Above and beyond
Broadly, both the main disciplines of surveying are involved with the planning and setting out of highways across the UK. Above ground, our surveyors will carry out the setting out of the route, its levels and contours, while above and below ground, topographical surveys and underground utility surveys can provide vital information at the planning stage about what construction teams can expect to face en route. Accuracy is essential when setting out infrastructure layouts. Using the latest digital technology, including Leica robotic total stations and GPS equipment, our site engineers ensure that all setting out is carried out to a high degree of precision and efficiency.
Setting out linear highway projects
Highway projects are obviously different in the demands they place on the construction team while they are being built. They are linear projects, often over many miles, and may include such engineering aspects as bridges, flyovers and underpasses. There is also a myriad of other features required, such as drainage works or highway upgrades to include cycle lanes. It’s much more than simply building a road surface, and the geospatial surveyors’ role is important throughout the construction process. Accounting for the curvature of the earth using Snake Grid, and therefore a single coordinate system, is imperative to correctly setting out any long road. In addition, a geospatial surveyor or surveying engineer will be able to understand what the reading on the survey equipment means and be able to adjust it in order to continue their work with the correct information.
Routes to success
Before the highway can be built or upgraded however, it will need to be planned and mapped out. A route will have to be plotted and this may be decided by a number of factors. A topographical survey carried out in conjunction with an underground utilities survey can be useful in finding out if there are any major obstacles or underground services to be considered. Existing data, such as construction records or maps, will be useful, but the more up-to-date the data, the better. This is especially true if the route passes through an area that has been previously developed, such as a brownfield site, where there may be underground utilities hidden from plain view.
Topographical surveys meanwhile provide a complete picture of the route above ground. They will also identify any boundaries the highway may be approaching – or even encroaching on – and watercourses that will have to be navigated. It can be useful too in areas where there are any number of natural obstacles, such as trees with tree preservation orders on them, which prevents them from being taken down. Topographical surveys will also establish levels and any elevation that the route will have to negotiate. This may involve additional engineering groundwork, which will have to be factored into the construction.
Combine your Topo and Utility Detection Surveys
Topographical and utility surveys can then be used as the basis of the layout of the road system, with the plotting of the route an overlay onto the topo survey itself. For those tranches of road that don’t have a corresponding topographical survey, one can easily be completed and added to the current topographical road layout by a survey company using the same co-ordinate system and scale factor. Having one firm, such as Powers, carry out the entire survey and setting out process will guarantee that the compatibility and accessibility of all aspects of the design and construction planning are entirely interconnected throughout. This will ensure a smooth and efficient project and deliver a successful outcome for both client and contractor.
Find out more about geospatial and land surveys at Powers: www.powersuk.com