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
describe gunters chain in survey


Define the Impact Damage - underwater inspection of bridge? Impact from moving vessels or logs carried during the floods can inflict damage to the structure. The impact or coll

Calculate the Poissons Ratio: In separate experiments, Young's Modulus and Rigidity Modulus of a material have been determined as 120 GPa and 50 GPa respectively. Calculate th

Define Remedial measures for Problems in Turbid Water - Refraction? There is little that can be done to overcome the effects of refraction. Image definition and contrast in tur

Q. How can a temporary diversion to laid a cross flowing river in case of disruption to rail traffic over a major bridge lasting over 6 months. Ans.- Temporary diversion

Thermal stresses: In Thermal stresses, you have studied (a) The effect of temperature on bodies and materials, (b) The concept of thermal stresses, and (c) The techni

Question What is the major purpose of carrying out water absorption test for precast concrete pipes? Answer Cement will mix with additional water than is compulsory t

Q. Minimum and maximum distance between bars? Minimum distance between bars and maximum distance between bars In some codes, a minimum distance amid bars is specified to

construction & working of rope brake dynamometr