The fundamental cause of frost heave and salt expansion of saline soil is the water condensation and salt crystallization during the freezing process. Therefore, controlling the water and salt content is crucial to inhibit the expansion behaviors of saline soil. Recently, electroosmosis has been demonstrated to accelerate soil dewatering by driving hydrated cations. However, its efficiency in mitigating the salt-induced freezing damages of saline soil requires further improvement. In this study, a series of comparative experiments were conducted to investigate the synergistic effects of electroosmosis and calcium chloride (CaCl2) on inhibiting the deformation of sodium sulfate saline soil. The results demonstrated that electroosmosis combined with CaCl2 dramatically increased the cumulative drainage volume by improving soil conductivity. Under the external electric field, excess Na+ and SO42- ions migrated towards the cathode and anode, respectively, with a portion being removed from the soil via electroosmotic flow. These processes collectively contributed to a significant reduction in the crystallization-induced deformation of saline soil. Additionally, abundant Ca2+ ions migrated to cathode under the electric force and reacted with OH- ions or soluble silicate to form cementing substances, significantly improving the mechanical strength and freeze-thaw resistance of the soil. Among all electrochemical treatment groups, the soil sample treated with 10 % CaCl2 exhibited optimal performance, with a 71 % increase in drainage volume, a 180 similar to 443 % enhancement in shear strength, and a 65.1 % reduction in freezing deformation. However, excessive addition of CaCl2 resulted in the degradation of soil strength, microstructure, and freeze-thaw resistance.

A common physical technique assessed for improving expansive clays is by the addition of natural fibres to the soil. A good understanding of the impact of stabilisation using fibres on the clay soil's constituents, microfabric, and pore structure is, however, required. Mixtures of clay and fibre, regardless of type or extent, can never change the natural composition of the clay. Even the smallest part must still consist of spaces with clay with the original physical properties and mineralogy. This suggests that, although the mixture may show beneficial physical changes over the initial clay soil, its spatial attributes in terms of mineralogical characteristics, remain unchanged. This paper discusses some of the fundamentals that are not always adequately considered or addressed in expansive clay research, aiming to improve the focus of current and future research investigations. These include the process, mechanics, and implications of chemical and physical soil treatment as well as the concept of moisture equilibration.

This paper aimed to determine the attack caused by WCR (Diabrotica virgifera virgifera Le Conte) and its control by chemical treatments on soil and vegetation. The research was carried out in eastern Romania between 2023 and 2024, where two trials were conducted in the experimental field of the Agricultural Research and Development Station Secuieni-Neamt, where three granular insecticides applied to the soil against larvae and three chemical insecticides used on vegetation against adults were tested. Among the granular insecticides tested, the Force G (tefluthrin 15 g/kg) insecticide stood out with the best results, significantly reducing the number of larvae/plant (1 larva/plant) and, at the same time, the absence of the swan neck symptom was also recorded. Regarding insecticides applied to vegetation, the best results were obtained with the insecticide Inazuma (acetamiprid 100 g/kg + lambda-cyhalothrin 30 g/kg), which recorded a very good efficacy in combating adults of the species (95.4%). In conclusion, applying chemical treatments to soil and vegetation is necessary to control the attack by western corn rootworm (WCR).

Plant-based macromolecules such as lignocellulosic fibers are one of the promising bio-resources to be utilized as reinforcement for developing sustainable composites. However, due to their hydrophilic nature and weak interfacial bonding with polymer matrices, these fibers are mostly incompatible with biopolymers. The current research endeavor explores the novel eco-friendly oxalic acid (C2H2O4. 2H2O) treatment of sisal fibers (SF) with different concentrations (2, 5, and 8 % (w:v)) and exposure duration (4, 8, and 12 h). Optimum treatment conditions were achieved through the single fiber strength testing of SFs. The tensile strength of the treated fiber with 8 % concentration and 12 h exposure duration (TSF/8/12) increased by approximately 60 % compared to untreated SF. Fourier transform infrared spectroscopy (FTIR), morphological observation, X-ray diffraction (XRD), and thermogravimetric analysis (TGA) of untreated and treated fibers confirmed that TSF/8/12 has better mechanical and crystallinity behavior than its counterparts. The thermal stability and maximum degradation temperature of the TSF/8/12 are 232 degrees C and 357 degrees C. Sustainable composites were fabricated by introducing the treated SFs (30 wt%) as reinforcement in a bio-based poly (butylene succinate) (bio PBS) matrix. The experimental evaluation of mechanical properties, thermal degradation behavior, and water absorption established that treated fiber-reinforced biocomposites (bio PBS/TSF/8/12) have strong interfacial bonding between constituents that resulted in better thermal stability and decreased water uptake than untreated sisal fiber (USF)based composites (bio PBS/USF). The results of the soil degradation confirmed that SFs expedite the rate of degradation of composites due to the increased availability of hydroxyl groups.

Background The structure of flexible or rigid pavement built on expansive subgrade soil that has a volumetric change is vulnerable to many problems that might cause failure. Pavement and construction became more durable and economical by enhancing the quality of subgrade expansive soil. Solid waste recycling has become very popular recently as a means of attaining sustainable waste management, so using lime kiln dust (LKD), which is a by-product of quick lime production, to treat expansive soil in pavement subgrades. This research describes the effect of LKD on the chemical composition, strength, and swelling of high and low-plastic clay that were extracted from two sites. The minimum LKD required for treating expansive soils was determined by using the Eades and Grim pH test. From tests, it was found that the addition of LKD increased the shrinkage limit by a range (250-500)% and decreased the plasticity and swelling potential by between (50 and 100)% of expansive subgrade soils. The strength according to CBR, increased approximately by 150% for CL soil and 800% for CH soil.Results The optimal percentage of LKD for CH soil is 6%, and for CL soil, it is 2%. The plastic limit increased by 50% for CH soil at 6% LKD. On the other hand, CL soil became non-plastic at 4% LKD. With an increase in the percentage of LKD, it led an the increase in the shrinkage limit by 500% in CH soil and 250% in CL soil. The free swell decreased by 50% in CH soil and 100% in CL soil. The swelling pressure decreased by 50% for two expansive soils. CBR increased by 800% in CH soil and by 150% in CL soil.Conclusion This work found that the addition of LKD improves the physical, chemical, and mechanical properties of expansive subgrade soil.