Kenttätiivistystestit

Kenttätiivistystestit, often translated as field compaction tests, are a group of procedures used to determine the degree of compaction achieved in a soil layer during construction. Compaction is the process of increasing the density of a soil by mechanically reducing its air voids. Achieving proper compaction is crucial for the stability and performance of various civil engineering structures, such as roads, embankments, and foundations. These tests are performed directly on the construction site to monitor and control the quality of the compaction work.

The primary goal of field compaction tests is to ensure that the in-situ density of the soil is close to its maximum possible density, as determined by laboratory compaction tests like the Proctor test. The degree of compaction is typically expressed as a percentage of the maximum dry density obtained in the laboratory. A common target for the degree of compaction is 95% or higher, depending on the project specifications and the type of soil.

Several methods exist for performing field compaction tests. One common technique involves excavating a small volume of soil from the compacted layer, measuring its weight, determining its water content, and then calculating its in-situ dry density. The volume of the excavated hole can be measured using sand cone methods or rubber balloon methods. Nuclear density gauges are also widely used, offering a rapid, non-destructive way to estimate soil density and moisture content by measuring the scattering and absorption of radiation. The results of these tests allow engineers to adjust the compaction effort, such as the number of passes or the type of equipment, until the desired level of compaction is achieved.