ECONOMIC EVALUATION OF VARIOUS TYPES OF PAVEMENTS

Abstract

Economic enelysis (appraisal, eveluation, assessment etc.) are increasingly being applied as port of the over-all planning end policy making processes. The mein objec-tive of the economic analysis is to compare the mutually exclusive schemes end select the most attractive one. For highway projects, it pleys a key role in preparing the road development piens at netionel, regional or local level and phesewise investment planning, construction, maintena-nce, rehabilitation and thus sharpens and improves the decision making. According to the law of demand of economics, as the cost of materiel, construction end maintenance per km of pavement (price per unit) decreeses more kilometers (quantities) can be constructed end maintained. LAW of demand also applies to the substitutability of the pavement material systems for one another. If one materiel system for one km of road becomes costlier other available good substitute (material system) would become relatively more ettrective or productive i.e. marginal rete of substitution for substitute is low. Hence using substitutes, the engineers hove choices end by recommending, for a good substitute meterial system, scarce resources can be conser-ved end utilities can be maximised. However, one should keep in mind that substitutability hes got certain limitations. —iii- -iv- In this dissertation an attempt has been made to present e framework mainly for the alternative types of pavements. The procedure has been exemplified by giving the economic evaluation of typical pavement sections anelysed for a perticulsr set of conditions. After desig-ning the pavements, as per IRC end other standard speci-fications for e renge of situation, initial cost of construction, maintenance cost and total costs for an evaluation, period of thirty yeers htve been arrived at covering a wide range of substitute material systems. Appropriate values of material costs, their evailebilities, rates of interests etc. have been taken into account. Sensitivity enelysis has also been done to take into account the uncertainities. A set of nomograms has been preprred for various types of pavements for quick calcula-tions of costs end these can be used as reedy references. In economic analyses costs of binding materials end main-tenence hrve been found to be the most crucial perimeters. Findings of this study also show that in almost all calculations, cement concrete (C.C.) and Steel Fibre Reinforced Concrete (SFRC) types of pavements are relatively cheaper than flexible type of pavements. Among the other types of pavement the relative standings are bituminous concrete, semirigid end polymer reinforced (geogrid) types of pavements. Validity of these conclusions will however depend upon the set of particular conditions. C.C. end S.F.P:C. types of pavements require high Innis' costs end low maintenance cost end stage const-ruction is not fersible. These pavements have better roughness values end riding quelities which turtler reduces the opereting costs. S.F.R.C. types of pavements require less thickness, less number of joints, have high design life and creeks ere arrested. Rapid increase in cement production in India, easy evailebility, low esceletion in prices, aveilebility of skilled manpower end mechineries necessitete thet time hes come when highway engineers should go fcx these attractive substi-tute prvement meter's' systems end thet too especielly for the roods of primary system e.g. Express lays, Rational highways. Polymer reinforced types of pevements which give sevings in materiels, time, energy end maintenance ere elso expected to cost less if the basic meteriel costs ere brought down end then these will be more