(1) Considered briefly is the history of concrete crosstie development in France. Failure of some crossties in 1973 led to determination of the failure modes and a rigorous analysis of the service load limits to be taken into account. New crosstie designs evolved from this investigation. Technical specifications and acceptance tests for crossties fabricated according to the new design criteria are described. New-concept crossties under current assessment are also described.
(2) the reasons for the adoption of the concrete crosstie by Ferrocarriles Nationales de Mexico (National Railways of Mexico) are presented. Details of manufacture and testing of these crossties are described. Specifications for concrete crossties are presented. Consideration is given to the performance of crossties and fasteners under service conditions. Some causes of crosstie failure are identified.