The paper contains investigations of concrete debris generated during the compression testing of drilled cores and during hydrodemolition, l3ased on sieve analyses, average diameters of the debris samples are estimated. It is found that a fairly linear relation exists between the average size of the debris generated during the compressive...
Pre-Evaluation of Hydro-Demolished Concrete Surfaces by Dulled Core Testing
Elimination of Ruts at Intersections by Means of An Inlay/Overlay Made of Steel Fibre Concrete
To the North of Gent there is an important harbour and industrial zone. Because of the heavy traffic on the road connecting Gent and Zelzate (R4, section J. Kennedylaan), deep ruts have formed in the asphalt pavement, mainly at the junctions. In order to repair these ruts in a durable...
The Behavior of Concrete Block Pavements
In 1981 to 1985 and 1993/94 static and dynamic tests on block pavements were carried out on a 1:1 scale at the professorship of Road Construction at the Technical University of Dresden. The pavements were loaded with a plate bearing test equipment (approx. 0.7 N/mm 2) with a static stress...
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...
Fine-Grained (Sand) Concrete for the Construction of Cement Concrete Road and Airfield Pavements
The problem of using fine-grained (sand) concrete instead of the "classic one in the construction of road and airfield pavements is analysed. In sand concrete the coarse aggregate, crushed stone or gravel, are substituted by natural sand or a blend of natural sand and screenings 0.5 (10) mm. The use...
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...
Influence of Cement on the Durability of Concrete Pavements
Cement for concrete pavements has to meet special requirements. Besides cement properties which influence the fresh concrete, the cement is of great importance for the durability of concrete pavements. If the joints in the young concrete are not sawn early after paving, cracks can form in the pavement. With cracking-frame...
Construction and Evaluation of Pavements with Porous Concrete Bases
Two test sections were constructed with a base course of porous concrete under the emergency lane of a motorway. This base composed of new aggregates or recycled aggregates, has the strength of a cement treated base and the function both of bearing capacity and drainage. Mixed in Plant and placed...
Curing of Concrete Pavements to Control Thermal Stresses
The main goal of curing is to protect the young concrete against drying out. These investigations indicate, that concrete temperatures during the first day of hardening are decisive for the magnitude of thermal stresses of the hardened concrete and the related cracking risk. High thermal tensile stresses occur, if the...
Design and Construction of a Concrete Pavement on Compressible Muds
This paper deals with the design, construction and performance of a freeway section over a thick layer of compressible mud. Halfway on the Madrid to Zaragoza freeway, in the valley of the Jalón River, several very soft clayey deposits were found, originated by endorreic drainage basins. The ground treatment systems...
Construction of Concrete Pavements on Bituminous Draining Bases
In January 1 9a9 1ro, ad section of 12 km, the access to Zaragoza from Huesca (Spain), was opened to the traffic. Works presented two main technical singularities in Spanish road design and construction. The first one was the introduction in Spain of the construction of rigid pavements on bituminous...
Concrete Overlay Thickness Design Based on FWD Deflections for Airports
Since the overlay thickness must be decided considerinq the structural condition of the existing pavement, FWD was introduced to evaluate the mechanical properties and to obtain input data for the overlay design. In the case of concrete overlays for concrete pavements, the overlay thickness depends on the existing slab thickness...