Experiment 3 Compaction According ASTM D 155702 Soil

Content u u u u Definition of Compaction Effective of compaction Type of Compaction

What is compaction? A simple ground improvement technique, where the soil is densified through

Compaction Effect Air Water Solid Loose soil Soil Mechanics Lab CE 350 Compacted soil

Type of Test Weight of Hammer Height of Hammer Number of Blows Number of

Objective u Determine the maximum dry unit weight. u Determine the optimum water content.

REQUIRED APPARATUS Compaction mold with plate and collar u Automatic Compactor Machine u Moisture

REQUIRED MEASUREMENTS u Volume of compaction mold, Vm. u Moisture content of soil specimen,

Dry Density Determination Mold No. Weight of mold (gm) Weight of mold + soil

Dry density ( d) Compaction Curve Direct Goal u u d, max u optimum

Compaction Curve What happens to the relative quantities of the three phases with addition

Dry density ( d) Results Zero air void curve (S=100%) Modified w 12 14

Compaction Curves for Different Types of Soil One peak Double peak (Well Graded Sand)

Application Filling after excavation u Filling behind retaining wall u Road base and sub

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Experiment # 3 Compaction According ASTM D 1557/02 Soil Mechanics Lab CE 350 Compaction 1

Content u u u u Definition of Compaction Effective of compaction Type of Compaction Objective Data and Calculation Compaction Curves Application Soil Mechanics Lab CE 350 Compaction 2

What is compaction? A simple ground improvement technique, where the soil is densified through external compactive effort. Compactive effort + water = Soil Mechanics Lab CE 350 Compaction 3

Compaction Effect Air Water Solid Loose soil Soil Mechanics Lab CE 350 Compacted soil Compaction 4

Type of Test Weight of Hammer Height of Hammer Number of Blows Number of Layers Volume of Mold Standard Proctor Modified Proctor 5. 5 Ib 10 Ib 1 ft 1. 5 ft 25 25 3 5 1/30 ft 3 (944 cm 3) Energy= (Weight of Hammer* Height of Hammer*Number of Blows*Number of Layers) Soil Mechanics Lab CE 350 5 Compaction Volume of Mold

Objective u Determine the maximum dry unit weight. u Determine the optimum water content. Soil Mechanics Lab CE 350 Compaction 6

REQUIRED APPARATUS Compaction mold with plate and collar u Automatic Compactor Machine u Moisture tins. u Steel straight edge u Mixing pan. u Sample extruder. u Trimming knife u Drying oven u Sieve No. 4. u Balance, sensitive to 0. 01 gm. u Soil Mechanics Lab CE 350 Compaction 7

REQUIRED MEASUREMENTS u Volume of compaction mold, Vm. u Moisture content of soil specimen, w. u Weight of mold and compacted soil specimen, Wms u Weight of clean empty mold, Wm. Soil Mechanics Lab CE 350 Compaction 8

Dry Density Determination Mold No. Weight of mold (gm) Weight of mold + soil (gm) Weight of soil (gm) Moist unit weight (gm/cm 3) Dry unit weight (gm/cm 3) Water Content Determination Can no. Weight of can + soil Weight of can + dry soil Weight of water (gm) Weight of dry soil (gm) Water content (%) Avg. water content 1 2 3 4 Soil Mechanics Lab CE 350 Compaction 9

Dry density ( d) Compaction Curve Direct Goal u u d, max u optimum Soil Mechanics Lab CE water content 350 Increase shear strength Reduce settlement Reduce permeability Water content Compaction 10

Compaction Curve What happens to the relative quantities of the three phases with addition of water? air Dry density ( d) water soil difficult to expel all air lowest void ratio and highest dry density at optimum w Soil Mechanics Lab CE 350 Compaction Water content 11

Dry density ( d) Results Zero air void curve (S=100%) Modified w 12 14 16 18 d … … Standard Soil Mechanics Lab CE 350 Water content Compaction 12

Compaction Curves for Different Types of Soil One peak Double peak (Well Graded Sand) (Poorly Graded Sand) Odd Shape One & half peak (Silt OR Poorly Graded Sand with Silt) Soil Mechanics Lab CE 350 (Clay) Compaction 13

Application Filling after excavation u Filling behind retaining wall u Road base and sub base material u Soil Structure i. e. earth dam u Soil Mechanics Lab CE 350 Compaction 14