- journal_title：Quarterly Journal of Engineering Geology and Hydrogeology
- Contributor：Mehrab Jesmani ; Ramin Vaezi ; Mehrad Kamalzare
- Publisher：Geological Society of London
- Date：2012-
- Format：text/html
- Language：en
- Identifier：10.1144/1470-9236/09-060
- journal_abbrev：Quarterly Journal of Engineering Geology and Hydrogeology
- issn：1470-9236
- volume：45
- issue：2
- firstpage：207
- section：Research Articles
There is a general acceptance of constant Cα/Cc ratio (secondary compression index/ compression index) after many investigations made with different soil specimens. Therefore it should be possible to find useful correlations between soil properties and a soil’s unique Cα/Cc ratio. In this paper the secondary compression behaviour of Iranian soils was investigated through the performance of a series of conventional and long duration 1D consolidation tests conducted on undisturbed samples from 11 sites in different parts of Iran. The characteristics of the secondary compression index were examined and the relationship between the coefficient of secondary compression, Cα, and compression index, Cc, was established for each site. Single and multiple regression models to estimate the ratio of Cα/Cc were investigated based on soil properties (liquid limit (LL), plasticity limit (PL), plasticity index (PI) and natural water content (ω0)), and various equations are presented to predict the value of the Cα/Cc ratio of soils.