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Life-cycle performance determination of concrete
bridge decks with exposure to aggressive
environment via a new risk rating method
Ning Xie1, Xianming Shi2
1. Montana State University
2. Washington State University
Merits:
transportation safety and efficiency in cold regions.
Costs:
Approximately $2.3 billion annually to keep highways free of snow and ice at
national level, and about 20 million tons of road salt is applied.
Negative effects:
Environment, service lives, and maintenance costs of the concrete infrastructures.
Add at least $5 billion each year.
The corrosive effect of deicing chemicals on embedded steel reinforcement is well
known;
however, it is still unclear how the deicing chemicals have effects on the
deterioration of the concrete in the fields.
BACKGROKUND
MECHANISMS
Physical: Freeze/thaw damage.
Chemical: Chemical reactions between the deicing chemicals and the cement
concrete to form new products.
Corrosion inhibitors and other additives in deicers did NOT show
significant benefit in inhibiting the strength or chemical changes of
concrete induced by cations and/or anions in deicers.
Bridge
No.
Splitting
tensile
strength Evaluation by
ODOT
Evaluation by
CSIL
Relat
Dens
Para,
(q-qc)/q
Gas
Perm
Traffic
(ADT)
Truck
Percent
YEAR
BUILT
F/T
cycles
(over 7
Yrs)
Deicer
Usage
(gln/ln-
mi-FY)
09268S 848±202 5-FAIR 86% - 87% 0.32 61.6 56700 10 1972 88 105.37
00576 648±9 4-POOR 52% - 57% 0.32 61.6 6450 8 1927 226 129.6
08958F 739±146 6-SATISFACTORY 86% - 87% 0.46 28.4 7790 11 1973 102 366.9
08682 606±47 4-POOR 47% - 48% 0.47 27.3 14200 15 1962 389 2662.56
18940 422±31 7-GOOD 61% - 67% 0.34 52.6 20600 10 2002 151 2091.09
16440 570±55 7-GOOD 44% - 45% 0.39 39.1 8332 33 1985 590 2057.78
19681 664±255 7-GOOD 65% - 68% 0.6 16.8 5454 42 2003 884 3006.02
18525 523±13
8 6-SATISFACTORY
84% - 85%
0.41 35.9 13500 3 2002 353 550.81
19268 876±11 7-GOOD - 0.8 9.5 3100 11 2005 511 2525.06
16358 589±106 7-GOOD 72% - 75% 0.29 73.5 12801 10 1986 88 1023.69
16534 465 6-SATISFACTORY 33% - 41% 0.26 86.5 9793 16 1985 88 3784.49
16844 809 6-SATISFACTORY 83% - 85% 0.39 39.4 29440 7 1990 224 165.87
NOTE: ODOT CASE
The splitting tensile strength as a function of deicer usage
The microhardness of concrete specimens from two ODOT bridge decks,
exposed to a) 105 and b) 2663 gln/ln-mi/FY, respectively
Lab concrete samples experienced 10 F/T cycles in MgCl2 and NaCl solutions
ISSAEST, Fairbanks, AK, USA, August 2-5, 2015
where a, b, g represent the weights of F/T cycles, fatigue stresses, and chemical
attacking, which are about 0.5-0.6, 0.1-0.2, and 0.3-0.4, respectively. The sum of a and
g is a constant, which means the higher quantity of deicers, the less F/T cycles.
SEM images of the ODOT Bridge deck -- 16844
Bridge
No.
Splitting
tensile
strength Evaluation by
ODOT
Evaluation by
CSIL
Relat
Dens
Para,
(q-qc)/q
Gas
Perm
Traffic
(ADT)
Truck
Percent
YEAR
BUILT
F/T
cycles
(over 7
Yrs)
Deicer
Usage
(gln/ln-
mi-FY)
09268S 848±202 5-FAIR 86% - 87% 0.32 61.6 56700 10 1972 88 105.37
00576 648±9 4-POOR 52% - 57% 0.32 61.6 6450 8 1927 226 129.6
08958F 739±146 6-SATISFACTORY 86% - 87% 0.46 28.4 7790 11 1973 102 366.9
08682 606±47 4-POOR 47% - 48% 0.47 27.3 14200 15 1962 389 2662.56
18940 422±31 7-GOOD 61% - 67% 0.34 52.6 20600 10 2002 151 2091.09
16440 570±55 7-GOOD 44% - 45% 0.39 39.1 8332 33 1985 590 2057.78
19681 664±255 7-GOOD 65% - 68% 0.6 16.8 5454 42 2003 884 3006.02
18525 523±13
8 6-SATISFACTORY
84% - 85%
0.41 35.9 13500 3 2002 353 550.81
19268 876±11 7-GOOD - 0.8 9.5 3100 11 2005 511 2525.06
16358 589±106 7-GOOD 72% - 75% 0.29 73.5 12801 10 1986 88 1023.69
16534 465 6-SATISFACTORY 33% - 41% 0.26 86.5 9793 16 1985 88 3784.49
16844 809 6-SATISFACTORY 83% - 85% 0.39 39.4 29440 7 1990 224 165.87
NOTE: ODOT CASE
SEM images of the ODOT Bridge deck -- 08682
SEM images of the ODOT Bridge deck -- 08682
Bridge
No.
Splitting
tensile
strength Evaluation by
ODOT
Evaluation by
CSIL
Relat
Dens
Para,
(q-qc)/q
Gas
Perm
Traffic
(ADT)
Truck
Percent
YEAR
BUILT
F/T
cycles
(over 7
Yrs)
Deicer
Usage
(gln/ln-
mi-FY)
09268S 848±202 5-FAIR 86% - 87% 0.32 61.6 56700 10 1972 88 105.37
00576 648±9 4-POOR 52% - 57% 0.32 61.6 6450 8 1927 226 129.6
08958F 739±146 6-SATISFACTORY 86% - 87% 0.46 28.4 7790 11 1973 102 366.9
08682 606±47 4-POOR 47% - 48% 0.47 27.3 14200 15 1962 389 2662.56
18940 422±31 7-GOOD 61% - 67% 0.34 52.6 20600 10 2002 151 2091.09
16440 570±55 7-GOOD 44% - 45% 0.39 39.1 8332 33 1985 590 2057.78
19681 664±255 7-GOOD 65% - 68% 0.6 16.8 5454 42 2003 884 3006.02
18525 523±13
8 6-SATISFACTORY
84% - 85%
0.41 35.9 13500 3 2002 353 550.81
19268 876±11 7-GOOD - 0.8 9.5 3100 11 2005 511 2525.06
16358 589±106 7-GOOD 72% - 75% 0.29 73.5 12801 10 1986 88 1023.69
16534 465 6-SATISFACTORY 33% - 41% 0.26 86.5 9793 16 1985 88 3784.49
16844 809 6-SATISFACTORY 83% - 85% 0.39 39.4 29440 7 1990 224 165.87
NOTE: ODOT CASE
SEM images of the ODOT Bridge deck -- 16534
Bridge
No.
Splitting
tensile
strength Evaluation by
ODOT
Evaluation by
CSIL
Relat
Dens
Para,
(q-qc)/q
Gas
Perm
Traffic
(ADT)
Truck
Percent
YEAR
BUILT
F/T
cycles
(over 7
Yrs)
Deicer
Usage
(gln/ln-
mi-FY)
09268S 848±202 5-FAIR 86% - 87% 0.32 61.6 56700 10 1972 88 105.37
00576 648±9 4-POOR 52% - 57% 0.32 61.6 6450 8 1927 226 129.6
08958F 739±146 6-SATISFACTORY 86% - 87% 0.46 28.4 7790 11 1973 102 366.9
08682 606±47 4-POOR 47% - 48% 0.47 27.3 14200 15 1962 389 2662.56
18940 422±31 7-GOOD 61% - 67% 0.34 52.6 20600 10 2002 151 2091.09
16440 570±55 7-GOOD 44% - 45% 0.39 39.1 8332 33 1985 590 2057.78
19681 664±255 7-GOOD 65% - 68% 0.6 16.8 5454 42 2003 884 3006.02
18525 523±13
8 6-SATISFACTORY
84% - 85%
0.41 35.9 13500 3 2002 353 550.81
19268 876±11 7-GOOD - 0.8 9.5 3100 11 2005 511 2525.06
16358 589±106 7-GOOD 72% - 75% 0.29 73.5 12801 10 1986 88 1023.69
16534 465 6-SATISFACTORY 33% - 41% 0.26 86.5 9793 16 1985 88 3784.49
16844 809 6-SATISFACTORY 83% - 85% 0.39 39.4 29440 7 1990 224 165.87
NOTE: ODOT CASE
Acknowledgement
The authors acknowledge the financial support for this project provided by the Oregon Department of Transportation (ODOT) as well as the USDOT Research & Innovative Technology Administration (RITA) through Alaska University Transportation Center and Western Transportation Institute.