What is lift thickness in compaction?

What is lift thickness in compaction?

Thickness of Lift A lift that is too large could result in poor compaction and compromise stability whereas a lift that is too small would result in excessive costs and time. Lift thickness typically range from 8 to 14-inches depending on specifications.

What is suitable fill material?

Suitable fill means fill material which is stable, compacted, well graded, pervious, not adversely affected by water and frost, devoid of trash or similar foreign matter, tree stumps, or other organic material; and is fitting for the purpose of supporting the intended use and/or permanent structure.

What is optimum moisture content of soil?

Optimum Moisture Content (OMC) is the water content at which the soil attains maximum dry density. Maximum Dry Density (MDD) is the dry density of soil corresponding to Optimum Moisture Content.

What do you mean by wet side of optimum and dry side of optimum?

So, if the amount of water added is less than the optimum moisture content then it is called as dry of optimum compaction. If the amount of water added is more than the optimum moisture content then it is called as wet of optimum compaction.

What is lift thickness?

Lift thickness governs aggregate size. aggregate size to ensure aggregate can align themselves during compaction to achieve required density and also to ensure mix is impermeable. The maximum lift thickness is dependent also upon the type of compaction equipment that is being used.

What is the thickness of the compacted earth required for a top cover?

6″
Earth filling under floors should be done in layers not more than 6″ in thickness. The layer should be compacted properly. Further, the earth used for filling should be free from grass, roots, leaves and other foreign material. It should be also slightly moist which will help to achieve optimum compaction.

What is the thickness of the backfill layer?

Cohesive backfill shall be deposited in horizontal layers not exceeding 200 mm in thickness. Every layer shall be tamped in place and well compacted by means of mechanical tampers before the next layer is deposited.

What is Type A backfill material?

Type A – Classified fill, well graded, non-frost susceptible; free of shale, clay, friable material, debris; graded in accordance with ASTM C 136 within the following limits: gravelly material shall have a coefficient of uniformity Page 2 greater than four (4), and the sandy material shall have a coefficient of …

How is optimum moisture content determined?

The basic premise of this simple method to calculate OMC, optimum moisture content, is based on: One (1) cubic meter (m3) of soil/sand weighs about 1,800 kg. 200 grams of soil/sand is 1/9000th of one cubic meter of the soil/sand. ALL IS DONE BY WEIGHT and not by a percent of moisture.

What is optimum moisture content and why is it important?

The optimum moisture content provides the maximum dry unit weight that can be obtained. The increase in the dry unit weight means improving the soil properties; increased strength, decrease in permeability and compressiblity. So it is better to use the optimum moisture content.

What is dry OMC and wet OMC?

Optimum Moisture Content OMC of a soil is also called the compacted dry of optimum or wet of optimum on the dry side or wet side of OMC, respectively. The structure of a compacted soil is not similar on both sides even when the dry density is the same.

What is meant by dry side and wet side of optimum which side is preferred in the field compaction explain?

The flocculated structure on the dry side of optimum offers greater resistance to compression than the dispersed structure on wet side. So, the soils compacted dry of optimum are less compressible. The soil compacted dry of optimum have steeper stress-strain curve than those on wet side.