Geological survey of a site is a complex of studies that assess the soil properties and hydrogeological conditions of the area. The survey results serve as the basis for design, helping to avoid errors that could lead to deformation or failure of the structure. The analysis includes studying the soil composition, groundwater depth, and seismic activity. This data allows us to predict soil behavior under load and develop engineering solutions for safe construction.
In what cases is site geology required?
A construction site is not just a flat surface, but a complex system with unique characteristics. Ignoring this fact leads to cracks in walls, warped doorways, and foundation flooding. Surveys are ordered not only before new buildings are erected, but also during the renovation of older structures, when soil loads increase.
Geology identifies risks associated with karst voids, landslides, and high groundwater levels. Without accurate data, it is impossible to predict the behavior of the soil under structural pressure. For example, clay soils are prone to frost heave, while sandy soils are prone to subsidence.
What objects is it applied to?
The scale of the structure doesn't matter—even a lightweight gazebo requires soil analysis. Surveys are conducted for multi-story residential complexes, logistics centers, bridges, and tunnels. Private developers often neglect these surveys, but this is a mistake. Choosing the wrong foundation for a cottage can result in repairs within just 2–3 years.
The location also affects the complexity of the work. In marshy areas or on hillsides, standard solutions are not suitable. Linear structures such as gas pipelines, highways, and power lines are a special case. Here, it is important to consider changes in the ground along the entire route.
Stages
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The process begins with an analysis of archival data. Geologists study reports on adjacent sites, maps, and earthquake or flood histories. This reduces the time required for fieldwork, but does not replace it.
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Next comes drilling. The number of boreholes depends on the development area and the complexity of the terrain. The depth varies from 5 to 30 meters—sufficient to reach stable strata. Soil samples are sent to a laboratory, where moisture content, density, and chemical aggressiveness are determined.
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The final stage is office work. Engineers prepare a report with recommendations on the type of foundation, drainage system, and the need for soil compaction. This report is approved by the design organizations and becomes part of the technical documentation.
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Site geology is not a formality, but an investment in the longevity of a building. The cost of surveys rarely exceeds 1–2% of the construction budget, but it prevents the costs of remediating emergency situations.