Assessment of Primary and Secondary Compression Parameters of Tropical Fibrous Peat Using Improved-CRS Consolidation Test

Predicting the long-term compression behavior of peat using conventional Oedometer tests is challenging. This soil exhibits an unusual compression curve shape under conventional load-increment tests. Meanwhile, conducting the conventional single-load test can disrupt specimens due to its sudden load. Alternatively, a constant rate of strain (CRS) test provides a rapid consolidation method by gradually loading the specimen at a small constant strain rate. However, the inability of the conventional CRS test apparatus to measure compression under a constant load limits its applicability in providing the secondary compression curve, which is essential for predicting the long-term compression in peat. To address this issue, an improved-CRS test apparatus was developed to measure compression under a constant load. Tropical fibrous peat was collected from Palangkaraya, Indonesia. The compression curves obtained from the CRS test, which are comparable to those from the conventional Oedometer test, were used to suggest appropriate strain rate ranges for conducting CRS tests on tropical fibrous peat. The results show that the improved-CRS consolidation test provides accurate primary and secondary compression parameters of tropical fibrous peat by using appropriate strain rates, which were categorized based on the coarse fiber content (CFc).