Foundations of the Gothenburg Cable Car Towers - A Geotechnical Feasability Study for Two Cable Car Towers on Deep Deposits of Soft Clay

Abstract

To prevent a possibly overburdened public transit system, a cable car was supposed to be built in Gothenburg, a city largely situated on deep deposits of soft clay. The soil conditions together with the large and heavy cable car towers, results in a geotechnical challenge. The two cable car towers investigated in this Thesis, are located at Järntorget and Lindholmen. For the towers to be able to stand stable on the clay, it is essential with a suiting adequate foundation. In this Thesis, an investigation to find a suitable foundation for the towers is conducted by gathering information from literature, such as scientific papers, reports and books. Calculations on geotechnical and structural capacity is performed as well. It is found that concrete displacement piles will be the best option for the foundation of both towers. A sustainability aspect is considered in the Thesis and it is shown that longer piles require less concrete with fewer piles and are, therefore, more sustainable than shorter piles. Furthermore, the most suitable foundation option for tower A is 66 square-sectioned displacement jointed pre-cast concrete piles with a width of 350 mm and length of 60 m. These dimensions generate a total concrete volume of 485 m3 for the piles. For tower B, the most suitable foundation is 100 square-sectioned displacement jointed pre-cast concrete piles with a width of 350 mm and length of 55 m. These dimensions generates a total concrete volume of 663 m3 for the piles.