Laboratory and Field testing

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Laboratory and Field testing

• Durham University

João Mendes
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Summary

• Sample preparation
• Compaction
• Wetting and drying procedure
• Field instrumentalization

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Laboratory testing

• Compact samples
• Measure initial suction
• Wet/dry to required water content and measure new
  suction
• Consolidate
• Shear

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Bionics Soil - Sample Preparation
Air drying to atmosphere
20mm Sieve
2.80mm Sieve
Oven drying
Preparation of 4 bags with 1000g of soil each
Addition of water to the desired water content
Period of equalisation of 24 hrs
Compaction
Determination of final water content
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Bionics Soil - Sample Preparation

• Water content determination
• - 6 layers (1 to 6)
• - 3 zones
• - outer ring
• - middle ring
• - core or center

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Bionics Soil - Sample Preparation
Initial water content 22 Final
average21.7 Sieved material 2.80mm
Note positon axis - 1 correspond to the outer
ring 2 for the middle ring and 3 represents the
core of the layer
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Bionics Soil - Compaction

• British Standard procedure BS-1377
• Light compaction hammer (2.5 kg)
• Heavy compaction hammer (4.5 kg)
• Differing
• Height of 200 mm
• Number of layers 6 instead of 3
• Total number of blows 276 instead of 273
• Sieve 2.80 mm

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Bionics Soil - Compaction

• Compaction curves
• BS light compaction (BSL 100)
• BS heavy compaction (BSH 100)
• BS light compaction 200mm (BSL 200)
• BS heavy compaction 200mm (BSH 200)
• BS light compaction 200mm recycled (BSL 200 R)
• BS light compaction 200mm/2.80mm sieve (BSL 200
  S)
• BS light compaction 200mm/2.80mm sieve recycled
  (BSL 200 SR)

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Bionics Soil - Compaction
Sr 100
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Bionics Soil Wetting procedure

• Samples compacted with the proctor light hammer
• Humidification provided by the humidification
  chamber
• Equalisation for two weeks or more
• Wraped in cling film
• Final water content determination

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Bionics Soil Wetting procedure

• Humidification chamber
• Reservoir with distiled water
• 2 mini foggers

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Bionics Soil Wetting procedure
(Test 1)
(Test 3)
(Test 2)
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Bionics Soil Wetting procedure
Original material Equalisation time 2
weeks Initial water content 15 Final
average19.8 Horizontal variation 1 Vertical
variation 3.5

• Test 1

Note in the positon axis - 1 correspond to the
outer ring 2 for the middle ring and 3
represents the core of the sample
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Bionics Soil Wetting procedure
Sieve material Equalisation time 2
weeks Initial water content 15 Final
average19.1 Horizontal variation
1.5 Vertical variation 2.5

• Test 2

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Bionics Soil Wetting procedure
Original material Equalisation time 2
weeks Initial water content 15 Final
average19.1 Horizontal variation
0.5 Vertical variation 1

• Test 3

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Bionics Soil - Drying Procedure

• Samples compacted with the proctor light hammer
• Air drying to atmosphere until it reaches desired
  water content (usually 5-7 days)
• Equalisation
• Wraped in cling film
• Final water content determination

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Bionics Soil - Drying Procedure
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Bionics Soil - Drying Procedure
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Field Instrumentalization

• Field equipment
• 2 borehole probe locators with 5 probes each
• 10 tensiometers
• 10 plugs
• Logger
• Computer
• Power source
• 100 meters cable
• Saturation vessel.

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Field Instrumentalization

• Not ready
• 2nd borehole probe locator
• Logger
• Tensiometers (saturation and calibration
  undergoing).

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Field Instrumentalization

• Suction Measurement of the bentonite mixture

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Field Instrumentalization
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Field Instrumentalization
Bentonite mix
Soil
Soil
Bentonite mix
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Field Instrumentalization

• Wetting test