Northern Zhejiang Expressway Low Embankment Design Key Technology Research

In the soft clay area, traffic load will take effect on the deformation and tress of the roadbed a lot when adopting low embankment design method in the expressway. Now the study in this field had been done a little at home and abroad. Base on this background, this paper aim at the critical technology of low embankment design in the north of ZheJiang province. much work of investigation was fulfilled, dynamical response of low embankment expressway under the traffic loads with finite element method was study, and In order to research the method of the soft groud disposal on the low embankment,locale experimentation was launched.At last,according to the production of aforsaid,effective method of design were explored. The mean business was as follows:(1)Through one month's investigation on five expressways in the north of zhejiang province, the data of the design including pavement,padding,drainage of pavement and bed,disopal of soft groud , and the displacement of the soft groud were obtained. And realize the actuality and the influencing factor of the embankment height, as also the open question.(2)Analyzing dynamical property of the traffic loads,movable invariable load are decided on as the simulation of traffic loads; According to the property of linear-elastic model of the geotecnichal material,danamic equation was built and soluted.(3)Transformation rule about dynamical displacement and stress under different depth of low embankment expressway on the action of traffic load was gained by studying foundation response under all kinds of situation such as different height, different load, and different rigidity of pavement and base of pavement.(4)The lime soil method was applied to improve the soft groud,the experimental result prove that that the strength of the soil was improved a lot( the modulus of the soil resilence improve 6～7 times )by adding 6% lime to soil,and the water resistance was also improved; according to the field conduct, the craft and guideposts were also established. (5)Preparatory approarch was made on the designing method of debasing the height of embankment;the philosophy ,cycle and specific method of designing were also put forwards.