| With the rapid development of the economy, the traffic volumes of highway are rapidly increasing. The capacity of the old highways cannot meet the current traffic development, thus reconstruction or extension of highways is an important issue. The widening of old highways is a main form of renovation and expansion project.The differential settlement of the old and new embankment will pass to the road pavement structure to generate disaster when the differential reaches a level. It will be seriously affect traffic safety. In this paper, aimed at the differential settlement of the old and new embankment, unifies the 110 State Road widening project of Hohhot-Jining typical sections,the factors of the differential settlement of the old and new embankment are analysis. The main work and conclusions can be given as follows.(1)By selecting some representative sections, the changing law of engineering properties of ground under old and new embankments is explored by geological survey and soil mechanics assay.(2)Finite element model is built to analyze the characteristics and the changes of the differential settlement of the old and new embankment in different conditions.(3)The treatment measures of the joint and the effect of improvement are studied between the old and new embankment. According to the finite element analysis, the recommendations of height 80-100cm, width 100～150cm excavation reclamation methods had been determined. The lower embankment may use geogrid on the bottom of embankment; when the higher, increase the number of the geogrid from down to up. Meanwhile, use geogrid on the embankment priority can reduce the structure of pavement for the differential settlement of the old and new embankment. |
