The Diagrid System
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Introduction
The term Diagrid is a portmanteau of ‘diagonal grid’ and is a technique typically used for constructing large steel buildings by creating external triangular structures with horizontal support rings. The diagonal members intersect each other and the horizontal rings at a single node. The members combine to create an element similar to a moment frame. In a Diagrid structure, gravity and lateral loads are resisted by all of the members, creating efficiency and large amounts of structural redundancy. A Diagrid structure effectively creates a rigid shell which can be thought of as a very thin, deep beam.
Some noteworthy examples of buildings that have the Diagrid incorporated are The Swiss Re building in London known as The Gherkin, The Hearst Tower in New York, The CCTV Headquarters in Beijing, The West tower in Guangzhou, The Capital Gate in Abu Dhabi.
The Diagrid systems are the evolution of braced tube structures, since the perimeter configuration still holds for preserving the maximum bending resistance and rigidity, while, with respect to the braced tube, the mega-diagonal members are diffusely spread over the facade, giving rise to closely spaced diagonal elements and allowing for the complete elimination of the conventional vertical columns. Therefore the diagonal members in Diagrid structures act both as inclined columns and as bracing elements, and carry gravity loads as well as lateral forces, due to their triangulated configuration, mainly internal axial forces arise in the members, thus minimising the shear effects. To begin with the behaviour of basic Diagrid module is discussed, followed by construction process. Then the advantages and disadvantages of Diagrids are listed.
The History of the Diagrid
Although the Diagrid is now seen as a modern new technology in the construction industry, the Diagrid is not necessarily a new concept. The Diagrid concept may not have been primarily related to buildings, the ideas and structural inherent
Introduction
The term Diagrid is a portmanteau of ‘diagonal grid’ and is a technique typically used for constructing large steel buildings by creating external triangular structures with horizontal support rings. The diagonal members intersect each other and the horizontal rings at a single node. The members combine to create an element similar to a moment frame. In a Diagrid structure, gravity and lateral loads are resisted by all of the members, creating efficiency and large amounts of structural redundancy. A Diagrid structure effectively creates a rigid shell which can be thought of as a very thin, deep beam.
Some noteworthy examples of buildings that have the Diagrid incorporated are The Swiss Re building in London known as The Gherkin, The Hearst Tower in New York, The CCTV Headquarters in Beijing, The West tower in Guangzhou, The Capital Gate in Abu Dhabi.
The Diagrid systems are the evolution of braced tube structures, since the perimeter configuration still holds for preserving the maximum bending resistance and rigidity, while, with respect to the braced tube, the mega-diagonal members are diffusely spread over the facade, giving rise to closely spaced diagonal elements and allowing for the complete elimination of the conventional vertical columns. Therefore the diagonal members in Diagrid structures act both as inclined columns and as bracing elements, and carry gravity loads as well as lateral forces, due to their triangulated configuration, mainly internal axial forces arise in the members, thus minimising the shear effects. To begin with the behaviour of basic Diagrid module is discussed, followed by construction process. Then the advantages and disadvantages of Diagrids are listed.
The History of the Diagrid
Although the Diagrid is now seen as a modern new technology in the construction industry, the Diagrid is not necessarily a new concept. The Diagrid concept may not have been primarily related to buildings, the ideas and structural inherent