Bal O. Efficiency increase of keeping rails economy after reliability indexes.

An object is a process of development of defects in rails. A purpose is an efficiency increasing of rail economy management by optimization of running expenses. Research methods are methods of mathematical, statistical design. Novelty is that mathematical model of life cycle of rail work the track is developed; analytical dependences are set between operating, structural factors and values of intensity of rail refuses in tracks; the criteria of determination of possible level of single refuses of rails are offered at the first time and their legitimate values are set. Results are evaluation criteria of rail durability for the jointless track construction. It is inculcated in the normative documents of Main administration of track economy. Industry branch is a railway transport.