Structural Engineering is a subset of civil engineering, where structural engineers are trained on how to design the “bones and muscles” that make the actual form and structure of man-made structures. This type of engineering has very high standards in what it takes to build commercial and residential buildings as well as structures for the military. There are many areas that fall under the category of structural engineering. These include structural steel, reinforced concrete, column line steel, masonry, piping, interior support, doors, window panes, roofing, walls, and earthquake response.
The field of structural engineering has many uses. One of the most popular of these uses is the construction and design of bridges. Bridges are one of the most important pieces of road building and transportation. A quality structural engineer can help determine the proper specifications for a structure, which will make the structure able to withstand any weather condition. According to Allen Fiford, Director at AF Consulting Engineers & Associates, specifications often refers to a set of documented requirements to be satisfied by a material, design, product, or service. When specifications are provided by a Structural Engineer, it is often a type of technical standard. “There are different types of technical or engineering specifications and the term is used differently in different technical contexts,” he elaborates.
“A Specification is basically a document that describes the scope of work, the type of materials to be used, the quality of workmanship and the methodology of installation in a specific contract. This is to be used and read in conjunction with contract construction drawings. The specification is a living document to be used by the project team during the construction phase; its value does not terminate at the design phase,” defines Eng. Gibson N. Wanjau, Director & Principal Engineer at EL ARCA Engineering.
To the best of his knowledge, Eng. Wanjau further points out the proper Specifications for a Structure should;
1. Clearly define the Materials and manufacturers’ items to be used on site
2. Back up the cost of the project, not only the materials and products but also the performance and workmanship of the contractor.
3. Identify installation, testing and handover requirements.
4. Be clear, and rich in information to provide answers to the many construction questions on site, saving the project team, contractor and client time and money
5. Assist in minimizing project risk and providing support should there be any legal disagreements.
6. Reference the quality and standards which should be applied on a construction project.
Structural engineer also ensures that all the necessary tests are passed before any construction project is put into use.
Another application of structural engineering deals with the prevention of structural failure. All structures, including buildings, have the potential for failure at some point. This is when the effects of stress are greatest. The primary reason for structural failure is the rate of change of a structure’s load-bearing capacity and load distribution. For example, if a heavy load is placed on a weak point, the structure can experience structural failure. If the load changes, the strength of the structure can decrease or the force by which the structure compresses or grows can change, affecting the performance of the structure.
However, Allen believes that, in the construction industry or build environment, defective construction which causes failure may be caused due to numerous/several reasons that may not be easy to predict before or during the construction of a project. The major causes of structural failure are defective designs that have not determined the actual loading conditions on the structural elements. Inferior construction materials may also be the cause since the loads are calculated for materials of specific characteristics. Structures may fail even if the design is satisfactory, but the materials are not able to withstand the loads.
“We at AF Consulting Engineers & Associates have witnessed in many scenarios where employment of unskilled labour in construction work becomes a huge problem, this is another reason for why we witness structural failures. Hence the reason why it is so important to appoint reputable professionals to educate, designers builders, homeowner builder’s…etc., to make each party fully conscious of the reasons why structures fail, and undertake all preventive measures preventing structures from failing,” he recommends.
Conforming to Allen, failures occurs very rarely as a result to inadequate design, more often because of bad construction practice, either due to ignorance or cutting corners for profit. “This is where supervision comes in and therefore our fees as professionals should be respected,” he concludes.
“Structural elements tend to fail because of use of substandard materials, error in Structural designs, the methodology of construction, external/environmental conditions and the usage to which the building is put,” says Eng. Wanjau. He supplementary expand on possible causes of structural failure;
1. Use of Substandard Materials and Lack of quality control
This happens when the contractor/builder decides to use inferior materials to put up the structure. E.g., Use of the wrong mix ratio of concrete (of lower class than specified). Failure may also occur due to contractor and Engineer’s inadequate supervision and control of operations and material quality.
2. Methodology of Construction
The contractor’s failure to construct in accordance with drawings and specifications given by the engineer can also be a cause or reason for failure of structures.
3. External/Environmental Conditions
These are often natural, such as unexpected loads, heavy rain, earthquakes and maybe defective sites, which may have unusual ground conditions e.g., sinking holes or even swampy land.
4. Error in Structural designs
Error in design don’t only mean errors of computation, but also it can be a failure to account for loads the structure will be expected to carry, reliance on inaccurate data and improper choice of materials and their properties.
5. The Structure Usage
Every structure is designed and built to withstand a certain amount load. A residential house is designed to withhold the weight of the residents living in it. If the same building is used as a warehouse, then that structure stands at a risk of being overstressed.
Structural engineers perform an assortment of tasks within a building. Many of these engineers will be involved in the planning process, which will determine many of the building’s characteristics. They will be responsible for determining the structural integrity, load bearing ability, and conditions of the structure, among other things. Structural engineers can also implement many of the building’s controls, ensuring that they work correctly, and can monitor the overall effectiveness of the facility.
Many construction projects in earthquakes zones require the help of structural engineering. In addition to assisting in the planning and execution of the project, structural engineers must ensure that the integrity of the buildings is not compromised. They perform tests on beams and walls, as well as check for weak areas. In many cases, structural engineers must also rebuild the entire project of the facility after a major disaster.
Civil engineers may also be called upon during a large earthquake to inspect any damaged areas and ensure that safety regulations have been followed.
Many smaller civil engineering firms specialize in a particular segment of the field. Some specialize in projects that focus on the residential market, while others focus on commercial projects such as apartment complexes and office buildings. Structural engineers may choose to work on either a specialty or multi-specialty basis, depending on the type of structure they are working on. Whatever the case, it is almost certain that structural engineering will continue to grow in importance as time goes by.
