The construction industry has a certain reputation for being a harsh environment in which brute force takes priority over calculated thought; 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 world.
One part of this unnoticed work is site surveying, or more specifically pre-demolition and post-demolition topographical surveying. This sort of work calls for a great balance of specific technical know-how as well as experience of the industry and a genuine intuition for the intricacies of the job.
Topographical Surveys
A topographical survey is a report of the actual features of a given 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 accuracy.
Topographical surveys could be carried out on a very wide range of landscapes, 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 number of factors, such as ground conditions or vegetation, and as such can be used for a number of tasks.
Common Applications for Topographical Surveys
Probably the most extensively used, and most commonly recognised application for topographical surveys is cartography, or map making. Modern day maps include a great amount of detail about the landscape they relate to, including waterways, elevations and ground surface, all of which will have been obtained via a topographical survey.
Topographical surveys also have a key role to play in the construction industry. When individuals or companies are looking to build any kind of structure they will need to perform extensive surveys as part of the design stage of the project.
Surveys definitely play a key safety role in primary industries such as mining, or in other industrial sectors that interact with the land, such as demolition and infrastructure. Businesses in these fields will use surveys to plan their projects, but also to be sure that they can ensure the safety of their workforce on site. As such, topographical surveys are often a legal prerequisite for these types of projects.
Types of Survey
The world of topography covers a large number of physical features so it is beneficial to determine what type of topographical survey is suitable for a particular scenario. A few of the more common types of survey required for construction sites are discussed below.
“Lie of the land” Surveys
These types of topographical surveys are designed to create an overview of the physical characteristics of any given plot of land. Although the information collected by the survey will be very accurate, and can be very extensive, the objective of these surveys is to give a site summary. They will usually be the first type of topographical survey that is undertaken on a project.
These surveys will generally incorporate a boundary survey that sets out to determine the extent of the site and highlight any particular restraints that are determined by the geography of the site. They may also include a level survey that will measure the elevation of the terrain and the numerous gradients that exist. A survey can be customised to specification though.
Building Surveys
Building surveys are more generally concerned with man-made structures on a site, including the surveying of special apparatus and even infrastructure characteristics. This type of study is more commonly associated with the demolition industry because it can give a detailed plan of the structure to be demolished.
A building survey will probably include a measured survey, which entails creating a comprehensive plan of the exterior and interior dimensions of a structure. Depending on the requirements of the project, a measured survey could provide basic building “footprint” dimensions, or might produce a very detailed plan of the structure. This information can be used to produce interior floor plans and even roof plans.
Content of a Topographical Site Survey
A survey of a demolition site will almost always include the details gathered by the types of boundary and building surveys mentioned above. This information will be required so the demolition company can plan a demolition that is both satisfactory and safe. Often these surveys will also be legally requested.
Surveys will often contain information about the energy services that are present on a site prior to any demolition or construction work takes place. This is an important safety aspect because any unmonitored destruction to pipes and cables carrying water, gas and electricity could be very dangerous. The information could also be used to plan new structures, based upon the existing supply of these ammenities.
Another aspect of the site survey will often be an audit of resources on the site. This type of study will be a quantity survey of the various sorts of materials that can be found on site, for example, tiles and masonry, concrete that can be used as hardcore or even timber. By taking an accurate audit of site materials the construction firm can more precisely determine the need to import building materials, or they can re-use the materials on a different job. These surveys could be made pre-demolition and post-demolition.
Project managers may uncover financial savings after topographical demolition surveys collect supplies quantities available on-site that may be recycled.
Importance of Site Surveys
Possibly the most important reason to undertake a topographical site survey is to ensure the health and safety of the people who will be doing work on the site. The industries that most commonly call for site surveys are dangerous enough as it is without having to worry about the integrity of the ground on which they are working.
Another critical reason to get a proper survey done is to highlight any potential problems that may arise because of the physical properties of the area. Certain things will not be evident on the surface of the site and will only be uncovered once digging or demolition has started. By then it may be too late to fix these problems, or at best they will be expensive issues to solve.
The inventory of site materials, as previously mentioned, can be of great value to a demolition or construction organisation working on a project. Not only are construction materials themselves costly, but transporting them to the site may be a very expensive task in itself. Any time that material can be recycled on site provides an opportunity to save development time and funds.
Topographical surveys can also highlight other areas that will be of use to the project planners. For example, if the gradients on a site would be prohibitive to particular vehicles or machinery then a new entry route or alternative equipment will have to be found.
Positioning of Survey Control
During the surveying and construction stages of a building project, the apparatus required for the physical surveying of the site and control of the survey information will often be kept on-site. This is obviously a problem when it comes to the demolition period of a project since the machinery is both costly and sensitive.
Once the demolition has occurred and the site has been deemed safe for staff to return to it, the surveying equipment can be restored to its original position on site. This will allow for effective data collecting to take place for a post-demolition survey, and maintains a single point of contact for anybody who needs the topographical survey information. Most surveying companies will oversee this redeployment.
Because of its popular use in the building business, concrete demolition forms a basic method of wok for all demolition companies.
Who can Perform Site Surveys?
Since topographical site surveys can play such a critical role in the success or failure of a construction or demolition venture it is vital that they are undertaken carefully by the right people. There are different branches of site surveying and each one will have specific certificates associated with it. Getting surveyors with these specific qualifications will certainly be advantageous.
When choosing a company to undertake the surveying work required for your project it will be sensible 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 performance on past projects.
Who will use the Survey Information?
Once an adequate level of information has been gathered by a site survey it needs to be passed out to the appropriate personnel 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 less need for materials information half way through construction for example.
Project Planners
Project planners will generally require access to all of the information gathered 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.
Demolition Experts
Demolition organisations will want to know about the internal and exterior properties of any building or structures that they are arranged to take down. Whilst every project will have individual requirements, demolition experts will typically 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 mainly interested in the survey information about the relief and topography of the site. It is usually 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 foundation for any building.