Bashir, RashidMoustafa, Moamenbellah Mohye Abdelhamid Elsayed2026-03-102026-03-102024-01-242026-03-10https://hdl.handle.net/10315/43543Hysteresis, a natural soil phenomenon, manifests distinct hydraulic responses influenced by the soil-water characteristic curve (SWCC), reflecting soil pore paths during infiltration and drainage. This study investigates the interplay between hysteresis and air entrapment, essential for accurate hydrological modeling under intermittent water flow. Despite their significance, numerical models often overlook hysteresis, relying on nonhysteretic curves. This research explores the impact of hysteresis with air entrapment on solute transport and slope stability in diverse scenarios. Comparisons between hysteretic and nonhysteretic analyses reveal increased water fluxes and deeper solute migration when considering both hysteresis and air entrapment. Neglecting these factors leads to inaccurate solute fate and slope stability assessments. In slope stability analysis, air entrapment significantly lowers suction strength and factor of safety, potentially triggering slope failures. This thesis establishes the critical importance of considering both hysteresis and air entrapment for robust hydrological and geotechnical assessments.Author owns copyright, except where explicitly noted. Please contact the author directly with licensing requests.Electronic Thesis or Dissertation2026-03-10HysteresisHydraulic hysteresisHysteretic SWCCHysteresis SWCCHysteresis SWRCHystereticHysteresis loopHysteresis envelopeAir entrapmentTrapped airEntrapment of airSolute transportContaminant transportSlope stabilityFactor of safetyStabilityUnsaturated shear strengthSuction strengthGeotechnicalGeo-environmentalGeoenvironmentalHydrogeologyHydrological modelHydrogeological modelNumerical modelingNumerical modelSaturated-unsaturatedUnsaturated soil mechanicsSubsurface drip irrigationTriggered irrigationEmbankmentSlopeSoil water characteristic curveSoil-water characteristic curveSoil retention curveInitial drying curveDrying curveWetting curveDrainage curveImbibition curveHysteresis modelClimateClimate interactionLand-climate interactionLand climate interactionAtmospheric boundary conditionNonhysteresisNon-hysteresisNonhystereticNon-hystereticHCFHydraulic conductivity functionPDEPartial differential equationLimit equilibriumHydraulic functionHydraulic characteristicsUnsaturated soilVariably saturated flowVariably saturatedSalt transportSDIDrip irrigationIrrigationSaltClimateClimate dataClimatic conditionHighway embankmentFOSWater flowVariably saturated water flowNet infiltrationRunoffActual evaporationEvaporationPotential evaporationInfiltrationClimate classificationBottom fluxContaminationGroundwater contaminationAquifer contaminationWater retention propertiesSolute displacementSolute movementSalt transportSalt accumulationCenter of massCOMDrip lineEmitterSolute distributionWater balanceSuctionWater contentConcentrationPressureSoil atmosphereSoil atmospheric boundary conditionSoil atmosphere boundarySlip surfaceSlope failureSlope instabilitySlope instabilitiesShear strengthCorrectionHysteresis effectHysteresis influenceEffect of hysteresisInfluence of hysteresisSlope stability modelSolute transport modelSWCCSWRCMatric suctionPressure headMoistureFinite element methodFEMUnsaturatedDryingWettingDrainageAnthropogenicAnthropogenic activityAnthropogenic activities