IS 2720 Rammer Drop Height for Heavy Compaction

Indian Standard IS 2720 (Part VII)-1980/87 provides guidelines for various laboratory compaction tests on soils. This standard specifies the equipment and procedures to determine the relationship between the moisture content and the dry density of soils for a given compactive effort.

Understanding Rammer Specifications

For heavy compaction tests, the standard typically specifies the use of a specific type of rammer (also known as a tamper). Key parameters include:

• Rammer Weight: The mass of the rammer.
• Drop Height: The height from which the rammer is dropped onto the soil sample.
• Number of Blows: The number of times the rammer is dropped on each layer of soil.

IS 2720 Recommendation for Heavy Compaction

According to IS 2720 (Part VII)-1980/87, when performing heavy compaction tests, a rammer with a weight of approximately $4.9 \text{ kg}$ is used. This rammer is recommended to be dropped from a specific height onto each layer of soil placed in the mould. The standard specifies this drop height to ensure a consistent and adequate compactive effort is applied.

The recommended drop height for the $4.9 \text{ kg}$ rammer for heavy compaction, as per IS 2720 (Part VII)-1980/87, is 450 mm.

Significance of Drop Height

The drop height is crucial because it directly influences the energy imparted to the soil during compaction. A higher drop height generally results in greater compaction energy per blow. The specific value of $450 \text{ mm}$ is determined to achieve the 'heavy' compaction standard, which aims to compact the soil to a higher density compared to light compaction methods.