Underground surveys are useful in many fields ranging from construction to environmental fields. Effective interpretation of subsurface conditions enables project teams to make sound decisions, avoid or reduce any adverse events, and prevent unnecessary costs. Nonetheless, an accurate survey of an area plan beneath the ground is not easy because some factors affect it. Below are the elements that should be taken into consideration to understand how successful an underground utility survey is likely to be.

1. Soil Composition and Geology

Geological structures along with the soil type significantly influence underground surveying. These types of survey methods—GPR, seismic surveys or other types of survey—will respond differently when the sub-surface is clay, sand or gravel. For instance, clay-based soils are likely to impair GPR by absorbing radar signals, although sandy-based soils are comparatively clear. Furthermore, the fact that it is often hard to penetrate the ground due to the presence of hard rock or other densely packed material may also reduce the ability of such a survey to establish the depth at which underground features may be found.

2. Moisture Content

Soil moisture plays a significant role in the transmission of the signals and may influence a survey considerably. High moisture levels mean that radar penetration can be impaired, and this forms a challenge for performing GPR surveys. On the other hand, the dry conditions are good for radar reflection resulting in clear imaging. Now, underground water is a variable and depending on the time of day or the season moisture contents may differ, and therefore surveyors need to consider moisture content at the time of surveying.

3. Depth of Survey

The degree of survey that is necessary defines the tools and instruments used. Basic surveys may use EM surveys or resistivity methods, whereas detailed surveys may use electric methods such as seismic reflection or magnetic methods. However, through high depth comes increased attenuation, which by definition makes getting accurate results more problematic. Surveyors are also interested in getting as close to the ground as possible to capture more data, but the equipment cannot allow them to do that.

4. Infrastructure development

Surveys for underground space in urban areas or near construction activities are challenging since the targets such as pipelines, cables, and foundations are already developed. These structures tromp on survey readings especially in electromagnetic surveys since they generate interference that hides the features of the target. To adjust to such environments, suitable techniques of calibration and sophisticated analysis of the collected data are necessary to distinguish between man-made structures and natural objects.

5. Equipment Selection

There is no doubt that the selection of survey equipment and techniques plays a decisive role in survey outcomes. All of them have their unique benefits and drawbacks based on the goal and scope of the project and the site features. For example, GPR is suitable for detecting non-metallic targets and for mapping objects that are close to the surface; electromagnetic methods, in turn, are suitable for detecting metal objects. The selection of a proper combination of technologies allows for achieving higher accuracy of the target survey and reducing the amount of time and effort.

Conclusion

Since there are very many factors that affect underground surveying, it is crucial to work with professional surveyors. Takhteet Survey offers precise underground surveys for your projects with the right equipment and planning. Contact us today to know more about how our Underground utility survey services in UAE can help you.