concrete pavements for airfields

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CONCRETE PAVEMENTS FOR AIRFIELDS1. INTRODUCTION2. THEORIES OF DESIGN OF RIGID PAVEMENTS2. 1. INTRODUCTION2.2.THE THEORETICAL SOLUTIONS2.2.1.Westergaad Solution2.2.2.Picket Solution2.3.THEAPPROXIMATION SOLUTIONS2.3.1.Finite Difference Method2.3.2Layered Elastic Systems2.3.3.Finite Element MethodGLOSSARYREFERENCES:Concrete pavements forAirfields.1. IntroductionAnalysisof the structuraldesign of airportpavementsconsistsin part of determiningboth the thickness of therigidpavementitselfand the thickness of the rest componentparts of the pavement structure (sub-base).Thisis a complicate problem, in which involvedtheoretical,applied,experimental, andnowadayscomputational Mechanics.There area numberof factorswhichaffectthe ability of a pavement to provide satisfactoryservice. These include:the quality of the pavement foundation (sub-grade), the magnitudeand characterof theaircraftloadsto be carried, the volume trafficthat meansloads repetition, the concentrationof traffic incertainareas, the quality of material used in construction(concrete slabs,sub-base) and the climatologic conditions.Themodulus of elasticityof a concrete pavementis much higher than thatofthesub-gradeofsub-basematerial, a major part ofthe load carryingcapacity is derivedfrom the beam action of the slab.The stresses producedinrigidpavementscan berelated to the followingbroad categories: Curlingstressesdue to temperaturedifferentialthroughthe thickness of the slab;andwarpingstressesto differenceinmoisture. Frictional stressesdue to uniform temperature variations. Infiltration stressesresultingfrom the filteringdown of foreignmatterinto thejoint, or from pumpingaction where thesub-gradematerialis forcedup into thejointby the jetting action o pumpingwater. Load stressesdue toexternallyapplied loads.2. Theories of design ofrigid pavements2. 1. IntroductionIn reality, the numerous so-called theories ofrigid pavementdesignall springsfrom a single theory,the theory of elasticity.

Plates theoriesmoderately thickthinvery thin

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