Design and reliability evaluation of a glass flood defence

Abstract

Typical for the Dutch landscape are the many polders, which are situated below sea level and below waters directly surrounding the polders. A visual separation between land and water is caused by the flood defences that protect the polders from flooding. In 2005, artist Paul Izeboud came with the idea to make a transparent flood defence, thereby making it possible to experience land and water simultaneously, without standing on top of the dike. In 2011, Eduard Böthlingk worked out this idea in an architectural design of ‘The glass dike’. Böthlingk is planning to realize the glass dike inside a regional flood defence that protects the Duifpolder (in the province of South-Holland) from flooding. Based on the architectural design, an engineering design of the glass dike is made in this thesis. This design should satisfy reliability requirements from the Flood Safety Standard. For the regional flood defence that is surrounding the Duifpolder, this safety standard prescribes a design water level with an exceedance probability of 1 in 100 years. The glass dike should be able to safely withstand this water level. Apart from the Flood Safety Standard, reliability requirements that follow from the Eurocode should be satisfied as well. For conventional parts of the structure (foundation, concrete elements, etcetera), design checks were performed with a semi-probabilistic method. For this, partial factors from Eurocode Reliability Class 2 were applied. For the glass elements, a full probabilistic method was applied to compute the failure probability due to overloading. Furthermore, threats to the glass were identified. The most important threats are impact due to a boat collision, fire and explosions. Measures to prevent these incidents and/or to reduce consequences were proposed. Glass is an unpredictable material with respect to its structural behaviour. Its strength is still subject of many researches. It is recommended to also investigate its resistance against fire. Although glass is a vulnerable structural material, it was found that, in general, realization of a glass flood defence is technically feasible.