Road construction course project

Contents

1. DEFINITION OF REQUIRED ROAD PARAMETERS

1.1. Establishing a Road Category

1.2. Setting of design road speed by SNiP 2.05.02-85 *

1.3. Defining Road Parameters

1.3.1. Establishing the number of lanes

1.3.2. Define the width of the carriageway, lane, and roadway

1.3.3. Defining the Smallest Radii of Curves in a Plan

1.3.4. Path Visibility

1.3.5. Determining the Smallest Radii of Vertical Curves

1.3.6. Defining Roadway Widening on Curves

1.3.7. Determining the Maximum Longitudinal Slope of a Road

2. DESIGN OF LONGITUDINAL PROFILE OF EARTH BED, DRAINAGE

2.1 Design of longitudinal profile

2.2. Ditch Design Requirements

2.3. Roadway construction

3. HYDRAULIC CALCULATION OF CULVERTS

3.1. Hydraulic Pipe Calculation

3.2. Small Bridge Hole Calculation

3.2.1. Determination of domestic depth

3.2.2. Establishing the flow pattern of water under the bridge

3.2.3. Determining the Size of the Bridge Hole

3.2.4. Refinement of calculation data

3.2.5. Determining the Height and Length of a Bridge

Literature

Source Data

1. The road is access to the facility.

2. The construction cost of the facility is 2900 million rubles, the construction period is 3.0 years.

3. Construction zone II (Leningrad region).

4. Design water flow Qcomp = 2.8 m3/s.

5. Hydraulic Pipe Calculation - Tip Type I.

6. Calculation of small bridge holes: Qrasch = 19.5 m3/s.

Design of the longitudinal profile of the roadbed, drainage

2.1 Design of longitudinal profile

Longitudinal profile contains ground surface line (black profile), terrain along road axis, soil and design line (red profile). In general, the longitudinal profile characterizes the geological conditions and the high-altitude position of the brow of the earth bed. The elevation of the eyebrow relative to the ground surface line, estimated by the working elevations, to a decisive extent determines the operational, strength and economic indicators of the road, as well as its durability. To obtain optimal results in the design of the longitudinal profile, the following shall be provided:

- necessary conditions for the movement of cars and the cost-effective operation of vehicles;

- smooth and safe movement of cars reaching the design speed;

- stability, reliability and durability of the road ;

-free functioning of the road;

-economics of road construction.

The necessary operating conditions are ensured by laying the design line with gentle longitudinal slopes.

SNiP 205.02-85 * recommends the use of slopes up to 30% about. If it is economically impractical to implement this recommendation due to terrain, it is allowed to apply longitudinal slopes that do not exceed the following maximum values: for category II road category - 40% o.

Smooth movement of cars is achieved by fitting circular vertical curves into the fractures of the design line, and safety - by assigning such radii of vertical curves that provide calculated visibility distances (on convex fractures) and limit centrifugal force within 5% of the weight of the car (on concave fractures). Vertical curves must be inscribed in fractures, where the algebraic difference of adjacent slopes Δi is equal to or greater than 5% on roads of category III. Lifts are considered positive slopes, descents are negative. The value Δi on fractures of associated slopes (two rises or descents) is defined as the difference in conjugated slopes, and on fractures of oncoming slopes (descent and rise, rise and descent) - as their sum .

The smallest values of the parameters of the longitudinal profile, which still ensure smoothness and safety of cars, are given in Table 10 of the SNiP. In projects, you should strive to use as large parameter values as possible - this improves the convenience and safety of traffic.

2.2. Ditch Design Requirements

On vertical curves, cuvettes repeat the real circular outline of the brow of the earth bed. Cuvettes are designed in the following sequence:

1. according to the values of the working marks, the places where the cuvette arrangement is necessary are established.

2. Specifies the slope of the bottom of the cuvette and the type of reinforcement .

3. a ditch bottom line is drawn in the drawing;

4. analytically determines the distance from the nearest station to points with zero working elevations and to the intersection points of the bottom of the ditch with a black profile (for this you need to consider the resulting geometric figure in the drawing: triangle or trapezoid, as well as make and solve the appropriate proportion);

5. specify design elevations of the ditch bottom at all its fractures, at pickets and at places of access to the surface ;

6. design slopes of cuvettes are recorded;

7. Specifies the distance between the fractures and snaps to the station of the ditch start and end points and points with zero elevations.

8. Calculations are checked (cuvette bottom elevations at the points of access to the surface must correspond to ground elevations; the difference between the design elevation of the edge of the roadway and the design elevation of the bottom of the ditch should be equal to the accepted depth of the ditch; in addition, the specified distances, slopes and elevations shall be in accordance with );

9. final drawing and corresponding graphs are made. Design data related to cuvettes is displayed in red.

Small Bridge Hole Calculation

Small bridge hole is calculated in the following sequence:

- determine the domestic depth of water flow in the non-sunken channel of the watercourse ;

- water flow scheme under the bridge is established;

- the size of the bridge hole is determined;

- the design data for typical dimensions of small bridges are specified.