Lecture 6: Precedents in Single Story Framed Structures

Flashcards about precedents in single-story framed structures, including trusses, beams, and material considerations.

What is a truss in structural engineering?

A structural system consisting of different components, typically a top chord, a bottom chord, and members in between, used for large span structures.

What happens to a simply supported beam under load?

It deflects, resulting in compression at the top and tension at the bottom.

What is the neutral axis in a beam?

The point where there is neither tension nor compression; the beam is not working very hard at this point.

Why are hollow sections efficient in structural design?

They remove material from the center where it's not needed, reducing weight and increasing efficiency.

What is the principle behind an I-beam's efficiency?

Having one central spine, which optimally distributes material to resist bending forces, making it structurally efficient.

Why are trusses used for large spans instead of single beams?

As spans increase, beam size and self-weight become critical; trusses offer a more efficient solution by distributing forces.

What is the Lisbon Expo's structural system?

A trust portal frame structure with pinned joints at the base and a rigid connection at the top.

What is the depth-to-spine ratio of the Lisbon Expo's structural section?

Approximately one-seventh of the span.

What was the Sainsbury Centre designed to be originally?

2 or 3 buildings, but it ends up as one

What is the main structural feature of the Sainsbury Centre?

A large truss that allows for services to be integrated within it, creating a flexible space.

What was the initial structural scheme for the Sainsbury Centre?

A conventional portal frame with columns, large beams, and tensile members.

What problem did the architects face with the initial Sainsbury Centre design?

How to deal with utilitarian spaces like toilets and storerooms without disrupting the pure space.

What solution was adopted for the Sainsbury Centre's structural issues?

A large structural zone (truss) to house services, with the external wall hung from cantilevered trusses.

What is a prismatic truss?

A triangular truss in section, forming both columns and roof members.

How does the Sainsbury Centre achieve stability?

Through cantilevered fixed end columns and a pinned joint at the top.

What are the external panels of the Sainsbury Centre made of?

Anodised aluminium with a core of foamed insulation.

Neoprene gaskets were borrowed from which industry?

Automotive Industry

How is lateral stability achieved in the Sainsbury Centre's end wall?

Braced bays

What design challenge did the Menil Gallery need to overcome?

Controlling daylight to avoid damage to artwork.

What are the 'leaves' at the Menil Gallery and what do they do?

Louvers that control light entering the space, providing indirect natural light.

What are the leaves at the Menil Gallery made of?

Ferro cement

How does the Menil Gallery achieve the light effect in the gallery?

By using the leaves and a simple glazed panel on top the filter natural daylight.

What structural system is used to support the 'Louvers' at the Menil Gallery?

Trusses

What is structure of the Menil Gallery?

A simple frame with four pin joints

What is the roof of the Menil Gallery made from?

Sheets of glass