The Effect Of Outrigger Truss On Composite High Rise Buildings By Simplified Method

Steel frame structures are made as the name suggest from steel, the material is strong and flexible. When weight is added it bends without cracking. Another characteristic of steel is that its plasticity or ductility, meaning that when force is added it won’t crack however it will lose shape therefore giving warning for people to evacuate the building. A disadvantage of steel is that is loses strength when subject to fire. Studies have shown that it can loose up- to half its strength when subject to fire, therefore making it imperative to cover the steel with boards or spray on.

The part of the roof that supports the walls of the house and sustains the weight of the frame is the truss. The presence of the truss is what prevents walls from bending. It is very important for all buildings but particularly multi storey buildings or houses to have a very strong and durable roof skeleton or truss.

Throughout history we can see that housing has followed certain trends. These trends are most heavily influenced by the technology available to the public at that time. As can be seen throughout history, living conditions in general have improved, as there are more access to resources and building technologies. Although the world we live in has changed greatly, the basic type of shelter needed for everyday life and the resources needed to construct them has changed very little. This is why we can see a lot of parallels between the ways people live throughout history. However, the biggest change is in the way we construct buildings and especially housing. History has taught us that as time goes by, technology increases, making it easier for us to build structures. For example the Egyptians relied solely on Adobe (sun dried mud bricks) and slave labor for construction. Then came the development of hydraulic lime mortar, the Treadwell cranes (which is a wooden, human powered hoisting and lowering device) as well as the start of domes and arches, as structural components in architecture. Followed by the Middle Ages, which saw a huge emphasis on the construction of massive public buildings such as Cathedrals, Churches, Fortifications

The purpose of this report is to introduce the roof truss that I had designed for the project of design studio 1 which is personal space. I have included the following content for the design: characteristics, cons and pros, sketch and label, and cross section of the design. The roof truss that I had design for the personal space building is king post truss (also known as crown post truss). According to online dictionary, the definition of king post is a structural member running vertically between the apex and base of triangular roof

Truss roof’s method are used with both gable and hip roof and are prefabricated by making triangular forms reinforced by several other planks of wood. They are now used over 75 percent of new home construction and there are also cheaper than conventional

the scale and height of proposed buildings is compatible with the character of the locality, and

As an innovative and efficient structural system, the outrigger system comprises a central core, including either braced frames or shear walls, with horizontal ‘‘outrigger’’ trusses or girders connecting the core to the external columns. Furthermore, in most cases, the external columns are interconnected by exterior belt girder. If the building is subjected to the horizontal loading, the rotation of the core is prevented by the column-restrained outriggers. The outriggers and belt girder should be at least one and often two stories deep to realize adequate stiffness. Thus, they are generally positioned at plant levels to reduce the obstruction they create.

When driving into a city the horizon is always very awe dropping, highlighted by the various high-rises and skyscrapers that outline the city. The Council on Tall Buildings and Urban Habitat (CTBUH) defines a high-rise building as “a building whose height of over 75 feet creates different conditions in the design, construction, and use than those that exist in common buildings of a certain region and period” (CTBUH). High-rise buildings exist in our civilization, mostly in our large cities, to save space and money. “In large urban areas, cost of construction is 87% cheaper to build up than it is to build outward” (NFPA). In urban areas, land space is limited and very valuable. Skyscrapers can house different purposes consisting of; office space, apartment living, and even entertainment purposes. These types of buildings present several unique challenges not found in traditional low-rise buildings; longer egress times and distance, evacuation strategies, fire department accessibility, smoke movement and fire control. Dr. W. Z. Black is a member of the American Society of Fire Safety and Engineers; He stated, “During an emergency, the multiple floors of a high-rise building require great numbers of persons to travel great vertical distances on stairs in order to evacuate the building” (Black). Based on the numerous issues and concerns found within high-rise buildings, it is evident that fire safety is a major problem.

When we walk through the halls of a modern office building, unless there are underlying psychological issues, few wonder if today will be the day the building collapses. Few people question if the floor is strong enough for their weight, if the wind will blow over the structure, or if there are enough exits to safely get out of the structure in an emergency. Why is it that all over the world, for the most part, buildings are relatively similar? Why is it that people don’t question the structural intergrity of a facility every time they enter? The answer is standardized construction through the incorporation of Building Codes. Over thousands of years the process of regulating construction has become so engrained into society that few today question the integrity of their office building, highways, or homes.

Prestressed concrete is a procedure where the loadbearing strength of concrete is increased significantly. Basically, it is a concrete in which suitable internal stresses of suitable magnitude and distribution are introduced so that the stresses caused from the external loads are neutralized to an anticipated degree. The benefit of prestressed concrete is that it can be used for construction of large spans (more than 30m) with slender members, even on encountering with heavy loads. As enhanced materials (controlled concrete and high tension steel) are being used, the modulus of elasticity is higher and ultimate creep strain is smaller resulting in the reduction of cross section of the structural components. Due to smaller dimensions, there is reduction in loads causing smaller deflections and lead to saving cost in the supporting members and foundations.

This report aims to examine the advantages and shortcomings of four different types of bridge, namely the truss, suspension, beam, and cantilever bridges. Secondly, it evaluates three forces that act upon these bridges ㅡ compression, tension, and shear ㅡ and how each kind of bridge handles the forces. Lastly, it includes a explanation of the Tacoma Bridge incident and a description of the author’s bridge.

Climate change is expected to negatively affect the future of most developing countries, increasing the pressure on available resources that are associated with urbanisation and industrialisation(102). With these affects in mind, Altomonte explains the mitigation and adaptations strategies to mitigate the possible consequences of climate change. He highlights the issue of buildings, and how they highly contribute to the issue of direct fossil fuel emissions, and therefore it is necessary that buildings reduce their dependency on fossil fuels, curb their energy demands, exploit clean power sources and minimise their wastes(103). Suitable technologies must therefore be integrated into the design of current buildings to guarantee social, economic and environmental growth. Using new design strategies is necessary to create buildings that ensure comfort and health of the staff, as well as do not negatively impact the environment. To create such a building all fields of study must be included, inclduing physchology, climatology and engineering so that there is whole understanding of the necessary features for the building to reduce emissions and include necessary social, econmic and cultural values (106). Altomonte states how these conditions of a new climate, now seem unavoidable(99), but there is solutions to be made to

The development of technology is very rapid in many industries, but in the field of construction it is very slow and lagging, as the positive side of it is unsure. The present trend of buildings is more innovative and complicated which are designed using the modern technologies, all these procedures during the development stages involves substantial

The aseismic design process for foundations is a very broad activity requiring the synthesis of insight,

Architects need to aim to have structurally sound buildings in order to prevent loss of money, supplies, and most importantly, loss of life. Structural failure occurs when a structure or structural member is unable to perform its intended purpose. This usually happens because of outside forces that the structure was not equipped to handle. Different causes for failure may be miscalculations of loads, incorrect materials, unskilled workers doing the construction work, or improper site analysis. Too often the site’s weather is overlooked, and possible natural disasters, and the loads and stresses they effect on the building, are not planned for. When designing for earthquakes, the structure needs to be able to twist and sway with the ground. For tornadoes, the structure needs to be secured to the ground and have impact-proof glass. When designing for buildings that will come in contact with large amounts of water, the structure needs to either be airtight, or sit above the predicted waterline. One of the worst things is when the reason for failure is understood, but then is allowed to occur again out of want for a lower cost or quicker finish date. Thankfully, many design and construction regulations are in place nowadays in order to help curb any structural failures that might occur when designing or while on the construction site. In the case of the Alexandria Lighthouse, the building was not designed to be able to withstand multiple earth tremors and excessive water damage,