The strength of soil–industrial by-products–lime blends

Abstract

The aim of this study is to assess the strength controlling parameters of a sandy soil (Botucatu residual soil (BRS)) treated with industrial by-products (basaltic powdered rock (PR) or coal fly ash (FA)) and lime, as well as to show that the porosity/volumetric lime content (η/Lv) plays a fundamental role in the assessment of the target strength. The controlling parameters evaluated were addition of industrial wastes, quantity of lime, porosity and η/Lv. The unconfined compressive strength (qu) increased non-linearly with the amount of lime and decreased with porosity for all studied mixtures. Similar equations were found relating qu to η/(Lv)0·12 for BRS–lime, BRS-PR–lime and BRS-FA–lime mixtures. Tests of potential reactivity of siliceous materials with alkalis on the materials studied indicated that the higher amount of dissolved silica in the alkaline environment of the FA, when compared with the BRS and the PR, was responsible for increasing the number of reactions with the lime and consequently increasing the strength for BRS (25% FA)–lime mixtures, when compared to BRS–lime and BRS (25% PR)–lime blends.

Prognose der Festigkeitsentwicklung zementbehandelter Böden mit dem Porosity/Binder‐Index

“…Die Gl. und wurden erfolgreich im Zusammenhang mit der Bindemittelbehandlung von Sanden , sandigen Tonen und schluffig/tonigen Sanden und bei feinkörnigen Böden wie Schluffen und Tonen angewendet. Das Konzept wurde für unterschiedliche Bindemittel , Mischungen aus Bindemitteln und Fasern , Mischungen aus Boden, Dachziegelbruch und Zement und für die im Erdbau üblichen nicht ideal homogenen Mischungen aus Bindemittel und Boden bestätigt und für ideal homogene Mischungen auf die Prognose der Festigkeit zu unterschiedlichen Prüfzeitpunkten erweitert .…”

Undrained Shear and Pore Space Characteristics of Treated Loose Sands with Lime-Activated Zeolite in Saturated Settings

“…According to Consoli et al [17], a small portion of lime is enough to generate a significant rise in strength. Thus, four different lime percentages were used in this part, with the minimum amount of lime set at 3% of the mass of dry soil [17,18,19,20]. The adopted zeolite percentages were chosen based on a few pertinent studies.…”

“…Having these contradictory observations at hand and comparing the results of 7 and 28 days cured samples indicates that the main reason for these differences could be related to the imbalance of the incorporation of zeolite and lime into the pozzolanic reaction process. This leads to an uneven distribution of cemented particles and the reduction of final strength [20,28]. For example, in samples with 4% lime, as shown in Fig.…”

Geotechnical Characteristics of Fine-Grained Soils Stabilized with Fly Ash, a Review

“…A large amount of fly ash is disposed to landfills or placed in storage [30][31][32], thus the disposal/storage cost of fly ash increases every year. The disposal space and disposal cost of fly ash can be minimized by increasing the use of fly ash in industry [26].…”