Topographical Demolition Site Surveys
March 9th, 2010
The demolition industry has a certain character for being a harsh atmosphere in which brute force takes priority over calculated thought; however this image is far from appropriate. There is a huge amount of work that happens behind the scenes of the demolition and construction industry that is firmly grounded in the academic world. Furthermore, this unseen work is vital to the success of the more visible procedures.
One branch of this unnoticed work is site surveying, or more precisely pre-demolition and post-demolition topographical surveying. This kind of work calls for a good balance of specific technical know-how as well as experience of the industry and a genuine intuition for the complexities of the job.
Topographical Surveys
A topographical survey is a study of the actual features of a particular plot of land. The purpose of a topographical survey is to map the naturally occurring and man-made traits of a specific landscape to a high degree of accuracy. Whilst topography itself may refer to the surface of virtually any object, it is more commonly associated with the surface of the planet.
Topographical surveys can be carried out on a very wide 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 number of factors, such as ground conditions or vegetation, and as such can be used for a number of tasks. A few of the more common uses are outlined below.
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 deal of detail about the terrain they relate to, including waterways, elevations and ground surface, all of which will have been collected via a topographical survey. This information is also being offered online.
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 carry out extensive surveys as part of the design phase of the project.
Surveys definitely play a key safety role in primary industries such as mining, or in other industries that interact with the land, such as demolition and infrastructure. Companies in these fields will use surveys to prepare their projects, but also to make sure that they can guarantee the safety of their workforce on site. As such, topographical surveys are often a legal prerequisite for these types of projects.
On sites where there are structures to get demolished, building demolition surveys generally assist strategists during the demolition stage of the job.
Types of Survey
The arena of topography addresses a large number of physical features so it is beneficial to identify what form 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 a summary of the physical properties of any given plot of land. Although the information collected by the survey will be extremely accurate, and may be very extensive, the purpose of these surveys is to provide a site summary.
These surveys will generally include a boundary survey that sets out to define the extent of the site and highlight any specific 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 constructions on a site, including the surveying of special machines and even infrastructure features. This type of survey is more regularly associated with the demolition industry because it can give a detailed plan of the building to be demolished.
A building survey will almost certainly include a measured survey, which involves 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” measurements, or might produce a very detailed plan of the structure.
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 described above. This information will be required so that the demolition firm can plan a demolition that is both satisfactory and safe. More often than not these surveys will also be legally required.
Surveys will often include information about the energy services that are present on a site before any demolition or construction work happens. This is an important safety factor since any unmonitored destruction to pipes and cables carrying water, gas and electricity might be very dangerous. The information could also be used to plan new structures, based upon the existing availability of these utilities.
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 kinds of materials that can be found 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 company can more accurately gauge the need to import building materials, or they can re-use the materials on a different job. These surveys can be made pre-demolition as well as post-demolition.
It is an apparent truth that prior to construction demolition has to be completed in sites containing existing houses and other structures.
Importance of Site Surveys
Perhaps the most significant reason to perform a topographical site survey is to ensure the safety of the people who will be working 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 proper survey done is to identify any potential difficulties that may arise because of the physical characteristics of the region. Certain things may not be evident on the surface of the site and will only be uncovered once digging or demolition has begun. By then it may be too late to fix these problems, or at best they will be costly issues to solve.
The inventory of site supplies, as previously mentioned, can be of great benefit 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 provides an opportunity to save development time and money.
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 certain vehicles or equipment then a new access route or alternative machinery will need to be found.
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 stored on-site. This is obviously a problem when it comes to the demolition phase 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 original position on site. This will allow for effective data gathering to take place for a post-demolition study, and retains a single point of contact for anybody who needs the topographical survey information.
The need for strict control as well as planning is crucial for garage demolition projects since homes or other buildings may be close by.
Who can Perform Site Surveys?
Because topographical site surveys can play such a vital role in the success or failure of a building or demolition venture it is vital that they are carried out thoroughly by the correct people. There are different divisions of site surveying and each one will have specific certificates associated with it. Getting surveyors with these specific skills will certainly be advantageous.
When selecting a company to undertake the surveying work required for your project it will be wise to choose a company with a good reputation and a proven track record. Ask to see examples of their previous work and try to obtain feedback about their performance on past projects.
Who will use the Survey Information?
When an adequate level of information has been gathered by a site survey it needs to be handed out to the appropriate people on-site. Who gets which pieces of information will largely 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 about the physical relief of a site before the design phase, and a site materials record before they can plan the construction phase. The more data that can be made available to project planners will help the smooth running of the venture.
Demolition Experts
Demolition companies will want to know about the internal and exterior properties of any building or structures that they are set to take down. Whilst every job 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 mainly interested in the survey information about the relief and topography of the terrain. 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 calculate what work will be required to create a stable foundation for any building. They will want this information before and in the course of the construction stage of a job.
Categories: General Interest |
