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...
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...
An Acquisition System For Monitoring Polyfunctional Composite Pavements PCP
The criteria are presented for the choice of the proper instruments to detect strains/ stresses and temperatures on a stretch of composite concrete motorway paving. The following are described: project, implementation and assembly of the entire acquisition system broken down in two parts. The first is designed for controlling low...
Roller Compacted Concrete RCC Pavements For Motorways and Main Highways the Spanish Practice
First applications of roller compacted concrete (RCC) pavements on main highways took place in Spain in 1984. Since this year, RCC pavements have been employed in a large variety of works, their total surface exceeding 1.600.000 m2 by the end of 1989. Up to now, their behaviour has been very...
Restraint Stresses in Young Concrete Pavements
Under adversè conditions, the restraint stresses of young concrete pavements can cause the forma-tion of random cracks. In order to determine theparameters which influence the formation of thesestresses a full-scale experiment including sixdifferent test sections was performed. The experi-ment showsthe greatinfluenceof climaticconditionsin the days after placing the concrete. The analy-sis...
Some Theoretical and Practical Aspects of the Use of Fly Ash in Lean Concrete
Until a few years ago, interest in the incorporation of fly ash into lean concrete was rather limited. A study conducted in the laboratory has demonstrated some of the advantages of the technique and shown that the optimum dosage is of the order of5 %. In Belgium, mixtures of this...
Optimization of Surface Characteristics of Cement Concrete Roads
The surface properties of a road pavement must fulfill a long list of requirements. Recently this list has been extended to include acoustic properties. Roughness is characterized by micro-, macro- and megatexture. The results of measurement of skid resistance and road-tire noise are discussed. Possibilities for further optimization of the...
The Application of Foamed Concrete For Pave~1ent Structures
In areas with a low bearing capacity of the soil it is very hard nd expensive to manage and maintain the road system. In eneral the common pavement structures are not able to resist uring its lifetime the deformation of the subsoil caused by the eavy weight of pavement structures....
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...
Very Thin Surfacings For Improving Skid Resistance of Concrete Pavements
This paper describes work on the skid resistance properties of some fine aggregates available in Indiana, as an attempt to improve the driving safety characteristics of concrete pavements. In this work the British Polishing Machine and the Portable Skid-Resistance Tester were used for laboratory evaluation of some mortar mixes. Aggregates...
Structure Analysis of Roller Compacted Concrete Pavement
Roller Compacted Concrete Pavement in Japan has progressed rapidly today because of its simplified paving method and early opening to traffic. Structural properties of RCCP are required to be investigated to establish design method of this pavement. Load response after paving and strain due to base course friction were measured....
New Design Method and Fatigue Analysis of Rigid Pavements with Variable Thickness
A new process for the structural plate analysis has been presented that is based on the condition of stationarity of total complementary energy (equilibrium model) instead than on the condition of the stationarity of the total potential energy (con-gruence model) as usually done. Each of the two processes, asregards to...