Logbook Yan Zhang (Arthur) 657337 Tute 20
Week 1 - Week 2
Before we actually started designing the towerâ€™s structure, I took a quick glimpse at several wellknown precedents.
I then drew some sketches showing the basic structure of mentioned towers, and after analysis we found that it seems like modern towers pretty much fa-vour lattice frame work and the basic geometric shape composing the tower is usually triangle. Maybe thatâ€™s because a triangle is the most stable geometric shape as we
Due to the relatively light weight of the material, as early as we were trying to build it, the air flow, which can be regarded as a live load, made it quite hard to attach two glued beam to a third one, so that one of us had to hold and stabilise the joint with hand.
Balsa woodâ€™s provided for us as material. Itâ€™s not very rigid, a lit bit fragile, , can easily buckle, due to low stiffness and strength. So the best option is this case is to start off using the strongest figure, which is triangle. Conceptual model (not realised in the tute and its load paths)
Picture by Stella Mardani
When we began to build the second level of it, the dead load of the upper timber material immediately imposed upon the lower structure. To counter the deflection we use quick setting glue to strengthen the joints and some deflec-tion occurred when we were doing that. Then we repeated the attempts sev-eral times before the whole structure reached
To further distribute the dead loads of structure and possible live loads, we used coplanar and horizontal braces to consolidate the structure at the floor of the second level, which is half way of the height.
Another problem we encountered was that the dead load beame unaffordable for the base as the tower got higher and it actually fell apart. I suggested we might as well use interlock to reinforce the joints again and it did work.
An ancient bracket in East Asia showing how wooden components interlock.
The way we stabilise it was to whittle one stick and in the meanwhile dig a hollow in the other. Glue is applied around the edge of the hollow.
Notes WEEK1 -->
Notes WEEK2 -->
Published on Mar 22, 2014