Important Ideas and Concepts
Main Focus: Would you drive your family across that bridge in 25 years?
· Focus Points
Distribution of Force and Geometry
The geometry of an object is directly related with the distribution of force. From the basic equation Pressure = Force x Area, if we increase the area that the pressure is applied, the basic structure will be stronger. Using this principle, the spreading out of force equally and in as many ways as possible, will increase the integrity of a structure. In the case of a bridge, the basic “A-frame” or “V-frame” is very useful to increase area and equally distribute the load. When placed on top of a bridge, the structure increases tension in the supports and cross bars of the A-frame. This puts less pressure on the basic platform itself, and strengthens the system as a whole.
Motion of an Object Effects on Structure
The motion of an object on a structure is very important to take into account when designing a structure. Whether there is a 400 ton plane moving across the structure, a motorcycle driving across the structure, or a pile-driver working on the structure, the structure has to be able to withstand any stresses applied at any point on the structure. The motion of an object can greatly reduce structural integrity in certain areas, or only slightly decrease structural integrity in others depending on the structure of the system. A larger area of force applied will decrease the pressure of the load on the structure and help maintain the structural integrity of the system. Whereas a larger steel platform applies a large force over a large area, a large boulder or jack-hammer can apply the same amount of force, in a smaller area, and decrease the integrity of the system.
Safe and Stable Structures
The creation of a successful structure takes into account many principles. To be just a safe and stable structure is not enough to be a successful structure. Any structure has to not only be safe and stable, but also able to withstand many adverse conditions like weather and temperature, sustainable for many years, cost-efficient, easily maintainable, and visibly appealing. Structures are very complex systems that need to be able to fit within many parameters set by architects, designers, clients, climates, and basic opinion. Structures have to be able to withstand natural disasters, intense heating and cooling cycles, and still be able to maintain structural integrity for many years to reduce cost and labor.
Weight vs. Support for Support System
The weight applied on the system is directly proportional to the amount of support needed to maintain a stable system. The weight is created simply by the gravitational pull towards the center of earth at 9.8 meters/second2 . With increased weight, there needs to be a stronger support system and a larger area of support to equally distribute the weight and maintain structural integrity. If any part of the support system isn’t structurally sound, the system will fail if any weight is applied. When designing a support system, it is important to take into account the material weight, so not to add more weight than needed on the system. There is an important trade-off between the weight of the supports used and the amount of support it gives to the system. If the system requires a lot of support with reinforcements, it is best to look into a strong material like steel, but that has a small mass. If the ratio of mass added to the system is greater than the support added, the support system is not the ideal design.
Considerations of Mechanical Engineers
Aside from considering the basic design specifications when creating machines like cars, mechanical engineers have to take into account many outside factors. These factors include changes in humidity, temperature, extreme weather conditions, uneven and very slick road surfaces, and occurrences like car accidents and modifications. A mechanical engineer not only has to design a system that works successfully in standard conditions, but a system that can withstand many adverse conditions. A successful system is defined by its ability to function at its highest level at any time and in any condition. With different surfaces and factors affecting the performance of a system, it is important for a system to be able to function properly, efficiently, and safely.
Civil Engineering vs. Architecture
On a very basic level, civil engineering deals with the physical aspects of a structure, while an architect deals with the aesthetic aspects of a structure. Civil engineers work closely in physics, calculus, geometry, and trigonometry to create the strongest and cheapest structure while maintaining safety and future assurance of sustainability. Architects design the building to make it aesthetically appealing to the naked eye, and make it functional and creative. While architects have a wide range of possible designs for a certain structure, engineers are limited to what the architect designs, and what the laws of science will allow.