Some experiences on the stabilization of Irish peats

Abstract

This paper presents the findings of a study into the engineering properties of two peats from the Irish Midlands that were mixed with various binders to form a stabilized soil. The study comprised an investigation of the increase in unconfined compressive strength over time achieved using different binders for both peats and a comprehensive series of triaxial and compression tests on one peat when mixed with cement. A stabilized structure (i.e., a stabilized surface layer and a stabilized column) was tested in a large testing chamber in Trinity College to compare the laboratory parameters with those interpreted from the results of the large-scale test. The study showed that the engineering properties of the peat were considerably improved when mixed with some binders, however the degrees of improvement were markedly different for the two peats that had similar organic content. The formation of the stabilized soil structure within the testing chamber significantly reduced the amount of settlement when compared with that interpreted for the untreated soil, and the rate of consolidation was accelerated. A finite element analysis of the recorded behaviour in the large testing chamber showed good agreement between the simulated and the experimental behaviour.Key words: peat, cement, stabilization, compressibility, column.