Investigations on Bio-enzyme Stabilized Pavement Subgrades of Lateritic, Lithomargic and Blended Soils

Abstract

The pavement is a structure, which is laid to support the wheel load and to spread the load stress to a wider area on the top of the soil subgrade. The process of changing the engineering properties of natural soil, to improve its strength, bearing capacity and other engineering properties by the addition of suitable stabilizer and admixture is collectively known as stabilization of soil. It is very much essential to improve the soil strength, bearing capacity and other engineering properties to sustain the loads acting on the pavement. By modifying the subgrade soil properties, the crust thickness of the pavement reduces. This paper focuses on the effect of TerraZyme stabilization on three types of major soils available in the coastal Karnataka region. The study deals with the improvement in the engineering properties of these soils after subjecting to TerraZyme chemical stabilization. Initially, tests were carried out to study the mechanical properties like compaction, permeability, unconfined compressive strength (UCS) and California Bearing Ratio (CBR value). Further, the effect additions of TerraZyme chemical in various dosages to soil were observed in terms of their modified proctor compaction, UCS and CBR values. The curing effect on UCS and CBR was investigated. The structural design of pavement for the high-volume roads (as per IRC:37-2018) is proposed by strengthening the conventional subgrade soil layer with TerraZyme and the pavement analysis is carried out. © 2021, The Author(s), under exclusive licence to Chinese Society of Pavement Engineering.