How to Read a Soil Analysis Report

Before construction can begin on any project, plans must be set to build a sound, sturdy, and safe structure that’s built to last. The strongest materials and most advanced building techniques are null and void if they aren’t properly adjusted to the soil conditions at a given site.

One of the most important and often overlooked conditions to take into consideration is the condition of the soil. Certain types of soil may be susceptible to various hazards like permafrost or floods, while others may offer highly suitable surfaces that require minimal risk mitigation in the design and construction phases.

Here at Central Geotech, we’ve worked with governmental, commercial, and residential partners to conduct thorough site investigations and soil analyses. If you’re interested in learning how to read a soil analysis report, learn more with our expert team below.

Reading a Report

No matter what conditions are present at your site, working with an experienced geotechnical engineer will enable you to have confidence that the proper pre-construction testing and analysis is conducted. Let’s discuss the basics of who conducts soil testing and reading a soil test report.

When is This Completed?

Soil analysis report interpretation is done once a geotechnical engineer concludes their investigation. These highly-skilled engineers are trained in understanding site conditions and proposing mitigation plans for any potential risks. A key role in their work is investigating subsurface conditions at a proposed site, interpreting the data, and offering solutions for any problems that are uncovered in a formal report.

Soil Analysis Report Interpretation: What’s Being Tested or Analyzed?

So, what are geotechnical engineers testing for when they perform soil analysis? Primarily, geotechnical engineers test the strength, density, and composition of soil. Depending on the conditions of a given site, a soil analysis report interpretation may look at types of soils, high water tables, shifts in subsurface rock structures, as well as the soil’s response to bearing pressures, flooding, earthquakes, and more.

Types of Soil Tests

Soil testing is broken up into two main categories: field testing and laboratory testing. These tests aim to determine the suitability of building on a particular site. Primary soil tests consist of:

  1. Moisture content test: These results indicate the amount of water is present in the soil, shrinkage or swelling that soil may endure, as well as other important factors.
  2. Atterberg limits tests: This test is used to identify the shrinkage limit, plastic limit, and liquid limit of soil, helping to determine the type of soils onsite.
  3. Specific gravity of soil: These results enable geotechnical engineers to understand the porousness of soil, the stability of soil, and the soil’s ability to drain water.
  4. Dry density of soil: This identifies the amount of solids as compared to the total volume of the soil, sometimes referred to as the “unit weight”, or how much the soil “weighs”.  This parameter is critical in many types of designs.
  5. Compaction test: This test offers the optimal moisture content at which a given soil will achieve maximum dry density.  In other words, how much compaction is needed to help mitigate settlement when placing these kinds of soils onsite under foundations.

The results of these tests will guide the planning of your build towards achieving longevity. Soil tests are a highly critical part of preliminary construction planning, so working with an expert to understand and apply the results offers the best opportunity to produce an optimized structure for your given site.

Team Up With Central Geotechnical Services

If you would like personal guidance on how to read a soil analysis report, contact Central Geotech today. Our team can offer insight and education to help you better understand all phases of your construction project. Reading a soil test report and formulating a building plan based on the results is easy when you work with the right team. Consult with us today!