Quality assurance (QA) in its traditional meaning is based on very detailed, in general prescriptive design and construction standards, on standardi-zed conformity criteria for all construction mate-rials and on generally accepted rules for good cons-truction practice. This basis allowed to limit QAon control tests and acceptance decisions for in-termediate or...
Novel Developments in the Quality Assurance of Road Construction Projects
The Influence of Size and Hardness of Sand Particles and their Proportions on the Skid Resistance of Cement Mortars
irnestone and emery sands divided into 6 fractions, were used ,cast cement mortar specimens in PSV moulds. After 28-day ater curing the specimens were subjected to accelerated ilishing and their Skid Resistance Value (SRV) was measured ith the pendulum tester. Specimens of 100 % limestone or )0 % emery sand,...
Dependable Production of Air-Entrained Concrete with High Resistance to Freezing and Thawing in the Presente of De-Icing Salt For Road and Bridge Construction
To ensure that concrete has a high resistance to freezing and thawing it must contain small air voids which are produced by an air-entraining agent and which must be present in sufficient quantities to match the amount of fine mortar. The limits for the air content of unset concrete and...
The Development of Concrete Safety Barriers in France
The use of concrete safety barriers is currently increasing considerably. The area of use, limited for a long time to urban or suburban carriageways, has now spread to the whole of the road network. The appearance of sites longer than 10km had led companies to work in a different manner,...
Specific Deterioration of Construction Joints in Continuously Reinforced Concrete Pavements_ Under Very Hot Weather Conditions
Generally due to an unsufficient vibration, the concrete around the construction joints may contain cavities, especially under the reinforcement. When very hot weather conditions prevail, these deficiencies may cause important deteriorations, possibly with mere fragmentation of the concrete around the joint. As there are over 5.000 construction joints on the...
Resurfacing Flexible Pavements with Thin Layers of Concrete with Steel Reinforcement
This paper describes the studies, reports and experimental sections related to this new type of pavement, not conventional, composed of a thin concrete layer, but with a steel reinforcement, in sufficient quantity to resist the traffic loads. The description goes back to the first studies and tests carried out inthe...
Various Construction Techniques in North America_ Asia and Europe Economic Construction with Roller-Compacted Concrete
Clients and contractors all over the world are aiming to reduce construction cost by using less expensive construction material and applying new, more economic construction methods. This is a continuous challenge to the manufacturers of construction machinery to modify existing machines or develop new ones to meet the contractor's requirements....
The Design and Maintenance of Contraction Joints Behaviour of the Namur Test Road After 10 Years of Traffic
This article describes the behaviour after 10 years of service of the test sections constructed in 1979 on State road N 4 in the Belgian province of Namur, The object of this experiment, is to compare various types of contraction joint on the same site and under the same conditions...
Modern Construction of Concrete Pavements For Expressways in Spain
In this paper, basic characteristics of concrete pavements constructed in Spain during the last years, corresponding to the General Highway Plan 1984-1991, are described. The main solutions adopted to get a concrete pavement with high strength and appropriate texture are an~)ed. The solutions used in the construction in cold weather...
Noise Reducing Concrete Surface. a Model For Assessment
me of the attributes required from a pavement is a noise redu-ing effect. But an optimization of this attribute without con-idering other important requirements as stability and pos-ibilities for patching, reinstatement and environmentaliaintenance is contrary to all national economic principles. Inact it is the road user who is running the...
The Brite Project on the Freeze/Thaw Durability of Concrete Block Paving
The prime objective of this programme is to develop an ac-zelerated freeze/thaw performance test that relates reliably tofield performance.Samples of 40 experimental block mixes have been placed onone or more of 5 exposure sites. Data from meteorologicalstations on these sites are being used to model the relationshipbetween ambient conditions and...
Payement Management For Concrete Pavements
The Illinois interstate highway network includes over 1700 centerline miles of jointed concrete and continuously reinforced concrete pavements. The pavements were constructed beginning in the 1950's through the 1980's and represent a wide range in designs and traffic loadings. This large highway network is now requiring extensive rehabilitation work as...