Moisture-density relationship, Civil Engineering

Moisture-Density Relationship:

Since various compactive efforts result in varying degrees of compaction, it is necessary to standardize the compactive effort. The most well-known is the Proctor test, prescribed by IS : 2720-Part VII. This consists of compacting the soil in three layers in a mould 100 cm3 volume, with a rammer 2.6 Kg dropped from a height of 31 cm, giving 25 blows on each layer. The Proctor density so derived is used for low volume roads such as Rural Roads. For high volume highways, a heavy compaction is prescribed. The test known as modified AASHTO compaction that (IS : 2720-Part VIII) uses a heavier rammer 4.5 Kg weight, dropped from a height of 45.7 cm, the soil being compacted in 5 layers, each layer receiving 25 blows.

For controlling the density achieved in the field, a core is cut and its volume measured by pouring sand (sand replacement method). Knowing the weight of the core removed and its volume, the density is calculated. It is customary to specify 95 per cent of the laboratory MDD (modified AASHTO compaction) for embankment and 97 per cent for the subgrade for highways. For low volume Rural Roads, it is customary to specify 97 per cent of the laboratory MDD (Proctor's test) for embankment and 100 per cent for the subgrade.

Posted Date: 1/22/2013 2:49:38 AM | Location : United States







Related Discussions:- Moisture-density relationship, Assignment Help, Ask Question on Moisture-density relationship, Get Answer, Expert's Help, Moisture-density relationship Discussions

Write discussion on Moisture-density relationship
Your posts are moderated
Related Questions
Define Inspection of Pier or Abutment? Inspection of pier/abutment may then be carried out as under: i. Conduct visual inspection of the entire surface using up and down swe

How to read verniers and main scale readings on theodolite of 10"?

#estimate of rcc beam

Q. How to determine the frequency of flood? Flood frequency may be estimated preferably from flood records, if available, for a number of years or they may be based on rainfall

Explain the Precedence Relationships a. Finish-to-Start - the most common, the predecessor activity must finish before the successor activity can start b. Finish to Finish

Ask question Design the pavement by group index method for heavy traffic using following subgrade data Soil passing 75micron sieve =65%,liquid limit =40%plastic limit =20% #Min

A partially saturated soil from an earth fill has a natural water content of 19% and a bulk unit weight of 19.33 kN/m 3 . Suppose the specific gravity of soil solids as 2.7, comput


Q. Show Afflux and scour in alluvial rivers? In case of alluvial rivers, the river bed comprises scourable material like sand. Constriction of bridge waterway causes increase

Explain the Primary Treatment for Wastewater Primary Treatment: to remove the pollutants that floats or settles. Typically 60% of suspended solids and 35% of BOD 5 are removed