The　loess　strata　has　characteristics　such　as　collapsibility　and　structural　sensitivity.　Constructing　tunnels　in　this　formation　can　easily　lead　to　excessive　deformation　of　the　initial　supporting　structures,　especially　causing　cracking　and　heave　disasters　at　the　inverts　position,　which　affects　the　safety　during　both　the　construction　and　operation　periods.　This　article　firstly　analyzes　the　physical　properties　of　soft　plastic　loess　through　indoor　experiments.　Secondly,　specific　reinforcement　schemes　are　proposed　based　on　the　sleeve　valve　tube　grouting　reinforcement　mechanism.　Finally,　the　morphology,　moisture　content,　strength,　and　range　of　influence　of　loess　after　grouting　are　analyzed　through　on-site　monitoring　data　and　core　sampling　analysis.　The　results　indicate　that　the　plasticity　index　and　liquidity　index　of　the　loess　samples　are　12　and　0.55,　respectively,　with　an　average　liquidity　index　greater　than　0.50,　indicating　that　the　loess　samples　are　in　a　soft-plastic　state;　The　sleeve　valve　tube　grouting　reinforcement　technique　can　effectively　reduce　the　permeability　and　moisture　content　of　the　loess　formation,　as　well　as　improve　its　unconfined　compressive　strength;　The　influence　of　the　grouting　process　on　the　stress　in　the　surrounding　soil　gradually　decreases　from　near　to　far,　and　the　maximum　influence　radius　in　the　horizontal　direction　is　8.03　meters.　©　2024　The　Author(s).