Research methods: Through making analyses of the structure，the mechanics calculation model is established for rigid structure continuous beam，with which to calculate the expansion force. Through making analyses of the structural stability the research is done on the development of reinforcement device for the jointless track on bridge.
Research results: The suitable reinforcement device-lateral resistant has been developed for the jointless tracks on subgrade and bridge，so the stability of jointless track can be calculated with the tested resistance.
Research conclusions: For rigid structure beam，the expansion force can be calculated by establishing calculation model according the structure of it. The tested data should be used as calculation parameters，for which the more important thing is to test vertical and lateral resistances on site. The influence on the deformation of beam by the pier becomes larger with increment of rigidity of the pier and the influence becomes small when lateral rigidity on the pier top is less. Although the lateral resistant is easy to make，handle and install } but it plays great role in ensuring the stability of jointless track.
2007, Vol. 24 
