1  

AS-4084 GURU GHASIDAS VISHWAVIDYALAYA, BILASPUR (C.G.)

INSTITUTE OF TECHNOLOGY DEPARTMENT OF CIVIL ENGINEERING

B.TECH 2nd YEAR, IVth SEMESTER SUBJECT: TRANSPORTATION ENGINEERING-I

SECTION-A

Solution 1: 1. (a) 5 2. (a) Surface drainage 3. (b) 0.15 4. (c) 4 5. (a) Traffic intersection 6. (a) Cycle length 7. (b) Flash point 8. (d) 2055 9. (b) Flaps 10. (c) Sucking effect

SECTION-B

Solution 2:

2  

 3 

4  

5  

Solution 3a:

FACTORS AFFECTING ROAD ALIGNMENT

a. Design speed

b. Topography

c. Other factors

i. Vehicle

ii. Human

iii. Traffic

iv. Environmental

v. Economy

vi. Others

Design speed

1. Design speed is the single most important factor that affects the geometric design.

2. Affects the sight distance, horizontal curve and the length of vertical curves.

3. Speed of vehicles vary with driver, terrain etc, a design speed is adopted for all the geometric design.

4. Design speed is defined as the highest continuous speed at which individual vehicles can travel with safety on the highway when weather conditions are conducive.

5. At the same time, a higher design speed has cascading effect in other geometric designs and thereby cost escalation. Therefore, an 85th percentile design speed is normally adopted. This speed is defined as that speed which is greater than the speed of 85% of drivers. In some countries this is as high as 95 to 98 percentile speed.

Topography

1. Next important factor that affects the geometric design is the topography.

2. It is easier to construct roads with required standards for a plain terrain.

3. However, for a given design speed, the construction cost increases multiform with the gradient and the terrain. Therefore, geometric design standards are different for different terrain to keep the cost of construction and time of construction under control. This is characterized by sharper curves and steeper gradients.

Other factors

In addition to design speed and topography, there are various other factors that affect

the geometric design and they are briefly discussed below:

6  

1. Vehicle: The dimensions, weight of the axle and operating characteristics of a vehicle influence the design aspects such as width of the pavement, radii of the curve, clearances, parking geometrics etc. A design vehicle which has standard weight, dimensions and operating characteristics are used to establish highway design controls to accommodate vehicles of a designated type.

2. Human: The important human factors that influence geometric design are the physical, mental and psychological characteristics of the driver and pedestrians like the reaction time.

3. Traffic: It will be uneconomical to design the road for peak traffic flow. Therefore a reasonable value of traffic volume is selected as the design hourly volume which is determined from the various traffic data collected. The geometric design is thus based on this design volume, capacity etc.

4. Environmental: Factors like air pollution, noise pollution etc. should be given due consideration in the geometric design of roads.

5. Economy: The design adopted should be economical as far as possible. It should match with the funds alloted for capital cost and maintenance cost.

6. Others: Geometric design should be such that the aesthetics of the region is not affected.

7  

Solution 3b:

Importance of Road Drainage

8  

Solution 4:

i. Kerbs Kerbs indicate the boundary between the carriage way and the shoulder or islands or footpaths. Different types of kerbs are (Figure 1): a. Low or mountable kerbs b. Semi-barrier type kerbs c. Barrier type kerbs d. Submerged kerbs

a. Low or mountable kerbs • This type of kerbs are provided such that they encourage the traffic to remain in

the through traffic lanes and also allow the driver to enter the shoulder area with little difficulty.

• The height of this kerb is about 10 cm above the pavement edge with a slope which allows the vehicle to climb easily.

• This is usually provided at medians and channelization schemes and also helps in longitudinal drainage.

b. Semi-barrier type kerbs

• When the pedestrian traffic is high, these kerbs are provided.

• Their height is 15 cm above the pavement edge.

• This type of kerb prevents encroachment of parking vehicles, but at acute emergency it is possible to drive over this kerb with some difficulty.

c. Barrier type kerbs

• They are designed to discourage vehicles from leaving the pavement.

• They are provided when there is considerable amount of pedestrian traffic.

• They are placed at a height of 20 cm above the pavement edge with a steep batter.

9  

d. Submerged kerbs

• They are used in rural roads.

• The kerbs are provided at pavement edges between the pavement edge and shoulders.

• They provide lateral confinement and stability to the pavement.

ii. Shoulders

Shoulders are provided along the road edge and are intended for accommodation of stopped vehicles, serve as an emergency lane for vehicles and provide lateral support for base and surface courses.

The shoulder should be strong enough to bear the weight of a fully loaded truck even in wet conditions.

The shoulder width should be adequate for giving working space around a stopped vehicle.

It is desirable to have a width of 4.6 m for the shoulders.

A minimum width of 2.5 m is recommended for 2-lane rural highways in India.

iii. Formation width

10  

Solution 5:

Easement or Transition Curves

Easement or Transition curve is provided to change the horizontal alignment from straight to circular curve gradually and has a radius which decreases from infinity at the straight end (tangent point) to the desired radius of the circular curve at the other end (curve point).

There are five objectives for providing transition curve and are given below:

1. To introduce gradually the centrifugal force between the tangent point and the beginning of the circular curve, avoiding sudden jerk on the vehicle. This increases the comfort of passengers.

2. To enable the driver turn the steering gradually for his own comfort and security,

3. To provide gradual introduction of super elevation.

4. To provide gradual introduction of extra widening.

5. To enhance the aesthetic appearance of the road.

Type of easement curve

Spiral or clothoid

Cubic parabola

Lamniscate.

IRC recommends spiral as the transition curve because it fulfills the requirement of an ideal transition curve, that is

Rate of change or centrifugal acceleration is consistent (smooth).

Radius of the transition curve is ȸ at the straight edge and changes R to

at the curve point ( ) and calculation and field implementation is

very easy.

Length of transition curve

The length of the transition curve should be determined as the maximum of the following three criteria:

Rate of change of centrifugal acceleration

Rate of change of super elevation

An empirical formula given by IRC.

Rate of change of centrifugal acceleration, at the tangent point, radius is infinity and hence centrifugal acceleration is zero.

At the end of the transition, the radius R has minimum value R.

11  

The rate of change of centrifugal acceleration should be adopted such that the design should not cause discomfort to the drivers.

If c is the rate of change of centrifugal acceleration, it can be written as:

a. Rate of change of centrifugal acceleration, at the tangent point, radius is infinity and hence centrifugal acceleration is zero.

At the end of the transition, the radius R has minimum value R.

The rate of change of centrifugal acceleration should be adopted such that the design should not cause discomfort to the drivers.

If c is the rate of change of centrifugal acceleration, it can be written as:

• Therefore, the length of the transition curve Ls1 in m is

where c is the rate of change of centrifugal acceleration given by an empirical formula suggested by by IRC as below:

b. Rate of introduction of super-elevation

• Raise (E) of the outer edge with respect to inner edge is given by .

• The rate of change of this raise from 0 to E is achieved gradually with a gradient of 1 in N over the length of the transition curve (typical range of N is 60-150).

Therefore, the length of the transition curve Ls2 is:

12  

c. By empirical formula

IRC suggest the length of the transition curve is minimum for a plain and rolling terrain:

For steep and hilly terrain is:

and the shift s as

The length of the transition curve is the maximum of equations for , i.e.

 

SSolution 6:

13 

 

14 

 

15 

 

SSolution 7:

16 

 

 

17 

18  

Solution8:

AIM   To determine the water absorption of the given coarse aggregate. 

 

EQUIPMENT  i. Container:  

              a. one cylinder measure, 3 litres capacity. 

              b. one cylinder measure, 15 litres capacity. 

              c. one cylinder measure, 30 litres capacity    

ii. One tamping rod. 

iii. Balance. 

iv. Electric Oven 

 

 

FIGURE: 

    

   

1)Cylinder metal measure 2) Cylinder metal measure 3)Cylinder metal measure 4) Tamping Capacity 30 litres Capacity 15 litres Capacity 3 litres rod

 

THEORY  Water absorption ratio = weight of wet sample – weight of dry sample

                                                           Weight of dry sample 

 

19  

PROCEDURE  1. The coarse aggregate passing through IS 10mm sieve is taken about 200g. 

2. They are dried in an oven at a temperature of 110o ±5oC for 24 hours. 3. The coarse aggregate is cooled to room temperature. 4. Its weight is taken as (W1g) 5. The dried coarse aggregate is immersed in clean water at a temperature 

27o ±2oC for 24 hours. 6. The coarse aggregate is removed from water and wiped out of traces of 

water with a cloth. 7. Within three minutes from the removal of water, the weight of coarse 

aggregate W2 is found out. 8. The above procedure is repeated for various samples. 

 

OBSERVATION TABLE:‐ 

Sample No.  Weight  of  oven  dried specimen (W1) gm 

Weight  of saturated specimen (W2) gm 

Weight  of  water absorbed            W3 = (W2 – W1) 

%  of  water absorption            = (W3/W1) * 100 

     

     

 

CALCULATION  Weight of dry sample of coarse aggregate W1 = 

Weight of saturated specimen W2 =  

Weight of water absorbed W3 = W2 – W1 =  

RESULT  Water absorption of the coarse aggregate is ____________. 

 

LIMIT  The water absorption of aggregates ranges from 0.1 to 2.0 % 

 

 

 

20  

                                                                                                                                                                                                               

AIM   To determine the specific gravity of the given coarse aggregate. 

EQUIPMENT  i. A wire basket of not more  than 6.3 mm mesh or a perforated container of convenient size with thin wire hangers for suspending it from the balance. 

ii. A thermostatically controlled oven to maintain temperature of 100o to 110o C. 

iii. A container for filling water and suspending the basket. iv. An airtight container of capacity similar to that of the basket. v. A weighing balance. vi. A shallow tray. vii. Dry absorbent clothes 

 

FIGURE: 

 

 

 

21  

THEORY  Specific gravity of aggregate is the ratio of density of aggregate to the density of water at 4⁰C.

                            Specific gravity = Density of aggregate  

                                                          Density of water at 4oC 

PROCEDURE  1. Take about 2 kg of the aggregate sample.

2. Aggregate sample is washed thoroughly to removes fines and drained. 3. Aggregate then placed in the wire basket and immersed in distilled water

at a temperature between 22o to 32o C with a cover of atleast 50 mm of water above the top of the basket.

4. Immediately after immersion the entrapped air is removed from the sample by lifting the basket containing it 25 mm above the base of the tank and allowing it to drop 25 times at the rate of about one drop per second.

5. The basket and the aggregate should remain completely immersed in water for a period of 24+ 0.5 hours afterwards.

6. The basket and the sample are then weighed while suspended in water at a temperature of 22o to 32o C.

7. In case it is necessary to transfer the basket and the sample to a different tank for weighing, they should be jolted 25 times as described above in the new tank to remove air before weighing. This weight is noted while suspended in water W1 gm.

8. The basket and the aggregate are then removed from water and allowed to drain for a few minutes, after which the aggregates are transferred to one of the dry absorbent clothes.

9. The empty basket is then returned to the tank of water, jolted 25 times and weight in water W2 gm.

10. The aggregates placed on the absorbent clothes are surface dried till no further moisture could be removed by this cloth.

11. Then the aggregates are transferred to the second dry cloth spread in a single layer, covered and allowed to dry for at least 10 minutes until the aggregates are completely surface dry. 10 to 60 minutes drying may be needed.

12. The aggregates should not be exposed to the atmosphere, direct sunlight or any other source of heat while surface drying.

13. A gentle current of unheated air may be used during the first ten minutes to accelerate the drying of aggregate surface.

14. The surface dried aggregate is then weighed W3 gm. 15. The aggregate is placed in a shallow tray and kept in an oven maintained

at a temperature of 110o C for 24 hours. 16. It is then removed from the oven, cooled in an air tight container and

22  

weighed W4 gm. 17. At least two test should be carried out, but not concurrently.

 

 

OBSERVATION TABLE:‐ 

Sl. No.  Details of sample Sample 1  Sample 2 Sample 3

1  Weight of  saturated aggregate  suspended  in water with  the basket = W1 gm. 

 

2  Weight of basket suspended in water = W2 gm.  

3  Weight of saturated aggregate in water = Ws = (W1 – W2) gm  

4  Weight of saturated surface dry aggregate in air = W4 gm  

5  Weight  of  water  equal  to  the  volume  of  the  aggregate  =  (W3 – Ws) gm 

 

 

CALCULATION  (i) 

 

 

(ii)  

 

 

23  

RESULT  The specific gravity of coarse aggregate ____________. 

 

LIMIT  The specific gravity of aggregates ranges from 2.5 to 3.0. 

 

24  

Solution 9:

AIM   To determine the penetration value of the given bitumen material. 

EQUIPMENT  1. Penetration apparatus 2. Thermometer 3. Time measuring device 4. Transfer dish 5. Water bath 6. Needle 7. Container. 

 

 

FIGURE: 

 

 

 

THEORY  The  consistencies  of  bituminous materials  vary  depending  upon  several factors  such  as  constituents,  temperature,  etc.  As  temperature  ranges between 25º and 50ºC most of the paving bitumen grades remain in semi solid or in plastic states and their viscosity is so high that they do not flow as liquid.  

                      Determination of absolute viscosity of bituminous material  is not so simple. Therefore the consistency of these materials  is determined by  indirect  methods.  The  consistency  of  bitumen  is  determined  by penetration  test which  is a very  simple  test. Various  types and grades of bituminous materials are available depending on  their origin and  refining process.  The  penetration  test  determines  the  consistency  of  these materials  for  the  purpose  of  grading  them,  by measuring  the  depth  (in 

25  

units of one  tenth of  a millimeter or one hundredth of  a  centimeter)  to which  a  standard  needle  will  penetrate  vertically  under  specified conditions  of  standard  load,  duration  and  temperature.  Thus  the  basic principle of the penetration test is the measurement of the penetration (in units  of  one  tenth  of  a mm)  of  a  standard  needle  in  a  bitumen  sample maintained  at  25C  during  five  seconds,  the  total  weight  of  the  needle assembly  being  100gm.  The  softer  the  bitumen,  the  greater will  be  the penetration. The test is conducted as per IS‐1203 for paving bitumen.  

PROCEDURE  1. Soften the material to a pouring consistency at a temperature not more  than  60oC  for  tars  and  90oC  for  bitumen  above  the  approximate softening point and stir it thoroughly until it is homogenous and is free from air bubbles and water. Pour the melt into the container to a depth atleast 10mm in excess of the expected penetration. Protect the sample from  dust  and  allow  it  to  cool  in  an  atmosphere  at  a  temperature between 15o to 30oC for one hour. Then place it along with the transfer dish in the water bath at 25.0o ±0.1oC and allow it to remain for 1 to 1.5 hour. The test is carried out at 25.0o ±0.1oC, unless otherwise stated. 

2. Fill  the  transfer dish water  from  the water bath  to depth sufficient  to cover the container completely. Place the sample  in  it and put  it upon the stand of the penetration apparatus. 

3. Clean  the needle with benzene, dry  it and  load with weight. The  total moving  load  required  is  100±0.25gms,  including  the  weight  of  the needle, carrier and super‐imposed weights. 

4. Adjust the needle to make contact with the surface of the sample. This may be done by placing the needle point with its image reflected by the surface of the bituminous material. 

5. Make the pointer of the dial to read zero or note the initial dial reading. 6. Release the needle for exactly five seconds. 7. Adjust the penetration machine to measure the distance penetrated. 8. Make at least 3 reading at points on the surface of the sample not less 

than 10mm apart and not less than 10mm from the side of the dish.  9. After each  test  return  the sample and  transfer dish  to  the water bath 

and wash the needle clean with benzene and dry it.  10. In  case  of  material  of  penetration  greater  than  225  three 

determinations  on  each  of  the  two  identical  tests  specimens  using  a separate  needle  for  each  determination  should  be made,  leaving  the needle  in  the  sample on  completion of each determinations  to  avoid disturbance of the specimen. 

 

 

OBSERVATION TABLE:‐ 

Readings  Trials Mean Value

26  

1 2 3

Penetrometer  Dial Initial   Reading  

 

 

Penetrometer  Dial Final Reading  

 

 

Penetration Value          

 

 

 

RESULT  The average penetration value of a given bitumen sample is __________ and the grade of bitumen is __________________.  

 

 

S

A

Solution 10

AIRPORT S

0:

SITE SELECCTION

27 

 

28 

 

29 

 

30 

 

31 

32  

Solution 11:

 

33 

 

34 

 

35