---
title: "Camber and its types"
subject: "Transportation Engineering I"
chapter: 3
key: "semester_6/transportation_engineering_i:camber-types"
source: https://www.bctengineer.com/q/semester_6/transportation_engineering_i/camber-types
site: BCT Engineering
---

# Camber and its types

Transportation Engineering I · Chapter 3: Geometric Design of Highway

- Asked in: 2078 Baisakh, 4 marks
- Video: [Camber - Highway Geometric Design - Transportation Engineering 1](https://www.youtube.com/watch?v=tmTWEB8OzCA) — Ekeeda
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_6/transportation_engineering_i/camber-types
- Whole chapter: https://www.bctengineer.com/md/semester_6/transportation_engineering_i/chapter-3

## Question

Discuss camber with its types.

## Short answer

Camber is the transverse slope on straight roads for drainage. Types include parabolic (best for high-speed bituminous/concrete), elliptical (higher speeds), straight-line (simple, low-cost), composite (parabolic center with straight edges), and one-way (single slope for curves/hill roads). Recommended values range from 1.7-2% for concrete to 3-4% for earth roads.

## Answer

**Camber (cross fall)** is the convexity or transverse slope given to the carriageway surface of a straight road, with the centre higher than the edges, to drain rainwater to the side drains.

#### Types of camber
1. **Parabolic camber:** the cross profile is a parabola, steeper near the edges and flat at the centre. The best for fast traffic; used for bituminous and concrete roads. Equation $y = \dfrac{2n\,x^2}{W}$ ($x$ measured from the centre line, $n$ = average cross slope, $W$ = width).
2. **Elliptical camber:** an elliptical profile; used for roads with higher speeds.
3. **Straight line (sloped) camber:** two straight slopes meeting at the crown; simple to construct; used for low-cost roads and with moderate speeds. A rounded crown is provided.
4. **Composite camber:** a parabola near the centre and straight lines near the edges; combination for better appearance and drainage.
5. **One-way camber (single slope):** the whole carriageway slopes to one side; used on curves (with superelevation), hill roads and one-way roads.

```text
 parabolic       straight         composite
   _.-"-._       __/\__           _.-"-._ 
```
#### Recommended values (IRC; check NRS 2070)
| Surface | Camber |
|---|---|
| Cement concrete, high bituminous | 1.7-2.0% |
| Thin bituminous | 2.0-2.5% |
| WBM / gravel | 2.5-3.0% |
| Earth road | 3.0-4.0% |

Higher camber is for heavier rain and rougher surface.

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. Parabolic camber is
   A. flat near the edges, steep at the centre
   B. steeper near the edges and flat at the centre; best for fast traffic
   C. two straight slopes only
   D. a one-way slope
   Answer: B. Parabolic profile is flat at the crown and steeper at the edges, suited to fast traffic. (Key point: Parabolic camber)

2. Straight-line camber is used mainly for
   A. high-speed concrete highways
   B. curves with superelevation
   C. low-cost roads with moderate speed
   D. urban kerbs
   Answer: C. Two straight slopes meeting at the crown are simple to construct for low-cost roads. (Key point: Straight camber)

3. Where is one-way camber used?
   A. On curves with superelevation, hill roads and one-way roads
   B. On wide divided highways only
   C. Only on earth roads
   D. Never on paved roads
   Answer: A. The whole carriageway slopes to one side in these cases. (Key point: One-way camber)

4. Which surface needs the greatest camber?
   A. Cement concrete
   B. Thin bituminous
   C. WBM
   D. Earth road
   Answer: D. Earth roads need 3-4%, rougher surfaces more than smooth ones. (Key point: Recommended values)