ABSTRACT
The essential input parameter required in Barron’s theory for the design of vertical drains is the coefficient of horizontal consolidation, ch . The possible reasons for the difference in the values of ch , determined using radially inward test and outward test, is evaluated using an instrumented consolidation cell of 150 mm diameter. The paper also discusses the different methods of determining the values of ch based on radial consolidation tests with inward flow. The extent of the smear zone is an important parameter that characterises the smearing effect. This paper describes this effect in terms of smear ratio (i.e. the ratio of the diameter of the smear zone, ds, to the diameter of the rain, dw ) on the consolidation characteristics. Further, this study discusses a non-graphical approach involving non-linear regression analysis to predict the ultimate settlement and ch based on the time-settlement data obtained in the preloading projects.
