The total length of the road design is 6820。460 meters, set as a highway, the speed of 60km / h, the average daily traffic forecast for the 12310, annual growth rate of 3。8%。

The plane design has five special points, three corners, three circular curve segments, the radius of 1034。7,291。878m and 1258。849m, the transition curve is 106。387m, 103。301m and 106。478m。 The minimum length of the straight line between the curves is less than 360 km for the straight line between the co-directional curves and the minimum length of the straight line between the reverse curves is not less than 120 km。 The design involves calculating the azimuth angle on the relaxation curve。

Vertical curve design using the "flat package vertical" principle, taking into account the three aspects of flat, vertical and horizontal test slope line, and then cross-sectional inspection check, determine the longitudinal slope, set the vertical curve radius, calculate the design elevation, Sectional view。 Set to 2 section vertical curve, the design as far as possible to use a larger radius, and pay attention to the distance between。

Cross-sectional design Arrangement of road lanes, central piders, sidewalks, shoulders and so on to determine their lateral geometrical dimensions, depending on traffic speed, combined with terrain, and other conditions。

The allocation of land and stone, through the deployment, a reasonable solution to the number of earth and stone road balance and utilization of the problem, in line with national policy and technical and economic principles, reduce the number of valuations, to avoid unnecessary borrowing and spoil。

The design of the subgrade is to consider the design of the subgrade and the stability of the soil by the arc method。 The arc method pides the soil on the sliding surface of the arc into several vertical soil sections, and calculates the soil along the sliding surface Down force and anti-skid force, and then superimposed to calculate the stability of the entire sliding soil。 Retaining wall is used to support the roadbed fill or hillside soil, to prevent the deformation of soil or soil deformation of a structure。

Pavement design includes asphalt pavement design and concrete pavement design。 (3 cm thick), the middle layer with medium-graded graded asphalt concrete (thickness 5cm), the use of three-layer asphalt concrete layer, the surface layer with fine graded graded asphalt concrete (thickness 4 cm) The lower layer of coarse graded graded asphalt concrete (thickness 6 cm)。 The thickness of ordinary concrete is 0。25m。 Base selection of lime-fly ash, thick 0。20m, E1 = 600Mpa。 The cushion is lime soil, 0。20m thick, E2 = 500Mpa。

Key words: flat curve design; cross section design

目 录

引 言 7

1 绪论 8

1。1 设计任务 8

1。2 任务要求 8

1。3 设计意义 8

1。4 交通量 8

2 线形确定 10

2。1 道路等级确定 10

2。1。1 公路等级的划分 10

2。1。2设计资料 10

2。1。3 规范及要求 10

2。2 选线 10

2。2。1 选线的意义 10

2。2。2 平原微丘地区公路路线特点 11

2。2。3 平原微丘地区选线要点 11

3 平面设计 11