What is the difference between standard and modified Proctor tests?

What is the difference between standard and modified Proctor tests?

Standard proctor test – whole soil sample is compacted in 3 layers with 25 evenly distributed blows on each layer with 2.5 kg rammmer and free fall of 300 mm. In Modified proctor test- whole soil sample is compacted in 5 layers with 25 evenly distributed blows on each layer from 4.6 kg rammer with free fall of 450 mm.

What is a standard Proctor test?

Standard Proctor Test is used to determine the compaction of different types of soil and the properties of soil with a change in moisture content.

What is the energy imparted by the standard and modified compaction test?

As noted in Table 1, the Modified test imparts approximately 4.5 times the energy (2703 kJ/m 3 ) per unit volume as the Standard test (596 kJ/m 3 ).

What is the aim of standard Proctor compaction test?

The Proctor compaction test is a laboratory method of experimentally determining the optimal moisture content at which a given soil type will become most dense and achieve its maximum dry density.

What is FDT test?

Soil field density test (FDT) is a common test conducted in construction work especially the one related to earthwork. This relative density is measured by comparing maximum dry density obtained from field test with maximum dry density of laboratory test as a standard reference.

What for a proctor needle is used?

Proctor needles are used for quick evaluation of maximum soil density in the field. Standard Compaction curves showing moisture contents versus densities are drawn in laboratory using standard compaction method and penetration of the proctor needles are correlated.

How do you perform a proctor test?

The procedure of the Proctor Compaction Test consists of the following steps:

1. Obtain about 3 kg of soil.
2. Pass the soil through the No.
3. Weight the soil mass and the mold without the collar (Wm).
4. Place the soil in the mixer and gradually add water to reach the desired moisture content (w).
5. Apply lubricant to the collar.

What is Proctor value of soil?

The Proctor compaction test provides a standardized method of determining a soil’s resistance to compaction over a range of soil water contents under a constant value of compaction energy. The optimum water content (OWC) is the amount of water required to produce a maximum dry density (MDD) from the test procedure.

What is MDD and OMC?

MDD – Maximum Dry Density. MWD – Maximum Wet Density. OMC – Optimum moisture Content. Zero Air Voids – is the relationship between dry density and corresponding moisture contents, for a specific particle density, assuming that all of the voids are completely filled with water.

How do you calculate compaction?

Divide the volume of the loose trash by the volume of the compacted trash to achieve the compaction ratio. As an example, 16 cubic feet of loose trash compacted into a 4 cubic feet volume would have a ratio of four, or four to one.

Why is maximum dry density important?

Maximum dry density (MDD) of stabilized soils is generally an important factor in determining the soil suitability or unsuit- ability for stabilization. The properties of a compacted soil mixture are influenced more by its moisture content than by the other reasons.

What is meant by dry density?

The weight of a unit volume of a dry sample of soil, after the latter has been heated at a temperature of 103 degrees C. Ref: Hammond. Prev: dry deltaNext: dry density/moisture ratio Glossary Search.

What is density of soil?

and the densities of soil mineral (sand, silt, and clay) and organic matter particles, as well as their packing arrangement. As a rule of thumb, most rocks have a bulk density of 2.65 g/cm3 so ideally, a medium textured soil with about 50 percent pore space will have a bulk density of 1.33 g/cm3.

What is void ratio formula?

The void ratio is the ratio of the volume of voids (open spaces, i.e. air and water) in a soil to volume of solids. Where: e = Void Ratio. Vv = Volume of voids (m3 or ft3) Vs = Volume of solids (m3 or ft3)

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.

How do you calculate water content?

The amount of water is determined by subtracting the dry weight from the initial weight, and the moisture content is then calculated as the amount of water divided by the dry weight or total weight, depending on the reporting method. Even this simple loss-on-drying method is mined with potential variability traps.

What is the 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.

How do u calculate mass?

The mass of an object can be calculated in a number of different ways:

1. mass=density×volume (m=ρV). Density is a measure of mass per unit of volume, so the mass of an object can be determined by multiplying density by volume.
2. mass=force÷acceleration (m=F/a).
3. mass=weight÷gravitational acceleration (m=W/g).

What is the unit of bulk density?

The bulk density is expressed in grams per milliliter (g/mL) although the international unit is kilogram per cubic meter (1 g/mL = 1000 kg/m3) because the measurements are made using cylinders. It may also be expressed in grams per cubic centimeter (g/cm3).

What is the basic unit for density?

Density is commonly expressed in units of grams per cubic centimetre. For example, the density of water is 1 gram per cubic centimetre, and Earth’s density is 5.51 grams per cubic centimetre.

Why tapped density is measured?

Tapped density of a powder is the ratio of the mass of the powder to the volume occupied by the powder after it has been tapped for a defined period of time. The tapped density of a powder represents its random dense packing.

What is bulk unit weight?

Bulk unit weight is a measure of the amount of solid particles plus water per unit volume. Saturated unit weight is equal to the bulk density when the total voids is filled up with water.