DYWI® Seal Waterproofing System protects Torrent Embankment following a Landslide
On June 18th 2011, a landslide on a section of railroad track near Innsbruck, Austria was caused by heavy rain. The landslide penetrated a protection gallery on a side track underneath the Martinswand, a mountain face north-west of Innsbruck. The train that was passing at the time had to be stopped because of the debris penetration.
As an emergency measure, the channel embankment of the torrent above the gallery had to be repaired. A continuous shotcrete channel was built above the protection gallery and the cavity above the gallery was filled with lean concrete.
The ensuing repair measures included the construction of a new connection to a forest road, a paved channel on the talus area and a guiding channel at the protection gallery. Additionally, some temporary construction needed to be carried out for collecting and draining off the water in case of new rain showers. A total of 1,200m3 of rock and debris had to be moved for the construction work.
In order to ensure the stability of the channel, new abutments were built through the shotcrete channel. These abutments were embedded 1.5m deep in the talus and anchored to the bedrock underneath using 8m long Type R38-500kN DYWI® Drill Hollow Bar Bolts.
Considering the prevailing soil conditions and the remoteness of the construction site, the self-drilling and piecewise installation of the hollow bar anchors proved to be a great advantage.
Afterwards, the DYWI® Seal Waterproofing System was applied to the shotcrete layer of the channel to prevent the penetration of water into the subjacent talus. In order to achieve a force-fit connection between the base layer and the pavement of the channel, reinforcing bars were drilled through the waterproofing layer.
The self-healing effect of the DYWI® Seal Waterproofing System was the crucial reason for using the system because the drilling of reinforcing bars through the DYWI® Seal waterproofing layer did not cause any leakage. Due to the steep surroundings, the light weight of only 0.5kg/m2 was another advantage both considerably facilitating transportation and handling on site. Furthermore, the ease of installation without the need for any additional welding equipment was much appreciated by the parties involved.
Blocks of stone and lean concrete were then placed directly above the waterproofing layer in order to stabilize the channel and protect it from abrasion.