Please - do I need a China Visa for the following itinerary?

I am a U.S. citizen with a valid current U.S. passport expiring in late 2017. I will soon be visiting Bangkok, Thailand for a 3 week vacation. My flight itinerary returning home is via China Eastern Airlines from Bangkok to Wuhan (3 hour layover) to Shanghai (3 hour layover) and on to my final home destination of Honolulu, Hawaii, U.S.
Is a China Visa required for this trip? Thank you for your assistance.