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POKHARA UNIVERSITY Level: Bachelor Semester – Fall Programme: Be Course: Transportation Engineering I Year : 2009 Full Marks : 100 Time : 3hrs. Candidates are required to give their answers in their own words as far as practicable. The figures in the margin indicate full marks. Attempt all the questions. 1. a. b. 2. a. b. 3. a. b. 4. a. b. 5. a. b. What are the different modes of transportation? Explain the role of road transportation in rural development of Nepal. Describe the different stages to be carried out for finalizing the highway alignment. 7 What is sight distance? Derive the relation for the stopping sight distance for a Speed of V KPH and ascending gradient of n%. Calculate the length of transition curve and shift for the following data: Design speed =70KPH Radius of Circular Curve=250m Allowable rate of introduction of super elevation (pavement rotated about inner edge) =1 in 140 Pavement width including extra widening= 7.5m. 7 What is Super elevation? Explain the method of attaining Super elevation. Calculate the maximum allowable speed on a horizontal curve if maximum allowable value of lateral coefficient of friction is 0.15 and rate of super elevation is 0.07. 7 What are the special points to be considered in the aligning the hill roads and why? What is hair pin bend? Write down the design criteria adopted for planning hair pin bends. 7 What are the requirements of highway drainage system? Explain the design of filter material for subsurface drainage system. The maximum quantity of water expected in one of the open longitudinal drains on clayey soil is 0.8m3/sec. Design the cross section and longitudinal slope of trapezoidal drain assuming the 7 1 8 8 8 8 8 bottom width of the trapezoidal section to be 0.8 m and cross slope to be 1 vertical to 1.5 horizontal. The allowable velocity of flow in the drain is 1.2 m/s and Manning’s roughness coefficient is 0.02. 6. a. b. Define the green road. Explain the objectives of green road construction. A specimen of asphaltic concrete has a height of 6.35 cm an diameter 10.2 cm. The weights of compacted specimen in air and water are 1180.5 gm and 678.6 gms respectively. The analysis of the specimen yielded the following: Material Bulk Specific Gravity Mix composition (% by wt. of mix) Bitumen 1.02 6 Coarse Aggregate 2.6 54 55.3 Fine Aggregate 2.72 33.5 36.8 Mineral Filler 2.7 Total 7. 8 Aggregate Composition( % by wt. of total aggregates) 6.5 7.9 100 100 Calculate (i) Bulk density of specimen from dimension and immersion test (ii)Air voids percentage in compacted mix (iii) VMA (iv) VFB Write short notes on (Any Two) a. Penetration test of bitumen b. Abrasion value of aggregate c. Marshall stability test 2 7 5×2