Effect of Stress Level and Binder Composition on Secondary Compression of an Artificially Stabilized Soil

Abstract

This paper examines the effect on the compressibility of a Portuguese soft soil stabilized with binders, with a special emphasis on creep characteristics. The effects of vertical stress during curing time and binder composition (type and content) on the creep behavior of a sta- bilized material are analyzed with oedometer tests. The results show the decrease of the secondary compression index with the decrease of the vertical stress applied during creep phase and with the increment of the binder content. The best binder type for this soil, in terms of creep be- havior, iscomposedof portland cement and flyash witha dryweight proportionof 75/25, becausethis promotes thedevelopment of secondary pozzolanicreactions.Theresultsalsorevealthatthebindercompositionshouldhaveaminimumquantityofcementtoimprovethecompression characteristicsofthestabilizedsoiladequately.DOI:10.1061/(ASCE)GT.1943-5606.0000762. © 2013 American Society of Civil Engineers. CE Database subject headings: Mixing; Columns; Creep; Soil consolidation; Soft soils; Soil stabilization; Compression; Soil stress. Author keywords: Deep mixing columns; Creep; Secondary consolidation; Oedometer creep tests; Soft soils.