Experimental comparison of the lateral resistance of tracks with steel slag ballast and limestone ballast materials

Abstract

Extending the use of continuous welded rails by eliminating the weak points (expansion joints) of a railway track especially in sharp curves, which has resulted in increasing the operational speed and axle load of rolling stocks, enhances the special attention to the issue of track lateral resistance. In this regard, the ballast layer interaction with sleepers plays a crucial role in providing the track lateral stability. In many railway projects supplying the appropriate ballast materials has encountered serious restrictions owing to the lack of qualified ore and also their long distance to the project's site. With the development of steel industry, the quantity of production and accumulation of steel slag as a waste material has increased. In recent years, a great deal of attention has been paid to the use of this material as railway ballast. According to the physical and mechanical characteristics of steel slags, such as high specific gravity and the granular roughness respect to the limestone ballast, the usage of slag ballast can improve the track lateral stability. In this research, many field experiments were conducted on tracks with steel slag ballast and limestone ballast materials considering the same gradation. In this matter, several single tie push tests were carried out on both tracks with various ballast geometries. The ballast depth was considered as 30, 40, and 50 cm and the shoulder ballast width was equal to 30 and 40 cm. Moreover, the shoulder ballast height was chosen 0 and 10 cm. Consequently, the lateral resistance of both tracks was measured and compared in the same conditions. In overall, the obtained results confirmed a 27% increase in lateral resistance of track with steel slag ballast respect to that with limestone ballast.

Experimental Investigation on Effect of Winged Sleeper on Lateral Resistance of Ballasted Track

“…Track's resistance against lateral displacements has been measured using different methods [21]. The most conventional methods are single sleeper push test (so-called STPT) and track panel loading test (so-called LTPT(.…”

Mechanical behavior of ballasted railway track stabilized with polyurethane: A finite element analysis

“…Various technical solutions are used to provide the required indicators of stability and reliability of the railway track. These include the optimization of the friction properties of the permanent way by changes in its geometric dimensions, such as thickness and width along the top, as well as the shape of the ballast shoulder itself [4,5]. The type and shape of the ballast material has a noticeable effect on the lateral stability of the railway track.…”

“…The type and shape of the ballast material has a noticeable effect on the lateral stability of the railway track. It was shown in [5] that steel slag ballast has an average of 27% more lateral resistance than a limestone material. Increasing the resistance of ballast to the transverse shear of a sleeper can be achieved by optimizing its shape.…”

“…In the paper [19], the transverse shear forces arising from the sleeper and measured in [4,5,[20][21][22] are compared with similar measurements made after strengthening the ballast shoulder with polyurethane binders. It is found that the formation of the geocomposite from the strengthened by the polymer ballast leads to a significant increase in the contribution of the ballast shoulder to resistance to transverse shear due to the formation of the geocomposite beam.…”

Evolution of Longitudinal Resistance Performance of Granular Ballast Track with Durable Dynamic Reciprocated Changes

“…Continuously welded rail (CWR) tracks have become standard modern track structures [6,7]. e ballast longitudinal and lateral resistance, which is closely related to line stability and rail creeping, is still a major research topic [8][9][10]. e longitudinal resistance values and evolution trend that directly affect the longitudinal line stability, rail bar design plans, rail creeping, and safe service of CWR tracks are of particular importance [11,12].…”