SAND. By A S M Fahad Hossain Assistant Professor Department of Civil Engineering, AUST

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1 SAND By A S M Fahad Hossain Assistant Professor Department of Civil Engineering, AUST

Definition Sand is a loose, fragmented, naturally-occurring material consisting of vary small particle (fine to medium sized particle between 0.06mm and 2.0 mm) of decomposed rocks, corals or shells.

2 Definition Sand is a loose, fragmented, naturally-occurring material consisting of vary small particle (fine to medium sized particle between 0.06mm and 2.0 mm) of decomposed rocks, corals or shells. Sand particles are formed by the breakdown of crystalline igneous and metamorphic rocks or from existing sandstone. Mineralogically, sands commonly consist of quartz, feldspers, mica and limestone.

3 Classification of Sand Classification based on source Sand is usually obtained from pits, shores, river beds and seas. There are mainly three kinds of sands in use: Pit Sand River Sand Sea Sand Pit Sand Sharp, angular, porous and free from salts. Might contain clay and other impurities. Light brown and yellowish color. Most suitable for mortar work.

Sea Sand Fine, round and polished. Worst of three verities because contain sea salts.

4 River Sand Fine, rounded and polished. Contains earthy impurities like gravels, pebbles etc. Whiter in color Smaller than pit sand. Most suitable for plaster work. Sea Sand Fine, round and polished. Worst of three verities because contain sea salts. Sea salts absorb moisture from the atmosphere causing permanent dampness and efflorescence. Also contain shells and organic matters.

5 Classification based on Size Sand is divided into five sub-categories based on size: Very fine sand (1/16mm 1/8mm) Fine sand (1/8mm 1/4mm) Medium Sand (1/4mm 1/2mm) Coarse sand (1/2mm 1mm) Very Coarse sand (1mm 2mm)

6 Classification based on Fineness Modulus Sand is divided into three categories based on Fineness Modulus Fine Sand (FM: ) Medium Sand (FM: ) Coarse Sand (FM: )

7 Size of sand based on different codes Commonly based on grain size and soil consistency, several classification systems exist: Unified Soil Classification System (USCS) (ASTM D ). American Association of State Highway and Transportation Officials (AASHTO) (ASTM D ). U.S. Department of Agriculture (USDA). Burmister Soil Identification System. Massachusetts Institute of Technology (MIT).

8 Comparative size of sand, silt and clay

9 Uses of Sand Principle component of concrete Brick manufacturing plants Sometimes mixed with paints Used in landscaping Glass manufacturing Sandbags for protection against floods Railroads Plastering and mortar Used for fill up the road & brick soling gap area

10 Desirable Properties of Sand Inert completely Grains are sharp, strong and angular Not contain hygroscopic salt Should not contain clay, silt. Free from organic matters

11 Bulking of Sand It means increase in volume. Fine aggregate increase in volume when they possess some moisture. It is due to formation of a thin film of water around sand particles. The thickness of this film goes on increasing with more and more moisture. Therefore the increase in volume of sand mass continues. This increase in volume varies 20% - 30% (volume basic) depending upto fineness of sand. The finer will undergo with greater increase in volume. After a certain % of water, the volume of sand decreasing with the further increase in water and eventually the increased volume completely vanishes, and at this moment, the volume occupied by sand becomes equal to the volume of sand. Bulking of sand effects W/C ratio and also the proportioning of aggregate.

Sieve Analysis and gradation The particle size distribution of aggregate is

Sieve analysis in a process in which an aggregate is separated into its various

determining the distribution of the quantities separated.

12 Sieve Analysis and gradation The particle size distribution of aggregate is called the grading. Sieve analysis in a process in which an aggregate is separated into its various sizes by passing it through screens of various size openings for the purpose of determining the distribution of the quantities separated. A Sieve is an apparatus- round or square in shape with square openings, identified either by the size of the opening or by a number. Sieve shaker Tray shaker Sieves

13 Commonly Used Standard Sieve Sizes (ASTM E11-09e1)

14 Particle Size Distribution Curves for sand

15 Fineness Modulus Using the sieve analysis results, a factor called the fineness modulus is often computed. This is a parameter for checking the uniformity of grading This is an index of fineness of an aggregate. The higher the FM, the coarser is the aggregate It is computed by adding the cumulative percentage of aggregate retained on each of the specific sieve s and divided the sum by 100. Sand Type FM Fine Sand Medium Sand Coarse Sand

16 Mathematical Problem Following are the results of a sieve analysis. Make the necessary calculations and draw a particle-size distribution curve. Also calculate the FM of the sand. sieve no. Mass of soil retained on each sieve (g) Pan 12

17 Solution sieve no. Opening (mm) Mass of soil retained on each sieve (g) % retained in each sieve Cumulative % retained in each sieve % Finer Pan Total 729

18 % Finer Particle Size Distribution Curve Particel Size FM = = 2.38

19 Thank You

SIEVE ANALYSIS. Introduction

SIEVE ANALYSIS. Introduction SIEVE ANALYSIS Technology of Material II TKS 4012 Prepared by zacoeb@ub.ac.id Introduction A sieve analysis (or gradation test) is a practice or procedure used (commonly used in Civil Engineering) to assess