The construction trade has a certain character for being a tough environment in which brute force takes priority over calculated thinking; however this image is far from appropriate. There is a huge amount of work that goes on behind the scenes of the demolition and construction sector which is firmly grounded in the academic arena.
One branch of this unnoticed work is site surveying, or more specifically pre-demolition and post-demolition topographical surveying. This sort of work calls for a good balance of specific technical knowledge as well as experience of the industry and a natural intuition for the complexities of the job.
Topographical Surveys
A topographical survey is a study of the physical features of a particular piece of land. The aim of a topographical survey is to map the naturally occurring and man-made traits of a particular landscape to a high degree of precision.
Topographical surveys could be carried out on a very broad range of environments, from open countryside to urban developments and across a variety of elevations and land surfaces. Surveys can be developed to take into account a great many factors, such as ground variables or vegetation, and as such can be used for a multitude of tasks.
Common Applications for Topographical Surveys
Perhaps the most extensively used, and most generally recognised application for topographical surveys is cartography, or map making. Modern maps include a great amount of detail about the landscape they relate to, including waterways, reliefs and ground surface, all of which will have been obtained via a topographical survey.
Topographical surveys also have a major role to play in the construction industry. When individuals or organisations are looking to build any kind of structure they will need to carry out extensive surveys as part of the design phase of the project.
Surveys definitely play a key safety part in primary industries like mining, or in other industrial sectors that interact with the land, such as demolition and infrastructure. Companies in these industries will use surveys to plan their projects, but also to make sure that they can guarantee the safety of their workforce on site.
New developments built on previously lived on land require demolition surveys to minimise interruption to utilities and services for the surrounding community.
Types of Survey
The world of topography covers a large number of physical features so it is important to determine what type of topographical survey is appropriate for a particular scenario.
“Lie of the land” Surveys
These types of topographical surveys are designed to create an overview of the physical properties of any given plot of land. Although the information collected by the survey will be very accurate, and might be very extensive, the purpose of these surveys is to give a site summary. They will often be the first type of topographical survey that is undertaken on a job.
These surveys will generally include a boundary survey that sets out to define the extent of the site and spotlight any specific restraints that are determined by the geography of the site. They can also include a level survey that will measure the elevation of the terrain and the numerous gradients that exist. Any survey can be customised to specification though.
Building Surveys
Building surveys are more typically concerned with man-made structures on a site, including the surveying of special machines and even infrastructure features. This type of study is more commonly associated with the demolition industry since it can give a detailed plan of the structure to be demolished. It can be used for other projects as well.
A building survey will almost certainly include a measured survey, which entails creating a precise plan of the exterior and interior dimensions of a structure. Depending on the requirements of the job, a measured survey could provide simple building “footprint” measurements, or might produce a highly detailed plan of the structure.
Content of a Topographical Site Survey
A survey of a demolition site will almost definitely include the details gathered by the types of boundary and building surveys described above. This information will be required so that the demolition firm can plan a demolition that is both adequate and safe. More often than not these surveys will also be legally requested.
Surveys will often contain information about the energy services that are present on a site before any demolition or construction work happens. This is an important safety factor because any unmonitored damage to pipes and cables carrying water, gas and electricity could be very dangerous.
Another aspect of the site survey will often be an inventory of resources on the site. This type of study will be a quantity survey of the various types of materials that can be located on site, for example, tiles and masonry, concrete that can be used as hardcore or even wood. By taking an accurate audit of site materials the construction company can more precisely gauge the need to import building materials, or they can re-use the materials on a different project.
Even though it is one necessary short-term cost, a pre demolition survey could produce economic rewards in the long-term by identifying potential issues.
Importance of Site Surveys
Maybe the most important reason to perform a topographical site survey is to ensure the safety of the individuals who will be doing work on the site. The industries that most commonly call for site surveys are risky enough as it is without having to worry about the condition of the ground on which they are working.
Another important reason to get a suitable survey done is to identify any potential difficulties that may arise because of the physical characteristics of the region. Certain things will not be evident on the surface of the site and will only be uncovered once digging or demolition has started.
The inventory of site supplies, as previously mentioned, can be of great value to a demolition or construction company working on a project. Not only are building materials themselves expensive, but importing them to the site may be a very expensive task in itself. Any time that material can be reused on site offers an opportunity to save development time and funds.
Topographical surveys can also identify other areas that will be of use to the project managers. For example, if the gradients on a site would be prohibitive to particular vehicles or equipment then a new entry route or alternative equipment will have to be found. Equally, an appropriate site will need to be found for the base of management operations for the project. Good site surveying can help out in these less tangible ways.
Positioning of Survey Control
During the surveying and construction stages of a construction project, the apparatus required for the physical surveying of the site and control of the survey data will often be kept on-site. This is obviously a problem when it comes to the demolition phase of a project since the equipment is both costly and sensitive. It is therefore sensible to move this equipment off-site during demolition.
Once the demolition has taken place and the site has been deemed safe for workers to return to it, the surveying equipment can be restored to its original position on site. This will allow for efficient data gathering to take place for a post-demolition study, and maintains a single point of contact for anyone who needs the topographical survey information.
Las Vegas is the backdrop for much commercial demolition since old hotels require flattening so that new ones may be built in their place.
Who can Perform Site Surveys?
Because topographical site surveys can play such a vital role in the success or failure of a construction or demolition project it is critical that they are carried out thoroughly by the correct people. There are different branches of site surveying and each one will have specific qualifications associated with it. Getting surveyors with these specific skills will certainly be advantageous.
When choosing a company to undertake the surveying work required for your project it will be wise to choose a business with a good reputation and a proven track record. Ask to see reviews of their previous work and try to get feedback about their overall performance on past projects. It may also be worth considering how a company can deliver their survey data, i.e. in 3-D models or CAD ready formats, for ease of integration with other members of the project staff.
Who will use the Survey Information?
When an adequate level of information has been gathered by a site survey it needs to be passed out to the appropriate people on-site. Who gets which pieces of information will mostly depend on the job roles being executed, but can also rely on the stage that a project is at. There will be much less need for materials information midway through construction for example.
Project Planners
Project planners will generally need access to all of the information collected by a topographical survey, though they will particularly need to use information about the physical relief of a site before the design phase, and a site materials inventory before they can prepare the construction phase. The more information that can be made available to project planners will assist the smooth running of the venture.
Demolition Experts
Demolition companies will want to know about the internal and external properties of any building or structures that they are arranged to take down. Whilst every project will have individual requirements, demolition workers will generally need to know about the fundamental framework of a building and the materials it is made out of.
Site Engineers
Construction engineers on-site will be particularly interested in the survey data about the relief and topography of the site. It is normally the case that they will want to build on a flat surface, so they will use information about the natural lay of the land to determine what work will be required to create a stable footing for any building.