Long-term Performance of Loess-cement

Abstract

In Bulgaria, comprehensive research and practical experiments of loess-cement have been started in the sixties of the last century in the Geological Institute of Bulgarian Academy of Sciences and later an extensive application has taken place mainly in foundation works and irrigation facilities. The construction of soil-cement impervious screen at the bottom of the irrigation levelling reservoir of the Lom Agricultural Testing Station in the late sixties of the last century was one of the earliest applications of the loess-cement. Recently a comprehensive analysis of the microstructure, physical and mechanical parameters of the loess-cement from this impervious screen was executed aiming to assess the long-term performance of the soil-cement after more than 50 years of curing at field conditions. The current paper discusses the main outcomes and findings of that investigation. It was found that the phase transformations of the C–S–H of the cementitious mass in the inter-aggregate pore space resulted in denser microstructure and higher strength of the loess-cement after long-term curing.