Hard shoulders provide space for vehicles to stop in an emergency. They additionally provide space to function as traffic lane to keep traffic moving in the customary number of lanes if part of the carriageways is closed for repair measures. In the case of concrete pavements, the structural design and...
A Contractors View of Concrete Pavements in the Expanding Uk Market Place with Particular Reference to Continuously Reinforced Concrete Road Base
The paper reviews the reasons for continuously reinforced pavement design, and the economics of the choice of paving method. The current UK specification, its limitations and the potential va-riance with European and American specificationsare considered with its effect on the historic UKmarket, together with an opinion of the futuremarket.For the...
Low-Noise Surfacing on Concrete Roads
he Utrecht-Amersfoort motorway (A28) was constructed with onreinforced, lightly brushed cement concrete with dowels. r1easurements taken in 1987 indicated that the level of noise nconvenience to the surrounding area exceeded the legally per-ritted standard. In 1988 a 3,500 m stretch of the road was firstround until it was even, then...
The Chemical Characterization of Admixtures For Cement Concrete
Although the Belgian standards provide for quality control of idrnixtures for cement concrete, it is interesting to complement his information by a more thorough chemical identification. this makes it possible to increase the economic advantages vhich result from their use. nfrared spectrographic investigation, which enables the ategory of basic chemical...
Nature Related Constructions in Rural Districts Wheel-Track Paving with Concrete
In the sixties and seventies it used to be the traditional way to build paved country roads in full width in rural road construction. Economical consciousness, agricultural production zones -in the context of developing better economical systems-forced us to change our views. A very natural path is a wheel-track path...
Evaluation and Maintenance of the Concrete Pavements on the Mediterranean Highway
The Mediterranean Highway has been in service for more than fifteen years, and we can state that the performance of the concrete paving has been overall excellent whether referring to its surface characteristics or its structural characteristics, except for those areas giving support where damage has taken place. The modifications...
Traffic Management Layouts with Improved Capacity For Major Roadworks Narrow Lanes and Tidal Flow Operations
The layout commonly used at major motorway sites in the United Kingdom is the full contra-flow, which carries two traffic lanes in each direction on one carriageway, releasing the other carriageway for reconstruction. To improve operational efficiency, two adaptations of this layout, which operate with a reversible (or tidal) lane,...
Use of Roller Compacted Concrete RCC in Norway
The first Ree full scale testing project in Norway took place in 1981. Since then appr. 260.000 m2 Ree have been placed. The use of Ree in roads in Norway has been directed by the following main principles: 1. Ree shall be a pavement with good bearing capacity, good resistance...
Effects of Temperature and Moisture on Concrete Pavements
During hardening concrete pavements do not have a uniform distribution of temperature throughout the thickness. The calculation of tem-perature stresses has to start from the differencebetween the zero-stress-temperature and the actualtemperature. Itisadvantageous if (for example dueto wet-curing) the zero-stress-temperature is lowerat the top than in the middle of the slab....
Novel Developments in the Quality Assurance of Road Construction Projects
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...
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...