(Solved): A right-hand circular curve is used as part of the horizontal alignment of a 2-lane, two-way rural ...

A right-hand circular curve is used as part of the horizontal alignment of a 2-lane, two-way rural road. The curve is designed for maximum safe speed of \( 80 \mathrm{~km} / \mathrm{h} \), has a central angle of \( 83^{\circ} 7^{\prime} 28.8^{\prime \prime} \), radius \( =310 \mathrm{~m} \), applied superelevation is \( 4 \% \), land width is \( 3.2 \mathrm{~m} \) and shoulder width \( =1.0 \mathrm{~m} \). The curve starts \( (\mathrm{BC}) \) at chainage \( 0+905.280 \). The straight sections at the approach and leave of the curve are crowned to \( 2 \% \). The entire road section falls on a grade of \( 2.5 \% \). The following additional information is available to you: - Current ADT \( =9000 \) veh/day and annual growth factor in is \( 3.5 \% \) - Perception-reaction time \( =2.5 \mathrm{sec} \) and brakeforce coefficient \( =0.32 \) - Crown runoff length \( =30 \mathrm{~m} \) and superelevation transition assumes one-third rule. 2.1 Calculate the widths of the carriageway and travelled way. 2.2 Determine the ADT after 20 years. 2.3 Calculate \( \mathrm{PI} \) chainage, EC chainage, curve length and tangent length. 2.4 Determine the curve total widening requirement (use articulated bus). (3) \( 2.5 \) Calculate the minimum required stopping sight distance (Hint: do both uphill and downhill calculations).