How to model skew bridges?

Thanks！This solution is helpful, but troublesome. Hope that this function can be optimized in future software updates.

Hi, I've been looking at this and it seems the best solution for your case should be: 

1. Define several supports lines for the deck transitions;

2. Apply one deck between each two consecutive support lines;

3. Create fictitious alignments for defining the thickness variations;

4. For each deck use Point Control definition and select the fictitious alignments for the horizontal distances.

5. For vertical distances use variable constraints.  

Let us know if you have any other question.