162 Lab 4

Lab Report #4 Soil Classification Using USCS & AASHTO (Abstract) The purpose of the experiment is to determine the classification of the soil sample based on the particle size, liquid limit, and plasticity index determined in previous experiments using the Unified Soil Classification System and AASHTO Classification System. These values are essential in determining characteristics and behaviour of soil in construction of engineering structures such as foundation, pavements, embankments, and roads. It has been determined that the soil is well-graded sand, SW, according to USCS while silty or clayey gravel and sand, A-2-7, according AASHTO.

Submitted by: Julius Rey D. Baniqued

Group Mates: Renz Gian Cavida Ephraim Madanguit Christian Paul Maranan Roland Mondano Jr. Marc Neil Rabin

Date Submitted: November 13, 2015

I.

Objectives 

Classify the soil sample based on the results of previous laboratory tests using USCS.



Classify the soil sample based on the results of previous laboratory tests using AASHTO Classification System.

II.

Materials 

III.

Data from previous experiment

Methodology USCS Fined grained if ≥ 50% by dry weight of specimen passes No 200 sieve or coarsed grained if ≥50% by dry weight of specimen is retained on the No 200 sieve.

Fined- Grained

Figure 1: Flowchart for Classifying Fined Grained Soils (ASTM D2487-11)

Figure 2: Flowchart for Classifying Organic Fined-Grained Soil (ASTM D2487-11) Coarsed-Grained

Figure 3: Flowchart for Classifying Coarsed-Grained Soil (ASTM D2487-11)

For AASHTO Classification System, Table 1 is used.

Table 1: Classification of soil using AASHTO Classfication System (Das, 2010) IV.

Data and Results

Sieve #

Opening, mm

Mass Retained, g

4 10 30 50 100 200 pan

4.75 2 0.6 0.355 0.15 0.075 80.35

0 646 1032.5 365.5 335.5 134 2593.85

D10 D30 D60

0.178 0.508 1.469

Plastic Limit Liquid Limit

29% 48%

Cumulative Mass Retained,g 0 646 1678.5 2044 2379.5 2513.5 0

Mass Passing, g

Percent Finer, g

2593.85 1947.85 915.35 549.85 214.35 80.35 0

100 75.0949361 35.28924186 21.19821886 8.263777782 3.097711895

19 Plasticity Index Optimum Moisture Content 22.7 % Maximum Dry Unit Weight 15.77 kN/m3

V.

Analysis and Discussion

USCS From sieve analysis, it was determined that 97% of the soil particles by dry weight are retained in the No. 200 sieve. According to ASTM D2487 Section 10.2, the soil is coarsed-grained. Since all of the coarse particles of the soil pass Sieve No. 4, according to ASTM D2487 Section 12.2, the soil is classified as sand. 3 % of the soil particles passed the 200 sieve, Cu is 8.3, and Cc is approximately 1; thus from ASTM D2487 Section 12.3.1, the soil is well-graded sand, SW. According to USCS, SW soil is very stable and pervious which requires slope protection if used in embankments and foundations. It has also good compaction characteristics and good bearing value for foundations. To control seepage, it is required to construct upstream blanket and toe drainage or wells. It does not also exhibit tendency towards high compressibility or expansion.

AASHTO Classification System Since the plasticity index of the soil is 19 > 6, the does not qualify for A-1-a, A1-b, A3, A-2-4, and A-2-5. Since liquid limit is 48% > 40, the soil does not qualify for A2-6. Since 3% < 35% passed No. 200 sieve, liquid limit is greater than 41% and plasticity index is greater than 11, the soil is classified as A-2-7. The general subgrade rating of the soil to be used beneath highway pavement is good.

VI.

Conclusion

Using USCS, the soil is classified as well-graded sand, SW. Using AASHTO Classification system, the soil is classified as silty or clayey gravel and sand, A-2-7.

VII.

References

ASTM D3282-09, Standard Practice for Classification of Soils and Soil-Aggregate Mixtures for Highway Construction Purposes, ASTM International, West Conshohocken, PA, 2009, www.astm.org ASTM D3282-09, Standard Practice for Classification of Soils for Engineering Purposes (Unified Soil Classification System), ASTM International, West Conshohocken, PA, 2011, www.astm.org

Das, B.M.. Principles of Geotechnical Engineering. Cengage Learning. 2010.

USCS. Global Security. Accessed November 13, 2015. globalsecurity.org/militaryy/libra ry/policy/army/fm/5-472/apb.pdf.