DEVELOPMENT OF CAD BASED ANALYSIS OF COMPOSITE PAVEMENTS

Abstract

The automobile industry in India is under going quick transformation in terms of technology fleet mix and extent of production. But modern vehicles need modern roads. The present roads can not cope up with fast and fuel-efficient vehicles. These roads will severally deteriorated by the heavy axle loading, their repetition and ill maintenance, which aids to the further problems. Concrete is probably the most widely used man made constructional material in the world. Due to its specialty of being cast in any desirably shape, it has replaced the old constructional techniques of stone and brick masonary. Plain concrete has qualities of flexibility, resilience and ability to redistribute stresses. But it is considered a brittle material as it fails in tension due to formation and propagation of internal microcracks. The use of small-embedded reinforcement generally termed as "fibres "has been recognized as a means to improve the tensile strength and other properties of plain concrete. The addition small closely spaced and uniformly, dispersed, discrete steel fibres, to concrete, substantially improve its engineering properties such as flexural strength, fracture toughness, resistance to fatigue, impact and shock loading. Various composite pavement section can be constructed by using various layer of different material, such as plain concrete, bituminous concrete, lean concrete, SFRC, cement treated base, FLY ASH, untreated granular material, bituminous stabilized base etc. " A composite pavement is a pavement comprising of multiple structurally significant, layers of different, and some time heterogeneous composition. In fact these are pavements where different materials are used at different depths of the pavements, the choice being made on stresses at the layers and strength of materials. In addition to economy, the construction of composite pavements require less maintenance cost and performance of these pavements has been reported to be better than conventional pavements. Software COMPANA has been developed in VC++ development environment, which is a graphical user interface based programming using the Microsoft foundation classes. VC++ language is a part of the Microsoft Visual Studio. It can run only in window environment. After developer studio starts, a window appears. The main areas of this window are workspace, output pane, editor area and Menu bar. Workspace also has three parts: 4 (1) Class View (2) Resource view (3) File View Output pane, where compiler progress statements, warnings, and error messages and where the visual C++ debugger display all the variables with their current values as one step through one's code. This software was developed to determine the safe stresses at edge and corner of layers of the composite rigid pavement and other design parameters details of joint spacing, dowel bar and tie bar like diameter, length and spacing etc. Software also evaluates the expenses on the construction of composite pavement. It also gives, 2d image of composite pavement components. There is a facility available in the software to display graph between stresses and thickness of composite pavement or factor of safety and thickness of composite pavement layer. This software is easy use with the help of print command, which is available at the same window; user can take the print out of result. India has been divided in six zones according to the temperature variation for the pavement thickness from 10 to 30cm. Because temperature has significant effect on the pavement. Due to it warping stresses is developed. For considering this effect table 1 is given at the end of this thesis in appdix-1 has been fitted in this software. Software has option of variable loads and type of composite pavement as PCC, SFRC, FFC or its combination because if pavement types changed its modulus of elasticity, Poisson's ratio flexural strength has been changed. Software is user friendly and interactive due to easy in use. It can be used in the actual field of the civil engineering application. After doing some modification in the software it will also useful in the airfield design.