Lab Report
CE121: Construction Materials Laboratory Report No. 1
Particle Size Distribution
Van Joseph E. Casalme
2010-14928, BS Civil Engineering
Institute of Civil Engineering, College of Engineering
University of the Philippines Diliman, Diliman Quezon City 1101
Submitted to: Engr. Christian R. Orozco
ABSTRACT
This test (ASTM C136-06) determines the grading of materials being used as aggregates using two parameters (coefficient of uniformity and gradation) from particle-size distribution curve. Sieve analysis consists of shaking the sample through a set of sieves that have progressively smaller openings. To conduct a sieve analysis, samples are oven dried for at least 24 hours. The soil is placed and shaken through a stack of sieves with openings of decreasing size from top to bottom. The mass of particles retained in each sieve is determined. Results showed that the particle–size distribution curve of coarse aggregate is characterized by a steep curve. This means the coarse aggregate is poorly or uniformly graded with small variation in size. Particle-size distribution curve of fine aggregate is characterized by an S-curve. It is well graded and has a gradation of particle size that spans evenly the size from coarsest to finest. Conclusions drawn from the interpretation of the particle-size distribution curve is supported by computed coefficients of uniformity and gradation which is 6.79 and 1.03 for (well graded) fine aggregates, and 1.57 and 1.05 for (poorly graded) coarse aggregate.
Significance of the Experiment
Particle size analysis is important because it determines the soil gradation, which is an indicator of other soil properties such as compressibility, shear strength, and hydraulic conductivity. A poorly graded soil will have better drainage because of more void spaces. A well graded soil is able to be compacted more than a poorly graded soil.
Standard Reference
ASTM C136-06 - Standard Test Method for Sieve Analysis
Particle Size Distribution
Van Joseph E. Casalme
2010-14928, BS Civil Engineering
Institute of Civil Engineering, College of Engineering
University of the Philippines Diliman, Diliman Quezon City 1101
Submitted to: Engr. Christian R. Orozco
ABSTRACT
This test (ASTM C136-06) determines the grading of materials being used as aggregates using two parameters (coefficient of uniformity and gradation) from particle-size distribution curve. Sieve analysis consists of shaking the sample through a set of sieves that have progressively smaller openings. To conduct a sieve analysis, samples are oven dried for at least 24 hours. The soil is placed and shaken through a stack of sieves with openings of decreasing size from top to bottom. The mass of particles retained in each sieve is determined. Results showed that the particle–size distribution curve of coarse aggregate is characterized by a steep curve. This means the coarse aggregate is poorly or uniformly graded with small variation in size. Particle-size distribution curve of fine aggregate is characterized by an S-curve. It is well graded and has a gradation of particle size that spans evenly the size from coarsest to finest. Conclusions drawn from the interpretation of the particle-size distribution curve is supported by computed coefficients of uniformity and gradation which is 6.79 and 1.03 for (well graded) fine aggregates, and 1.57 and 1.05 for (poorly graded) coarse aggregate.
Significance of the Experiment
Particle size analysis is important because it determines the soil gradation, which is an indicator of other soil properties such as compressibility, shear strength, and hydraulic conductivity. A poorly graded soil will have better drainage because of more void spaces. A well graded soil is able to be compacted more than a poorly graded soil.
Standard Reference
ASTM C136-06 - Standard Test Method for Sieve Analysis
References: : Building Research Institute. "Concrete Technology." n.d. Breins Engineering. July 4 2013 . Das, Braja. Fundamentals of Geotechnical Engineering. California, USA: Brooks/Cole Thompson Learning, 2000. "Grading of Aggregates." n.d. . Office of Water Programs. "Uniformity Coefficient." 2012. Sacramento State Office of Water Programs. 3 July 2013 . _______________________________________ 1reference consulted aside from ASTM manual