What You need To Know About Surveying In Civil Engineering!

The success of many construction projects, from homes and businesses to infrastructure, depends on civil surveying. It helps project managers and engineers map out how their project should proceed and provides the geographic data they need to construct a building that will withstand the local terrain with reliability.

What is Surveying?

Surveying is a technique for measuring the earth's surface at large scales. It involves selecting the measurements, condensing and interpreting the data into a form that can be used while establishing the relative size and position per the specified measurement standards. Hence, surveying serves two related but distinct purposes: establishing markings to regulate buildings or delineate property lines; and determining the relative horizontal and vertical position of an object, as in the case of mapping.

What is the Purpose of Surveying?

In any civil engineering project, surveying plays a critical role. Creating a plan and a portion of the project's area is a prerequisite for surveying. Depending on the project's needs, the optimal alignment, quantity of earthwork, and other parameters can be determined from these produced maps and sections.

All civil engineering projects, including airfields, ports, railroads, highways, tunnelling, irrigation, dams, reservoirs, waterworks, and enormous structures, are planned and designed using surveying measures.

Any size project is constructed along the lines and points established by surveying before execution.

Without surveying, it is impossible to fix a piece of land's size and boundaries. It is impossible to determine the economic feasibility of a project without surveying and it helps create a topographic map of the earth's land surface.

What are the Types of Surveying?

Civil engineers often use a wide range of surveying methods. The most common ones are:

Triangulation:

It is a method for measuring angles from a surveying station that involves connecting and overlapping triangles.

Trilateration: 

It utilises a similar methodology to triangulation and uses an electronic distance metre (EDM).

Traverse: 

To measure angles and distances, this method connects many lines that have already been measured to the same length.

Levelling: 

Using graded rods, this technique measures the variations in terrain's heights.

Radiation:

This technique draws radiating lines from a focal point to defined boundaries and converts them to a small-scale surveying sheet.

Modern Surveying uses digital devices, GPS systems, drones and other technologies to calculate a range of measurements like angles, levels and distances even from inaccessible sites. The common methods are:

Geodetic Surveying:

Surveys are carried out on a large scale with the help of control networks spanning over long distances.

Cadastral Surveying:

Surveys are carried out to define land ownership and boundaries.

Topographical Surveying:

Surveys are carried out to determine the land structure and variation in land heights.

Photogrammetry (Aerial Surveying):

Aerial surveys are conducted using photogrammetry, capturing pictures from high-ground stations.

LiDAR (Aerial Surveying):

Distances are measured during surveys using remote sensors and laser light that is reflected.

What is Surveying and Geospatial Study?

Surveying is related to the broad areas of spatial science. Spatial means “the relative place or location of something”. Geospatial science helps to understand the relationship between the community and the environment to help predict trends and patterns. Surveying is first done to establish the boundaries, and spatial technologies are used to interpret and report on the data.

The main surveying specializations are land, mining, engineering and hydrographic. Other spatial science fields include geodesy, topographic surveying, remote sensing and Geographic Information Systems (GIS). Head on over to our specializations page for more information.

What is a Drone Survey?

An unmanned aerial vehicle (UAV) is used in a drone survey to collect aerial data with downward-facing sensors like RGB or multispectral cameras and LIDAR payloads. The ground is photographed numerous times from various angles during a drone survey with an RGB camera, and each image is tagged with coordinates.

To create detailed 2D and 3D maps, photogrammetry combines photos of the same spot on the ground taken from various angles.

A photogrammetry programme can produce georeferenced orthomosaics, elevation models, or 3D models of the project area using this data. These maps can also be used to extract data, such as volumetric measurements or highly precise distances.

Drones can fly at far lower altitudes than piloted aircraft or satellite imaging, accelerating the production of high-resolution, high-accuracy data and making it independent of atmospheric factors like cloud cover.

Why do we need Drones for Surveying?

Below are the benefits of drones in surveying:

Reduce costs and time.

Drones can collect topographic data up to five times more quickly and with less labour than traditional methods. You can also save time using PPK geo-tagging since installing several GCPs is no longer essential. In the end, you deliver your survey data more quickly and for less money.

Provide precise and comprehensive data

Total stations measure only individual points. A single drone flight generates thousands of metrics that can be shown in several formats (orthomosaic, point cloud, DTM, DSM, contour lines, etc). Each point in the 3D model or pixel of the generated map comprises 3D geo-data.

Map otherwise inaccessible areas

An aerial mapping drone can take off and fly almost anywhere. Unreachable areas, unsafe steep slopes or harsh terrain unsuitable for traditional measuring tools no longer limit you. Roads and railroad tracks don't have to be shut down. In reality, you can collect data while operations are running without incurring organisational costs.

How accurate is a drone survey?

The effectiveness of drone survey mapping can be greatly impacted by the type and performance of the drone, the calibre of its parts, the camera resolution, the height at which the drone flies, the vegetation, and the technique and technology used to geolocate aerial photos. With a high-end surveying drone like the WingtraOne, it is currently possible to achieve an absolute accuracy down to 1 cm (0.4 in) and 0.7 cm/px (0.3 in/px) GSD in ideal circumstances.

Advancements in Surveying

1. Geospatial technology advancements: To increase the accuracy and effectiveness of their work, land surveyors are increasingly adopting modern geospatial technologies like unmanned aerial vehicles (UAVs), Light Detection and Ranging (LiDAR), and Global Navigation Satellite Systems (GNSS).
2. Integration of Artificial Intelligence (AI) and Machine Learning (ML): The integration of AI and ML is helping land surveyors to automate data processing and analysis and to identify patterns and trends that may not be easily discernible through traditional methods.
3. Use of Virtual and Augmented Reality: Land surveyors are exploring virtual and augmented reality technologies to create immersive 3D models of surveyed areas, which can be used for design and planning.
4. Greater Emphasis on Environmental Sustainability: Land surveyors are increasingly considering environmental sustainability considerations in their work, such as using eco-friendly surveying equipment and considering the impact of construction projects on the surrounding environment.
5. Improved Data Management: With the increasing amount of data collected through land surveying, there is a greater emphasis on improved data management techniques, including using cloud-based platforms and data analytics tools.
6. Collaboration and Integration with Other Disciplines: Land surveyors are increasingly collaborating with other disciplines, such as architecture and engineering, to ensure that the data they collect is effectively integrated into broader design and planning processes.