The construction trade has a certain reputation for being a tough atmosphere in which brute force takes precedence over calculated thought; however this image is far from correct. There is a huge amount of work that goes on behind the scenes of the demolition and construction sector that is firmly rooted in the academic arena.
One branch of this unnoticed work is site surveying, or more precisely pre-demolition and post-demolition topographical surveying. This sort of work demands a good 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 plot of land. The aim of a topographical survey is to map the naturally occurring and man-made features of a particular landscape to a high degree of accuracy.
Topographical surveys could be carried out on a very broad range of landscapes, from open countryside to urban areas 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 number of tasks. A few of the more common uses are discussed below.
Common Applications for Topographical Surveys
Probably the most widely used, and most generally recognised application for topographical surveys is cartography, or map making. Modern maps include a great amount of information about the landscape they relate to, including waterways, elevations and ground surface, all of which will have been gathered via a topographical survey.
Topographical surveys also have a key role to play in the construction business. When people or organisations are looking to build any kind of structure they will need to undertake extensive surveys as part of the design stage of the project.
Surveys also play a key safety role in primary industries like mining, or in other industrial sectors that interact with the terrain, such as demolition and infrastructure. Organisations in these industries will use surveys to plan their projects, but also to be sure that they can guarantee the safety of their workforce on site.
Types of Survey
The world of topography addresses a large number of physical features so it is important to identify what form of topographical survey is appropriate for a particular scenario.
“Lie of the land” Surveys
These types of topographical surveys are designed to create a summary 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 provide a site summary. They will often be the first type of topographical survey that is carried out on a project.
These surveys will generally include a boundary survey that sets out to define the extent of the site and spotlight any particular restraints that are determined by the geography of the site. They may also include a level survey that will plot the elevation of the terrain and the various gradients that exist.
Building Surveys
Building surveys are more typically concerned with man-made structures on a site, including the surveying of special apparatus and even infrastructure features. This type of study is more regularly associated with the demolition sector 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 detailed plan of the external and interior dimensions of a structure. Depending on the requirements of the project, a measured survey could provide simple building “footprint” dimensions, or might produce a highly detailed plan of the structure.
Content of a Topographical Site Survey
A survey of a demolition site will almost always include the information gathered by the types of boundary and building surveys mentioned above. This information will be required so that the demolition firm can plan a demolition that is both adequate and safe.
Surveys will often include information about the utility services that are present on a site prior to any demolition or construction work happens. This is an essential safety aspect because any unmonitored destruction to pipes and cables carrying water, gas and electricity might be very dangerous.
Another aspect of the site study will often be an audit of resources on the site. This type of survey 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 getting 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 project. These surveys could be made pre-demolition as well as post-demolition.
Contemporary construction and demolition companies provide details on their own corporate website so clients can see case studies or references regarding past work.
Importance of Site Surveys
Maybe the most important reason to undertake 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 be concerned about the condition 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 region. Certain things will not be evident on the surface of the site and will only be discovered once digging or demolition has begun. By then it may be too late to fix these problems, or at best they will be costly problems to solve.
The inventory of site supplies, as previously mentioned, can be of great value to a demolition or construction enterprise working on a project. Not only are building materials themselves costly, but transporting them to the site could 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. Only by taking an exact audit of these supplies can a company properly plan its imported material requirements.
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 certain vehicles or equipment then a new access 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. It is therefore wise 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 initial position on site. This will allow for efficient data collecting to take place for a post-demolition study, and retains a single point of contact for anybody who needs the topographical survey information. Most surveying firms will oversee this redeployment.
Experience is often a determining factor when selecting a buildings demolition contractor because every job has unique requirements and unique difficulties.
Who can Perform Site Surveys?
Because topographical site surveys can play such a crucial role in the success or failure of a construction or demolition project it is critical that they are undertaken carefully by the correct people. There are different divisions of site surveying and each one will have unique qualifications associated with it.
When selecting a company to undertake the surveying work necessary for your project it will be sensible to choose a company with a good reputation and a proven track record. Ask to see reviews of their previous work and try to obtain feedback about their overall performance on previous projects.
Who will use the Survey Information?
Once an adequate level of details has been gathered by a site survey it must 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.
Project Planners
Project planners will usually need access to all of the information gathered by a topographical survey, although they will particularly need to use information concerning the physical relief of a site before the design phase, and a site materials inventory before they can plan the construction phase.
Demolition Experts
Demolition companies will want to know about the interior and exterior characteristics of any building or structures that they are arranged to take down. Whilst every project will have individual requirements, demolition workers 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 particularly interested in the survey information about the relief and topography of the site. It is usually the case that they will need to assemble on a flat surface, so they will use information about the natural lay of the land to calculate what work will be required to create a stable footing for any structure. They will want this information before and in the course of the construction stage of a project.