Today we're going to learn about bearings and how they affect road design. Bearings help us understand the direction of each road segment. Can anyone tell me what a bearing is?

Exactly! Bearings are usually given in degrees from the north direction. For instance, AB has a bearing of 103°29'24". Can someone explain why knowing this is important for connecting road segments?

Great point! Accurately calculated bearings minimize abrupt changes in direction and improve driving comfort and safety. Remember: bearings = angles from the north, think of them as a compass that guides our road design.

Now, let's talk about chainages. The through chainage for point B is 1097.65 m. What do you think a chainage represents?

Absolutely! Chainages help us measure where to place curves accurately. Now, with the horizontal distance BC being 708.32 m, how would we find the chainage for the tangent points after calculating the curves?

Correct! For the first curve of radius 1500 m, we determine the tangent points by adding and subtracting the lengths and chainages correctly. This lets us set up the proper alignment for the road.

Let’s figure out the specific curves connecting our segments. We have to connect AB to BC with a 1500 m radius curve and BC to CD with a 900 m radius curve. How do we start this calculation?

Exactly! Each tangent point is critical for determining where our curves begin and end. Once you get the tangent points, the actual curve lengths can be derived using the radius and angle we calculated. Who can recall how we determine the tangent length for a curve?

Precisely! Utilize the formulas you learned in previous lessons, and don't forget to keep track of your units.

Finally, why do you think these calculations are important for urban planning and safety?

Exactly! Proper planning avoids accidents and ensures smooth traffic flow. These are not just numbers; they represent real-life safety measures. Let’s remember: accurate calculations lead to safer roads.