Design and construction of an all glass cube for the Raaks project in Haarlem (NL)

On a square in the old city center of Haarlem (NL) on top of an underground carpark garage a glass entrance building was designed by architect Kraayvanger Urbis.ABT/ Rob Nijsse developed the all glass structure for this spectacular building. Thefact that the stability was provided by the roof in combination with the four walls ofthe project makes it something special. Also the application of full glass rods in thestructure of the roof is an innovation in the world of making glass structures

Concrete shell structures revisited : introducing a new and 'low-tech' construction method using vacuumatics formwork

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Discrete Element Modelling of VACUUMATICS

Vacuumatics consist of independent particles inside an airtight enclosed membrane, that are prestressed due to a difference in (air) pressure. Analytical and numerical research of vacuum prestressing has illustrated that the effective prestressing forces can be divided into two interrelated prestressing components. Due to the granular characteristics of Vacuumatics, the material behaviour can be modelled by means of the Discrete Element Method (DEM). The individual prestressing components acting on the edge particles of vacuumatic structures can be simulated by means of a specialised Atmospheric Pressure Model in HADES (by Habanera). Analytically defined equations form the basic input in this simulation process. These simulations enable us to analyse (visually as well as numerically) the prestressing forces, but also the contact forces and the displacements of each particle due to this vacuum prestressing. Furthermore, bending phenomena of beam-shaped Vacuumatics can be analysed in detail, providing us with insight to describe and predict the structural properties of any type of vacuumatic structure

VACUUMATICS; Systematic Flexural Rigidity Analysis

The structural integrity of vacuumatics relies on the principle of prestressing unbound particles inside an enclosed membrane. By introducing a negative pressure (partial vacuum) inside this airtight flexible enclosure, the membrane is tightly wrapped around the outer particles, hence effectively bonding the particle filling to create (adaptable) load-bearing structures. Analytical and numerical studies on the fundamental prestress derivation of vacuumatically prestressed structures have shown that the effective prestressing forces between the particles largely depend, apart from the differential in (air) pressure differential, on the elastic properties of the skin material. The flexural rigidity of vacuumatics is mainly determined by the material properties of the particles and membrane used. Variations in elasticity of the skin and particle filling, and with this the shape, size, compressiveness, roughness, and packing density of the individual particles, highly influence the structural behaviour of vacuumatic structures. In order to explore the influence of different particle and skin characteristics (or parameters) on the flexural rigidity, experimental research has been carried out by means of four point bending tests. Different types of particles were used to discover behavioural trends dependent on the parameters varied. The results of this study provide an enhanced understanding of the true overall structural response of vacuumatics. By systematically elaborating the different parameters, we are able to determine what specific material properties are desired to design the ‘most efficient’ vacuumatic structure for every application

Segmented Barrel-Vaulted Glass Roof

A structural system for segmented barrel-vaulted glass roofs has been developed,aiming at maximum transparency due to structural optimization. This has led to astructural system with small connections, integrated into the glass, as well as clear,transparent joints. Finite element analysis and a full-scale test has been performed,showing PVB-laminated glass, 101010.4, could be sufficient to create spans up to20 meters with slightly prestressed cables measuring just 3 mm in diameter

Beyond forcing scenarios: predicting climate change through response operators in a coupled general circulation model

Global Climate Models are key tools for predicting the future response of the climate system to a variety of natural and anthropogenic forcings. Here we show how to use statistical mechanics to construct operators able to flexibly predict climate change for a variety of climatic variables of interest. We perform our study on a fully coupled model - MPI-ESM v.1.2 - and for the first time we prove the effectiveness of response theory in predicting future climate response to CO2 increase on a vast range of temporal scales, from inter-annual to centennial, and for very diverse climatic quantities. We investigate within a unified perspective the transient climate response and the equilibrium climate sensitivity and assess the role of fast and slow processes. The prediction of the ocean heat uptake highlights the very slow relaxation to a newly established steady state. The change in the Atlantic Meridional Overturning Circulation (AMOC) and of the Antarctic Circumpolar Current (ACC) is accurately predicted. The AMOC strength is initially reduced and then undergoes a slow and only partial recovery. The ACC strength initially increases as a result of changes in the wind stress, then undergoes a slowdown, followed by a recovery leading to a overshoot with respect to the initial value. Finally, we are able to predict accurately the temperature change in the Northern Atlantic

Introduction to the special issue on the statistical mechanics of climate

We introduce the special issue on the Statistical Mechanics of Climate by presenting an informal discussion of some theoretical aspects of climate dynamics that make it a topic of great interest for mathematicians and theoretical physicists. In particular, we briefly discuss its nonequilibrium and multiscale properties, the relationship between natural climate variability and climate change, the different regimes of climate response to perturbations, and critical transitions