Structures Structures A structure is an arrangement of

Structures

Structures A structure is an arrangement of parts joined strongly together. Most objects are arrangements of parts, e. g. atoms, crystals, cells Atoms / Cells Crystals

Structures Golden Gate There are many different types of structures in existence Can you name some structures? Eiffel Tower Examples of structures include – Buildings, Bridges, Cranes, Chairs.

Structures What do you think contributes to strength in structures? This picture shows Buildings, a tower crane and scaffolding Tribal Home Factors that contribute to strength in structures. • The strength of the material • The shape of the parts • The method used to join them together • The manner in which they are arranged

Structures There are many very strong structures to be found in nature. How many can you name? Spiders Web Trees

Structures Naturally strong features in useful designs Bee honeycomb Mount Everest Honeycomb floor mat Pyramid Egypt

Structures Grass Naturally occurring structures include: • A grass leaf Shell • A water lily • A palm tree leaf • Sea arch • Car shell Water lily Sea arch Palm tree

Structures Grass leaves have a honeycomb structure which, although very light, are also thick and strong. Grass leaf under a microscope Honeycomb used as a core in sandwiched structures, boards and flooring.

Structures Water lilies have a web-like structure, which grows from the centre to the outside of the Leaf giving it strength. The Eiffel tower’s giant Lily Pad design of the future. Above the view of the underside of a water lily A structure made with parts that extend to meet each other

Structures Palm tree leaves, though light, gain their strength from thin sheets folded into corrugations. Corrugated roofing Palm tree leaf Corrugation used in packaging

Structures Sea Arch. Coastal features, formed by weathering Roman Arch Sea arch Steel arch used to support a roadway

Structures Shells provide shelter, and protect. Thin-shell structures are light weight constructions

Structures Beams come in various shapes and sizes Beam A beam is a strip or section of material used to span a distance

Structures Frames are structures made from sections of materials. The shape which is repeated in the images is the triangle.

Structures A triangle is one of the strongest frame shapes known to man. The implementation of this concept in design is known as triangulation. member Adding one more member makes the frame stable. joint

Structures Wall Tie Strut • • A strut is the part, which has compressive forces acting upon it. A tie is the part of a structure which has tensile forces acting upon it.

Structures Calculating Forces The frame opposite supports a Mass of 60 Kg. Pin A in the sketch is in equilibrium. Calculate the size of the forces acting on members B and C in the frame. In order to calculate the force of the Mass in Newton’s, the Mass must be Multiplied by 9. 81 N, rounded to (10). Therefore force equals 600 N. 300 N 519. 6 N 60 Kg Triangle of Forces diagram. 60 Kg The force at B is calculated as: 600 Cos 60° = (600)(0. 5) = 300 N The force at C is calculated as: 600 Sin 60° = (600)(0. 866) =519. 6 N

Structures Factor of Safety is used to provide a margin of lee-way of flexibility over theoretical capacity of the item in question.