MC-Ballastbond – a Swiss success story
MC’s MC-Ballastbond product system comprises resins specifically developed for the bonding of ballast. They serve to stabilise and consolidate ballast, securing both ballast surfaces and ballast beds during track construction work. The product system has a particularly good “track record” in Switzerland.
Ever faster travel speeds and increasing axle loads in rail traffic are also adding to the demands placed on permanent ways and ballasted superstructures. A tried and tested means of stabilising the subsoil is the bonding of ballasted areas. MC has specially developed the MC-Ballastbond product system to stabilise ballast by adhesion and to secure ballast surfaces and ballast beds during track construction work. MC-Ballastbond 60 is an epoxy-based, low-viscosity, firmly solidifying adhesive duromer resin for use under dry conditions which achieves very high strength values. With MC-Ballastbond 70, MC has developed a low-viscosity polyurethane-based duromer resin that can also be applied in wet conditions. It penetrates into the ballast bed and bonds the aggregate at the points of contact, rapidly increasing bed strength while maintaining its drainage capacity. It is also a flame retardant and has no impact on the soil or ground water. The bonded ballast can also be better cleaned by automatic machines without particles being sucked in by the vacuum action.
In Switzerland, the years of intense marketing work performed by the specialist consultants of MC and applicator Hürlimann Railtec AG led to a series of promising deployments of the system. The considerable successes achieved were due in part to a spraying robot developed by Hürlimann which travels on the tracks over a fixed route and sprays MC-Ballastbond 70 onto the ballast bed in the areas required. The results have been excellent: The resin gets evenly distributed, the amount of material can be matched to the exact requirements of the application, and the technology is such that long distances can be quickly covered, thus minimising line closures/possessions. MC-Ballastbond 70 also met SBB’s (Swiss Rail) very high environmental requirements. It has no negative impact on soil and groundwater, and investigations have also shown that cleaning sludge from areas with bonded ballast can be disposed of in the same way as that from non-bonded ballast areas.
MC-Ballastbond for more speed
On the SBB route between Effretikon and Kempthal, part of the very busy line between St. Gallen and Zurich, bonding was carried out on a twin track layout, as provision of a conventional ballast shoulder for additional support would have resulted in countless track closures for several weeks. Thanks to MC-Ballastbond, the entire route was consolidated in a single night! Another success story is that of the SBB entry into Lugano Central. Providing a key north-south link, the curved section is also heavily used by both passenger and freight trains. In the course of the installation of seepage pipes, the critical outer area of the curve was bonded with MC ballast bond. Following the installation work, the SBB carried surveyed the area with no indication of movement in the ballast bed!
The SBB is satisfied with MC-Ballastbond in every respect and will continue to use the system. This example from Switzerland also shows just how successful cooperation based on true partnership with an imaginative applicator can be.