Possible relationships between compression and recompression indices of a low-plasticity clayey soil

Abstract

Compression (C-c) and recompression (C-r) indices obtained from the oedometer test are necessary in settlement calculation for clayey soil layers. However, the oedometer test takes a long time to measure the compression of clays. This will lead to a very demanding experimental working program in the laboratory. In the literature, a number of researchers have been looking for a possible relationship between C-c and C-r indices and general characteristics of clays. A number of parameters appear to have an effect on the compression of clays. One of these parameters is overconsolidation ratio (OCR). In this study, the effect of OCR and initial void ratio (e(0)) on C-c and C-r indices of a low plasticity overconsolidated clayey samples, which were prepared in the laboratory under different isotropic pressures, was investigated. Thus, the oedometer tests were performed on these samples, and consequently C-c and C-r indices were calculated. The results indicate that C-c and C-r indices were influenced by OCR and e(0), and, in most cases, a linear relationship between C-c and C-r indices was observed. The results of this research can provide valuable contributions for academics and practitioners.