Module 2 Flashcards
(29 cards)
This data is beneficial for the utilized type of road (MDR, NH, SH) to be created on the path. This includes traffic volume survey, origin destination survey, vehicles damage surveys.
Traffic data
While constructing a highway, many shops and houses got affected or damaged, hence, this is done along road side, town villages, and shops.
Social survey
It is a report regarding affecting number of trees, flora, and fauna near construction sites, pollutants increased during construction in air and water must be prepared and submitted to environment ministry to get the green signal for development.
Environment Data
Under this survey condition of pavement and structures (bridges and culverts) along the road are taken. If the condition structures are poor, they need to be reconstructed. If conditions are fair, they are widened or repaired. If conditions are good, they are retained.
Roads Inventory and condition surveys
What is a important initial step in the design of a proposed highway?
determine the location
What can be the basis for selecting the location for highway?
- topography
- soil characteristics
- cost
- environmental factors
What are the four types of horizontal curve?
- Simple Curve
- Compound Curve
- Reverse Curve
- Spiral Curve
It is a circular curve used to connect two tangents intersecting at a point.
Simple Curves
It is the point where the curve leaves the first tangent, sometimes this point is called TC or tangent to curve.
Point of curvature (PC)
The point where the curve joints the second tangent, sometimes called CT or curve to tangent.
Point of Tangency (PT)
It is the point of intersection of the tangents.
Vertex
Other terms for vertex.
- PI
- Point of intersection
It is the distance from the vertex to the PC or PT.
Tangent Distance (T)
It is the distance from the vertex to the middle of the curve.
External distance (E)
It is the straight line joining the PC and PT.
Long chord (LC)
It is the line joining the middle of the chord with the middle of the curve.
Middle ordinate (m)
It is simply the radius of the curve.
Radius (R)
It is the deflection angle between the tangents.
Angle of intersection (I)
In highway practice where the radius are usually short and usually the distances are considered to be the same as along the arc, the degree of the curve is the angle at the center subtended by an arc of on full station.
Arc basis
It is where the curve is relatively of long radius, distances along the arc of the curve are connected to be the same as along the chord. This is the angle subtended by the chord of one full station.
Chord basis
How many full station is in one full chord?
1 full chord = 1 full station
How many meters are in one full chord?
1 full chord = 20 m
How many feet are in one full chord?
1 full chord = 100 ft
It is the chord less than one full station.
Sub-chord (C)
