Travel to Tai'an

I will be taking hi speed train from shenzhen to beijing. but I wanted to stop and visit friends in tai'an. Where would be the best place to change trains to get there fastest? I don't have much time and I want to spend a day in Tai'an. would it be better to go to Beijing and then transfer to Tai'an?? Or is there a stop along the way where I can change to a hi speed train to Tai'an???