Analytical and numerical load evaluation from excavation shoring on the powerhouse Kirchbichl

Tiroler Wasserkraft AG realized the extension of hydropower plant Kirchbichl located in the Unterinntal built in the 1940s for the first time. The excavation pits were retained by a bored pile wall with jet grouting connections between the piles, supported with up to two bracing horizons. Safety against uplift during construction stage is managed by a deep-set jet grouting plate, which is partially anchored. Due to the dismantling of the bracing during the construction progress a partially load transfer from the bored pile wall on the partly completed concrete construction and the jet grouted plate occurs. This interaction is simulated at the static calculations. The excavation shoring was calculated by using a geotechnical program. The resulting spring supporting forces from geotechnical consideration were used in the finite element model as loads on the new reinforced concrete walls to calculate the necessary reinforcement content during construction sequence. The results from construction sequence were perpetuated at final state of the new powerhouse structure to get the governing reinforcement content. © 2020, Ernst und Sohn. All rights reserved.