What is the definition of dry unit weight?
Dry unit weight is a measure of the amount of solid particles per unit volume. Bulk unit weight is a measure of the amount of solid particles plus water per unit volume. 5. Saturated unit weight is equal to the bulk density when the total voids is filled up with water.
What is the dry unit weight of soil?
– Wet unit weight: Unit weight of the soil when the pore are fully or partially filled with water. – Dry unit weight: Unit weight of the soil the pores are filled only with air without any water.
How does dry unit weight relate to compaction?
As water is added to a soil ( at low moisture content) it becomes easier for the particles to move past one another during the application of the compacting forces. As the soil compacts the voids are reduced and this causes the dry unit weight ( or dry density) to increase.
What is dry density of soil?
Dry density of soil is defined as the ratio of Mass of solids to the total volume of the soil. It is represented by. To obtain relationship between the moisture content and dry density, multiply the numerator and denominator of expression of dry density with “M” which is mass of soil sample.
What is maximum dry unit weight?
It is peak density of the soil taken in the driest state. The maximum dry unit weight is determined using laboratory method for the standard proctor test. From the results obtained in this test, the compaction curve is drawn.
What is the formula for dry density?
Calculate the dry density using the following equation: Dry Density (pcf) = Wet Density (pcf) – Moisture Content (pcf). 9.1. Report the moisture content of the soil to the nearest 0.1 percent and the moisture content of aggregate base materials to the nearest 0.1 pound per cubic foot.
Why is maximum dry unit weight important?
The maximum value of dry unit weight varies with characteristics of the soil and its type. This value is most important in the compaction test to obtain the optimum value of moisture content. The perfect compaction can be attained, when the soil is prepared with this value of moisture content.
What is the meaning of moisture content?
Moisture content (MC) is a reference to the amount of moisture present in a material. This value is often represented as a percentage of the material’s mass (such as X% MC). The amount of moisture in an object can be measured in several different ways, such as with oven-dry tests or moisture meters.
What is the maximum dry unit weight of soil?
Maximum dry unit weight (γd (max)) is the maximum unit weight that a soil can attain using a specified means of compaction. Optimum water content (wopt) is the water content required to allow a soil to attain its maximum dry unit weight following a specified means of compaction.
How is the degree of compaction of soil measured?
The degree of compaction of soil is measured by its unit weight, and the optimum moisture content, w c. Maximum dry unit weight (γd (max)) is the maximum unit weight that a soil can attain using a specified means of compaction.
How is the water content of soil calculated?
The compaction curve is drawn using water content in x axis expressed in percentage versus dry unit weight of compacted soil plotted in y axis. The highest dry unit weight in the graph is said to have the possible maximum value of dry unit weight.
How to calculate unit weight in dry condition?
The unit weight in the dry condition is calculated using relation given below. Here, the term γ d is the unit weight at dry state, γ is bulk unit weight and w is moisture content it is expressed in percent. The maximum value of dry unit weight varies with characteristics of the soil and its type.
