2.51. Two straights intersect at a chainage of 2500 m with an angle of deflection as 40°. The straights are to be connected by a simple circular curve...

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1. 1.

   Define the term 'radius of curve'.

   Hint

   Think about the center point of a circle.

2. 2.

   What is a tangent length?

   Hint

   It relates to where the straight path meets the curve.

3. 3.

   What is a simple circular curve?

   • A curve with variable radius
   • A curve with constant radius
   • A straight line

   Hint

   Consider the characteristics of a circle.

4. 4.

   True or False: The longer the tangent length, the sharper the curve.

   • True
   • False

   Hint

   Think about how curves connect straight sections.

5. 5.

   A circular curve with a deflection angle of 60° joins two straights. Given the radius is 400 m, calculate the lengths of the tangents and the long chord.

   Hint

   Use trigonometric identities to find the lengths.

6. 6.

   In a design for a roadway, a simple circular curve needs to accommodate traffic at a speed of 80 km/h. Calculate the necessary radius, considering a maximum allowable lateral acceleration.

   Hint

   Remember the safe turning radius at higher speeds.