How to Overcome Sample Disturbance

How to overcome sample interference It is well known that high quality samples are required to obtain actual soil parameters. Basically, maintaining the natural structure of the soil and the stress conditions of the laboratory sample will determine the quality of the soil parameters. However, many researchers point out that it is impossible to preserve the original soil conditions, even if we use the same in-situ effective stress conditions as laboratory tests with so-called high quality samplers. On the other hand, many researchers have attempted to overcome the soil interference problem by introducing several methods for correcting soil parameters of inferior samples.

Soil samples are often classified as "disturbed" or "undisturbed", but "undisturbed" samples are not really disturbed. Tests on soil structure properties can not represent in-situ conditions, only the properties (eg, particle size distribution, Atterberg limit) of soil particles can be accurately determined and possibly water content. The undisturbed sample is close to the in situ soil condition sufficient to allow testing of the soil structure properties so that the soil condition in the sample approximates the in situ soil condition.

Various laboratory tests can be carried out on the soil in order to measure various soil properties. Some soil properties are inherent in the composition of the soil matrix and are not affected by sample interference but other properties depend on the soil structure and composition and for relatively undisturbed samples Only effective testing can be done. Several soil tests measure the direct nature of the soil, while others test "exponential properties" that provide useful information on the soil without directly measuring the desired properties.

Sampling: Removal of dirt from holes. Samples can be classified as either disturbed or undisturbed. Disordered samples are usually used for soil particle size analysis, liquid limit measurement, soil specific gravity, compaction test, and California loading rate (CBR). Undisturbed samples are collected at least every 5 meters and additional samples should be taken if changes occur within a 5 meter interval. Test: It refers to the determination of characteristics from the soil. The inspection can be done in the laboratory or in the field. Laboratory tests usually include moisture content, screening analysis, liquid limit, consolidation test, CBR etc. Field tests include standard penetration test (SPT), cone penetration test (CPT), and blade test.