Study On Settlement Control Technology Of Rock-soil Filled High Embankment In High Altitude And Cold Area

With the development of China's large-scale infrastructure construction,the traffic construction gradually shifted from the east to the west,from plains to mountains.Large and small high-filled embankments are inevitable in mountainous areas,and the settlement of high-filled embankment is one of the most important problems in the construction.The existing highway engineering shows that the high embankment in mountainous area is mostly filled with the stone or the earth and stone.the settlement of the embankment is mainly affected by the type of packing and the construction technology.In this paper,based on the road construction and practical engineering problems in Qinghai mountain area,combined with the related scientific and technological project of Research on Mechanized Construction and Quality Control Technology of Subgrade and High Embankment in Zhanian Highway.In view of the particularity of the high embankment in Qilian mountain area of Qinghai Province,We have studied the settlement control technology of high embankment in high-altitude and cold regions.It is aimed at determining the problems and finding the construction method of embankment settlement control in this environment to fill the blank of high-fill embankment construction in Qinghai mountainous area.The research methods and the embankment settlement control technical measures include:(1)Nearly three years of research and the verification of the project shows that there are problems such as the difficulties in the source of filling materials,Seasonal frozen earth,turbulent ice,and unstable geological disasters near the embankment.(2)The technical identified the slag in the tunnel of the project is slate,which belongs to medium hard rock and is a kind of well roadbed filler.(3)It is suggested that three types of paving thicknesses are filled with 70 cm,50cm,and 30 cm in the different locations of high-filled embankments.We have simulated the optimal combination of three loose-layer thicknesses before construction.Then,the overall structure of the fill is simulated by using the three padded layers after optimal compaction.and the layer thickness combination scheme with the smallest settlement of the entire filling is optimized.(4)The embankment should avoid low-temperature construction in winter;the optimal earth-rock ratio for embankment filling should be determined before construction;the foundation of the embankment is treated to bare rock;the embankment adopts a mixed paving method;The roller compaction is strictly implemented according to the best compaction process of simulation;the method of “fill first and build later” should be adopted when laying slope code.(5)we have established a set of embankment settlement observation program,which can make a detailed records of settlement changes during construction and postconstruction settlement of embankments,timely master the settlement of the entire embankment,and analyze the settlement variation of embankment through a large number of original data.On the other hand,it is also provided a useful engineering practice experience for similar projects and the construction of mountainous roads.