I’d driven under this bridge many times and its form would often catch my eye.  The bridge crosses over Interstate 280 between Sunnyvale and Cupertino.   The design is striking which is unexpected for a modern piece of public infrastructure.  I don’t expect California with its near constant budget crises to be building anything but ugly utilitarian designs.   In this case, some creative thinking in using steel saved millions of dollars in construction costs.  My original suspicion was correct though in that Caltrans only permits concrete construction to reduce maintenance costs.  The city of Cupertino had to agree to maintain the bridge to get Caltrans to approve it.     The result is a beautiful piece of architecture.