The total length of the road is 6871.693 m , set to the second - grade highway , the speed is 80km / h , the annual average daily traffic volume is forecast to be 7890 , the annual growth rate is 5.3 % .

There are 6 special points in the plane design, 4 corners and 4 sections of circular curve, with a radius of 1 900 m,1 500 m,600 m,1 000 m. The transition curves are 130 m,250m, 250 m,250)m . The minimum length of straight line between syntropy curves should be not less than 480 km and the minimum length of straight line between reverse curves should not be less than 160 km.

In the stage of vertical curve design, the "horizontal package vertical" principle is adopted. In all aspects, the slope line is determined in three aspects, flat, longitudinal and horizontal. The vertical slope value is determined, the vertical curve radius is determined, the design elevation is then calculated, and the longitudinal section map is completed.

In the phase of cross section design, according to traffic volume, driving speed and terrain, the layout of road lane and road shoulder is determined, and the transverse geometric size is determined. On the basis of standard cross section, the cross section of each pile is designed to improve driving comfort and safety.

Earthwork deploymen is pided into horizontal and vertical allocation. And calculate the debit, discards and the total volume. The balance and utilization of the quantity of earth and stone in the design road can be solved by the allocation of earth and rock. Under the condition of national policy and technical economy, excavating and filling should be carried out as far as possible to avoid unnecessary debit and abandoned soil.

Roadbed design focuses on subgrade design and the use of circular arc method to calculate soil stability. The retaining wall is built to prevent the soil from collapsing and is mainly subjected to lateral earth pressure. Used for embankment support, cutting slopes, tunnel openings, bridge ends and so on. Design of retaining wall and layout of drainage facilities. Gravity retaining wall is used in retaining wall. Gravity retaining wall is simple in structure and easy in construction, so gravity retaining wall is adopted.

Keywords : road design ; subgrade pavement design

目 录

设计总说明 2

引 言 7

1 绪论 7

1.1 设计任务 7

1.2 任务要求 7

1.3 设计意义 7

1.4 交通量 8

1.5 公路技术标准 8

2 线形确定 9

2.1 道路等级确定 9

2.1.1 公路等级的划分 9

2.1.2 已经设计资料 9

2.1.3 查规范 9

2.1.4 确定公路等级 9

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 10

2.2.3 平原微丘地区选线要点 10

3 平面设计 10

3.1 平面设计的要求 10

3.2 参数确定，查《公路工程技术标准》 11

3.2.1 公路服务水平 11

3.2.2 圆曲线最小半径 11

3.2.3 缓和曲线最小长度 11

3.3平面线形设计 11

3.3.1 方位角、转角计算 11

3.3.2 平曲线要素,各特征点桩号计算 13

3.3.3 定桩 18

3.3.4 坐标计算 18

3.4设计成果 21

3.4.1直线、曲线及转角表 21

3.4.2 逐桩坐标表 21

3.4.3 路线平面图 21

4 纵断面设计 22

4.1 概述 22

4.2 纵坡与坡长设计 22

4.2.1 纵坡设计的有关规范和要求 22

4.2.2 坡长设计的有关规范和要求 22

4.3 竖曲线设计 22

4.3.1 纵断面设计的方法与步骤 22

4.3.2 竖曲线 23

4.3.3 竖曲线计算 23

4.3.4设计成果 27

5 横断面设计 28

5.1 概述 28

5.2 横断面组成及要素确定 28

5.2.1 横断面组成 28

5.2.2 横断面要素确定 28

5.3 横断面设计步骤 29

5.4 加宽设计 29

5.5 超高设计 29

5.5.1 超高横坡度的确定 29

5.5.2 超高设置的判定 29

5.5.3 超高缓和段长度的确定 29