Effect of industrial wastes and lime on strength characteristics of clayey soil

Abstract

PurposeThe purpose of this paper is to attempt to use two industrial wastes; waste foundry sands (WFS) and molasses (M) along with lime (L) to improve the strength characteristics of clayey soil.Design/methodology/approachIn the first part of the study, the optimum percentages of materials (WFS, molasses, lime) have been found out by conducting differential free swell (DFS) and consistency limit tests on clayey soil by adding various admixtures. The second and third part of the study investigates the compaction behaviour and unconfined compressive strength (UCS) of clayey soil on addition of optimum amount of various materials alone and in combination with each other. Finally, the micro-structural behaviour of addition of optimum percentages of lime, WFS and molasses using Scanning electron microscopic technique has been discussed.FindingsThe laboratory results revealed that the addition of optimum content of lime along with WFS and molasses reduced DFS and plasticity index and increased maximum dry density and UCS values. The microstructural behaviour showed that the presence of lime and molasses filled the voids present in the soil and the addition of WFS helped in providing compact structure, thus improving the strength characteristics.Practical implicationsThe study will be helpful in designing low-cost pavement designs for rural roads.Social implicationsThe adverse effect of waste materials on environment may be solved by using them in improving the strength characteristics of clayey soils, thereby providing healthy environment to living beings.Originality/valueThe study will help to provide low-cost methods to improve strength characteristics of clayey soil along with the use of waste materials; the disposal of whose is a challenging task.