Highway Roadbed Defects Reinforcement Technology Applied Research, And

The engineering of fencing and reinforcement of subgrades is an important measure for subgrade problems which can promises the steady of subgrades and can improves the view and the balance of the environment. In recent years, the building of freeways comes into a state of vigorous development. However, the national technical level and experience of constructing freeways are limited. Freeways, which have already been open to traffic or under construction, have problems more or less. These problems have direct influence on the quality and normal management of the freeways. At the moment, the remedial method of the problems of roadbeds, road surface, channels and so on are not so many. Most of the measures adopt the maintaining experiences, equipments and methods for the common highways, which can not satisfy the need of higher freeways. Therefore, the application research and improvement of the new technology of remedy for the bugs is an important task at present.From the analysis of the types and causes of usual problems of the subgrades, the thesis mainly researches on the application of following technologies: technology of treatment for the sinkage of high filled embankments, technology of strengthening of special subgrades (karsts collapse and mollisol roadbeds), and technology of remedy for problems of slopes of the bed.The reinforcement of high filled embankments adopts the method of chemical grouting which successfully dealt with part of the sinking subgrade of the north to south freeway in Guangxi Province from K0+000~K64 + 900. The thesis expounds the application of chemical grouting in the sinking subgrades from basic theories, design scheme, the principle of construction and other aspects. The reinforcement of high filled embankments also adopts the mortar grouting method of granulose slurry which successfully dealt with the sinking roadbed of No.130 freeway from Zhonggong to Liupu 19k+500(backfilled part at the back of the road) and 29k+300(south of the Liupu Bridge) in our Province. The thesis explains the promotion and application of the utility of mortar grouting method in the roadbed which has problems for the lax consolidation, mollisol and improper stuffing, etc. Through these examples, it can be concluded that mortar grouting method avoids the great economic waste , the poor quality and the bad effect of the society which brings by the traditional method of remedy of subgrades which needs excavating after the halt of traffic and replacing the stuffing. Thereby, the promotion of the mortar grouting method can bring significant social and economic profits.