Marsh funnel Test as an Alternative for Determining Liquid Limit of Soil

Abstract

The liquid limit of a soil is a fundamental  index property that is routinely used in engineering practice  to predict the behavior of cohesive soils. The Casagrande and  fall cone test methods are the standard methods used to  determine liquid limit. However, these methods require  significant sample preparation, are time-intensive, and are  subject to a range of errors dependent on the experimenter’s  technique and experience. The study presented here  investigates the feasibility of an alternative method for  determining the liquid limit of soil. The nature of the  definition of liquid limit suggests a relationship between  viscosity, a mechanical fluid property, and the liquid limit.  Accordingly, this study investigates the relationship between  liquid limit, determined by Casagrande method, and the  Marsh Funnel viscosity. The Marsh Funnel viscosity test  produces an indicator of absolute viscosity by observing the  time required for a fluid to flow through a calibrated funnel.  Four different types of soil were prepared at a range of  successively decreasing moisture contents. The liquid limit  of the material was taken as the moisture content at which  the Marsh Funnel viscosity approached infinity (stopped  flowing). This value was then compared to the liquid limit  determined using the Casagrande method in order to make  preliminary conclusions regarding the suitability of using the  Marsh Funnel test as an alternative method to determine  liquid limit.