CONSTRUCTION ENVIRONMENTS- REFLECTIVE JOURNAL FOR WEEK 1 The first week of classes for construction environments was more of familiarizing yourself with the subject and the overview of the content throughout the semester. In Wednesday’s lecture, the lecturer introduced us to the subject by giving us brief information on the assignments, how things worked in the subject, what books were necessary to purchase and the introduced us to the tutors who informed the students about skills we had to bring out in the subject and so on. We were told to prepare for the A01 construction assignments and so I made a list of different families where I had listed about 6-7 objects of different shapes and size. There wasn’t much content delivered in the tutorial the following Friday because it was our very first tutorial and we were given an outline of the assignments coming up and how to go about them. There was an activity to kick start the discussion in the tutorial and I often heard the terms “stability”, “tension”, “center of gravity”, “beams”, “deflect” and “compression” throughout the last two hours of class. The focus of the tutorial was on compression. Compression is defined as1 “a force that tends to shorten or squeeze something, decreasing its volume” and volume defines the space occupied. The activity consisted of students working in pairs of three to build a tower as high as possible by placing an animal in the tower making sure to construct windows and an opening. Initially, the group came up with ideas as how to arrange the tower and in what sequential order so we started to place the wooden blocks in the manner as shown below:
We thought of stacking the wooden blocks like bricks usually used to construct walls and other essential features in a building. We overlapped the wooden blocks at the joints of the blocks in the previous layer to make it stable and once after forming layers of the base, we constructed windows by placing them on the thinner side of the blocks and then interconnecting the windows by overlapping them with blocks placed horizontally on top of them as seen in the picture below: 1
"Compression Science Definition." Compression. N.p., n.d. Web. 06 Aug. 2013. <http://science.yourdictionary.com/compression>.
We repeated the same process until the blocks were stable enough to handle the weight of the windows when placed vertically on top of them. The point of the assignment was to explore the nature and behavior of mass construction which is the use of high dense materials in order to construct a structure.
As seen in the picture above, the roof isnâ&#x20AC;&#x2122;t visible but we collected blocks together and tied them with a rubber band which is layered with more blocks to form a flat roof and then placed many of the bundles as roof which now supports the weight of the two boxes as seen in the picture above. The use of the rubber bands removes the tension created by the weight of the boxes. Moreover, the bundle of blocks were placed vertically giving the structure more depth and hence more stability resulting in high compression as the volume of the structure is more compact. The pictures below
are other towers made by three other groups:
The three photographs above display the work of my classmates. When comparing their structures, it can be assumed that the structures with a flat base as the roof surface will hold up more weight rather than the tower that is built tall which narrows as it reaches top point. It will not be able to hold any weight and when trying to amend the structure, it will collapse as it was tested in class by slowly removing bricks from the tower. A better solution to this particular structure is to build an arch to cover the tower as it only compresses it and is tension free. Each one of us was assigned with a term to look for and I was given “pin-joint”. The first idea that pops in my mind when I hear “joint” is the joint that connects bones. It acts as a mechanical support and carries out the functions related to movement. Pin joint carries out the same roll any joint present in the human body does. Pin joint is defined as 2 “A pin joint is a solid cylinder-shaped device, similar to a bolt, which is used to connect objects at the joint area. This type of joint connection allows each object to rotate at the point of joint connection.” Pin joints are used to connect beams in a braces, in ships to wind the chord back which is used in the spin as well as in objects that rotate around its axis. The past week although being an introductory to construction environments, I found the activity done in the tutorial interactive and exciting because it was all so new to me and I was intrigued by terms my tutor frequently used which I slowly begun to understand as I wrote my reflective journal. I am definitely looking forward to the upcoming lectures and tutorials!
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Holmes, Troy, and W. Everett. WiseGeek. Conjecture, n.d. Web. 06 Aug. 2013. <http://www.wisegeek.com/whatis-a-pin-joint.htm>.
CONSTRUCTING ENVIRONMENTS REFLECTIVE JOURNAL- WEEK 2 This weekâ&#x20AC;&#x2122;s focus was on the referencing of structural systems from natural and manmade systems such as gravity, wind, water and seismic which are lateral forces. A couple of new words unraveled as the lecture proceeded and I found myself to be intrigued by the use of bio-mimicry and bio inspiration which is using nature either as a mimicry or an inspiration, in their literal sense. The example of the skeletal structure of a whale was used to construct the frame of an airplane and a house amidst a jungle was made in shape of a football. The cellular structure of a plant was also used in inspiring the structure of the buildings. The materials, functions, contexts, sustainability are factors brought into light with the construction and structure of the igloo and the teepee which I found particularly interesting. Their structures do vary because igloos use the concept of lattice work where as teepees use cladding. This weekâ&#x20AC;&#x2122;s tutorial was to test the fundamentals of frame. It consisted of a task in which we were provided balsa wood and it had to be cut into forty strips of any length and we had to construct a tower as tall as possible. My group members and I initially sought out to making the base of the tower and as we placed the strips of wood diagonally to form a triangle at the top point by connecting legs to the base of the structure.
Apex of structure
Vertical line through which a line passes through acting as the center of gravity
Base of structure
The diagrammatic representation of the structure is somewhat in the shape of a pyramid where the wooden legs/beams converge at the apex through which the center of gravity acts. Since the balsa wood was cut into thin strips, the material was not strong enough and we had to add extra support to the frame of the structure by adding braces at the edges to make the structure stabilized from collapsing as seen below in the diagram:
The final outcome of our structure was:
There were various factors contributing to the dis-orientation of our tower: 1. 2. 3. 4. 5.
Thickness of the wooden strips Time taken for the glue to dry/ not a strong glue Limited number of sticks Inaccuracy in measuring the distance between one wooden beam from the other Limited time
By triangulating the structure, it is subject to axial tension and compression. Instead of continuing with this structure, we could have had a square base so that the load would be less concentrated but distributed well across the structure. 3This is the concept of plate structures- they function as monolithic structures that disperse applied loads in a multidirectional pattern. This way it behaves as a two way structure which also increases the number of members into which the shear is transferred and reduces the forces in the members. By following this method, the structure would be more stable and have less chance of swaying and finally collapsing if any load is transferred to it. If triangulating it would be a better option, then the measurements have to be taken into consideration such as the distance between one wooden leg to the other or the angle of slant but this would be relatively difficult taking into the consideration the constraints of this task as mentioned in the previous pointers. Below are structures my classmates constructed:
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D.K Ching, F. 2008, "Plate structures" in Building Construction Illustrated, Fourth edn, Wiley, , pp. 2.18.
The structure above on the left is stable because of the spacing between the wooden legs is fairly accurate but then again the structure as a whole is very short contributing to its stability. The group could have made a large triangular base and continued to the apex, narrowing every triangle the bottom legs joined to as the structure gets taller. The structure above on the right is unstable because it is disorientated although it has a great height compared to the other two structures previously discussed about. The problem with this structure was that the spacing in terms of height was too far apart having a concentrated load on the base causing all the tension to be passed down to the legs causing them to slightly bend outwardly. The structure could have been improved by providing extra support by attaching additional strips of wood diagonally across the rectangles as well as include braces. So far, I am enjoying my construction lectures and tutorials and hope to learn more from the upcoming sessions. I am looking forward to the site visit this Friday!
CONSTRUCTING ENVIRONMENTS REFLECTIVE JOURNAL- WEEK 3 The focus of this week was on structural loads and forces where the readings were extremely interesting and easy to grasp on. This week’s lecture was a discussion held on a building pavilion where specific examples of some of the lecturers had worked on- we had a few guests come in who had specific roles in constructing a site and we were introduced to what they had to do and how their roles were all interconnected in order to collaborate as a group. The guests brought in strong notions and important factors required in the process of construction such as using less structure to construct so this could possibly bring out sustainability and how they can incorporate heritage component into the construction and various other factors. The A01 project was indeed time consuming but interesting because only 10 words were allotted to each cell so a lot of thinking had to go in to use appropriate words to describe the structure and the materials of the family of objects chosen. In the tutorial, we had to go on a site visit to four sites where we had to observe and write it down on the worksheets given. It was a little inconvenient because there were many students and I wasn’t able to catch up to the teachers as they were ahead of me and were already explaining the features of the specific sites chosen. We learned different aspects of construction and had to use the knowledge we obtained from the previous lectures and tutorials to real life figures. The readings I found most interesting this week were the basalt blue stone that’s used as a foundation for buildings and is found in plenty in Melbourne and how the lava flow is seen when observed closely on the pavements in Melbourne. Another interesting aspect from the readings was the different types of footings that were available and depended on the bearing capacity of the soil. The glossary term I had for this week was “cross section” which is in its literal meaning, a parallel cut through a site at the right angle. A simple example is cutting a water melon in the middle and you have the cross section. As an example, I used the railway station cross section. Cross sections are used basically to view the spacing and to figure the inner diameters as well as to place the hydraulic system and other necessities. Some of the newly learnt concepts such as reinforcement were seen on site where the type of reinforcement done was using concrete where they put the concrete through a steel mesh on site. The purpose of the steel mesh was to act as a foundation by holding all the cement together. I am looking forward to working on my A02 full size project as it will be something completely new yet exciting!