ENVS10003 CONSTRUCTING ENVIRONMENTS
LOGBOOK Victor Lu 613204 Group 21
ENVS10003 CONSTRUCTING ENVIRONMENTS LOGBOOK 613204 VICTOR LU
Knowledge map of weekly eLearning, reading and lecture
WEEK 1 Since this is the first week of new semester, this week’s lecture introduces this subject to us such as subject structure, assignments and so on. The reading involves the basic concept of force and load and also eLearning mentions something about materials selection. In the lecture, we made a trial to use one piece of paper to bear a brick. Some solutions failed and some of them succeed. It will be discussed in following pages. In the studio, we made a towel with medium-density fibre block to investigate load and force of a structure. It also will be discussed in following pages.
|1|
ENVS10003 CONSTRUCTING ENVIRONMENTS LOGBOOK 613204 VICTOR LU
WEEK 1
Activities Report Lecture Activity: Using a piece of paper to make a structure to load a brick. I saw an interesting one which I want to discuss it here. The student cut the A4 paper into two rectangle pieces and rolled them into two hollow columns separately, but it failed. The paper columns were huddled together by the load of brick (Image 1). Without considering the material of the column, first thing should be considered in this case is how those two column support balancing the brick. As shown, the surfaces of columns which touch the brick are
quite small. Therefore, to keep them balance, we have to set the column in the middle line of the rectangle’s shorter side (Image 2). Since the distances from column to both sides of brick are same, the forces from two sides to the column are same as well. Therefore, the brick keeps the balance. The columns transmit the load to the ground towards outside evenly. This system could stand steady in theory.
When paper is folded as a pentacle, this structure will extend towards outside due to the flexibility of paper. The brick presses the structure, then the load goes along with each side of pentacle and down towards ground. Extension of paper counterbalances the compression of pressure and the structure remains balance and succeeds to stand (Image 4).
However, the columns are made of thin paper. This material is not full of the stability and toughness Image 3 For my own project, I design the supporting structure as a pentacle (Image 3).
Image 2 Image 1 Image 4
|2|
ENVS10003 CONSTRUCTING ENVIRONMENTS LOGBOOK 613204 VICTOR LU
Image 1 Studio Activity: Using the MDF blocks to build a tower as high as possible and shelters a toy animal. We divided our structure into three parts: foundation, middle layer and upper layer. We used different strategies to build them. For the foundation (Image 1), we set two rows blocks and circle them into a rectangle. Compared with circle, rectangle can be control easier in the structure aspect when it grows high, because cylinder might deform inward. However, this problem in cube can be found clearly, because we can check whether each side is straight or not facilely. And two-row foundation can resolve upper load into much more small units (Image 5), so that the structure can be built higher.
WEEK 1
Image 2 In the middle layer, we use one-row structure (Image 2), and we laid them down to build. The reason is when it lay down, it touch lower structure with largest surface. The load can be resolved into smaller units when contact surface becomes larger. In addition, it reduces the height of block’s centroid, it makes structure stable. Furthermore, we use three blocks compose one structure unit (Image 4), it makes them compose a triangle structure, geometrically, triangle is the most stable shape.
Image 3
Image 4
In the upper structure, we led the block stand up horizontally. Firstly, it can get higher with same amount of material. Secondly, using less material can reduce the load to foundation. Image 5
|3|
WEEK 1
ENVS10003 CONSTRUCTING ENVIRONMENTS LOGBOOK 613204 VICTOR LU
Glossary 1. Static load: it is assumed to be applied slowly to a structure until it reaches its peak value without fluctuating rapidly. It includes live loads, occupancy loads, impact loads and dead loads. 2. Dead loads: one of the static loads; vertically and slowly applies on structure. 3. Live loads: includes moving equipment, collecting rainfall and snow; vertically downwards to ground and horizontally to reflect the dynamic loads. 4. Occupancy loads: weight of people, furniture and stored of material. 5. Snow loads: weight of snow. It varies with geographic location, site exposure, wind conditions and roof geometry. 6. Rain loads: accumulation of water on the roof. 7. Impact loads: kinetic loads of short duration.
8. Settlement loads: subsidence of a portion of the supporting soil. 9. Ground pressure: horizontal force from soil to vertical structure. 10. Water pressure: hydraulic force exerts on foundation system. 11. Thermal pressure: compressive or tensile stresses developed in a material constrained against thermal expansion on construction. 12. Dynamic loads: suddenly to a structure. Includes wind loads and earthquake. 13. Wind loads: exert by the kinetic energy of a moving mass of air horizontally. Sliding/ uplift/ overturing -negative pressure or suction on sides, leeward surface; normal to windward roof surface which is less than 30 degrees. -positive pressure on windward vertical surface; normal to windward roof surface which is more than 30 degrees.
15. Point load: a point where a bearing or structural weight is intense and transferred to the foundation.① 16. Compression: the force to push something together inwards. 19. Masonry: masonry refers to buiding with units like brick, stone, concrete block etc., usually with mortar as a bonding agent (Ching, 2008:12.06) Reference ①Choice of the Type of Foundation. (n.d.) Retrieved from http://osp.mans.edu.eg/sfoundation/foundtion. htm ② Ching, F. (2008). Building Construction Illustrated (4th ed.). Hoboken: John Wiley & Sons, Inc. ③ Euclid, A. (n.d.). Euclid's Elements. Retrieved from http://aleph0.clarku.edu/~djoyce/java/element s/toc.html
14. Reaction force: a force in the opposite direction to action force.
|4|
ENVS10003 CONSTRUCTING ENVIRONMENTS LOGBOOK 613204 VICTOR LU
Knowledge map of weekly eLearning, reading and lecture
WEEK 2 The reading of this week involves the basic concept of building system, which focuses on building form, building structure and environmental structure. In the lecture, we made a trial to use some straws and a tank to build a structure to load as heavy as it possible. I will discuss it in following pages about load and joint. In the studio, we made a frame with MDF sticks as high as possible. I will discuss it in following pages about structure style and something about structural connection.
|5|
WEEK 2
ENVS10003 CONSTRUCTING ENVIRONMENTS LOGBOOK 613204 VICTOR LU
Activities Report Lecture Activity: Using some straws and a tank to build a structure to load as heavy as it possible. One student joined three straws surrounding the round tank (Image 1) and they were perpendicular downward. That was a good idea. Since three joining points were located on vertexes of inscribed equilateral triangle of round, those straws can take the load evenly due to geometrical feature of equilateral triangle. However, this student made a fatal
Image 1
error which is using only one pin to join the straw with plastic tank. Mathematically, there are numerous lines across a point (Image 2), which means the straw can rotate about the joint in this case. This makes structure unstable. Nevertheless, there is only one line existing across two pints. Therefore, one more pin should be joined in the straw to make it fixed. Another project was similar to first one but the student did not make the straw straight downward (Image 3). The load goes along with straw to ground and the gravity goes down vertically. These two forces forms an intersection angle to make the resultant force go down aslant, which cannot response supportive force from ground directly and evenly. That cannot compose balance structure according to Newton's laws of motion (Image 4).
Image 3
Image 2 Image 4
|6|
ENVS10003 CONSTRUCTING ENVIRONMENTS LOGBOOK 613204 VICTOR LU
Studio Activity: Making a frame with MDF sticks as high as possible. Our group decided to use triangle as the basic frame factor to build the tower (Image 1 & 2). Mathematically, triangle has stability because intersection angles between three sides are unchangeable if the length of three sides never changes.
Image 1
WEEK 2 The tower was design as a triangular pyramid. We made different size triangle frames to fix three vertical columns (Image 3). Meanwhile, we resolved the side face into small triangle by adding some beams (Image 4). This structure reduces the load on the main columns and leads them reach to the ground evenly.
Image 2
Image 3
As original designing, three main columns will increases until get together in one point. On that time, the whole frame becomes a closed structure. That is fixed and stable because each stick in the structure can get at least other two sticks’ supporting. That resolves the tension and compression force.
Image 4
|7|
WEEK 2
ENVS10003 CONSTRUCTING ENVIRONMENTS LOGBOOK 613204 VICTOR LU
For the joint of the each sticks, we had two methods: one is sticking them with superglue; another one is bind them with masking tape. These two methods can provide the pin joint for our structure, but in terms of material of this case, masking tape survived. Since the stick is about 0.5cm width, the contact surface between two sticks is quite tiny and narrow. The superglue only sticks to MDF stick a little. The adhesive force is not enough against the gravity and the tension which caused by three vertical columns.
Image 1
Therefore, the stick might fall down in practice. In fact, it did happen (Image 1). Instead of superglue, we used the making tape to blind the sticks together (Image 2 &3). The tape provides a compression to sticks from outside. It increases the static friction between two surfaces against gravity and makes the system stable. Image 4 is the final project which is not complete due to time over.
Image 2
Image 3
Image 4
|8|
WEEK 2
ENVS10003 CONSTRUCTING ENVIRONMENTS LOGBOOK 613204 VICTOR LU
Glossary 1. Structural joint: a connection point where two separate structure come together.
building above the foundation.
2. Frame: a system to support the whole structure.
12. Enclosure system: roof, exteriorwalls, windows, doors. It prevents people from inclement weather, unexpected moisture, heat, air flow and noise.
3. Stability: an ability to stay stably. 4. Tension: an inner outwards force of a structure and material. 5. Bracing: a structure to support itself to stand stably. 6. Column: is rigid, relatively slender structural members designed primarily to support axial compressive loads applied to the ends of the members (Ching, 2008:2.13).
11.Substurcture: foundation of a building
13. Mechanical system: essential services to building, which includes water supply, sewage disposal, ventilating, electricity, inner transportation, fire-fighting and recycling.
Reference Newton, C. (2014) Weekly Guide of ENVS 10003, Melbouren, University of Melbourne. Ching, F. (2008). Building Construction Illustrated (4th ed.). Hoboken: John Wiley & Sons, Inc. Euclid, A. (n.d.). Euclid's Elements. Retrieved from http://aleph0.clarku.edu/~djoyce/java/element s/toc.html Halliday, D., Robert, R. (2005). Fundamental of Physics (7th ed.). USA: John Wiley and Sons, Inc..
7. ESD: environmental sustainable design 8. MDF: middle density fibre 9. Structural system: support and transmit applied gravity and lateral loads safely. 10. Superstructure: vertical extension of a
|9|