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1 VI SEMESTER FINAL EXAMINATION-2003 Q. [1] [a] Draw a right angle four-arm intersection of two roads and show various conflicts points if [a] both roads are with way movements, and [b] one road is with twoway movement and another road is with one-way movement. Classify the types of conflict. [8] [b] What are the uses of measuring of spot speed, journey time and delay studies in traffic engineering? [8] Q. [2] [a] Which type of parking facilities, on-street or off-street parking do you recommended in the city area of Kathmandu valley? Given reasons. [5] [b] Road A is 13.5m wide and Road B is 10.5m. An isolated signal with pedestrian indicators is to be installed at right-angled intersection. The heaviest volume per hour for each lane of Road A and Road B are 250 and 200 respectively. The approaching speeds for Road A and Road B are respectively 60Km/hr and 45km/hr. Design the traffic and pedestrian signal timings. [Take amber periods for yellow light signal as 2-4 seconds and pedestrian walking speed of 1.2m/sec.] [10] Q. [3] [a] What are the problems usually encountered in flexible and rigid pavements? [10] [b] You are required to design the pavement, as it is proposed asphalt concrete on the surface and other layers are as follows: [6] [i] Minimum thickness of asphalt concrete on surface course =50mm. [ii] Crushed stone base of CBR value = 80% [iii] Crushed run gravel sub-base of CBR value = 20% [iv] 85 th percentile CBR value of sub-grade soil = 6% The existing road is a double lane of 7m width and caters a present traffic ADT of 600 commercial vehicle per day with an annual growth of 6.5%. Design the pavement section using CBR method (revised IRC). The road is to be designed for 10 years and it is expected to be completed within 2 years form the last traffic count. Q. [4] [a] Write down the various techniques of soil stabilization. [8] [b] Write down the construction procedure of bituminous surface dressing. [8] Q. [5] [a] Write down the necessity of periodic maintenance of the road in Nepal. [8] [b] How earthen roads are maintained? Explain briefly focusing on district and village roads. [8] Q. [6] [a] Write down the classification of bridges and components parts of a bridge. [8] [b] What do you meant by.? Explain briefly. [8] Q. [7] Write short notes on (any FOUR): [4 4=16] [a] Fatigue Cracking [b] Rutting [c] Guide bund and spur. [d] Importance of Ventilation and. [e] Emergency Maintenance. Downloaded from /1

2 VI SEMESTER FINAL EXAMINATION-2004 Attempt any TEN questions. Q. [7] is compulsory. Q. [1] What are the different vehicular characteristics which affect the design of road. Explain briefly them. [8] Q. [2] What do you understand about traffic control devices and their types. Write down the advantages and disadvantages of traffic signals. [8] Q. [3] What are the main factors which causes the road accidents and preventive measures which will help for the reduction of road accidents. [8] Q. [4] What are the distinct phases of a parking survey? What information is obtained form each? [8] Q. [5] Write down the necessity of periodic maintenance of the road in Nepal. [8] Q. [6] Criticize the following recommendation of a town engineer regarding lighting effects in a town of a population of [8] [a] Mercury vapor lamps for residential area. [b] Sodium vapor lamps for shopping areas. [c] Filament lamps for highways. Make your own recommendation, where you disagree, starting your reasons. Q. [7] Design the asphalt concrete pavement with the following information: [8] [a] Minimum thickness of asphalt concrete is 50mm. [b] Stone aggregates base with CBR value 85%. [c] Gravel sub base course with CBR value 25%. [d] Sub grade soil compacted with CBR value 7%. The road is with present traffic ADT of road is 500 vehicle per day with an annual growth rate of 7%. The road is to be design for the 10 years and is expected to be completed within 4 years. Q. [8] Discuss about different design elements in highway embankment and excavation. [8] Q. [9] Write down the construction procedure for bituminous surface dressing. [8] Q. [10] Write down the construction procedure for the cement concrete payment. [8] Q. [11] Discuss about the causes of failure of the bituminous pavement and maintenance works of bituminous surfacing. [8] Downloaded from /2

3 VI SEMESTER FINAL EXAMINATION-2005 Q. [1] [a] What is Traffic and what are its characteristics? Explain in brief the speed studies by using synchronized watch method and presentation of the data obtained form it. [3+5] [b] Do you consider the Nepalese roads (both rural and urban roads) are safe? If not, what measures would influence your judgment in preventing the road accidents? [8] Q. [2] [a] What are the various types of traffic control devices that are used in the intersections? Explain different type of roadside signs drawing at least one example of each. Find out the total conflict points in a four arm at grade intersection, N-S direction (two lane, one way flow) and E-W direction (two lane, two way flow). [1+3+4] [b] A signalized junction of R and Y roads is to be itmed by an isolated signal with pedestrian indication Roads R and Y are 12m and 9.6m wide respectively. The heaviest volume per hour for each lane of road R and Y are 450 and 300, respectively. The approach speeds are 60 and 45 Kmph, for R and Y roads respectively. Design the timings of traffic and pedestrian signals. Assume suitable data if necessary. [8] Q. [3] [a] What do you mean by highway intersection and what are its types? Under what circumstances provision of roundabout is justifiable? Explain the factors to be considered in its design. [2+1+5] [b] Discuss different method of road lighting with respect to (i) Silhoutte effect, (ii) Reverse Silhoutte effect, and (iii) Discernment by surface detail. What are the various factors to be considered in the design of effective highway lighting system? Explain. [4+4] Q. [4] [a] Explain Flexible and Rigid pavements and bridge out the points of differences. [2+4] [b] It is intended to design a flexible pavement for a specified stretch o-f an existing two lane road form the following information: (i) Current Traffic of 80KN equivalent single axle load = ESAL. (ii) Design period = 10 years. (iii) Construction period = 12 moths form the last traffic census. (iv) Traffic growth rate = 7% (v) Design resilient modulus of sub-grade soil form 7 samples collected = 26MPa. (vi) Elastic modulus of asphalt concrete for surface course, E ac = 2500 Mpa (vii) Elastic modulation of bitumen treated base, E b = 1200 Mpa. (viii) Elastic modulus of granular sub base (CBR>20%), E sb = 125Mpa. You are required to design the pavement from Asphalt institute Method (AIM) Draw the cross section of final pavement layers considering the minimum thickness of asphalt concrete on surface course as 40mm. [10] Q. [5] [a] A village road is to be paved by using Water Bound Macadam (WBM) type of construction. Give the detailed method of construction and the materials required for it. [6+2] [b] What do you understand by penetration macadam? What are the various materials used and what should be Downloaded from /3

4 their requirements? Describe the methods of construction of a penetration macadam road. [2+2+4] Q. [6] [a] Enumerate the types and causes of flexible pavement deficiencies. As a divisional Engineer of Department of Roads, what are the various types of roadways maintenance works that you put forward for Muglin Narayangadh section of Nepal? [3+5] [b] What are the requirements for an ideal bridge and factors to locate it? Explain briefly the different methods of tunneling. [4+4] Q. [7] Write short notes on (any FOUR): [4 4] [a] Road user characteristics. [b] Organization and Destination Study. [c] Grade separated intersection. [d] Stress in cement concrete pavement. [e] Prime coat, Tack coat and Seal coat. [f] Bridge classification. Downloaded from /4

5 VI SEMESTER FINAL EXAMINATION-2006 Q. [1] [a] Why is the origin and destination study carried out? How is O & D data collected? [8] [b] What is a rotary intersection? What are its advantages and limitations in particular reference to traffic conditions in Nepal? [8] Q. [2] [a] What are the various aspects to be investigated during parking studies? [6] [b] An isolated signal with pedestrian indication is to be installed on a right angled intersection with road P 18m wide and road Q 12m wide. The heaviest volume per hour for each lane of road P and road Q are 275 and 225 respectively. The approach speeds are 60 and 45 kmph, for p and Q respectively. Design the timings of traffic and pedestrian signals. [Take pedestrian walking speed of 1.2m/s and amber periods of 4 and 3 seconds] [10] Q. [3] [a] Explain flexible and rigid pavements and bring out the points of difference. [6] [b] The pavement structures of an asphalt concrete is to consist of the following layers: Minimum thickness of asphalt concrete is 5 cm Well graded gravel of CBR value = 95% Fairly graded gravel of CBR value = 20% Compacted soil of CBR value of sub-grade soil = 4% The road is to cater a present ADT of 3500 heavy vehicles with an annual growth rate of 7%. The pavement construction is to be completed in 2 years form the last traffic count and the road is designed for 15 year period. [i] Design the payment section by CBR method as recommended by IRC. [ii] Suggest alternate design with out using fairly graded gravel. [iii] Considering the above results, discuss the limitation of CBR method of payment design. [10] Q. [4] [a] What are the characteristics of an ideal abridge? [10] [b] How is drainage controlled and ventilation achieved in tunneling? Explain. [8] Q. [5] [a] Discuss the construction procedure of penetration macadam. [8] [b] What are the various techniques of soil stabilization in road construction technology? [8] Q. [6] [a] Explain the typical flexible pavement failures with sketches. [8] [b] How is water Bound Macadam Roads maintained? [8] Q. [7] Write short notes on (any FUR): [4 4] [a] Thirtieth highest hourly traffic volume. [b] Classification of bridges. [c] Mud pumping [d] Interface Treatment [e] Temperature stresses. Here Graph is not included. Please refer original old question. Downloaded from /5

6 VI SEMESTER FINAL EXAMINATION-2007 Will the signal timing diagram be suitable for present situation of intersection? If not, show new signal timing diagram. Also, Design isolated signal with pedestrian indication. (Assume other data suitably, if necessary). A [8] B Q. [1] [a] What do you mean by traffic regulation? Explain four different traffic regulations methods in detail. Write names of different types of traffic signals. [2+4+2] [b] Define space mean speed. What are the purposes of speed studies? Explain method of measurement of spot speed by Enoscope method. [2+3+3] Q. [2] [a] What do you mean by condition diagram? Explain in detail three groups of measurements that can be taken to reduce the rate of traffic accident and its severity. [2+6] [b] The signal timing for certain intersection is shown in Fig. 2[b] below. G A=50 AA=5 R A=29 R B=55 G B=25 AB=4 The recent traffic study conducted on that intersection gives following data. Road A Road B Approach Speed of vehicles Traffic Volume (vehicles/hr) Width of Road (m) Pedestrian Speed (m/sec) 1 1 [b] Draw neat diagram of Bridge showing its different Component pats. List down the preliminary data to be considered during the selection of bridge site. [4+4] Q. [4] [a] What are the factors controlling the design of pavements? Explain in detail. [6] [b] A rigid pavement of 23cm thick was provided on certain section of road having road width 12m. The longitudinal joints are provided at the centre line of road and transverse joints are at the interval of 8m Calculate worst combination of stresses (using Westergaard s stress equation) for edge region, interior and corner region of slab, assuming traffic load of 5100 kg having tire pressure of 720KN/m 2. (Temp. different in pavement = 13 o C K = kn/m 3 ; E = kg/cm 2 ; µ = 0.15 α = / 0 C; unit length of Concrete = 25kN/m 3 ; Coefficient of friction = 1.5). Assume other data suitably, if necessary. Downloaded from /6

7 VALUES OF L X /I AND L Y /I Q. [5] [a] Describe construction procedure of Double Bituminous Surface Treatment including the properties of materials (aggregates, bitumen etc), plants and equipment needed, construction steps and the test sued for quality control. [8] [b] Explain different types of maintenances work carried out on bituminous surface. Give neat sketches whenever necessary. [8] Q. [6] [a] List out different method of soil stabilization. Discuss the method of construction of Mechanical Soil Stabilized roads including materials, equipment construction steps and tests to be conducted. [1+7] [b] Differentiate between Road maintenance and Roadside maintenance. Explain each type of road maintenance in detail with suitable examples. [8] Q. [7] Write short notes on (any FOUR): [4 4=16] [a] Design of lighting units [b] Origin and Destination study. [c] Frictional stress in concrete pavements. [d] Joints in Rigid pavements. [e] Methods of providing fresh air inside Tunnels. Downloaded from /7

8 VI SEMESTER FINAL EXAMINATION-2008 Q. [1] [a] Define traffic Engineering. What are the major road user characteristics? Describe their influence on the human-vehicle-environment system. [2+3+2] [b] Find out the total Conflict Points and type for the intersections given in the figure below. [9] A a) B A b) Q. [2] [a] What are the different causes of traffic accidents? Discuss briefly. [6] B [b] The average normal flow of traffic on cross roads A and B during design period are 600 and 500 PCU per hour, the saturation flow values are estimated as 1600 and 1300 per hour respectively. The all red time required for pedestrian crossing is 11 secs. Design two phase A B D c) C traffic signal by Webster s method. (Assume amber time 2 and 3 sec. for roads A and B respectively). [10] Q. [3] [a] List out the points of difference between flexible and rigid pavements. Make sketches for both types of pavements. [8] [b] Design the flexible pavement by CBR method recommended by IRC; using following data: CBR value of sub-grade soil: 6% Poorly graded gravel with CBR 25% Well graded gravel with CBR 90%. Take the minimum thickness so wearing course as 5cm. The present traffic volume is 700 commercial vehicles per day and growth rate is 7%. Take construction period of the pavement as 12 months and with 12 years of life period. (Use the Chart given below). [8] Q. [4] [a] Describe the construction procedure of penetration (grouted) Macadam roads including the requirements on materials, construction steps, plants and equipment and the tests for quality control. [8] [b] How the ventilation and drainage problems are managed while tunneling? [8] Q. [5] [a] What are the various techniques of soil stabilization in road construction technology? [8] [b] What are the assumptions made by Websterggrd for analyzing rigid pavement? Calculate the radius of relative stiffness of 15cm thick cement concrete slab form the following data: [8] Modulus of elasticity of cement concrete = 2, 10,000kg/cm 2 Poisson s ratio for concrete = 0.13 Modulus of sub-grade reaction K = 3.0 kg/cm 3 Downloaded from /8

9 Q. [6] [a] What are the usual damages in water bound Macadam roads and describe the techniques of maintenance of such types of roads? [8] Q. [7] Write short notes on any FOUR: [4 4=16] (a) Enoscope method. (b) Design factors of highway lighting. (c ) Prime Coat (d) Mud pumping. (e) Warrants of signalization. Downloaded from /9