Concrete made with a superplasticiser has been used in Germany in the field of paving since the middle of the seventies. If these concretes of high workability show a high strength at a young age, they are called high early strength. These concretes can be subjected to high loading on...
Ultrasonic Method in Concrete Road Testing
To determine the concrete strength in road surface the authors have applied an ultrasonic method. In this method ultrasonic transducers are imposed to the upper surface of the pavement slab. The distance between the transducers is constant. Next propagation time of longitudinal ultrasonic wave is measured. The time of propagation...
Load Transfer Restoration LCPC Freyssinet Connector
The LCPCIFREYSSINET slab connector is an innovating device allowing load transfer restauration of concrete roads submitted to pumping effects. It is constittïed by two synietrical half-shells in cast iron glued to a central elastomeric pad and contains an adjusted steel-pin which slides freely within housings machined in the shells, making...
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....
A New Design Method For Control of Cracking in Continuously Reinforced Concrete Pavement
Reinforcement stress and crack width has been in-vestigated in full scale experimental pavement ofContinuously Reinforced Concrete Pavement forthree years. The validity of designequation for pre-dicting crack width distributed through the thick-ness of the slab and reinforcement stress etc.,which is based on bond stress -slip relationshipconsidering the effect of both concrete...
A Contribution to the Study of Joints on Concrete Pavements
vlaterials used as joint sealants on concrete pavements are zenerally classified in: - Preformed sealants. - Field molded sealants. l'his work shows the demanded characteristics for preformed .ealants and field molded sealants. The last ones are divided in :wo types: thermosetting -two component systems- coldap-rlied, and thermoplastics --one component- bot...
Economic Analysis of Cement Fly Ash Bound Materials
In order to design a cement bound mixture for use in base/sub-base pavement layers, it isusually re-quired to obtain a certain minimun strength value.Ifonly one type of binder isused, the problem hasonly one restriction and one variable, so, one onlysolution. However, if more binders are added tothe mixture, asit happens...
Developments in Noise Redution of Concrete Roads in the Netherlands
In the Netherlands experiments have been performed recently :onceming noise reduction on concrete roads. Three pos-.ibilities are being investigated:I. Top layer of no-fines porous concrete.~. Surface of washed dense concrete.. Dense concrete with fine-grained epoxy surface treatment. noise emission level slightly higher than on porous asphalt,iut much less than on...
The Passage of State Roads Through Built-Up Areas. Applications of Concrete Block Pavements
In the eighties, a campaign was set up in Belgium in view of the rearrangement of the state road sections which are passing through built-up areas. These projects were meant to improve the road safety and the viability along these cross town links. Efforts were made to come to a...
The Potential of Thinner Concrete Pavements: Evidence from Accelerated Testing
Overseas thin concrete slabs have been used successfully and have been shown to be economic. To evaluate the suitability of this type of construction under South African conditions, four experimental sections were constructed to evaluate the interaction of slab thickness and subbase thickness and quality. The sections were trafficked with...
Proposed Test Method For a Procedure to Stitch Longitudinal Weakened Plane Joints in a Plain Jointed Portland Cement Concrete Pavement Where Tie Bars Were Ineffectivel Y Located During Construction
The method used to conduct pull-out tests on tie bars cast into the edge of an existing concrete pavement is described. The test results are used in conjunction with a simple statical procedure to design an economical system for stitching sections of longitudinal weakened plane joints in a plain jointed...