Experimental section of railway track on a reinforced concrete continuous slab

In 1975, on the Madrid - Barcelona railway line, an experimental section without ballast was constructed with a view to obtaining a track which would be of sufficiently good quality for use by fast trains while costing less to maintain. The 4,IOO-m-long section was located on a part of the line where the 9ubgrade consisLed of a variety of soils, so that the behaviour of each of them could be observed. The paper deals with the initial data for the structural design of the reinforced concrete slab, the special treatments applied to the subgrade, the composition and properties of the concrete, the construction methods, etc. Part of the conventional railway construction plant had to be modified for this type of track and new versions were designed when appropriate tests had been performed. The experience gained with operating this track over the past ten years has been backed up by periodical surveys and by specific tests (elasticity of the track, verification of the theoretical model, noise measurements and comparison thereof with the noise emitted from conventional tracks, etc.). So far, this section of track has required no maintenance work.