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Restraint Stresses in Young Concrete Pavements

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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

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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

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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

Highways, Local Government Members Only

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

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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

Highways, Local Government Members Only

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

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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

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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...

Lime-Cement Stabilization of Wet Cohesive Soils

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When treated with lime, wet cohesive soils granulate and be-ome more workable, thus allowing easier subsequent incor-oration of cement.'he effects of pregranulation with lime on various aspects ofement stabilization were investigated: compaction. CBR bear-19 capacity, strength values, durability, the effects of differentariables such as density and moulding moisture content. Theitter...

Study of Long-Lasting Materials and Conventional Paints on Concrete Surfaces

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Due to the increase of concrete use in road cons-truction, the report examines the influential fac-tors on the three most important properties in roadmarking, above all on concrete pavements.The analysed properties are:- Night visibility.- Day time visibility.- Skid resistance.The study makes a comparison of two systems:two components system (plastic of...

Characterization by Means of Some Fracture Mechanics Parameters of the Concrete Pavement of the By-Pass Between Al and A2 Italian Highway

Highways Members Only

This work reports the results obtained with the three point bend tests (TPBT) carried out on beams made up of the concrete used for the construction of a by-pass highway and, by comparison, of medium (50 N/mm2) and high strength (98 N/mm 2) laboratory concretes. Typical parameters of fracture mechanics,...

Dynamic Deflection Measurement on Rigid Payements Using the Falling Weight Deflectometer

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Deflection caused by a load is an important measure for the bearing capacity of rigid pavements, too. For this reason the deflection on a variety of sections with different constructions has been measured in the Federal Republic of Germany. For these measurements the «Falling Weight Deflectometen> was used, developed by...