49106 Road Engineering Practice First Assignment Autumn 2017 Assignment due at 9.00 am on 1 May 2017 (Electronic submission) Question 1 (4 marks) A section of a major rural highway is under design. It is a divided carriageway and has the following cross section for each carriageway: Left shoulder = 2.5 m Median shoulder = 1 m 2 x trafficked lanes = 3.5 m There is dense vegetation adjacent to the left shoulder. This vegetation forms an obstacle to vison around left curves. The road has a left curve with a horizontal radius of 650 m with 3% superelevation. The grade is 1% downgrade (-1%) The proposed design speed is 110 km/hr. Check this horizontal curve design and horizontal stopping sight distance for cars. Use the appropriate values in the RMS Austroads Guide Supplement dated 12 August 2015. Is additional shoulder widening or clearing of the vegetation required? Is so, how much is required? Question 2 (2 marks) Explain how you would decide on the appropriate width of a shoulder for a rural road. In your answer cover the critical issues and discuss the benefits of bitumen sealing of that shoulder. Question 3 (2 marks) Explain how large heavy vehicles such as B Doubles and semi-trailers affect road design in urban areas When designing a rural road connecting two major towns, what design and checking vehicles would you use? In your answer provide a brief explanation. Question 4 (4 marks) Constructability is an important feature of a good road design. What are the major constructability issues you would consider in the design of a road in an urban area? The length of your answer should be 300 words (plus or minus 10%). Question 5 (2 marks) What do you understand by the term \"safe system approach to road design\"? Question 6 (4 marks) The two types of asphalt mix commonly used in Australia are Dense Graded and Fine Gap Graded Asphalt. For these two mixes, describe their main features, when they should be used and describe their disadvantages. Question 7 (2 marks) Name four major components of asphalt and describe how they contribute to its performance as a pavement