EFFECT OF TYRE FIBRE REINFORCEMENT ON SOIL SUBGRADE AND EARTH EMBANKMENT

Abstract

One of the problems associated with socio-economic development of a country is waste disposal. In engineering and transportation sector one of the wastes generated is scrap tyre and it poses serious environmental problem. India is a vast country with diversity in the soil subgrade. The majority of the soils are, however, weak. So, attempts of highway engineers are always to improve! strengthen the weak subgrade by suitable method. Construction of roads involves substantial investment and therefore proper planning, construction and maintenance of these national assets is of paramount importance. The serviceability contribution of the highway primarily depends upon the quality of the subgrade. The main function of the subgrade is to provide adequate support to the pavement for which the subgrade should possess sufficient stability under adverse condition of loading, climate, drainage etc. Efforts are therefore made to strengthen the subgrade soil by mechanical stabilization, soil-cement, soil-lime, lime-fly ash or geosynthetics to improve its performance. The concept of soil reinforcement with natural fibre materials originated in ancient times. Waste materials such as waste tyres, rubbers, and plastic materials are normally produced in every society,. entering the environment and causing serious problems. These problems may be somehow reduced by findings applications for them in engineering. Highway and earthwork construction is an ideal application of shredded scrap tyres because large volumes of scrap tyres can be used in a single project. In this study, the effectiveness of fibre reinforcement in the subgrade soil has been studied from strength point of view. In the present work, the laboratory studies were 111 conducted on different combination of sandy and clayey soils without and with reinforcement by using rubber tyre fibre with optimum fibre content to study the effect of fibres on variation of dry density, OMC, CBR and modulus of elasticity (E) of soils , the effect of confining pressure on modulus of elasticity (E) value of reinforced soils and the C-(D parameters for different combination soils and the resilient and permanent deformation characteristics of randomly distributed fibre reinforced soils.