Experimental investigation on the application of quick-hardening mortar for converting railway ballasted track to concrete track on operating line

The ballasted track system has been widely adopted on conventional railways due to its ease of construction, but its key shortcoming is its need for frequent maintenance. In recent years, with the growing demand for railway vehicles capable of higher speeds and capacities, the concrete track is becoming more popular due to its high rigidity and relatively low maintenance. A fast converting technology was developed in this study to transform the existing ballasted tracks into concrete tracks using the developed quick-hardening mortar, which has high fluidity and strength development at an early stage, such that it could minimize the interruption of train operation. To assess the applicability of the developed mortar in the field, durability, fluidity and strength development of the mortar were characterized. The developed quick-hardening mortar was applied to a 52 m-long existing ballasted track of an operating line, and structural stabilities under moving train loads were evaluated. Experimental results showed that the track conversion was successful with the quick-hardening mortar, and the concrete structures proved to have excellent performance compared to the existing ballasted track.