Experimental investigation to study the effect of reinforcement on strength behavior of fly ash

Abstract

Stabilization of the subgrade soil is a primary and significant phase in highway construction. In constructing a flexible pavement subgrade, soil investigation is an important parameter, as the load is transferred to it under a repetitive vehicle load. Subgrade soils with low strength of bearing are incapable of bearing heavy loads and are considered unsuitable for construction. The author proposed a solution for the weak subgrade of flexible pavements in this paper. This study aims to address weak subgrade issues by using fly ash reinforced with reinforcement. The California bearing ratio test (CBR) unsoaked was performed on the fly ash positioning with square and circular reinforcement patterns in the center of the loaded area. The test was performed using different reinforcement of diameters 1 and 2 and twisted 2 mm (1 mm diameter reinforcement overlap, then it was twisted over each other to make a 2 mm diameter twisted reinforcement). The CBR value for plain fly ash is found to be 14.64%, and the maximum CBR value for square and circular reinforcement is 34.89% and 24.23%, respectively. The percentage increase in the CBR value for square and circular reinforcement is to be 138.31% and 65.50%, respectively. The study found that the reinforcement spacing pattern affects the subgrade bearing capacity. As the reinforcement spacing decreases, the bearing capacity of the fly ash increases with the increment of reinforcement diameter. This study is important for subgrade soil strengthening since this fine reinforcement has increased the bearing capacity of poor soils.