Compaction Tests and empirical relations.

Presentation byJyoti KhatiwadaRoll no. 10

What is a Proctor test?

The Proctor compaction test is a laboratory method of experimentally determining the optimal moisture content at which a given

soil type will become most dense and achieve its maximum dry density

Compaction (Soil Compaction) is the process of applying energy to loose soil to consolidate it and remove any voids, thereby increasing the density and consequently its load-bearing capacity.

What is the purpose of the Proctor test?

• The Proctor compaction test is a laboratory geotechnical testing method used to determine the soil compaction properties, specifically, to determine the optimal water content at which soil can reach its maximum dry density

Modified Proctor test appartus

• These laboratory tests generally consist of compacting soil at known moisture content into a cylindrical mold of standard dimensions using a compactive effort of controlled magnitude.

• The soil is usually compacted into the mold to a certain amount of equal layers, each receiving a number of blows from a standard weighted hammer at a specified height. This process is then repeated for various moisture contents and the dry densities are determined for each.

• The graphical relationship of the dry density to moisture content is then plotted to establish the compaction curve.

• The maximum dry density is finally obtained from the peak point of the compaction curve and its corresponding moisture content, also known as the optimal moisture content.

Compaction curves• A large number of compaction curves pertaining to a wide

variety of fine-grained soils were collected and used in modeling. The developed modules were able to predict compaction curves of soils with good accuracy, with the ANN-based module outperforming the statistical-based analog..

• The compaction modules were utilized to inquire about the compactibility behavior of fine-grained soils in relation to their properties and the compaction energy used

• The point at which this transition occurs is called the optimum compaction point (OCP), which relates two key compaction characteristics: the maximum dry density (MDD) and the corresponding optimum water content (OWC). The portion of the curve to the left of the OCP is named dry of optimum (DOO) and that to its right wet of optimum (WOO), as shown in Fig. 1. Because of the bell-shaped nature of the compaction curve, soil may be compacted to equal density at two different water contents.

Empirical relation for compaction test

• Thank you