There is a faster, cheaper platform at Tianjin station.
Now express inter-city bullet trains from Tianjin, operated by China Railway High-speed (CRH) on the Beijing-Tianjin Intercity Railway, travel at a top speed of 300-350km/hr, meaning you can connect to Beijing South Station, 114 km away, in just half an hour. - See more at:
Tianjin Station | Beijing Visitor - China Travel Guide