Joint venture leads to an innovative bedding system with elastic joint sealants for modern track construction

The requirements of modern track construction in association with the increased demands in user comfort for disabled access and safety has necessitated the development of new laying techniques. From the initiative of the public transportation services in Dresden and against the background of the need to renovate the historic Postplatz, many points have been pondered anew jointly with the Technical University of Dresden and SCHOMBURG GmbH & Co. KG. All four modes of transport are to comply.

The Postplatz is one of the most important places in Dresden’s town centre and a crucial traffic junction for public transport. The county town of Dresden has decided to press ahead with the redesign of the plaza within the scope of the overall urban concept. The requirements for fixing in the rail areas were very demanding. They were concerned with guaranteeing the fundamentals of the term “rigid rail”, to ensure a durable, stable bond between concrete support and the paving in the rail area. At the beginning of 2004 the goals of a joint project were agreed between the DVB (Dresden public transportation services) and SCHOMBURG GmbH & Co. KG in order to achieve the profile of requirements within the allotted time span – end of the civil engineering works mid 2006. The Technical University of Dresden was called in with the participation of Professor Jordan in order to introduce considerable scientific aspects to the project. Through the support of all participants a construction method was developed that together with the composite strengths achieved formed a building classification that previously had not existed.

The patented “Dresden Joint System (FSD)” permits a professional implementation with experienced skilled craftsmen. In addition maintenance of the joints is possible with the system. The poured joint material impresses with a feasible total deformation of up to 35% and a recovery of > 80%. With track curves with a radius of < 75 m the three dimensional stresses of the rails and the sinking of the rails is dissipated safely in the joint. Dynamic “sine stress” (= deflection of rail downward from > 0.7 mm) is permanently cushioned. Due to the long waiting intervals a longer period of use arises. Although a new system interacting with an array of further contracts has to be declined, the timescale for approx. 6000 m² can be achieved – just in time deliveries from the production units in Detmold and Halle an der Saale. Since mid October lower temperatures and rainfall have hampered construction work. Enclosures and heating of the work area has ensured the continuation of the work.

Up to now 756,000 kg of INDUCRET-VK-Bettungskleber and 226,000 kg of INDUCRET-VK-Fugenkleber have been called-off and installed. For elastic flood jointing approx. 20,000 litres of INDUCRET-VK-Fug-TKF-25 have been used so far. Up to today this represents about 60% of the total quantity planned. The heated enclosures permitted all measures to proceed uninterrupted. The construction in the core area of the Postplatz was planned under the guidelines of the county town of Dresden, whereby the trafficked area in the vicinity of the tracks were to be constructed with large granite setts. The Postplatz is served by seven tram and three bus routes. The double stop for tram and bus are 90 and 100 m long respectively, are covered and have disabled access. The area between the two stops in the Wildsruffer street and Wall street is spanned by a glass roof that is reminiscent of a butterfly.

The public transportation services in Dresden, as developer, together with the county town of Dresden started the construction of the Postplatz on 30th May 2005. Building costs are estimated to be over 40 million Euros.