Performance evaluation of stabilized subgrade materials of flexible pavement

Abstract

he use of Bio enzyme to stabilize the subgrade soil is gaining importance in current newlinetrends due to increase in vehicular operation and rapid urbanization in developing newlinecountries. Increase in number of vehicles demands for a better highway having proper newlinedesign, safety and economical. Over all road construction can be made economical by newlinestabilizing the locally available subgrade soil. Extensive review of literature revealed newlinethat much research has been carried on stabilization of soil using admixtures like lime, newlineflyash, GGBS etc however the application of bio enzyme in road construction has newlinebeen less studied. In this study, an approach is made to study the effect of bio enzyme newlineat different dosages on the physical characteristics and strength behavior of various newlinesubgrade soils like red soil, Lithomargic soil and black cotton soil. The effect of newlinecuring at different dosage application of bio enzyme on strength behavior of various newlinesoils has been studied. The mineralogical behavior of conventional and optimum newlinedosage stabilized soil is analyzed through XRD and SEM analysis. Based on CBR newlinevalue of optimum dosage stabilized soil and conventional soil, over all thickness of newlineflexible pavement is designed using IRC: 37-2012 guide lines. The cost estimation of newlineflexible pavement has been calculated for conventional and stabilized subgrade soils newlineas per SHDP guidelines and cost savings have been projected. newlineFrom the laboratory test results, optimum dosage of bio enzyme for red soil, newlineLithomargic soil and black cotton soil dosage d1 200ml/2 m3 at 7 days, 7 days and 15 newlinedays of curing based on compressive strength results respectively is considered. The newlineXRD and SEM analysis of stabilized soil have shown that reduction in void space and newlineenhancement of structural behavior of stabilized soils respectively which is validation newlineof improvement of unconfined strength of stabilized soil compared with conventional