Practice And Exploration Of New Measures Of Governing Subgrade Disease In Permafrost Region

Because of its special natural and geographical environment, the frozen earth suffered alot of unfavorable effect in permafrost region and there emerge more diseases of differenttypes and larger scale compared with it did in hinterland of China. The existing maintenancemeasures contains less power to prevent the main diseases such as longitudinal crack, thawsettlement and consolidation, the looseness of side slope in permafrost regions. There oftenemerge diseases of different types soon after repairing; sometimes because of its unreasonablemeasures there even emerge new type of disease. To slow down the development of diseaseand reduce its scale, it is urgent to seek some new measures or improve the exiting methods.This paper proposed four methods against the main roadbed problems by the way ofimproving, introduce and innovation. By testing in a real project, these new methods can beverified to prove their feasibility. This paper will introduce the procedure by placingwater-repellent geotextile under dry-laid masonry and side drain to avoid the vulnerablecharacter of cement mortar, at the same time, another advantage of this measure is it canreduce heat emission and drain the standing water. Changed the measure of only usinggrouting or using flexible corbel and add geotextile bag to improve the disadvantage of thelack of power to stop the expansion of the longitudinal crack with the tenons of the geotextilebag. Cement Gravel Mixing Trenchless is used to increase the bearing capacity of subgrade,to avoid the hydration heat which makes the permafrost thaws; cement is abolished in theoriginal underground part bottom of CGMT, only breakstone left. To avoid thaw settlementand consolidation emerge once again and to avoid CGMT becoming a channel of water,geotextile and Dry assemble stone tablets are combined to solve the problem. Differentschemes of firming agent are carried out to fining out an effective and convenient method tosolve the problem of looseness of side slope.