Study On The Disease Of Peat Soil Everglade Highway And Prevention In Yanbian Area

The topography, hydrology, geology and climate characteristics of peat land in Yanbian area, as well as cities and counties township living geographical characteristics which decide the limited distribution of the already and proposed highway, that is, along the banks of the River Line or running uphill lines, mostly at gully or beach. So it bad Hydrogeological area occupy a significant share, which result in uneven road subsidence, collapse, crack, frothing frost heave and other diseases and hidden dangers in weak peat soil roadbed.This study aims at diseases and potential hazards in adverse geological peat soil area in Yanbian region. To achieve high-quality projects virtuous circle, giving priority to science and technology, put entity project construction as support. introduce advanced practical technologies, develop the relevant research.Rely on the Ministry of the west building and technology projects "key technologies research on Yanbian peat land area of highway construction".The paper mainly does the following three studies:1) The main disease investigation for the peat soil marshes main highway in Yanbian region;2) Engineering properties study on peat soil in Yanbian region;3) Special study on plastic foam block (board) of highway construction in peat land, Yanbian area.The technical route is: based on the systematically survey on the main diseases of highway Route region. Mainly aimed at unique physical and chemical, mechanical properties in Yanbian region which is seasonally frozen peat soil marshes. Objective analyzed the causes and introduced appropriate countermeasures and treatment technology program. Through entities test project construction, measurement and tracking conclude, explored and research technical and economic feasible methods and effective way to mitigate common diseases in the region.Through the study reached the following conclusions : 1. By surveying the highway conditions in Yanbian peat soil area find that embankment, pavement, bridge and other structures have serious diseases, which not only affect the long-term endurable and safe operation, but it increase the workload of the maintenance of minor repairs, large and medium-sized repair, the cost significantly enhances. Therefore, the distinction with the general endemic prominent diseases, such as specific performance in the high embankment subsidence, vertical crack, the uneven subsidence of dwarf roadbed, the collapse lateral slip, rut weak and so on. Systematically analyze the causes of the disease. Summarize as these:1) The geologic conditions is extremely adverse, as well as the absence of the necessary countermeasures treatment in design and construction which is the main reason for higher embankment settlement cracking;2) The hydrological and geological conditions are adverse in peat land-based, and long-term vehicle dynamic load, adverse seasonal freeze-thaw cycle which lead to the capacity and the road structure strength reduce. These are the main reason of subgrade uneven subsidence, the collapse lateral slip, rut weak and so on;3) Large moisture, high porosity, high compression and heavy frost heaving, inappropriate treatment is the direct cause for subgrade disease.2. The peat soil physical properties indicators in Yanbian area change with the sampling depth, has great difference in depth layer. The chemical properties such as organic matter content, ignition loss has a marked difference in different depth layer. But the pH indicator is between 4.39-6.07; mechanical properties are different along the depth direction of compression, which shows the high compression, and a gradual transition to secondary compression. Comparatively speaking, the compression modulus is small; adopt direct shear and triaxial methods gain that the cohesion of the peat soil is within the 3-70KPa which is discrete, the internal friction angle is generally 5-30 degrees.The permeability of peat soil in the same load classification pressure has a direction, and change with the depth along the layer.3. Based on light embankment does a special study for the highway construction application of the plastic foam plate, block in peat land area. Summed up the construction process requirements, certificated its good insulation effectiveness and intensity stability. Discussed the practical significance of avoiding peat land, frost sink which roadbed occurred, raising embankment stability, ensuring the subgrade strength and pavement structure strength , and protecting the environment and peat soil wetland resources, improving the efficiency of construction, reducing frost and tympanites of roadbed.The conclusions of the studies and the law of peat land area of highway construction which has revealed has accumulated valuable experience. And provide a reliable technical support for poor subgrade evaluation of soft soil especially for seasonal frozen peat soil areas. The research results have a practical significance in reducing disease roadbed hidden dangers, improving resistance to deformation stability.Recommendations for future work: the location of plastic bubble, the reasonable reductions of subgrade height have yet to be determined in the future with the right conditions of the testing project.