Post on 02-Apr-2015
1
Bicyclist Ride Quality: Preliminary Results
Hui Li, Ph.D.
UC Pavement Research Center (UCPRC)
University of California, Davis & Berkeley
Nov 12th, 2013
SLO County Bike Advisory Committee Meeting
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Outline
Macrotexture Measurement
Bicycle Vibration Measurement
Survey on Bicyclist Ride Quality
Additional Survey
Remedial Treatment on SLO-1
Remarks
3
Macrotexture Measurement
Laser Texture Scanner (LTS)Spot block measurement with need for traffic closure
Inertial Profiler (IP)Continuous linear measurement without need for traffic closure
Mean Profile Depth (MPD)Unit: mm or in
4
MPD (example): Continuous measurement w/ IP
85 90 95 100
0123456
Postmile (km)
MP
Dm
m
53.1 56.2 59.4 62.5Postmile (mile)
00.040.080.120.160.20.24
MPD
(in)
SLO1_51.3-62.5_NB_SHLDR
100 105 110 115
0123456
Postmile (km)
MP
Dm
m
62.5 65.6 68.8 71.9Postmile (mile)
00.040.080.120.160.20.24
MPD
(in)
SLO1_62.5-74.3_NB_SHLDR
100 105 110 115
0123456
Postmile (km)
MP
Dm
m
62.5 65.6 68.8 71.9
Postmile (mile)
00.040.080.120.160.20.24
MPD
(in)
SLO1_74.3-62.5_SB_SHLDR
85 90 95 100
0123456
Postmile (km)
MP
Dm
m
53.1 56.2 59.4 62.5Postmile (mile)
00.040.080.120.160.20.24
MPD
(in)
SLO1_62.5-51.3_SB_SHLDR
85 90 95 100
0123456
Postmile (km)
MP
Dm
m
53.1 56.2 59.4 62.5Postmile (mile)
00.040.080.120.160.20.24
MPD
(in)
SLO1_51.3-62.5NB_WP
100 105 110 115
0123456
Postmile (km)
MP
Dm
m
62.5 65.6 68.8 71.9Postmile (mile)
00.040.080.120.160.20.24
MPD
(in)
SLO1_62.5-74.3_NB_WP
100 105 110 115
0123456
Postmile (km)
MP
Dm
m
62.5 65.6 68.8 71.9
Postmile (mile)
00.040.080.120.160.20.24
MPD
(in)
SLO1_74.3-62.5_SB_WP
85 90 95 100
0123456
Postmile (km)
MP
Dm
m
53.1 56.2 59.4 62.5Postmile (mile)
00.040.080.120.160.20.24
MPD
(in)
SLO1_62.5-51.3_SB_WP
HMA
HMA
Bridge
Bridge
51 6 2 5 3 4 7 16 8 15 9 14 10 13 11 12 17 18 19 20 21 22 23
0
1
2
3
4
Survey Section #
MP
D (
mm
)1, 6 = 5/16 in PME Seal Coat2, 5 = Modified Binder Seal Coat - Modified gradation3, 4 = Modified Binder Seal Coat - Utilizing steel roller7, 16 = Cinder Seal8, 15 = Microsurfacing9, 14 = 1/4 in PME Seal Coat - 2nd application of a double chip seal10, 13 = Sand Seal11, 12 = Slurry Seal17, 18 = Old HMA Overlay on Mon-19819, 20 = New Chip Seal on Mon-198 (Control)21-23 = New Chip Seal on SLO-1 (Control)
Sand Seal
Chip SealOn Mon-198
Chip SealOn SLO-1
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Bicycle Vibration Measurement
Accelerometers (solid red circles) GPS unit (dot blue circle)
71 6 2 5 3 4 7 16 8 15 9 14 10 13 11 12 17 18 19 20 21 22 23
0.0
0.2
0.4
0.6
0.8
1.0
1.2
Survey Section #
Bic
yc
le V
ibra
tio
n A
z (g
)1, 6 : 5/16 in PME Seal Coat2, 5 : Modified Binder Seal Coat - Modified gradation3, 4 : Modified Binder Seal Coat - Utilizing steel roller7, 16 : Cinder Seal8, 15 : Microsurfacing9, 14 : 1/4 in PME Seal Coat - 2nd application of a double chip seal10, 13 : Sand Seal11, 12 : Slurry Seal17, 18 : Old HMA Overlay on Mon-19819, 20 : New Chip Seal on Mon-198 (Control)21-23 : New Chip Seal on SLO-1 (Control)
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Bicyclist SurveyAcceptability (0 = Unacceptable; 1 =
Acceptable): average rate of acceptability or percentage of riders rating pavements as “Acceptable”.
Ride Quality: 1 to 5, with 1 = Poor and 5 = Excellent.
Other background information with potential correlations.
GroupSection
#
Rider
#
Mon-198 16 24
SLO-1 3 11
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MPD(mm)
0.4 0.6 0.8 1.0
0.90 0 . 0 1
0.0 0.2 0.4 0.6 0.8 1.0
-0.850.5
1.0
1.5
2.0
2.5
3.0
-0.88
0.4
0.5
0.6
0.7
0.8
0.9
1.0
Vibration Az(g)
0 . 0 0 -0.94 -0.96
Speed(mph)
-0.23
11
12
13
14
15
16
17
-0.13
0.0
0.2
0.4
0.6
0.8
1.0
Acceptability(rate) 0.95
0.5 1.0 1.5 2.0 2.5 3.0 11 12 13 14 15 16 17 1.5 2.0 2.5 3.0 3.5 4.0
1.5
2.0
2.5
3.0
3.5
4.0
Ride Quality(level 1 - 5)
Scatterplot Matrix (Mon-198 + SLO-1)
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Remedial Treatment on SLO-1Preliminary measurement just after construction of short test sections of sand seal
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Additional Surveys
GroupSectio
n #
Ride
r #
Mon-198 16 24
SLO-1 3 11
Davis 4 6
Santa
Rosa6 26
Tahoe 4 16
Chico
Velo5 8
Alto Velo 4 16
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MPD(mm)
2 4 6 8
-0.18 0.48
10 15 20 25 30
0.11 -0.70
0.0 0.2 0.4 0.6 0.8 1.0
0.51.01.52.02.53.03.5
-0.68
2
4
6
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IRI(m/km) 0.56 0 . 0 2 -0.28 -0.30
Vibration Az(g) 0.36 -0.69
0.20.40.60.81.01.21.4
-0.74
10
15
20
25
30
Speed(mph)
- 0 . 0 2 -0.17
Ride Quality(level 1 - 5)
1.01.52.02.53.03.54.04.5
0.92
0.5 1.0 1.5 2.0 2.5 3.0 3.5
0.0
0.2
0.4
0.6
0.8
1.0
0.2 0.6 1.0 1.4 1.0 2.0 3.0 4.0
Acceptability(rate 0 - 1)
Scatterplot Matrix (All Groups)
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RemarksFrom preliminary results, 80% riders rate pavements
with 2.0 mm MPD as acceptable; 50% for 2.5 mm.Sand seal reduces the macrotexture (MPD) of the chip
seal on SLO-1. The final reduction will be measured after completing construction and opening to traffic for a while.
Beside MPD (macrotexture), IRI (roughness/unevenness) may also influence the bicyclist ride quality. Unmaintained pavement develops greater IRI due to cracking, rutting.
Need to consider the balances & tradeoffs:Ride quality (smoothness) and ride safety (skidding
resistance)Vehicle users and bicycle users (different needs)Performance and cost
14http://www.ucprc.ucdavis.edu/PDF/UCPRC-TM-201
3-07.pdf
Final report, including results of additional survey sections, to be completed in December, publish in February.
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Thanks!Q&A
John Harvey, jtharvey@ucdavis.eduHui Li, hili@ucdavis.edu