Breakwaters and closure dams appendix a2
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Transcript of Breakwaters and closure dams appendix a2
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April 12, 2012
Vermelding onderdeel organisatie
1
Quarry OperationsAppendix A2
ct5308 Breakwaters and Closure dams
H.J. Verhagen
Faculty of Civil Engineering and GeosciencesSection Hydraulic Engineering
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Types of quarries
• Production of aggregates• Production of blocks (dimension stone)
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Geological features
• Joints• Faults• Discontinuities
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joints and fractures
joints
fractures
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types of fractures
attitude of thediscontinuity
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distanced between discontinuities
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block size
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Giant Causeway, Northern Ireland
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mining plan
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mining plan
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Terraces in a quarry
Sini Vir quarry, Bulgaria
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effect of rock density and water absorptionon required rock weight
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Methods to get rock out of the mountain• Drilling and blasting
• using dynamite• using gunpowder
• Sawing
Vegard Olsen, ICS 2005, Iceland
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Blasting large blocks in a quarry
Vegard Olsen, ICS 2005, Iceland
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Drilling equipment
Sini Vir quarry, Bulgaria
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Blasting at Jebel Berri Jubail, nov 1982
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Sawing of dimension stone
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Scrap stone from a dimension stone quarry
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Loading of rejected dimension stone
Larvik, Tveidalen, Stema loading facility
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ELL: Extreme upper limitNLL: Nominal lower limitNUL: Nominal upper limitEUL: Extreme upper limit
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in 60-300 and 300-1000 kg
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production screen for 10-60 kg (falling through) and greater than 300 kg (sliding over)
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al Rakeeb sorting facility
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sorting – bar sizer
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sorting – side kick
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Splitting oversize blocks with a hydraulic 'pecker'
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Weight reduction of armour between blasting and operation in breakwater
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How big is this rock ??
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This is small rock !
Vietnam, Hue area
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Stockpile 300-1000 kg and 1-3 tons
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300 - 100 kg
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Stockpile 1-3 ton basalt
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How big is this rock ??
1 - 3 cm 1-3 tonnes
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What is dn ?
A4
dn = 22 cm
Devnya quarry, Bulgaria, fieldwork 2002
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weighing blocks individually
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analysis Devnya quarry
Mass distribution
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0.0 20.0 40.0 60.0 80.0 100.0 120.0
Mass [kg]
Perc
enta
ge b
y m
ass
light
er
M50 = 24 kgρ = 2284 kg/m3
dn50 = 22 cm
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dn log-linear scale
Distribution Dn
0%
10%20%
30%40%
50%
60%70%
80%90%
100%
0.10 1.00
Dn logarithmic scale [m]
Perc
enta
ge b
y D
n sm
alle
r
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dn on log-Gaussian scaleGaussian distribution
-2.1
-1.6
-1.1
-0.6
-0.1
0.4
0.9
1.4
1.9
0.10 1.00
Dn Gaussian scale [m]
pr(%
) - G
auss
sca
le
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New standard
• Old standard: NEN 5180 – 5188
• New standard: EN 13383• part 1: Armourstone – Specifications• part 2: Armourstone – Test Methods
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Standard conformity declaration
For armourstone use category 4
Name producerYear of markStandard numberProduct descriptionInformation on product details
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Properties description method
• When selecting an armourstone grading or property the approach is to select the appropriate category
• For example:
20DEMThe property description. In this case Micro-Devalindex
Value selected; or maximum or minimum value allowed. In this case max. value
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Categories
• An option to use No Requirement (NR) category is also possible• For example, for crushed stone, the Rounding
Index is usually not used (required for a minimum proportion of crushed or broke surfaces). So this would be RONR
• If properties are outside specific limits, the producer may declare a value• E.g. if % of armourstone pieces with L/T>3 for a
course grading is 25% (normal max. is 20%) the producer would state LT25.
• A client could buy this as an LTNR core material
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Gradings in New standard
• Course Grading45/125 – 63/180 – 90/250 – 45/180 – 90/180 mm(30/60 – – 40/100 – 50/150 – 80/200 mm)
• Light Grading5/40 – 10/60 – 40/200 – 60/300 – 5/300 kg
• Heavy Grading0.3/1 – 1/3 – 3/6 – 6/10 – 10/15 tons
Category A and B: A has some tighter control on mass distribution, but usually B is sufficient (For cover layers use category A)
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Course gradings• For general use: 45/125 63/180 90/250 mm• For wide grading: 45/180 mm• For gabion stone: 90/180 mm
Light gradings• For general use: 5 to 40 kg, 40 to 200 kg, 60 to 300 kg• For wide grading: 15 to 300 kg
Producer declared• Producer may declare other gradings, for example
HM2000/4000
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Overview of classes inEN 13383
45/125 mm63/180 mm90/250 mm45/200 mm90/180 mm5-40 kg10-60 kg40-200 kg60-300 kg15-300 kg300-1000 kg1-3 ton3-6 ton6-10 ton
CP45/125CP63/180CP90/250CP45/180CP90/180LMA 5-40LMA 10-60LMA 40-200LMA 60-300LMA 15-300HMA 300-1000HMA 1000-3000HMA 3000-6000HMA 6000-10000
rangeClass name
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Grading system
ELLextreme lower limitNLLnormal lower limitNULnormal upper limitEULextreme upper limit
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Grading description
• For course gradings:CPNLL/NUL e.g. CP90/250
• For light and heavy gradings:LMANLL/NUL
HMBNLL/NUL e.g. HMB60/300
category A or Blight of heavy grading
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Weight distribution acc. to EN13383
0
20
40
60
80
100
100 1000 10000 100000
kg
cum
ulat
ive
frac
tion 0.3-1 ton
1-3 ton3-6 ton6-10 ton10-15 ton-
Standard distributions
Mean weightcategory A Dn-distribution (adapted from EN13383)
0
20
40
60
80
100
0.3 0.8 1.3 1.8
Dn (m)
cum
ulat
ive
fract
ion
0.1-3 ton-1-3 ton-3-6 ton-6-10 ton-10-15 ton-
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Other parameters in new standard
• Shape (LT)• Crushed surface (RO)• Particle density• Resistance to breakage (CS)• Petrographic description• Dangerous substances
• proportion crushed• resistance to wear (MDE)• water absorption (WA)• freezing/thawing (FT)• salt crystallization (MS)• impurities
• dicalcium silicate disintegration• iron disintegration• steel slag disintegration (DS)• sonnenbrand (SB)
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Density requirements
• Average density of 10 pieces: > x Mg/m3
• Density of at least 36 pieces of 40 pieces tested:> x-0.10Mg/m3
• The value for x shall be declared by the producer and stated to 2 decimals places and shall not be less than 2.30.
• Note: for design use wet density:• ρwet = (1+0.0050 WA) ρdry (submerged) • ρwet = (1+0.0025 WA) ρdry (not submerged)
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Shape requirements
LTNRNo requirementNo requirement
No requirement
LTA
LTdeclared
≤5
Other value declared by the
producer
≤20
Other value declared by
the producer
≤20
Other value declared by
the producer
heavy gradingslight gradingscourse gradings
Percentage by number
Percentage by mass
categoryLT
Length to thickness ratio greater than 3
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Resistance to wear
• Micro Deval test• use MDENR for everything except cover layers• use MDE20 for most cover layers
• The test is done by placing samples in a drum, add steel balls and water, and rotate the drum for 2 hrs
• Then dry the residue and determine the percentage of abraded material
• For details see EN1097-1
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Mineral breakage
• Determine compressive strength using EN 1926• preferred category: CS80
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Durability
• Water absorption test• If WA0.5 is achieved (i.e. WA is not more than
0.5%) no further testing is needed• If not, then:
• test salt crystallisation• select category MS25
• If likely to freeze above waterline, check freeze thaw resistance
• required category FTA
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Crushed surfaces
• Only relevant when rock is NOT from a quarry, but in case river boulders, etc. are used
• So this parameter is usually not relevant
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Smaller aggregates
• Stones smaller than CP45/125 are not defined in EN13383
• Other standards:• EN12620 for the concrete industry • EN13242 (for civil engineering works and road
construction).
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From EN13242
GC Course gradingsGF Fine gradingsGNG Natural gradedGA Wide gradation
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Grading categories (EN13242)Example for grading 20/40 mm (e.g. for polymer bonded materials)