Study On Classification And Design In Levee Road

It is an embankment and road combination engineering.Levee road takes both flood control and transportation double actions.Levee road is developing rapidly in China,but due to obscure function planning,it exits many problems such as unclear design index basis,unreasonable traffic management measures,unsuitable transect disposal.On the basis of past research,kinds of technology methods have been adopted to the dissertation,such as literature and field research,theoretical analysis and verification of existent projects.From the guarantee of flood control as the basic function,for the purpose of expanding road function,this dissertation constructs the classification system and explanation,study road width design method,calculates subgrade humidity evolution of levee road,summarizes main points of subgrade design.The paper sums up three types of embankment road combination.Through summarizes design flaws,the design idea and method of levee road are put forward.By analyzing the function of the existing levee road,including flood fights,dike management,transport,social services and supporting facilities,it proposes function classification method through combination of function,grade and area.According to the degree of role played in 5 functions,levee road is divided into 4 categories: flood control road,comprehensive road,traffic road and landscape road.At the same time,levee road construction standards divides into 2~3 levels in accordance with level of the dike and traffic volume.On the basis of functional classification,the design features and 4 factors affecting road width of levee road such as flood control,traffic function,land use and landscape greening are put forward.The dissertation concludes forms and characters of levee road cross section,gives detail calculation and analysis to widths and arrangement of motor vehicle lane,non motorized vehicle lane,curb side strip and separator.Then the design indexes of road width are given and 15 kinds of recommended roadway for different types of levee road are presents.Subgrade humidity of levee road changes is complicated because it is washed and eroded long term and erosion position changes with the water level.Sources of humidity mainly include atmospheric precipitation,surface water,groundwater and condensed water.The main factors that could influence humidity are: water level,levee type,slope protection,groundwater level,levee materials,subgrade compaction and pavement.Based on unsaturated soil theory,using SEEP/W software establishs model,the paper analyzes the evolution of subgrade humidity field under the influence of different river level,levee permeability and rainfall duration after covering the pavement.The simulation results show that surface water and groundwater have a significant effect on the humidity of road bed;subgrade humidity is greatly affected by permeability of levee body soil;rainfall has a significant effect on the humidity of upper subgrade and significant regional position depending on the duration of rainfall and water level of the water side;pavement coverage can effectively reduce the influence of rainfall on the subgrade humidity.From the numerical calculation,it is found that the subgrade is affected by surface water and groundwater,so it belongs to the wet subgrade.According to the characteristics of embankment and road,the paper summarizes the main points of slope and protection,subgrade widening,seepage prevention,subgrade compaction and subgrade drainage design.The paper investigates objective environment and design parameters,the combination form and function analysis of levee road,the design of road width and subgrade of the typical section on Weihe.The analyses show that the findings are consistent with the main conclusions of this paper.Problems found in some paragraphs can be improved and optimized by the results of this study.Then the conclusions are verified by the incestigation.