Engineering surveys are those that are associated with all aspects of engineering design, such as topographic, as-built and layout. Engineering surveys are usually much more advanced than those created by civil engineers and serve additional purposes.
They must be conducted by licensed surveyors. There are several exams and qualifications that a surveyor must attain before being able to practice engineering surveying in the USA.
What are they used for?
The main purpose of is to assess and determine the conditions of a building site either pre or post construction. They can also help assist builders, architects and civil engineers in preparing base plans.
Engineering and building surveys are an essential part of all large building constructions including roads, railways, dams, bridges and residential areas. Civil engineers in particular rely heavily on them.
Engineering surveys are a very broad category and include a range of different types to suit different purposes.
Typically they can be divided into three survey categories: planning, design and construction.
Planning surveys are completed prior to construction work at a particular site. Within planning surveys there are also investigation and channel alignment surveys. Investigation surveys can include such elements as: vertical control, gully, valley and channel cross-section surveys, and reservoir area surveys. In many cases all these different types of engineering surveys will be required to get a full picture of the site situation.
Design surveys are a group of surveys that are done during the design phase of construction – after the planning have been completed. Types nclude: structure site and channel surveys.
Finally, construction surveys are a very important category of engineering surveys. These can be done both during and after construction has been completed. Their purpose is both to keep a check over the construction process as well as to maintain the buildings once they are complete. Embankment, principal spillway, existing channel and emergency spillways surveys are just some examples of construction surveys that may be required.
A variety of methods are used for conducting these surveys – and the methods will change depending on the particular job at hand.
One of the most modern and cost-effective methods of conducting engineering surveys is using a method called lidar surveying.
Lidar surveying uses three-dimensional scanners to provide high definition measurements for use. They provide the highest possible level of detail for both interior and exterior buildings. This method, however, is only suitable for use with already-built buildings, not prior to construction.
Engineering surveys can cover a wide range of features relating to a building or construction site, even including the underground waterways. The types of features they are required to add to their survey will influence what apparatus and tools they use.
There are a range of apparatus used by professional surveyors, including theodolites, total stations, dopplers and GPS.
Some of the methods engineering surveyors may use include: differential leveling, which uses a tripod and mounted telescope to measure angles and lengths; and trigonometric leveling, using the mathematics of trigonometry.
There are also usually several people involved in the surveying process. Engineering and building surveys are very complex and cannot be completed alone. Some of the workers that may be involved include: field engineers, hydrologists and planning engineers.