How do you classify soil using Aashto?

How do you classify soil using Aashto?

The AASHTO system uses both grain-size distribution and Atterberg limits data to assign a group classification and a group index to the soil. The group classification ranges from A-1 (best soils) to A-8 (worst soils). Group index values near 0 indicate good soils, while values of 20 or more indicate very poor soils.

How do you classify a soil using USCS?

Unified Soil Classification System

1. Coarse grained soils: In these soils, 50% or more of the total material by weight is larger than 75 micron IS sieve size.
2. Fine grained soils: In these soils, 50% or more of the total material by weight is smaller than 75 micron IS sieve size.
3. Highly organic soils and other miscellaneous soil materials:

How do you determine soil classification?

OSHA uses a measurement called “unconfined compressive strength” to classify each type of soil. This is the amount of pressure that will cause the soil to collapse. This value is usually reported in units of tons per square foot. Soils can be classified as Type A, Type B, or Type C.

What is Soil Mechanics & classification of soil?

In general, soils may be classified as coarse-grained (cohesionless) and fine-grained (cohesive) soil. The both coarse-grained and fine-grained soils can be further sub-divided based on their grain size. According to Indian Standard Soil Classification System (ISSCS), soil with particle size > 300 mm is called Boulder.

Can water content be more than 100?

In soil Mechanics Water Content (w) = Weight of water/weight of Soil. Water Contains shows us in what percentage water is present in whole soil sample. soils moisture content can range from 0 to 300 percent. Water contain can’t be greater than 100% cause it’s impossible to get obtain marks greater than the total marks.

Can water content be more than 1?

Values of Sw can range from 0 (dry) to 1 (saturated). In reality, Sw never reaches 0 or 1 – these are idealizations for engineering use.

What is difference between moisture content and water content?

Usually water content refers to wet basis while moisture content refers to a dry basis. So basically water content = (total weight – dry weight)/total weight and moisture content = (total weight – dry weight)/dry weight.

What is MDD test of soil?

Compaction testing in the laboratory is conducted for various reasons, but generally is it to determine for a pavement or earthwork material sample the Optimum Moisture Content (OMC) and Maximum Dry Density (MDD) or Maximum Wet Density (MWD). These tests are generally referred to as Proctor tests.

What is CBR of soil?

The California Bearing Ratio (CBR) test is a penetration test used to evaluate the subgrade strength of roads and pavements. The CBR test was developed by the California Division of Highways to classify and evaluate soil-sub grade and base coarse materials for flexible pavements.

How do you calculate OMC and MDD?

To calculate the amount of liquid required per m3 to achieve OMC, multiply the answer in #5 (4grm) by 9000. Or, simply by a factor of 9. (4grm x 9 = 36ltr of liquid) This will give you the total amount liquid liters (36ltr) to achieve OMC.

Can compaction be more than 100?

In case the compaction test results indicate values exceeding 100%, it only means that the in-situ compaction is more than that being carried out in laboratories which is treated as the basic criterion for satisfactory degree of soil compaction.

Why Proctor test is done?

Compaction test of soil is carried out using Proctor’s test to understand compaction characteristics of different soils with change in moisture content. Compaction of soil is the optimal moisture content at which a given soil type becomes most dense and achieve its maximum dry density by removal of air voids.

How do you achieve 98% compaction?

To obtain 98% compaction, the soil moisture must be within +/- 1% of optimum moisture. Considering that the in-place moisture content of soil can vary from less than 1% to more than 100%, controlling the in-place moisture within such tight constraints is sometimes difficult.

What is a Proctor curve?

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. The graphical relationship of the dry density to moisture content is then plotted to establish the compaction curve.

What is maximum dry density?

The dry density obtained by the compaction of soil at its optimum moisture content.

How do you test for compaction?

The best way to test is to probe the soil with a compaction tester to a depth of 36″ to 48″. The testing rod should move down through the soil with steady, even pressure, Hard, compacted soils resist penetration with the rod. Often penetration abruptly stops at a fairly uniform depth across a field or landscape area.

How many types of compaction tests are there?

two different

What is compaction ratio?

The amount this volume is reduced by is called the compaction ratio. 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.

What are the method of compaction?

The method of compaction is primarily of four types such as kneading, static, dynamic or impact and vibratory compaction.

What are the four common types of compaction equipment?

The various types of compaction equipment used in building projects include:

• Smooth Wheeled Rollers: It is an important equipment for compaction.
• Sheepsfoot Rollers: Sheepsfoot rollers also known as a tamping roller.
• Pneumatic Roller:
• Vibratory Roller:
• Rammers:
• Vibratory Plate Compactor:

How would you select the type of roller to be used?

To select a particular type of roller depends on the job size, the type of material, lift thickness and the congestion in the work site. In case of a small sized projects, the soil material is usually found to be spread.

Which field method is recommended for the compaction of cohesive soil?

In case of moderately cohesive soils, compaction can be done in layers to get best possible results. The compaction is done by roller. For silts of low plasticity, pneumatic rollers are preferred. In case of soils with moderate plasticity, sheepsfoot rollers are preferred.

How compaction of soil is controlled in field?

Ways of preventing compaction include: Avoid the use of heavy machineries or equipment on wet soils as the soil in this condition is vulnerable to compaction. Enrich the soil with organic matter. Organic matter in soils improves soil structure and aggregation.

Is code for MDD of soil?

of the specimen shall be determined as in IS : 2720 ( Par: 2 )- 1973*. 5.1. 4 The remainder of the soil specimen shall be broken up, rubbed through the 19-mm IS test sieve, and then mixed with the remainder of the original sample.

How do you calculate compaction in a field?

Determine the degree of compaction by comparing with MDD (Maximum Dry Density)

1. Maximum dry density MDD obtained by Proctor Test = 1766.31 kg/m3
2. Degree of Compaction (DOC) = (dry density of soil / MDD) x 100 = (1682.2 / 1766.31) x 100.