Learning loop: walls may be enclosure system or structural system of a building ( in some cases both). During the site visit, I noticed the light concrete they use for as a exterior wall is only functioning as the enclosure system while the exterior brick veneer wall at the ground floor has both functions. The sketch on the right shows the structural system of a brick veneer wall. The outside brick veneer is used for athletic view, that the actual load bearing part of this system is the timber stud wall. The gap in-‐between the brick veneer and the timber stud wall is usually used for insulation and water proofing materials. However sometimes it just left empty as air has good thermal mass. Inside stud walls are structural system only. It used widely in timer constructing. The sketch shows different parts of the stud wall: noggins are used for rigidity so that the studs can span; cross bracing are usually made of steel and used for stabilise the studs; plywood sheet bracing functions the same as cross bracing, however, it is not always necessary to have sheet bracing. For example in our visiting site, I noticed that at the top floor stud wall there is no sheet bracing because the load it bears is lighter than ground floor, where stud wall has double sheet and cross bracing. The usage of steel in bracing is because steel is less likely to bend than timber. Except for brick veneer, light concrete is also used for cladding stud wall that both Melbourne school of designing and my visiting site used this material. Sometimes for timber stud wall, it requires steel columns and beams to support the whole structural system as timer is soft and easy to brick. The opening on stud wall increase the span of the stud, therefore it requires heading and double stud around to bear the load at this area. Sketches shows when the force is applied, the use of cross bracing on pin joint frame.
The sketch on the right shows the different failure point when different joints are applied for both long columns. (short columns trend to crushing).
The task of this week is to develop a working understanding of the system of a building through analysis of architecture and constructing documentation. And therefore, we are asked to make a model of structural component of oval pavilion according to it. This is the part of oval pavilion we should build. This is our final outcome of the structure because we were running out of time. The main reason we didn’t finish our structural system is because we struggled to find out the size of the column and beam, which is in the constructing drawings. and also for the length of the beam, we at first tried to measure the length of in architecture drawings but soon found out the scale is based on A2 size while our formate is A3 size. The second struggle is to find the location of steel trusses. The sketch model is on a scale 1:100. The scale of our model is not entirely correct, in terms of the thickness of the structural system. The picture shows the structure system of another group, who built the main building structure behind our pavilion. Although they have roughly finished the structural roof system of the structure, the ratio of all beams and joists were not according to the construction drawing. The constructing drawing shows the type of the columns and beams, also the size of it. the length of all columns should be found in architecture drawing that they provided all measurement in real size. We used pin to connect columns and beams, which later on proved to be a bad decision that the joint between these two structural system should be fixed joint so that all movements are prevented to provide a rigid structure.
To begin with, we looked at horizontal section at roof to have an general idea what we should build for roof. The main structure for roof system is the timber columns and beams. Started with columns, the location and the size of the columns can be found in foundation plan in architecture drawing, because they are site on the footings. In this case, because the footing is supporting a column, it should be pad footing. However, the column is not directly into the foundation but the concrete slab above foundation wall. As the column is load bearing, dose the column extended into the foundation or supported by the load bearing wall of the basement? The detailed information of how these components are interconnected are cycled in the detail section, and these all referred to a drawing number. The detailed drawing shows the size and material use of small components. The working drawing on the
glossary: STUD: is a vertical framing member in a building's wall of smaller cross section than a post. They are a fundamental element in building framing (“stud”, 2014). NOGGIN: A short horizontal wooden beam used to strengthen upright posts in the framework of a wall. It is used for stud span. BUCKLING: when the force is applied on a column or a beam, buckling is the way it bends. The picture shows two different types of buckling. (“hillcross furniture”,2011) LINTEL: can be a load-‐bearing building component, a decorative architectural element, or a combined ornamented structural item. It is often found over portals, doors, windows, and fireplaces (“lintel”, 2014). SEASONED TIMBER: when water percentage in timber is smaller than 15%. Season timber is used for construction.
reference: Hillcross furniture, (2011, January). from: http://www.hillcrossfurniture.co.uk/blog/2011/01/hill-‐cross-‐new-‐office-‐building-‐works-‐ continue/_mg_4182/ Lintel, (2014, September). from: http://en.wikipedia.org/wiki/Lintel_(architecture) Nogging, (2014, September). from: http://www.thefreedictionary.com/nogging Stud, (2014, September). from: http://en.wikipedia.org/wiki/Wall_stud