#lightandstructure

Bricks on Sticks Report 

Module: Light and Structure

Module: Light and Structure

Week 4 - Materials 

3 things can control: Forces, Material, Shapes

Different geometry means different internal forces: 

Definitions:

Stiffness: Extent resists deformation in response to an applied force

Brittle: Easy to snap

Ductile: Can be drawn into wires

Tough: Resists scratching

Elasticity: Returns to original shape when deformed

Plasticity: Remains in deformed shape

Considering two structural elements (objects), differentiate properties of MATERIAL and GEOMETRY:

Hard Gums vs. strawberry laces - materially similar, geometrically different

“Homogeneous” Material: consistent all the way through

“ Composite” Material: different materials and qualities

Structural materials:

Cost

Availability 

Weight

Electrical/ Thermal conductivity

Thermal expansivity

Durability

Embodied CO2 - (CO2/energy consumed in producing material) 

Eco-toxicity - (extent material damaging environment)

Hooke’s Law: F=-kX

Strain (visible): ∑= Δ L/original L

Stress (invisible):  σ=F/A (cross-sectional area)

Young’s Modulus: E= Δσ/ Δ∑  

Measures stiffness of material 

Removes affect of geometry

Stiffer materials have steeper gradient (higher E)

Yield point: elastic to plastic

“strength quantified”

Concrete - weak in tension, ok in compression (reinforce with steel at points of tension ie. bottom of beam) (E sudden decrease after yield)

Labradorit IV / Labradorite IV

Labradorit I / Labradorite I

Labradorit II / Labradorite II

Labradorit III / Labradorite III

Mechový achát V / Moss Agate V

Bricks on Sticks Design Development

Module: Light and Structure

I focused on developing my arched truss design. The arching would focus the material in the centre of the span to resist the main force of the load. To connect the parallel planes I initially considered cross bracing, however I reflected on the success of the pyramid truss formation we had made in the seminar and developed the structure into a series of connected pyramids. The pyramids were particularly effective at redistributing the load yet still be efficient material usage. 

To create a platform for the bricks to sit upon I needed to adapt the structure to have some members parallel to the base of the brick in addition to the pyramid points. I felt that the pyramid forms would be more efficient in redistributing the load so I alternated the structures design between pyramids and triangular prisms. Due to the prisms’ square faces they would require further cross-bracing (and thus more material) to triangulate the face. 

I experimented with the proposed materials, sticks and floss, which I decided to use for the ties and joints due to its tensile strength. However the floss did pose potentially problematic as the surface of the material made it susceptible to slipping. I will compensate for this with a extra material to avoid the knots coming undone. This mostly posed a problem on the joints where lots of connections were being made as it became floss-on-floss for many of the later added components.