Atterberg Limits and N / a N / a Plasticity Essay example

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CEE 749 – Advanced Geotechnical Testing
South Dakota State University
Department of Civil and Environmental Engineering
Advanced Geotechnical Testing
MEMORANDUM
To: Dr. Allen Jones Date: 02/12/2015
From: Abdullah Boudaqa Lab Partners: Individual work
Subject: Atterberg limits

Sample Description:
Sample No.
Soil Name
Visual Classification
USCS Classification
AASHTO Classification

2
Nora Moody
Clay
Lean Clay with Sand (CL)
Lean-Clay with Sand (CL)
A-7-6(14)

3
Bentonite
Fat Clay (CH)
Fat Clay (CH)
A-7-5(378)

6
Watermelon Sand
Poorly-Graded Sand (SP) Poorly-Graded Sand With Clay (SP-SM) A-3(0)

7
N/A
Well-Graded Sand (SW)
Poorly-Graded Sand (SP)
A-1-a(0)

Four different soil samples were provided in this lab. Each soil sample was descried based on three different classification systems; visual classification, Unified Soil Classification System (USCS), and AASHTO for soil classification. All soil samples were received in a dry and disturbed condition. Table 1 shows the classification of each soil sample based on different classification systems. See Table A-1 IN Appendix A for detailed visual classifications.

Table 1: Soil Sample Classification Based on Different Classification Systems

Source: Each soil sample has been provided in a five gallon bucket with very low moisture content. No further information was provided.

Results:
The main purpose of this lab is to determine the Atterberg limits for different soil samples (liquid limit, plastic limit, and plasticity index etc.). The first step of this lab was to predict the Atterberg limits during the visual classification. Table 2 shows the estimated Atterberg limits for each sample based on the lab observation. The second step of this lab was to determine the Atterberg limits by conducting scientific tests following American Society of Testing Materials ASTM. Table 2 shows the determined Atterberg limits for each sample based on scientific tests. The plastic limits for soil sample no.6 and sample No.7 could not be determined due to the crumbling of the soil threads before they reach an eighth inch diameter at any water content. The liquid limit for soil No.6 could not be obtained since the required number of blows to close the groove in Casagrande test did not reach 25 blows at any water content (the sample was either too wet or too brittle to behave as a liquid). See Appendix A and B for raw data sheets.

Table 2: The Estimated Atterberg Limits for Each Sample Based on the Lab Observation
Sample No.
Soil Name
Plastic Limit
Liquid Limit
Plasticity Index

2
Nora Moody Clay
20
40
20

3
Bentonite
75
400
325

6
Watermelon Sand
NON PLASTIC
25
N/A

7
N/A
NON PLASTIC
25
N/A

Table 3: The Determined Atterberg Limits for Each Sample Based on Scientific Tests
Sample No.
Soil Name
Plastic Limit
Liquid Limit
Plasticity Index
Flow Index
Toughness Index
2
Nora Moody Clay
23
42
19
-0.262
-73
3
Bentonite
71
407
336
-2.25
-149
6
Watermellon Sand
NON PLASTIC
LL could not be determined
N/A
N/A
N/A
7
N/A
NON PLASTIC
21
N/A
0.072
N/A

Test Procedure:
Refer to ASTM D 222 - 63 – Standard Test Method for Particle-Size Analysis of Soils

Refer to ASTM D 2487 – 00 – Standard Test Methods for Amount of Material in Soils Finer than the No. 200 (75-um)

Refer to ASTM D3282- Standard Practice for Classification of Soils and Soil-Aggregate Mixtures for Highway Construction Purposes Refer to ASTM D4318- Standard Test Methods for Liquid Limit, Plastic Limit, and Plasticity Index of Soils.

Remarks:
The first step of performing Atterberg limits tests is to calibrate the apparatus that will be used in those tests. There are number of apparatus in the lab that do not meet the ASTM standard requirement. The devices that have been used to obtain the results in the report were calibrated and passed the ASTM