building mepdg climate files - purdue engineeringncaupg/activities/2012/presentation... · building...

Building MEPDG Climate Files

Dr Michael Heitzman PE

NCAT, Auburn University

1Climate Science Program

Iowa State University


Dr Gene Takle

Climate Science Program, Iowa State University


Dr Michael Heitzman PE

NCAT, Auburn UniversityNCAT, Auburn University

Dr Gene Takle


In this presentation….

� Why is climate input important

� Building historic climate files

� Building future climate files



Building future climate files

� Impact on predicted pavement performance

In this presentation….

Why is climate input important

Building historic climate files

Building future climate filesBuilding future climate files

Impact on predicted pavement performance

Pavement Design Variables

PCC ModulusCTB Modulus

Each load application



Time, years2 40

Pavement Design Variables

Traffic

PCC Modulus

HMA Modulus

Time, years

Granular Base Modulus

Subgrade Modulus

86

Modulus

Permenant Deformation: Total Rutting in Pavement La yers (inch)

0.40

0.50

0.60

0.70M

axim

um R

uttin

g (in

ch)

Ac Rutting Design Value = 0.25"

90% Reliability90% Reliability

Design LimitDesign Limit



0.00

0.10

0.20

0.30

0 18 36 54 72 90 108 126

Pavement age, month

Max

imum

Rut

ting

(inch

)

SubgradeSubgrade

Permenant Deformation: Total Rutting in Pavement La yers (inch)

SubTotalAC

SubTotalGB

SubTotalSG

Total Rutting

Predicted Predicted

RuttingRutting90% Reliability90% Reliability

TotalTotal

144 162 180 198

Total Rutting

TotalRutReliability

HMAHMA

SubgradeSubgradeAggr. BaseAggr. Base

Only 12 MEPDG climate files in Mississippi

� 4 sites with 5-6 years of climate data (very limited)

� 8 with 8-10 years of climate data (limited)

� Starting with mid 1990s

Only 12 MEPDG climate files in Mississippi

6 years of climate data (very limited)

10 years of climate data (limited)

Ames Temperature Trends



Ames Temperature Trends

Iowa Averages and Extremes

Decade Avg High Avg Low

1970s 58.9



1970s 58.9

1980s 59.6

1990s 58.4

What 10-year period do you want to use for pavement performance prediction?

Iowa Averages and Extremes

Avg Low 100°+ events

(days / weather station)

37.4 637.4 6

38.1 21

38.3 2

year period do you want to use for pavement performance prediction?

Development of

Climate Data Input Files

for the MEPDG



� Build complete 40-year historic climate files from

county measurements

� Build 40-year future climate files from global and

regional models

Development of

Climate Data Input Files

for the MEPDG

year historic climate files from

year future climate files from global and



ASOS/AWOSASOS/AWOS COOP

Analysis Grid

Grid Node



NeighborInterpolation

Analysis Grid

Grid Node

10


Iowa State University11

Complete Historic Files

� 40-year files (1970-2010)

� Each county in the State (82)




Each county in the State (82)

Mississippi County Weather Locations

32.5

33

33.5

34

34.5

35

35.5

latit

ude

12

30

30.5

31

31.5

32

32.5

-92 -91.5 -91 -90.5 -90 -89.5 -89 -88.5 -88

longitude

latit

ude

How should future climate files be built?



How should future climate files be built?

13

GLOBAL MODEL35,000 sq-mi pattern

Includes: solar radiation & green

house gasses changes

Frequency: 6 hours over 10 years

REGIONAL MODEL1200 sq-mi pattern

Includes: regional geographic

Contemporary

Scenario(decade of 1990s)



Monthly Climate “DELTAs” (for 50

Temperature DELTA = Future Scenario

Precipitation DELTA = Future Scenario / Contemporary Scenario


features and climate patterns

Frequency: 3 minutes

Future

Scenario(decade of 2040s)

GLOBAL MODELmi pattern

Includes: solar radiation & green

house gasses changes

Frequency: 6 hours over 10 years

REGIONAL MODELmi pattern


14

Monthly Climate “DELTAs” (for 50-year period)

Temperature DELTA = Future Scenario – Contemporary Scenario

Precipitation DELTA = Future Scenario / Contemporary Scenario


features and climate patterns

Frequency: 3 minutes


Iowa State University15

Average Monthly Temperature



Average Monthly Temperature

16

Temperature Distribution



Temperature Distribution

17

Average Monthly Precipitation



Average Monthly Precipitation

18

JAN FEB MAR APR MAY JUN

T [C] 1.3 1.5 3.2 2.4 2.7 1.9

P [%] -21 -13 40 14 39 13

50-year DELTA’s

1970-2010Historic Climate

JUN JUL AUG SEP OCT NOV DEC

1.9 2.8 2.0 1.7 1.9 2.0 1.4

13 -17 17 68 -20 37 -11

year DELTA’s

DELTA

( per

2010-2050Virtual Climate

( per

month)

What is the impact of more accurate climate files?

9.3-in JPCP

20 ft joint spacing

tied PCC shoulder

5.7-in lime stab base

A-2-4 subgrade

12.5-in HMA

AC-30

A-6 subgrade



A-2-4 subgrade

What is the impact of more accurate climate files?

4.5-in HMA, AC-30

3.0-in AC perm base

12-in A-2-4 base

in HMA

6 subgrade

20

8-in lime stab subgrade

A-6 subgrade


� 40-year files (1970-2010)

� Each county in the State (82)

Critical for calibration



1985-2000 pavement

� 5-yr MEPDG climate

1995-2000 climate (3x)

� HISTORIC climate

1985-2000 climate


Each county in the State (82)

Mississippi County Weather Locations

32.5

33

33.5

34

34.5

35

35.5

latit

ude

21

30

30.5

31

31.5

32

32.5

-92 -91.5 -91 -90.5 -90 -89.5 -89 -88.5 -88

longitude

latit

ude

� 40-year climate files

� each climate region (10)

Critical for predicting performance

Complete Future Files




2010-2030 design

� 5-yr MEPDG climate

1995-2000 climate (4x)

� FUTURE climate

2010-2030 virtual climate


Complete Future Files

22


PVMT TYPE

PAVEMENT PERFORMANCE

CLIMATE COMPARISON

PCC FAULT MEDPG-Historic MEPDG-Virtual Historic-Virtual PCC RIDE MEDPG-Historic MEPDG-Virtual Historic-Virtual HMA1 RUTTING MEDPG-Historic MEPDG-Virtual Historic-Virtual



Historic-Virtual HMA1 RIDE MEDPG-Historic MEPDG-Virtual Historic-Virtual HMA2 RUTTING MEDPG-Historic MEPDG-Virtual Historic-Virtual HMA2 RIDE MEDPG-Historic MEPDG-Virtual Historic-Virtual

Mississippi Climate Zone

1 2 3 4 5 6 7 8 9 10

S S S S S S S S S

23

S S S S S S S S S S S S S S S S S S S S S S S S

Faulting (M-H)

0.0250.03

0.0350.04

0.0450.05

Fa

ult

ing

(in

)

9.3-in JPCP



-0.01-0.005

00.005

0.010.015

0.020.025

1 2 3 4 5 6 7 8 9 10

Zones

Fa

ult

ing

(in

)

Faulting (H-V)

0.0250.03

0.0350.04

0.0450.05

Fa

ult

ing

(in

)

in JPCP

24

-0.01-0.0051E-170.005

0.010.015

0.020.025

0.03

1 2 3 4 5 6 7 8 9 10

Zones

Fa

ult

ing

(in

)

Rutting (M-H)

0.15

0.2

0.25

Ru

ttin

g (

in)

12.5-in HMA



-0.05

0

0.05

0.1

1 2 3 4 5 6 7 8 9 10

Zones

Ru

ttin

g (

in)

Rutting (H-V)

0.15

0.2

0.25

Ru

ttin

g (

in)

in HMA

25

M-V Zone(1-10),

-0.05

0

0.05

0.1

1 2 3 4 5 6 7 8 9 10

Zones

Ru

ttin

g (

in)

Rutting (M-H)

0.15

0.2

0.25

Ru

ttin

g (

in)

4.5-in HMA



-0.05

0

0.05

0.1

0.15

1 2 3 4 5 6 7 8 9 10

Zones

Ru

ttin

g (

in)

Rutting (H-V)

0.15

0.2

0.25

Ru

ttin

g (

in)

in HMA

26

M-V Zone(1-10),

-0.05

0

0.05

0.1

0.15

1 2 3 4 5 6 7 8 9 10

Zones

Ru

ttin

g (

in)

Zone 4 Rutting Thin HMA

0.8

1

1.2

rutti

ng (i

nche

s)

MEPDG



0

0.2

0.4

0.6

1 61 121 181

time (months)

rutti

ng (i

nche

s)

Zone 4 Rutting Thin HMA

HIST VIRT

27

241 301 361 421

time (months)

Historic v MEPDG (Wash Co - thin HMA)

70

80

90

100

110

Mon

thly

Max

Tem

p

MAX-historical MAX-MEPDG



30

40

50

60

70

0 10 20 30 40

month (MEPDG 8/99 - 6/05)(Historical 8/70 - 12/76)

Mon

thly

Max

Tem

p

Historic v MEPDG (Wash Co - thin HMA)MAX-MEPDG AVG-Historical AVG-MEPDG

28

40 50 60 70 80 90

month (MEPDG 8/99 - 6/05)(Historical 8/70 - 12/76)

Current MEPDG 10- year climate files may adversely impact pavement performance predictions� The fix is accurate and improves MEPDG model calibr ation

Future climate may be different from historic clima te and change pavement performance predictions� There are accepted scientific models to build futur e climate

files



year climate files may adversely impact pavement performance predictions

The fix is accurate and improves MEPDG model calibr ation

Future climate may be different from historic clima te and change pavement performance predictions

There are accepted scientific models to build futur e climate

29


Dr. Michael Heitzman, PE


[email protected]



Dr. Gene Takle


[email protected]


Dr. Michael Heitzman, PE


[email protected]

30

Dr. Gene Takle


[email protected]

building mepdg climate files - purdue engineeringncaupg/activities/2012/presentation... · building...

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