Question

Question 5 (20 marks) A two-lane highway (one 3.6-m lane in each direction) goes from normal crown with 2% cross- slope to 6% superelevation by means of a spiral transition curve. The spiral curve is 60 m long. If the superelevation is attained by rotating the road section around its centreline, draw a cross section of the road at 10, 20 and 50 m from TS. (horizontal distances, grades, and elevated heights must all be labelled in the drawing)

Answer 1

0 Angin Given that of : 7.2m V. 100 km 100 km / hor width two lane highway design speed coross slope slope changing from 2% to 6% Length of spiral cove : Gom TIL TTL nomal aore nordcore Super clevotion TTL TTL 5.C C.S Tis SIT

where T.S ps Tangent lo the spisal S.C PS spinal to curve CS Ps corve to spisal to tangent ST Ps Spiral Supor elevation altainment to ravelled way catoled Labout cente lire Normal Tangent Fuell superelenie coown Super Elevation runout Oul- side edge of poverenn - 'Nomal poctine act) profile K - - - INSTOECOGE | OF PAVEMENT Full super elevation golo 0.02 0.02 0.02 0.04 0.021 0.02 pavement Revolved about centere line

NOTE : ANGOLAR BREAKS 10 119 PODIATT17 POUND STOWN BY OMHED LINE ROUNDINGI