Highways

Heavy use of the pavements caused by traffic, cli-mate and winter service requires a highly resistantconcrete with high flexural strength. Correspon-ding requirements on road concrete are laid downin «Additional Technical Instructions for Cons-tructing Concrete Pavements» (ZTV Beton), partlyalso requirements on some concrete basicmaterials.All materials used for construction of concretepavements have...

The new concept of the urban fabric is taking on extension and is testifying increasingly to the fact that in our cities the street is not a road. Cement concrete designs have been staying abreast of these developments and architectural concrete is just one of the significant outgrowths of these...

This paper reports on the first phase of a test programme which compares the performance of concrete ground slabs with (a) no reinforcement, (b) steel fabric reinforcement, (c) steel fibre reinforcement and (d) polypropylene fibre reinforcement. The slabs were 3.0m square, 0.15 and 0.13 m deep and subjected to a...

The hitherto used standard building method using hydraulic bound regulating and base course has been criticised for frequently faiîing. If existing concrete pavements are rehabilitated, the old road structures have to be involved into the new wearing system, so that the required bearing capacity E, ~ 50 Nz'mnr' may be...

In this paper the results of several experimental studies carried out in order to determine some properties of RCC are described. These properties are important to design and to control RCC pavements: - comparison between strain modulus of different RCC and vibrated concrete mixes whose mechanical strength were similar; proposal...

The documents for conception and design of new and reinforcement works on the French national road network were updated in 1988to take into account new pavement designs and techniques: dowelled slabs, continuously reinforced concrete, thick slabs on porous course, cement processed materials subbases. The article explains: - the development of...

The dream of concrete pavement constructors, to replace the conventional difficult-to-fix reinforce-ments, which require a considerable manual work-force, with a continuous bobbin-wound reinforce-ment, has today become a reality. The chosensolution was a weldable carbon steel, with an elas-ticlimitgreater than 700MPA, a rectangular cross-section 40 mm x 2 mm, slotted for...

Recyclingmaterials and industrial by-products are suitable for building purposes if the constructions made of them adequately withstand all loads occuring during the scheduled period of utilization and if they do not affect the environment unac-ceptably. Therefore the evaluation of recycling-and secondary materials must cover both the cons-tructional and the ecological...

In Spain the development of cement, specially for concrete pavements, has been based on making use of fly ash in cement production. Such a development was achieved after studying the characteristics of the available fly ash and the respective experiencies. The results led to a widespread use of this type...

The use of concrete setts in France has been growing for a decade, especially on urban roads. This technique, inspired by stone setts, but also by such precast concrete products as kerbs and gutters, very quickly generated needs: for design methods, for standardization of the product, for rules for use....

One concrete pavement just built was showing some located transverse cracking. In order to evaluate the cracking cause, longitudinal displacements were measured in some cracks and transverse joints. Results obtained showed that concrete cracking was reflected from cement treated base cracks, and allowed to verify that such phenomena happened in...

Maintenance problems in asphalt concrete overlays over portland cement concrete pavements may result from reflection cracking at the location of working joints and cracks in the underlying slab. Two methods of reflection crack control which have been used by many agencies in the United States within the past ten years...