Monday, July 13, 2009

Focus on the Continued Research

I mentioned in the report a number of ideas for possible proposals. For this particular research subject, as described in the previously posted abstract, my interest goes out to one main directions:

"IDEA: If a column free dome is the starting point, we could divide the dome structure in two shells, one resisting the wind loads, and one taking the deadweight of the structure. We could design the “deadweight shell” by distributing points onto the dome shape, and connect the points applying a Voronoi algorithm, in order to get a framework as light as possible, while at the same time being one integrated entity. The wind-shell could be constructed out of a frame following the stress trajectories due to wind loads (one main direction). The one shell should be connected to the other in a way, which is parametrically predefined."

To discuss this a bit further, I want to comment that, wind load is a tricky load case to use as a shape giver. Since it moves around and the force flow caused by the wind on the structure, very much depends on the shape of the structure itselves. To use this principle, we should at least stay to one type of shape of the structure.

Let's assume that we use a dome structure as a model. Based on the adaptive qualities of rads to their loadcases, we could consider to optimize the dome to one main wind direction. And make the dome able to rotate towards the wind direction. Other wise, the structure would collapse, as soon as the wind changes its direction. An other solution could be to over-dimension the structure of the dome in order to make it strong enough to stand wind form all directions, but in this case,this is not our aim, since we want to create a light structure which is as much optimized as possible to its surroundings.

The issue of two cooperating shells: In radiolarians we see that they have to deal with 2 kinds of load cases in general: 1) the distibuted pressure of the water surrounding them, and 2)Impact loads caused my predators or other objects in their environment. This way of dealing with both different types of forces, made them able to develop efficiently. The fine tesselation of their shells withstand the evenly distibuted pressure of the water. While the Impact forces are counter acted by the arm of spines connected to the shells.

If we want to translate this principle to a dome shaped structure, we first have to define our load case. The distributed loading acting on a building is it's selfweight, magnified by gravity. The impact force encountered by a building structure is wind force, although its partly distibuted.

The big question is: How can we integrate this into one structure?

Impact forces and distributed loads acting on radiolarian shell

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