National Institute of Technology Srinagar

The efficient utilization of construction waste in road engineering is essential for advancing sustainable infrastructure development. This study explores the application of ceramic waste powder (CWP) in cementitious grout for semiflexible pavement (SFP) surfaces. Cement was partially replaced with CWP at proportions ranging from 15% to 50%, and its effects on SFP performance and environmental impact were evaluated using compressive strength testing, life cycle assessment (LCA), and statistical analysis. The obtained SFP mixtures were assessed for volumetric and mechanical properties through Marshall stability and wheel tracking tests. Experimental findings revealed that 20% cement replacement with CWP was the optimal level, leading to an 80% reduction in rutting depth and increases of 50% and 23% in compressive strength and Marshall stability, respectively, at 28 days of curing. These improvements are attributed to CWP’s superior fluidity in filling the voids within the porous asphalt skeleton and its effective bonding capacity with aggregates, which densifies the microstructure, as confirmed by scanning electron microscopy (SEM) analysis. LCA results indicated that higher CWP replacement levels reduced both global warming potential and fossil fuel depletion, thereby enhancing the grout’s sustainability. Statistical analyses, including quadratic regression, ANOVA (p<0.05), and the Tukey HSD test, confirmed significant improvements in strength properties with CWP incorporation, whereas box plots effectively illustrated data trends and variations. In summary, this study underscores the dual environmental and performance benefits of incorporating CWP in SFP systems and supports its adoption in sustainable road construction aligned with circular economy goals.

Landslides are among the most destructive natural hazards in the Himalayan region, where steep terrain, complex lithology, heterogeneous soil cover, and intense hydro-meteorological forcing collectively govern slope instability. Despite growing recognition of ARs as major contributors to extreme rainfall, their explicit integration into physically informed slope stability assessments in the Himalayas remains limited. This research aims to investigate the impact of atmospheric-river-driven precipitation on slope stability across the Himalayan region by coupling landslide inventory data, soil characteristics, topographic controls, and slope stability theory. landslide occurrences are analyzed with respect to topographic parameters derived from digital elevation models, such as slope angle, elevation, and terrain morphology. Given the limited availability of site-specific geotechnical data over large mountainous regions, soil mechanical properties specifically cohesion and angle of internal friction are inferred from soil type and texture classes obtained from global soil databases. Representative ranges of shear strength parameters are assigned based on established values reported in the literature.Temporal characteristics of AR events, including shape, movement, intensity, duration, and antecedent moisture conditions, are linked with observed landslide occurrences to identify critical thresholds associated with slope failure. Slope stability is evaluated using the factor of safety (FOS) concept derived from limit equilibrium principles for infinite and shallow slope conditions. The influence of atmospheric rivers is incorporated through rainfall-induced changes in pore-water pressure and effective stress, enabling assessment of strength reduction and progressive destabilization under extreme precipitation scenarios. The outcomes of this research are expected to quantify the degradation of slope stability associated with atmospheric-river-driven rainfall, identify soil and terrain combinations most susceptible to AR-induced failures, and provide a physically meaningful explanation for observed landslide spatial clustering during extreme precipitation events. By integrating atmospheric processes with geotechnical slope stability analysis, this study advances the understanding of hydro-geomorphic hazards in the Himalayas and contributes to improved landslide susceptibility assessment, risk mitigation, and climate-resilient land-use planning in mountainous regions.

Abstract With growing demands for high-performance materials in marine, aerospace, and automotive applications, there is an urgent need to explore advanced solutions that combine sustainability with superior mechanical and functional properties. Conventional manufacturing techniques often fall short in meeting these requirements while maintaining environmental compatibility. Addressing this challenge, friction stir processing (FSP)—a green, solid-state technique—has been employed to fabricate Al2O3-reinforced aluminum 5052 (AA5052) surface composites (SCs) with exceptional multifunctional enhancements. Microstructural characterization revealed that the uniform dispersion of nano-Al2O3 particles (with an average particle size of ∼50 nm) by FSP induced a remarkable ∼90% reduction in grain size, from ∼100 µm in the base material (BM) to ∼2–4 µm in the stir zone, due to dynamic recrystallization and severe plastic deformation. Tribological assessments under dry sliding conditions demonstrated a 40% reduction in wear-rate and a 20% lower coefficient of friction, attributed to the protective tribolayer formed by Al2O3 debris. Corrosion performance in 3.5% NaCl solution showed a 29% decrease in corrosion rate, with the composite exhibiting a nobler corrosion potential (−0.709 V versus −0.964 V for BM) and higher charge-transfer resistance. These findings highlight the potential of FSP-developed Al2O3/AA5052 SCs as sustainable, high-performance materials for demanding environments.