estimation of stone-loss on network condition surveys by use of multiple texture lasers thomas...
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![Page 1: Estimation of Stone-loss on network condition surveys by use of multiple texture lasers Thomas Wahlman, thomas.wahlman@ramboll.se Peter Ekdahl, peter.ekdahl@ramboll.se](https://reader033.vdocuments.net/reader033/viewer/2022061604/5697bfe91a28abf838cb6c2a/html5/thumbnails/1.jpg)
Estimation of Stone-loss on network condition surveys by use of multiple texture lasers
Thomas Wahlman, [email protected] Ekdahl, [email protected]
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OUTLINE
•5 years of experience in Finland
•Ravelling project in Netherlands
•Homogeneity
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Indication of RavellingFinland
…detected by point lasers
![Page 4: Estimation of Stone-loss on network condition surveys by use of multiple texture lasers Thomas Wahlman, thomas.wahlman@ramboll.se Peter Ekdahl, peter.ekdahl@ramboll.se](https://reader033.vdocuments.net/reader033/viewer/2022061604/5697bfe91a28abf838cb6c2a/html5/thumbnails/4.jpg)
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Basic information of collected data
The Laser works at a frequency of 32 000 pulses per second
Speed km/h
Interval between
values30 0.3 mm50 0.4 mm70 0.6 mm90 0.8 mm
Spotsize 0.5 mm
Vertical resolution 0.1 mm
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Porous Asphalt, 16 years old
-20
-15
-10
-5
0
5
10
1100 1120 1140 1160 1180 1200 1220 1240 1260 1280 1300 1320 1340 1360 1380 1400
Dep
th
mm-data
Even Surface
Max stone size
What will the collected values look like?
Dense Asphalt, 12 years old
-20
-15
-10
-5
0
5
276.2 276.3 276.4 276.5
Depth
mm-data
What is what? Crack or Loss of stone?
![Page 6: Estimation of Stone-loss on network condition surveys by use of multiple texture lasers Thomas Wahlman, thomas.wahlman@ramboll.se Peter Ekdahl, peter.ekdahl@ramboll.se](https://reader033.vdocuments.net/reader033/viewer/2022061604/5697bfe91a28abf838cb6c2a/html5/thumbnails/6.jpg)
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Indication of Ravelling - Model
Input
Divide into homogenous sections-similar surface type
Read all RMST value of each 100mm
Look for possible ravelling in each 5m-interval
Step 1
Step 2
Output Validate result and state Ravelling/Not Ravelling per 5m
![Page 7: Estimation of Stone-loss on network condition surveys by use of multiple texture lasers Thomas Wahlman, thomas.wahlman@ramboll.se Peter Ekdahl, peter.ekdahl@ramboll.se](https://reader033.vdocuments.net/reader033/viewer/2022061604/5697bfe91a28abf838cb6c2a/html5/thumbnails/7.jpg)
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Indication of Ravelling. Change in Surface type
Dis
tan
ce
Avera
ge
Mod
e
Max
Std
dev
Ku
rtosis
Skew
ness
Ran
ge
PER
C 5
%
PER
C 9
5%
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0.9
1.0
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
1.9
2.0
3820 0.8 0.8 1.2 0.1 0.6 0.9 0.6 1 1.05 26% 32% 20% 10% 10% 2%3825 0.8 0.8 1.3 0.2 2.6 1.3 0.8 1 1.06 10% 28% 24% 20% 12% 2% 4%3830 0.9 0.9 1.3 0.2 ## 0 0.9 1 1.21 2% 8% 10% 12% 28% 18% 10% 6% 6%3835 0.9 0.8 1.5 0.2 1.5 1.1 1 1 1.32 4% 12% 18% 26% 18% 8% 6% 2% 2% 2% 2%3840 0.9 0.9 1.4 0.2 ## 0.5 0.8 1 1.22 8% 10% 16% 24% 18% 8% 8% 4% 4%3845 0.9 0.6 1.3 0.2 ## 0.3 0.9 1 1.31 4% 2% 18% 12% 18% 22% 2% 14% 2% 6%3850 0.8 0.9 1.2 0.1 1.9 0.7 0.7 1 0.95 8% 12% 36% 32% 8% 2% 2%3855 0.8 0.7 1.2 0.2 ## 0.7 0.6 1 1.17 2% 24% 18% 26% 12% 8% 8% 2%3860 0.9 0.7 1.3 0.2 ## 0.2 0.8 1 1.15 2% 8% 8% 20% 22% 16% 16% 6% 2%3865 0.9 0.9 1.5 0.2 0.9 0.7 0.9 1 1.14 8% 18% 12% 24% 18% 10% 8% 2%3870 0.9 0.9 1.5 0.2 2.0 0.6 1 1 1.17 2% 2% 6% 18% 26% 26% 8% 8% 2% 2%3875 0.8 0.7 1.3 0.2 0.4 0.5 0.8 1 1.15 4% 4% 20% 26% 22% 8% 8% 4% 4%3880 0.8 0.9 1.3 0.2 0.2 0.4 0.8 1 1.11 6% 18% 18% 32% 12% 8% 4% 2%3885 0.9 0.8 1.2 0.1 ## 0.3 0.6 1 1.07 2% 12% 34% 12% 24% 12% 2% 2%3890 0.8 0.8 1.2 0.2 ## 0.1 0.7 1 1.09 2% 16% 6% 22% 24% 16% 10% 4%3895 0.9 0.8 1.4 0.2 0.1 0.4 1 1 1.28 2% 12% 14% 26% 18% 10% 8% 8% 2%3900 0.9 0.8 1.4 0.2 0.5 0.3 0.9 1 1.12 10% 10% 14% 22% 18% 20% 4% 2%3905 0.9 1.0 1.2 0.1 ## ## 0.6 0.7 1.1 4% 8% 18% 22% 26% 20% 2%3910 0.9 0.8 1.2 0.1 0.5 0.2 0.7 0.7 1.1 4% 12% 20% 36% 12% 12% 2% 2%3915 0.8 0.9 1.2 0.2 ## 0.2 0.7 0.6 1.2 2% 8% 16% 12% 24% 24% 4% 4% 6%3920 0.8 0.7 1.3 0.2 0.3 0.5 0.8 0.6 1.2 4% 22% 10% 32% 20% 4% 4% 4%3925 1.0 0.9 1.5 0.2 ## 0.1 1.0 0.6 1.3 6% 8% 10% 14% 24% 10% 14% 6% 6% 2%3930 1.0 1.0 1.4 0.2 ## 0.0 0.8 0.7 1.3 2% 8% 14% 8% 26% 24% 6% 8% 4%3935 1.0 0.8 1.6 0.2 ## 0.3 0.9 0.7 1.3 6% 10% 12% 22% 14% 16% 14% 4% 2%3940 1.0 0.9 1.4 0.2 ## 0.1 0.8 0.7 1.4 2% 2% 10% 12% 20% 18% 14% 10% 6% 6%3945 1.0 1.0 1.6 0.2 0.5 0.7 1.0 0.8 1.3 2% 10% 24% 20% 16% 12% 10% 4% 2%3950 1.0 1.1 1.5 0.2 ## 0.2 1.0 0.6 1.4 4% 14% 12% 14% 6% 24% 6% 6% 10% 2% 2%3955 0.9 0.9 1.2 0.1 ## 0.1 0.6 0.7 1.2 2% 20% 14% 30% 20% 8% 6%3960 0.7 0.9 1.5 0.4 ## 0.2 1.2 0.3 1.3 12% 22% 10% 2% 2% 4% 20% 6% 10% 4% 6% 2% CHANGE IN SURFACE TYPE3965 0.3 0.3 0.6 0.1 2.7 1.3 0.4 0.2 0.5 2% 42% 46% 6% 4%3970 0.3 0.3 0.5 0.1 2.5 0.3 0.4 0.2 0.4 4% 36% 54% 4% 2%3975 0.3 0.3 0.4 0.0 ## 0.2 0.2 0.2 0.4 52% 46% 2%3980 0.3 0.2 0.5 0.1 0.6 0.7 0.3 0.2 0.4 60% 36% 4%3985 0.3 0.4 0.5 0.1 ## 0.0 0.3 0.2 0.4 2% 32% 54% 12%3990 0.4 0.4 0.7 0.1 0.5 0.7 0.5 0.3 0.6 22% 34% 30% 8% 4% 2%3995 0.3 0.3 0.6 0.1 0.5 0.6 0.4 0.2 0.5 2% 28% 50% 16% 4%4000 0.3 0.3 0.5 0.1 ## 0.0 0.3 0.3 0.4 2% 28% 56% 14%4005 0.3 0.3 0.6 0.1 6.2 1.7 0.4 0.2 0.4 50% 44% 4% 2%4010 0.3 0.3 0.4 0.0 0.2 0.0 0.2 0.2 0.4 4% 58% 38%4015 0.3 0.4 0.5 0.1 0.2 0.2 0.3 0.3 0.4 26% 62% 12%4020 0.3 0.3 0.5 0.1 ## 0.5 0.3 0.3 0.5 34% 44% 22%4025 0.3 0.4 0.5 0.1 ## ## 0.2 0.2 0.4 30% 54% 16%4030 0.3 0.4 0.5 0.1 1.3 0.9 0.3 0.2 0.4 40% 54% 4% 2%4035 0.3 0.3 0.6 0.1 3.2 1.4 0.4 0.3 0.5 42% 40% 16% 2%4040 0.3 0.3 0.5 0.1 0.1 0.7 0.3 0.2 0.5 42% 46% 10% 2%4045 0.4 0.4 0.6 0.1 0.9 0.4 0.4 0.3 0.5 26% 50% 22% 2%4050 0.3 0.3 0.5 0.1 0.8 0.7 0.3 0.2 0.4 44% 50% 6%4055 0.3 0.3 0.4 0.0 ## 0.0 0.2 0.2 0.4 60% 40%4060 0.3 0.3 0.5 0.1 0.5 0.6 0.3 0.2 0.4 44% 48% 6% 2%4065 0.3 0.3 0.5 0.1 ## 0.2 0.2 0.2 0.4 46% 44% 10%4070 0.3 0.3 0.5 0.1 0.7 0.6 0.3 0.2 0.4 36% 54% 8% 2%4075 0.4 0.3 0.7 0.1 3.3 1.2 0.4 0.3 0.5 22% 46% 30% 2%4080 0.4 0.3 0.7 0.1 0.9 1.2 0.5 0.3 0.6 20% 42% 22% 6% 8% 2%4085 0.4 0.4 0.7 0.1 3.3 1.3 0.5 0.3 0.5 14% 56% 22% 6% 2%4090 0.4 0.4 0.7 0.1 2.7 1.2 0.5 0.3 0.5 20% 44% 30% 4% 2%
Porous Asphalt
Dense Asphalt
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Indication of Ravelling. Make Statistics within same Surface Type (1)
Histogram RRMSTypical Distributions
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0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.8 3.0
RMST Intervall (mm)
Perc
en
tag
e
Porous AsphaltExtensive Stone loss
Dense AsphaltMinor Ravelling
Dense AsphaltExtensive ravelling
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RMS 10mväg 1102, sektion 1 (uu505b)
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0.90
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Distance
RR
MS
Right Wheel Average RMS
Middle Position Average RMS
50-percentile
90-percentile
Possible Ravelling
Moderate Ravelling
Severe Ravelling
Indication of Ravelling. Pre-test Road 1102
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Ravelling - NetherlandsBased on experience from 30 000 km survey over 6 years on the secondary road network in Netherlands
Purpose: Establish a methodology that can identify surfaces to be renewed within 2 years due to raveling.
![Page 11: Estimation of Stone-loss on network condition surveys by use of multiple texture lasers Thomas Wahlman, thomas.wahlman@ramboll.se Peter Ekdahl, peter.ekdahl@ramboll.se](https://reader033.vdocuments.net/reader033/viewer/2022061604/5697bfe91a28abf838cb6c2a/html5/thumbnails/11.jpg)
Set-up
• Information from road A348 over the years 2007, 2008, 2009, 2010 and 2011
• Measurement system: RST29, 32 kHz point lasers (3).
• Texture measured in the middle (1) and the right wheel position (2). In the years 2010 and 2011 the texture was also measured in the left wheel track.
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Methodology – frame work
• The 95-percentile RMS texture value from year 1 (new asphalt) is reference.
• The change in texture is yearly monitored through survey.
• When the 95-percentile value has increased to “X” times compared to reference, the surface will be indicated as open.
• When the 95-percentile value has increased to “Y” times to the reference, the surface will be indicated as raveled and recommended for resurfacing.
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![Page 13: Estimation of Stone-loss on network condition surveys by use of multiple texture lasers Thomas Wahlman, thomas.wahlman@ramboll.se Peter Ekdahl, peter.ekdahl@ramboll.se](https://reader033.vdocuments.net/reader033/viewer/2022061604/5697bfe91a28abf838cb6c2a/html5/thumbnails/13.jpg)
Average RMS texture
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Average value of RMS texture.
95-percentile RMS texture
Laser 1 in between wheel paths
Laser 2 in the right wheel path
The distribution is narrow which can be explained by the surface type with the dominating stone sizes of 5 mm.
![Page 14: Estimation of Stone-loss on network condition surveys by use of multiple texture lasers Thomas Wahlman, thomas.wahlman@ramboll.se Peter Ekdahl, peter.ekdahl@ramboll.se](https://reader033.vdocuments.net/reader033/viewer/2022061604/5697bfe91a28abf838cb6c2a/html5/thumbnails/14.jpg)
Change in distribution over time
Texture in the middle of the lane (laser 1) seems to be more open than the texture in the right wheel path.
The change over time is visible.
![Page 15: Estimation of Stone-loss on network condition surveys by use of multiple texture lasers Thomas Wahlman, thomas.wahlman@ramboll.se Peter Ekdahl, peter.ekdahl@ramboll.se](https://reader033.vdocuments.net/reader033/viewer/2022061604/5697bfe91a28abf838cb6c2a/html5/thumbnails/15.jpg)
Increase in RMS texture 2007-2011
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Laser 1: + 37.1%Laser 2: + 35.8%
Figure: % of 5m sections with RMS texture over the 2007 year’s 95-percentile
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Conclusions
• It seems possible to detect changes over time with RMS texture.
• It is possible to quantify this change and therefore possible to use it for indication of raveling.
• For detection of raveling the number of measurement point should be increased from 2-3 to 5 in order to cover also the edges of the lane.
• Driving pattern of the survey vehicle is essential (driver education).
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Homogeneity as quality control
![Page 18: Estimation of Stone-loss on network condition surveys by use of multiple texture lasers Thomas Wahlman, thomas.wahlman@ramboll.se Peter Ekdahl, peter.ekdahl@ramboll.se](https://reader033.vdocuments.net/reader033/viewer/2022061604/5697bfe91a28abf838cb6c2a/html5/thumbnails/18.jpg)
Examples
Poor texture/homogeneity Proper texture/homogeneity
![Page 19: Estimation of Stone-loss on network condition surveys by use of multiple texture lasers Thomas Wahlman, thomas.wahlman@ramboll.se Peter Ekdahl, peter.ekdahl@ramboll.se](https://reader033.vdocuments.net/reader033/viewer/2022061604/5697bfe91a28abf838cb6c2a/html5/thumbnails/19.jpg)
Purpose with a control of homogeneity
The quality will rise by using demands on surface structure and homogeneity
Proper structure/texture• Better friction• Influence on fuel consumption, tire wear and noice
Proper homogeneity• Increase possibility for achieving the desired service life• Reduced risk for future stone loss and separations• Reduced risk for plastic deformations
![Page 20: Estimation of Stone-loss on network condition surveys by use of multiple texture lasers Thomas Wahlman, thomas.wahlman@ramboll.se Peter Ekdahl, peter.ekdahl@ramboll.se](https://reader033.vdocuments.net/reader033/viewer/2022061604/5697bfe91a28abf838cb6c2a/html5/thumbnails/20.jpg)
Present control methods. Non-destructive
DOR (Density On Run)+ Good parameter (density)
+ Cover areas not lines
- Low speed (0.9 km/h)
- Less good repeatability on short sections
Radar (GPR)+ Parameter on variation in void content- Requires some cores samples
Thermal camera (FLIR)
Shows the asphalt temperature directly after paving
Sections with too low temperature are classified as risk sections
![Page 21: Estimation of Stone-loss on network condition surveys by use of multiple texture lasers Thomas Wahlman, thomas.wahlman@ramboll.se Peter Ekdahl, peter.ekdahl@ramboll.se](https://reader033.vdocuments.net/reader033/viewer/2022061604/5697bfe91a28abf838cb6c2a/html5/thumbnails/21.jpg)
Texture
Point lasers in three lines
Makrotexture (wave lenght 0.5 – 50.0 mm)
Parameters: MPD (Mean Profile Depth), RMS
![Page 22: Estimation of Stone-loss on network condition surveys by use of multiple texture lasers Thomas Wahlman, thomas.wahlman@ramboll.se Peter Ekdahl, peter.ekdahl@ramboll.se](https://reader033.vdocuments.net/reader033/viewer/2022061604/5697bfe91a28abf838cb6c2a/html5/thumbnails/22.jpg)
Poor quality - example
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Distans (m)
MP
D (
mm
)
MPD V
MPD M
MPD H
Separation due to high binder content on the right hand side.
Left
Mid
Right
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Objekt 2 2400-3600 meter
Mätdrag Höger
2
2.05
2.1
2.15
2.2
2.25
2.3
2.35
2.4
2400 2600 2800 3000 3200 3400 3600
Distans (m)
g/cm
3
-1.5
-1.3
-1.1
-0.9
-0.7
-0.5
-0.3
-0.1
mm
Densitet (g/cm3)
RRMS (mm)
Correlation RMS Texture/density
![Page 24: Estimation of Stone-loss on network condition surveys by use of multiple texture lasers Thomas Wahlman, thomas.wahlman@ramboll.se Peter Ekdahl, peter.ekdahl@ramboll.se](https://reader033.vdocuments.net/reader033/viewer/2022061604/5697bfe91a28abf838cb6c2a/html5/thumbnails/24.jpg)
Model
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Textur (mm)
(%)
Black
Normal distribution for the surface type
Blue
Dense surface, binder on the surface
Red
Open surface, risk for ravelling
• Collect data over 100 mm
• Calculate distribution for each 5 m
• Determine deviation from normal distribution
![Page 25: Estimation of Stone-loss on network condition surveys by use of multiple texture lasers Thomas Wahlman, thomas.wahlman@ramboll.se Peter Ekdahl, peter.ekdahl@ramboll.se](https://reader033.vdocuments.net/reader033/viewer/2022061604/5697bfe91a28abf838cb6c2a/html5/thumbnails/25.jpg)
Conclusions - homogeneity
• Surface texture can be a proper indicator of open and dense suraces (quality)
• Acceptable correlation between DOR and laser survey
• Knowledge of expected values for different surface types is needed
![Page 26: Estimation of Stone-loss on network condition surveys by use of multiple texture lasers Thomas Wahlman, thomas.wahlman@ramboll.se Peter Ekdahl, peter.ekdahl@ramboll.se](https://reader033.vdocuments.net/reader033/viewer/2022061604/5697bfe91a28abf838cb6c2a/html5/thumbnails/26.jpg)
Further work
• Determine ”master curve” for various asphalt types
• Define how deviations (grey area) shall be determined
• How large deviations can be accepted?
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0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5
Textur (mm)
(%)
![Page 27: Estimation of Stone-loss on network condition surveys by use of multiple texture lasers Thomas Wahlman, thomas.wahlman@ramboll.se Peter Ekdahl, peter.ekdahl@ramboll.se](https://reader033.vdocuments.net/reader033/viewer/2022061604/5697bfe91a28abf838cb6c2a/html5/thumbnails/27.jpg)
Conclusions
• Point lasers can be used for indication of ravelling/stone loss and homogeneity (MPD under implementation in Sweden).
• The method should be based on macro texture and statistical distributions
• Changes over time are essential to track
• Reference data for new asphalt - nice to have “mastercurves”
• At least 5 lasers should be used
• Driving pattern of the survey vehicle is essential (driver education).
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Thank you!
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