ᐅ Structural analysis: Poor soil conditions

Hello,

I have a plot of land and would like to build a single-family house on it. I have already had a soil report conducted. It turned out that the soil is not particularly load-bearing (silty, sandy) with a bearing capacity of 100. The geologist recommends a 1.20 m (4 feet) thick soil cushion and suggests having a structural engineer calculate everything further, as there may be subsequent settlements of 2–4 cm (1–1.5 inches). What will the structural engineer generally recommend, or what measures can be taken to safely build a house on this soil/foundation cushion?

Thank you gerrko

The measures are usually included in the soil report as foundation recommendations. Our situation is similar. A depth of 1.40m (4.6 feet) had to be excavated and replaced with different layers of gravel. Additionally, geogrids and drainage were installed.

@Masipulami, could you share approximately how much the replacement cost? We received our soil report today, and it looks really bad—clay, silt, sand, etc.…

Including all work, materials (gravel, geotextile, drainage), and removal of excess soil, the total cost is approximately 15,000 €.

Oh dear… It's a good thing to plan for contingencies.

Thank you for the response!

What is important is what is stated in the section The Foundation Recommendation. It depends on how much and in what proportion clay, silt, and sand are present.