CORRELATION O STRENGTH PARAMETERS M WITH THE PLASTICITY CHARACTERISTICS OF SOILS

Abstract

"'hen soil is used as construction material, the important property required is the shear strength for particulav condition of the soil in field. The conventional method of determining tho shear strength is by tri-axial testing nhich is quite tedious and time taking. Henco it would be vorthwhile if the shear strength can be determined indirectly from correla-tions ith simple properties of soil like plasticity character-istics. The obvious advantage rill be that those tests done for the classification of soil for the project, can be utilised for estimating the shear strength readily, Lore over correla-tions of shear strength parameters C and 0 vdth the plasticity characteristics help us in understanding the basic behaviour of the soil. In the present investi,ation attempts have been made to correlate the apparent shear strength parameters C and fd (quick test) of cohesive soils %iith their plasticity character-istics, Fifty soils from North India have been collected from different sources, Their 0.L.c., liquid limit and plastic limit have been determined by the usual standard methods. Then the soils vere compacted at O.L.C. at standard Proctor's. At 0..C4, undrained (quick) torts have been performed in triaxial machine aid their c a s.rent cohesion C and angle of internal friction p hive been oh :- ".nod, Then these C and 10, have been correlated :fith liquid limit, pl^;=tic liepit and plasticity index by statistical analysis. (i.v) Of the above trials, the best correlations on the basis of statistical analysis of c:ata, seorais to -)e the correlations of C and 0 with liquid and plastic limits combined.