Structural engineering is the design of structural support systems for buildings, bridges, earthworks, and industrial structures. This branch of engineering focuses on supporting a load safely, and relies on principles of physics and mathematics to design these supports. The work is carried out by structural engineers, though in many areas, the lines between civil and structural engineering are blurred. As buildings become increasingly complicated, many universities and licensing boards are creating separate programs and certifications for structural engineers, helping to distinguish it as its own separate field.
The tasks involved in structural engineering are varied and complex, but the primary goal is always to develop a support system that will allow the structure to stand safely, and to minimize the risk of collapse. An engineer must account for temperature changes, weather, and many other factors during design, and choose materials that can withstand such elements. He or she must create a structure with just enough deflection and sway to account for natural shifts and expansion without creating danger or discomfort for occupants. Finally, he or she must complete the design and specify materials that fit within the project budget.
During the design of a building, structural engineers work closely with architects and other project team members. For structurally intensive projects like skyscrapers, the structural engineer often leads the design process. In cases like this, the structural elements often take precedence over architectural features, though the design must still accommodate the necessary building components such as mechanical and electrical systems.
Using columns, beams, plates, and other structural engineering elements, the engineer will design a safe, practical system of support that satisfies all project criteria. He or she may use materials made from iron or steel as the building's structural base, though pre-stressed concrete and pre-cast panels are another solid option. For smaller structures, wooden timbers can also be an effective support material, and also offer a unique look when left exposed. Other materials used by the structural engineer include aluminum and steel alloys as well as masonry units.
Due to the complexities of this field, the majority of structural engineers throughout the world have at least a four-year undergraduate degree. In most areas, structural engineering professionals must also be licensed, though requirements vary dramatically. In the US, a structural engineer must have a four or five-year degree as well as several years of work experience before he or she can apply for licensing. All potential applicants are tested using exams developed by the National Council of Examiners in Engineering and Surveying (NCEES), which is the national governing body for engineering certification.