Taming the “Rock Maiden” with precast concrete columns
The Styrian municipality of Radmer an der Stube is located in an idyllic high valley east of the Gesäuse National Park. The access road to the popular excursion site had to be closed repeatedly, however, due to the risk of falling rocks. In the future, passers-by will be protected from souvenirs presented by the “Rock Maiden” due to a new rockfall protection system that is unique in Austria. Several years earlier, nets had been installed to catch rocks falling from the steep rock face called the “Rock Maiden”. Since the L127, the so-called “Radmer Road”, winds through difficult topographical terrain in this area, however, effective rockfall protection measures were virtually impossible. In addition to the executing engineers and construction companies, the Institute for Foundation Engineering and Soil Mechanics at the Graz University of Technology was commissioned to analyze the actual hazard potential using simulation programs. As an expert for special precast elements, Rauter has built an excellent reputation throughout Austria. The subsidiary of the Kirchdorfer Group demonstrated exceptional skill in the project involving the so-called “Rock Maiden”.
15 impressive precast concrete columns
A total of 15 impressive precast concrete columns were inserted into the foundationsprepared on site. The huge rockfall protection netting is now stretched between the cantilever arms attached to the 28-ton columns, covering the entire width of the road. Two-meter high precast walls were installed between the columns. Wilfried Klade, Managing Director at Rauter, says: “No other precast producer in Austria was willing to take on the challenge of producing this type of columns. Implementing the project was extremely challenging, in particular due to the complex geometry and unique design, but we are all the more proud today that we were able to tame the ‘Rock Maiden’ and avert the hazard of falling rocks.”
Andreas Kammersberger from the state of Styria emphasizes the special nature of the project: “It doesn’t happen very often that rockfall protection netting is installed in this way next to and above a public road on such impressive precast concrete columns. Aramid fabric is used primarily in military technology, for example in bulletproof vests or light vehicle armor, and to my knowledge, we are the first to have used this material in this type of application.”
