Impact of agricultural waste on the shrink–swell behavior and cracking dynamics of expansive soils

Abstract

Purpose The swelling characteristics and cracking of expansive clayey soils usually lead to their low yield, and as a result, large areas of expansive soils remain uncultivated and unproductive. There is a need for the development of simple, low-cost technologies which will bring these soils into production. The amendment of expansive clayey soils with agricultural waste products is a key goal for enhancing their production potential. Therefore, a study was conducted to evaluate the ameliorative effects of crop residues on the physiochemical and mechanical properties of expansive clayey soils. Method In this study, the potential soil amendments used include uncharred rice husk, rice husk biochar, uncharred sugarcane bagasse, and sugarcane bagasse biochar. The biochar was pyrolyzed at 450 °C. The amendments were applied into the soil at four applications rates: 0, 2, 5, and 10% by weight of soil (w/w), respectively. The mixture was then incubated in a glasshouse for 280 days. Results Charred and uncharred rice husk and sugarcane bagasse improved the physico-mechanical properties related to soil expansion. The liquid limit (LL), plastic limit (PL), plasticity (PI), coefficient of linier extensibility (COLE core), volumetric shrinkage (VS), fissures' dimensions, and crack area density (CAD) of the soil decreased with an increase in treatment application rate. On the contrary, saturated water content increased with an increase in dosage. Conclusions 10% level of amendment application resulted in significantly improved soil properties than either 2% or 5% doses. Moreover, 2% level of amendment application is more preferable than 5% according to feasibility and economic point of view.

Biochar with Alternate Wetting and Drying Irrigation: A Potential Technique for Paddy Soil Management

“…With intermittent drying and wetting conditions, clay minerals expand and become sticky and muddy by absorbing moisture as they get wet; conversely, the formation of desiccated cracks that appeared on the soil surface shrink during the drying period [155]. Soil cracks are crucial from a different point of view, and they allow increased water infiltration also transport the nutrients to the subsoil [156]. For instance, plant roots may physically be damaged by these cracks.…”

Failure Mechanisms and Protection Measures for Expansive Soil Slopes: A Review

“…Agricultural waste materials have also been used for expansive soil modification, with the advantage of increased environmental protection value. Bagasse fiber, bagasse ash, and rice husk can improve mechanical properties such as shear strength and compressive strength of expansive soils and reduce expansion potential and crack development [156][157][158]. In addition, biochar can inhibit the expansive deformation of such soils [159].…”

Implications of crop residue removal on soil physical properties: A review

“…for 10 yr increased liquid limit from 37.5 to 39.1%, plastic limit from 27.2 to 28.5%, and plasticity index from 10.3 to 10.5% (Bhushan & Sharma, 2002). Another study found that mixing rice hulls at 50 g kg −1 with a loam soil and incubating for 280 d increased liquid limit from 37.8 to 39.4%, increased plastic limit from 22.9 to 26.0%, but did not affect plasticity index (Malongweni et al., 2019). In the same study, application of rice hulls at 100 g kg −1 did not affect liquid limit, but it increased plastic limit from 22.9 to 25.1% and decreased plasticity index from 14.9 to 12.7% (Malongweni et al., 2019).…”