ABSTRACT
In the last two decades China has added more than 10,000 high-speed railways to its national rail network. These railways cross varying environmental and ground conditions which sometimes pose significant challenges to the safe and smooth operation of high-speed trains. As these projects are all internationally pioneering, the interaction between railways and their environments are not always well understood. A representative example is the recently constructed railway between Harbin and Dalian in north-eastern China. The railway spans 920 km and a substantial portion is constructed on formation or embankment on seasonally frozen ground. Formal operation of its service commenced late 2012. The observed heave in the 2012/2013 winter is around 5 mm on average and larger than 20 mm at maximum. The maximum heave is well over the design tolerance for high-speed track displacement. As a consequence, the design speed of 350 km/hour is substantially reduced, to 180 km/hour in winter and 300 km/hour in summer seasons.
