New laboratory and field investigations showed that it is possible to achieve durable concrete by using recycled aggregate above 4 mm from old pavements with cracks but no frost- or concrete structure deterioration. The concrete compressive and tensile strengths were slightly higher and the cracking sensitivity was slightly lower for...
High-Quality Concrete with Recycled Aggregates
Recycling Concrete Pavements in Motorway Construction
Concrete, which has withstood all the loads on heavily used roads for many decades, can be used again as a concrete aggegrate in road pavement construction after undergoing appropriate treatment. The example of four pavement batches prepared by 2 different companies in 1992 and 1993 on the A27 motorway m...
Reducing Traffic Noise on Cement Concrete Pavements
This paper concerns a joint research programme being undertaken by the Roads and Traffic Authority of New South Wales (Australia) and the Cement and Concrete Association of Australia. The objective of the research is to develop quieter concrete road surfaces, whilst maintaining acceptable skid resistance, by modifying the surface texture...
Concrete Recycling in Belgian Road Construction – Applications in Cement Bound Road Bases and Surfacings
For some years now the interest for the environment together with economic reasons, improvements of crushing plants and the definition of acceptance criteria have led in Belgium to an increased use of crushed concrete aggregate and sand in cement bound bases. Recent official circulars and tender specifications allow for the...
Noice Reducing Exposed Aggregate Surfaces – Experience and Recommendations
In 1990 a technique for building pavements with a noice reducing concrete surface was developed in Austria. The top layer contains aggretate with 8 mm maximum size. The surface is sprayed with a retarder and brushed the next day to expose the aggregate. This technique has been used on 120...
New from Old – Recycling Concrete Pavements
About 50% (150 km) nf the ennerete pavement on the motorway Al Vienna-Salzburg are older than 30 years and need reconstruction: The recycling method developed in 1 989/90 is based on the principle of making new from old. The old concrete pavement is used as a quarry and provides the...
Noise Reducing Concrete Block Pavements
In recent years several investigations were carried out in Germany aimed at reducing the tyre-road noise on concrete block pavements. The results show that these pavements can be constructed with a surface producing the same low traffic noise level as the reference asphalt road surface. In the paper, conclusions are...
Recycling of Concrete for the Reconstruction of the Concrete Pavement of the Motorway Vienna – Salzburg
From 1991 to 1993 60 km of carriageway were reconstructed on the motorway Salzburg-Vienna, re-using the old concrete pavement 100% on the work-site. The fine material (0/4) that resulted when crushing the old pavement was added to the old granular subbase which without would have been too coarse-grained to be...
Skid Resistance of Exposed Aggrcgate Concrete
From 1990 to 1992 exposed aggregate concrete was used for the construction of 14 sections of Austrian motorways. This technology offers a noise reduction and a higher level of skid resistance. In order to evaluate the skid resistance of these surfaces in comparison to others, measurements were carried out in...
Roadway Pavements of Recycled Concrete
In Switzerland deposits of gravel are growing scarce. For this and ecological reasons an effort is being made to recycle material, i.e. material produced by roadway demolition -instead of being dumpedshould be re-used in a way to achieve the highest possible quality. This means orderly reconstruction and separation of the...
Surface Characteristics and Driving Comfort on two Swedish Concrete Roads
In Sweden there is an increased interest in the performance based specifications of concrete roads, such as wearing resistance, friction and noice. Recently two concrete roads have been constructed with the special intention to improve the surface characteristics. Both roads were constructed with concrete that is resistant to wear and...
Reconstruction of a Section of the A9 Motorway Using Recycled Aggregate Concrete
In Germany the use of concrete with aggregates obtained from crushed concrete (RC aggregate) has been quite limited in comparison to other countries such as the USA and Austria. This situation is caused mainly by the lack of appropriate regulations for this kind of application. For this reason, the award...