Experimental investigation of the production of sleepers from concrete that contains blast furnace slag

Abstract

Sleepers play an important role in determining the performance of rail tracks. The level of this importance can be gauged by noting the large number of sleepers that are located on railway tracks (1700 sleepers per kilometer of main line track). Reducing the life cycle costs of railway sleepers, as a result of decreasing construction, maintenance and operation costs, can have a significant economic effect on the cost of operating track. In this regard, the use of novel materials to construct high-strength sleepers is of considerable interest. Blast furnace slag, especially iron slag, can be crushed and used as an aggregate in the concrete used to produce sleepers. In the present study, slag and limestone sand was used to create a slag-containing concrete that was subsequently used to produce sleepers. The results of laboratory tests on slag-containing concrete showed a 46% increase in compressive strength compared with non-slag-containing concrete. The ratio of tensile to compressive strengths of all the slag-containing concrete samples varied between 0.06 and 0.087, which is comparable to the range of 0.1 to 0.15 for non-slag-containing concrete. Negative moment tests performed on sleepers manufactured from slag-containing concrete required a 30% increase in the vertical load to initiate the first crack compared with a sleeper produced from non-slag-containing concrete. These preliminary results suggest that a new generation of high-strength sleepers can be created; the long-term efficiency of this type of sleeper will need to be confirmed by durability tests and practical use.