Week 1 studio session activity report: The first session of the semester for constructing environments started with a quiz on introductory topics discussed in the first lecture. Mass structures were introduced as structures that have a purpose of carrying a lot of weight like apartment buildings carrying static load (dead load) and live load (moving load). A diagram was drawn on the board illustrating how loads are transferred with in a building, if a load is located in the centre of the object (beam for e.g.) the load will be transferred along the beam all the way to the ground, which elicits an opposite and equal reaction force explained by Newtons third law “For every action there is an equal and opposite reaction”. The class got divided into three groups of five, and got asked to build the highest tower possible using wooden blocks. The tower had to sustain its static load without the use of any exterior objects to help attach the wooden blocks to each other. An objected was provided by the class tutor that had to enter the tower through two openings one on the bottom floor and one in the middle of the tower. The group took an unusual approach in the construction of this mass building. Mass constructions transfer these loads predominantly by using compression concrete is a great compressor. However, since wooden blocks were used, a ‘Jenga’ approach was chosen for this building. The base of the tower was a square base with 10 horizontal blocks on each of the four sides; gaps were left in between every block in order to widen the tower and hence transfer the load in a way that would reduce the lateral force as the structure increased in height, or so it was hypothesised. As the tower got taller it started moving slightly at the top. It was observed that the four sides did not stay in a straight line and had different widths which really decreased its ability to resist lateral forces and as a result broke apart at knee height (around 60cm).
2D view of the tower with 10 blocks on each side of the square base
Draft sketch of the wooden block structure using a ‘Jenga’ design from a 3D perspective
Week 2 studio session activity report: In this week’s studio session the quiz revised force distribution, materials, and construction systems and processes. There are many important components in the built environment some require certain building criteria such as strong, skeletal, surface membrane or hybrid. It can be argued that a skeletal system is the most used and effective system in construction, it has a great way of transferring loads; it uses a frame system which gives it a nice looking display. What defines a building is not just the construction system used but rather the enclosure, structural, and service systems that are all combined to form a structure. The class discussed how doors and windows qualify as an enclosure system as it is not part of the structural system and are a matter of personal comfort, opening and closing windows with comparison to walls that cannot be moved as they are a part of a structural system. In the same groups as the previous studio session a frame construction was built. 20 long pieces of cut balsa wood were used with the help of PVA glue and tape to help stick the pieces of balsa wood together. With structural loads and load distribution in mind a square design with diagonal bracing was adopted as seen in the sketches and pictures. Measurements such as the height and width of the balsa wood were recorded in order to find out the dimensions of the tower. Two 20cm pieces of balsa wood were used for width and height to give extra support and a 28cm (20 ) diagonal in a ‘Z’ shape to divide the load and produce a steady and sturdy structure. Due to time constraints the tower only went up to around 70cm, but had a strong base which resulted in an evenly distributed load. For the deconstruction process the balsa wood was cut with scissors one side at a time to see when the tower would collapse starting with the diagonal bracing all the way to the 2 diagonal pieces at the base, which is when the structure dissembled.
First stage of construction PVA glue used to stick the Balsa wood together Process of bracing and reinforcing the structure
The drafting and calculation sketches after measuring balsa wood, calculations of width height and diagonal bracing
The highest stage of tower construction approx 70cm
Deconstruction stage to test when the tower fails
Week 1 E-learning and Reading module Knowledge Map:
Week 2 E-learning and Reading module and lecture Knowledge Map
Week 1 Glossary: Load path: A path that forces take as they distribute through to the foundation of the structure
Masonary: Building built with a mason, stone, brick/clay and concrete Compression: Action of pushing the material from each side hence shortening it
Reaction Force: Newton’s thrid law “For every action there is an equal and opposite reaction” meaning that the ground will result in an equal and opposite force as the beam transferring the load to the ground
Point Load: Specific local load in a structure Beam: A long, durable timber or metal piece used in construction e.g. roof
Week 2 Glossary: Structural Joint: When 2 pieces of material (e.g. wood, metal) are joint together physcially Stability: Being balanced by gravity from all sides and has the ability to sustain its own weight (Dead load) and possibly a moving load (Live load) Tension: Stretching an object by pulling it away from each side
Concrete is good under compression
Pre tensed steel rods help distributing the load and withstand larger forces
Frame: A building technique involving vertical and structural members e.g. skyscrapers use bracing for more stability by undergoing tension Bracing:Material that holds 2 parts of the structure together usually placed diagonally, its under tension and distributes the load more effieciently
Coloumn: A long and sturdy supporting pillar usually under compression
References: Francis D.K. Ching, 2008, Building Construction Illustrated, 4th Edition, John Wiley & Sons, 20/3/2014
https://app.lms.unimelb.edu.au/bbcswebdav/courses/ENVS10003_2014_SM1/WEEK%2001 /CHING_chapter02.pdf Photographs: Yazid Hussein, 14/3/2014