# Highway Engineering PYQ – TN TRB Lecturer

1.â€ƒIn water bound roads binding material is _____ .

**[TN TRB 2012: 1 Mark]**

- Sand
- Stone dust
- Cement
- Brick dust

**Answer:**Option B

**Explanation:**

Binding material used in water bound roads must be fine grained to prevent the raveling of the stones. Kankar nodules or limestone dust can be used for this purpose.

2.â€ƒIf L is the length of a moving vehicle and R is the radius of curvature the extra mechanical widening to be provided on horizontal curves for single lane is _____ .

**[TN TRB 2012: 1 Mark]**

- L/2R
- L
^{2}/2R - L
^{3}/2R - 2L/R
^{2}

**Answer:**Option B

**Explanation:**

Extra Mechanical Widening, W

_{em}= nL

^{2}/ 2R

Where,

n – Number of lanes. For single lane, n = 1.

Thus, W

_{em}= nL

^{2}/ 2R

⇒W

_{em}= L

^{2}/ 2R

3. â€ƒAccording to IRC the maximum super elevation in rolling terrain in plains is limited to _____ .

**[TN TRB 2012: 1 Mark]**

- 4%
- 7%
- 10%
- 5%

**Answer:**Option B

**Explanation:**

As per IRC,

- The maximum super elevation that can be provided in plain and rolling terrain is 7%.
- The maximum super elevation that can be provided in hilly terrain is 10%.
- The maximum super elevation that can be provided in urban roads is 4%.

4. â€ƒIn which of the following traffic signal systems, cycle lengths and cycle division automatically varied?

**[TN TRB 2012: 1 Mark]**

- Simultaneous system
- Alternate system
- Simple progressive system
- Flexible progressive system

**Answer:**Option D

**Explanation:**

In a flexible progressive system, it is possible to automatically vary the length of cycle, cycle division and the time schedule at each signalized intersection using a computer.

5. â€ƒThe drain which is provided parallel to loading to intercept and divert the water from hill slopes is called _____ .

**[TN TRB 2012: 1 Mark]**

- Slope drain
- Catch water drain
- Side drain
- cross-drain

**Answer:**Option B

**Explanation:**

Catch water drain runs parallel to the roadway and diverts water from hill slopes.

6. â€ƒIf Î¸ is the angle of slope, L is the length of slope and h is the difference in elevation between two ends of the line, then slope correction will be _____ .

**[TN TRB 2012: 1 Mark]**

- L sin θ
- 2L sin
^{2}(θ/2) - L sin (θ/2)
- 2L sin 2θ

**Answer:**Option B

**Explanation:**

Slope correction, C

_{s}= – L (1 – Cos θ)

⇒ C

_{s}= – L 2Sin

^{2}(θ/2)

⇒ C

_{s}= – 2L Sin

^{2}(Î¸/2)

Since, the slope distance will always be more than the horizontal distance, the slope correction is always negative.

7. â€ƒIsogonic lines are lines passing through _____ .

**[TN TRB 2012: 1 Mark]**

- Points having same declination
- Points of zero declination
- Points having same dip
- Points having zero dip

**Answer:**Option A

**Explanation:**

- The lines connecting the points having the same magnetic dip are isoclinic lines.
- The lines connecting the points having zero magnetic dip are aclinic lines.
- The lines connecting the points having the same magnetic declination are isogonic lines.
- The lines connecting the points having zero magnetic declination are agonic lines.

8. â€ƒSpire test is used for adjustment of _____ .

**[TN TRB 2012: 1 Mark]**

- Line of sight
- Horizontal axis
- Vertical axis
- Adjustments of altitude bubble

**Answer:**Option B

**Explanation:**

Spire test is used to ensure that the horizontal axis is truly horizontal.

9. â€ƒSize of a theodolite is specified by _____ .

**[TN TRB 2012: 1 Mark]**

- Diameter of lower plate
- Diameter of upper plate
- Length of telescope
- Diameter of vertical circle

**Answer:**Option A

**Explanation:**

The diameter of the lower plate is used to specify the size of theodolite. An 8 cm theodolite represents that the graduated circle of the lower plate is of 8 cm diameter.

10. â€ƒIf Î” is the angle of deflection of a simple curve of radius R, the length of the curve is _____ .

**[TN TRB 2012: 1 Mark]**

- Ï€RÎ”/90
- Ï€RÎ”/180
- Ï€RÎ”/270
- Ï€RÎ”/360

**Answer:**Option B

**Explanation:**

Length of the curve, l =

x Δ