Which of the following is transition curve?
Explanation: A clothoid is an ideal transition curve in which, length is inversely proportional to the radius of the curve. It is also known as Glover’s spiral. Explanation: Cubic parabola is also known as Froude’s transition curve.
Which is best for Valley curve?
For gradually introducing and increasing the centrifugal force acting downwards, the best shape that could be given for a valley curve is a transition curve. Cubic parabola is generally preferred in vertical valley curves.
What are the different types of valley curve?
Summit curve: When two grades meet at the summit and the curve will have convexity upwards, the curve is simply referred as summit curve. Valley (Sag) curve: When two grades meet at the valley (sag) and the curve will have convexity downwards, the curve is simply referred as the valley (sag) curve.
What are the elements of vertical curve?
Elements of Vertical Curve
- PC = point of curvature, also known as BVC (beginning of vertical curve)
- PT = point of tangency, also known as EVC (end of vertical curve)
- PI = point of intersection of the tangents, also called PVI (point of vertical intersection)
What is the minimum superelevation?
Minimum superelevation: If the value of superelevation obtained from the equations is equal or less than the usual camber value provided to the road surface then it should be equal to the camber slope. This lower limit of superelevation equal to the amount of camber is termed as minimum superelevation.
What is the most important structure in a Hill Road?
retaining wall
Which is the most preferred shape of drainage?
trapezoidal shape
What is the minimum design speed on the major district road of Hill?
30 Kmph
How do you build a road in hilly areas?
First it is necessary to construct the formation or the finished profile of hill road….Formation Works for construction of hill roads
- Trace-cut.
- Jungle clearance.
- Earth work excavation through soil and soft rocks.
- Rock cutting, drilling, blasting and clearing.
Which type of gradient is provided in hilly areas?
Types of gradient :
| Terrain | Ruling gradient | Experimental gradient |
|---|---|---|
| Mountainous terrain, and steep terrain having elevation more than 3,000 m above the mean sea level | 5 per cent (1 in 20) | 7 per cent (1 in 14.3) |
| Steep terrain upto 3,000 m height above mean sea level | 6 per cent (1 in 16.7 ) | 8 Percent ( 1 in 2.5 ) |
What are the part and function of hilly roads?
Retaining Walls ➤ Retaining walls are the most important structure in hill road construction. It provides adequate stability to the roadway & to the slope. ➤ Retaining walls are constructed on the valley side of the roadway. ➤ Retaining walls are constructed in stone masonry, brick masonry or cement concrete.
What are the general considerations are considering while aligning a hilly road?
Adequate drainage facility should be provided across the road. Attempts should be made to align the roads in such a way where the number of cross drainage structures required are minimum, which reduce the construction cost.
How many curves are commonly used in hill roads?
The types of curves provided on hill roads are as following: 1 Hair-pin curves, 2 salient curves, 3 Re-entrant curves.
What is the camber for high bitumen road?
For impervious pavement surfaces like cement concrete or bituminous concrete, a flat camber of 1.7% to 2% is to be provided. Whereas in pervious surfaces like Water Bound Macadam or earth roads steeper cross slopes should be provided.
What are the drainage and maintenance problem in hilly roads?
The downward and outward movement of slopes forming material is called landslide. Landslides and slips are the most important problems in the maintenance of hill roads. Traffic movement may be stopped due to landslides. So special care should be given to prevent landslides.