Tianjin highway system mainly consists of national highway 102, 104, 105, 112, 205, 307, 341, and several expressways like Beijing – Shenyang, Tianjin – Tangshan and Beijing – Tianjin, etc. It takes about 1.5 hours or 4 hours respectively from Tianjin to Beijing or Shijiazhuang.
There are many a long-distance bus station in Tianjin, among which Tianhuan Long-Distance Bus Station located in Nankai District, mainly serves buses of the inter-provincial passenger transport, to Beijing, Shanghai, and Hebei, Shanxi, Shaanxi,Inner Mongolia, Zhejiang, Jiangxi and other places, whereas other stations provide buses mostly to Tianjin suburban areas and neighboring provinces and regions.
From Tianjin to Beijing Capital International Airport
Passengers can take a coach direct from Tianjin Tianhuan Long-Distance Bus Station (天环客运站) to Beijing Capital International Airport. The trip takes about 2.5 hours. The departure interval is 1 hour from o4:00 to 06:00 and that for period from 06:00 to 18:00 is 30 munities. Tianhuan Bus Station is located in the crossing of Hongqi Road and Anshan West Road, Nankai District (南开区红旗路与鞍山西道交口处), and the telephone numbers are 022-6455 8718 and 022-8433 5878.
source & credit – http://www.chinahighlights.com/tianjin/transportation.htm