Research On XPS Insulation Board Treatment Technology In Insular Permafrost Subgrade

With global warming and road engineering development, artificial frozen soil under theceiling move, leading to the melt of permafrost under subgrade settling diseases, so frozensoil thermal stability is the key to the subgrade stability.In hulunbeier, Inner Mongolia islandof frozen soil in permafrost south of Eurasia, belonging to the high latitudes of permafrostwhich is sensitive to temperature. At present in permafrost subgrade treatment technology toprotect permafrost measures are mainly (1) active cooling protection permafrost methods,such as hot rod, gravel roadbed etc.,(2) the passive protection frozen soil methods, such asinsulation board, sun visor roadbed etc.Considering technical and economic factors, insulationboard roadbed has better prospects, but for insulation board roadbed structure parameterssuch as burial depth and the thickness of the insulation board and insulation board with thekey technology of insulation board roadbed construction has yet to be studied and discussed.In this paper the hulunbuir city bork chart-yakeshi expressway (hereinafter referred toas the Boketu-Yakeshi expressway) based on the project, mainly to carry out a study of thefollowing aspects: the XPS insulation board in permafrost region application effect and KeyConstruction Technology, construction season, jointing type of board, reasonable compactionthickness of subgrade fillers board subgrade and Engineering performance requirements ofXPS board are obtained; According to the actual climate conditions along Boketu-Yakeshiexpressway, the temperature field models for subgrade temperature field taking into phasetransition account are established. The influence law is studied by factors such as subgradeheight, grade of side slope, subgrade structure, pavement structure, and water content;According to stress analysis of pavement with different levels of subgrade settlement underweight and vehicle loads, taking compressive strength and allowable compressive stress ofXPS board as indicators, taking into account the results stress dispersion principle results andthe influence of rollers, the reasonable placing depth of XPS board is recommended.According to tensile properties of pavement structure material, material fatigue properties,slope and ride comfort, control standards of subgrade settlement are proposed; Replacementgravel XPS board subgrade structure and vertical grogrid dealing with permafrost transitionroad section test road are paved; Through temperature, moisture content and settlementobservations, the treatment effect for subgrade settlement of various schemes is verified.