(MDPI, 2022) Seco Meneses, Andrés; Del Castillo García, Jesús María; Perlot, Céline; Marcelino Sádaba, Sara; Prieto Cobo, Eduardo; Espuelas Zuazu, Sandra; Ingeniaritza; Institute of Smart Cities - ISC; Ingeniería; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
This article shows an experimental investigation carried out for the stabilization of a sulfate
soil. The stabilization was carried out in two phases: the first phase was the consumption of the
sulfate present in the soil through its controlled transformation into ettringite. After this, a modified
soil with lower maximum density, greater optimum moisture identified via standard proctor (SP)
test, no plasticity and improved unconfined compressive strength (UCS) was obtained. In the second
phase, the modified soil was stabilized by the use of different additives rich in oxides of calcium or
magnesium, combined with by-products or waste materials containing reactive aluminum or silicon
oxides. As a result, the mechanical strength of the modified soil was improved. In this phase, a
binary binder composed of a magnesium oxide product and ground granulated blast-furnace slags
(GGBS) obtained the highest UCS. The binary binder composed of lime and an alumina filler formed
ettringite in the treated soil. This experiment allowed for the validation of a two-phase stabilization
process and the non-conventional additives used, mainly magnesium oxide and GGBS, even for
high-bearing-requirement pavement layers’ construction.