Lime stabilisation of highly compressible surface from soils in ex-Lake Texcoco, Mexico

Abstract

Improving soil strength by physical and chemical methods is a common practice in geotechnical engineering. This study investigates chemical stabilization of soil with calcium oxide, CaO, to modify the physical and chemical properties of clay materials, which can rapidly transform a material with poor mechanical properties into one with favorable properties for different surface working conditions and good short-, medium-, and long-term geotechnical behavior and its effects on the environment. Effects that affect the site and other regions beyond the airport construction polygon. The main advantages measured are. The mitigation (27.6%) of the exploitation of borrow pits, the use (81.1%) the natural materials from site, and the mitigation (11.1%) of the transport demand. The analyzed materials are lacustrine clay soils (cohesive soils) with low strength, high compressibility, and moisture contents of 55%, 100%, and 170% from ex-Lake Texcoco in the basin of the Valley of Mexico. In this study, the authors performed Atterberg limits tests, compaction tests, unconfined compressive strength (UCS) tests, California bearing ratio (CBR) and expansion tests, Eades and Grim tests, and quantitative chemical analyses by X-ray fluorescence (XRF) and X-ray diffraction (XRD). The optimum lime contents for the analyzed samples were 5% and 15%. The UCS of the mixtures was analyzed for curing periods of 7, 14, 21, 28, and 69 days, which resulted in a final compressive strength (UCS) greater than 2000.0 kPa, CBR >50%, and expansion in-situ stabilized soil in 2015 and 2016 were studied.