The Karlsruhe Monster-Highly Flexible Steel Formwork, Operated Under Hyperbaric Conditions: Design and Application of a High-Tech Formwork in a Tapered Tunnel Section

摘要

Connecting two stations of the new Light rail scheme in the heart of Karlsruhe, Germany the Kaiser-Friedrich-Tunnel had to be excavated and finally lined under compressed air conditions. An extreme widening of the tunnel on the last 40 meters made the inner lining works special with regard to both the selection and erection of the formwork as well as the construction of the lining. The nearly 200 ton formwork was erected and operated inside the pressurized tunnel, all works were performed in a 24/7 operation at up to 1.15 bar (17 psi) air pressure. The paper describes the challenges faced in connection with these unusual conditions.