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Constructing on soft clay entails engineering challenges, such as significant volumetric changes; hence, stabilizing such problematic soil is essential. Since using lime in stabilizing soil is not recommended in some regions (e.g., Manitoba, Canada) due to some environmental concerns, there is a pressing need to explore suitable alternatives. This study investigates the efficiency of stabilizing soft clay using nano-modified cementitious binders (cement, slag, and nano-silica), reinforced with a new class of fibers (basalt fiber pellets). The mechanical and durability properties of the mixtures have been tested in terms of California bearing ratio, unconsolidated–undrained triaxial stresses, and freezing–thawing resistance. Thermogravimetry and scanning electron microscope analyses were performed to interpret the bulk trends. The results showed significant improvement for soft clay specimens stabilized with the nano-modified cementitious binders and reinforced with the pellets. This demonstrates the potential of the proposed reinforced binders for field applications involving the stabilization of soft soils. [ABSTRACT FROM AUTHOR]

The longevity of a single 22.4 Mg·ha−1 application of dolomitic limestone at four northern hardwood stands was evaluated over 30 years (1986–2016) to determine whether changes in soils, foliage, and tree growth were sustained on the unglaciated Allegheny Plateau in northern Pennsylvania, USA. In limed plots, soils, sampled to 45–55 cm depth, and sugar maple (Acer saccharum Marsh.) and black cherry (Prunus serotina Ehrh.) foliage had significantly (P ≤ 0.05) greater concentrations of calcium (Ca) and magnesium (Mg) through 2016 compared with samples from unlimed plots. Ca and Mg capitals (g·m−2) in the Oi through A horizons combined were greater on limed plots than unlimed plots, largely due to increases in the thickness and nutrient concentration in the A horizon. Over 30 years, sugar maple basal area increment (cm2·year−1 BAINC) was greater in limed plots (30.6 cm2·year−1 vs unlimed 13.3), American beech (Fagus grandifolia Ehrh.) BAINC was unaffected by lime application, and black cherry BAINC was reduced in limed plots compared with unlimed plots. The sustained effect of this one-time lime treatment shows the strong role of efficient nutrient cycling in forests and suggests that the benefits over a substantial portion of a stand rotation may increase the feasibility of operational liming. [ABSTRACT FROM AUTHOR]