible and composite pavements (Burmister's theory) and the strength of materials (Pasternaks theory) for the rigid ones.
Experimental and Theoretical Investigations on Concrete Pavements Under Critical Loadings
Experimental and theoretical investigations on deformations and stresses in concrete pavements subjected to realistic weathering conditions have been carried out. On large-size concrete slabs critical hygral and thermal loadings with boundary conditions corresponding to different field situations were simulated. The results of the experiments served to calibrate and to verify...
The Importance of High Range Water-Reducers in Concrete Quality
This paper is based on a research project, which has covered the importance of high range water-reducers (HRWR) on properties and consequently on quality of concrete. More precisely deals with the influence of six HRWR of an amount of twelve which were tested. They have been prepared concrete mixes with...