In Greece extended cracking of twin-block concrete sleepers （ties） and fouling of the ballast-bed were observed with implied problems of gauge widening and deterioration of track＇s geometry. This led to a ten-year ...In Greece extended cracking of twin-block concrete sleepers （ties） and fouling of the ballast-bed were observed with implied problems of gauge widening and deterioration of track＇s geometry. This led to a ten-year investigation program, during which a new method was developed for the estimation of actions on track panel as well as of the pressures / stresses that develop under the seating surface of the sleeper on the ballast-bed. Results from the tests performed on the ballast used in the Greek network are also presented, conducted in laboratories in France, Austria, and Greece. The influence of the actions -static and mainly dynamic- on the track response and the stress and strain of the ballast-bed are also discussed as derived from the tests and theoretical analysis.展开更多
文摘In Greece extended cracking of twin-block concrete sleepers （ties） and fouling of the ballast-bed were observed with implied problems of gauge widening and deterioration of track＇s geometry. This led to a ten-year investigation program, during which a new method was developed for the estimation of actions on track panel as well as of the pressures / stresses that develop under the seating surface of the sleeper on the ballast-bed. Results from the tests performed on the ballast used in the Greek network are also presented, conducted in laboratories in France, Austria, and Greece. The influence of the actions -static and mainly dynamic- on the track response and the stress and strain of the ballast-bed are also discussed as derived from the tests and theoretical analysis.
