Compressibility Behaviour of Sapric Peat in Double Drainage Constant Rate of Strain (CRS) Test

Abstract

Peat is highly compressible, and it creeps significantly after primary consolidation. Hence, the knowledge of peat settlement characteristics is crucial for sustainable construction on peat. This paper presents the compressibility behaviour of the reconstituted tropical sapric peat specimens obtained via Constant Rate of Strain (CRS) tests by controlling back pressure equal to zero. This technique is found to be helpful to expedite the test. The specimens are compressed one-dimensionally under five different strain rates, from 0.5 %/ hour to 20 %/ hour. Three sets of conventional oedometer tests are also conducted for comparison and verification purposes. The primary compression index values obtained from the specimens vary from 3.021 to 4.146 and are found to be at the lower range for peat in the literature. It is found that the effect of strain rates in the observed range of excess pore water pressure ratio on the compressibility properties of the peat is insignificant.