The central subject of the thesis is prestressed cable nets. The report is divided into two
fundamental segments. The first one focuses on the theoretical essentials of lightweight tensile
structures (prestressed membranes and cable nets). It explores how they work by explaining
the important principle of double curvature (anticlastic surfaces) and the concept of Gaussian
curvature for classification of curved surfaces. The form-finding design phase is of great
importance. Three types of form-finding are mathematically described (dynamic relaxation,
transient stiffness method and force density method). Software Rhinoceros with plugins
Grasshopper and Kangaroo is used in a simple form-finding example of a hyperboloid cable
net. Lastly, the engineering office schlaich bergermann partner from Stuttgart, where the
author has finished a one-year internship, is presented.
The second segment contains the project of a prestressed cable net facade, enveloping a hot
water storage cylinder. The project's designation is Energie- und Zukunftsspeicher Heidelberg
(eng. Energy storage tank of the future, Heidelberg). The author has participated in the
project's feasibility studies phase and in the initial structural design of the cable net. The
structural system is described (the steel crown on top, the helix beam, spiraling around the
storage tank, and the cable net facade, spanning between the crown and the ground). The
form-finding phase, load cases and load combinations are presented. Certain specialties
concerning the design of such structures are considered and described – cable creep, cable
net deformations, minimising the number of slack cables, etc. Lastly, a few details are
presented (interface between the cables and the concrete, cable clamps, facade panels).
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