Redundancy tests on glass fins

Since 2010, Octatube has adopted glass fins as structural components in at least 20 different projects, both in facades and roofs (the van Gogh Museum, the Tottenham Experience, Canal House Amsterdam are some relevant examples). Glass is widely known as a fragile material and it usually breaks in a brittle fashion, whereas a metal like steel typically fails plastically. The post-breakage behavior of glass beams is not easy to predict, therefore Octatube performed a range of tests on different glass fins varying the test setup. All tests were performed in house, at Octatube’s factory/test area in Delft, the Netherlands. In this paper two case studies are discussed. For the brand-new Spartherm Headquarters in Melle (Germany) laminated glass fins are adopted to support large insulated glazing units. Due to the round shape of the building the glass fins spanning for a maximum of 5,3 meters, are also curved on one side. The glass fins were tested both in un-cracked and cracked conditions to assess the overall safety of the design. For the refurbishment of the National Gallery of Ireland in Dublin, a new glass roof, over the old Sculpture Courtyard, was designed by Heneghan Peng Architects. With glass beams up to 8,3 m, and 3x10mm fully tempered PVB laminated panes were adopted. In cooperation with T/E/S/S engineering, the second support system was designed for post breakage behavior. In case of total failure of a glass fin, the safety was is ensured by catenary action in combination with a stiff frame of glass beam. This was tested in a true size, 6,0 meter, mock up. The residual capacity in the glass beam is ensured provided that the global structural system and detailing are carefully designed

Automatisering van de berekening van de kosten voor benodigde energie bij teelt in de kas

Beschrijving van de gehanteerde formules en rekenvolgorde van een methode die in een computerprogramma is vertaald. Ter illustratie wordt een berekening van een teelt van lelie cv. Enchantment met assimilatiebelichting, waarvoor elektriciteit wordt geleverd door een total-energy-installatie, volledig uitgewerkt weergegeve

Restoring Hi-Tech Architecture

In this paper we will discuss a challenging, iconic, heritage, refurbishment project – Channel 4’s headquarters building located in London, England. The building was originally designed by Richard Rogers and Partners in collaboration with Arup, RFR and was executed in 1994 by Eiffel under a sub-contract package with Permasteelisa. We will methodically outline the procedures that were followed to assess and restore this ageing, iconic cable net façade where, in an almost unprecedented way, the face glass is used structurally to support the dead load of the panels below to create a chain of suspended glass panes. After approximately 25 years of service Arup was called back to provide advice to the client following a glass breakage incident.  This triggered a detailed condition survey which concluded that a project refurbishment was overdue.  Arup then provided further studies to inform strategic options as to how to best refurbish the façade.  This advice led to the appointment of Octatube to provide Pre-Construction Services Agreement (PCSA) support to assist the façade appraisal and to carry out design, material testing, calculation and to provide critical construction advice, and then lead to Ocatatube’s appointment to fully refurbish the iconic façade

Efficient simulation of periodically forced reactors with radial gradients

The aim of this paper is to present a limited memory iterative method, called the Broyden Rank Reduction method, to simulate periodically forced processes in plug-flow reactors with radial gradients taken into account. The simulation of periodically forced processes in plug-flow reactors leads to the development of partial differential equations that are normally solved in time using dynamical simulation. Depending on the convergence properties of the system at hand, the number of cycles that needs to be computed up to a cyclic steady state is reached can be large. Therefore direct iterative methods are essential in order to capture the long time dynamics of such systems. In order to overcome severe memory constraints many authors have reverted to pseudo-homogeneous 1D models and to coarse grid discretization, which renders such models inadequate or inaccurate. The results that we present show that the long time dynamics actually depends on the radius of the reactor and, hence, the full 2D model is essential in order to simulate periodically forced processes in plug-flow reactors accurately