This document presents a study on using a disaster propagation model to analyze the impact of rainfall on a regional freeway network in Southeast China. The study develops a model to estimate travel times on the network under varying rainfall conditions. It evaluates the model using real traffic and precipitation data. The results show the model can accurately estimate travel times for passenger cars and trucks, with most estimates falling within the confidence interval of observed travel times. The study concludes the model provides an effective way to evaluate the direct and indirect losses rainfall can cause to transportation systems and critical infrastructure.

1. Using Disaster Propagation Model to
Study Rainfall Impact on Regional
Freeway Network
Jiayuan YE, Saini YANG, Xuechi ZHANG, Shuai HE
Beijing Normal University

2. Introduction
 Transportation
 Critical Infrastructure
 Essential for the functioning of society and economy
 Heavily impacted by disastrous event causing direct and
indirect losses
 Rainfall Impact on Highway Traffic Network
 Typical hazard in Southeast China
 Modeling rainfall impact on travel time
 System interdependency
 Accumulated effects of rainfall impact
 Travel delay analysis and estimation
4th International Disaster and Risk Conference IDRC Davos 2012
"Integrative Risk Management in a Changing World - Pathways to a Resilient Society"
26-30 August 2012
Davos, Switzerland

3. Concept Model

4th International Disaster and Risk Conference IDRC Davos 2012
"Integrative Risk Management in a Changing World - Pathways to a Resilient Society"
26-30 August 2012
Davos, Switzerland

4. Rainfall Impact
mm
8
Hourly Precipitation 10%
Hourly Rainfall Impact
Rainfall impact
6
8%
4 6%
2 4%
2%
0 Precipitation
1 2 3 0%
Time series
1 Time 2
series 3
Assumption
(Uniform distributed)
1.8%
mm Sub-hourly Rainfall Impact
0.7 Sub-hourly Precipitation 1.6%
0.6 1.4%
0.5 1.2%
0.4 1.0%
0.8%
0.3
0.6%
0.2
0.4%
0.1 0.2%
0 0.0%
1.1 1.5 1.9 2.3 2.7 3.1 3.5 3.9 1.1 1.5 1.9 2.3 2.7 3.1 3.5 3.9
Time Series
Time Series
4th International Disaster and Risk Conference IDRC Davos 2012
"Integrative Risk Management in a Changing World - Pathways to a Resilient Society"
26-30 August 2012
Davos, Switzerland

5. Recovery Process & Impact Propagation

1 2 3 4 5 6 7
Traffic flow direction
4th International Disaster and Risk Conference IDRC Davos 2012
"Integrative Risk Management in a Changing World - Pathways to a Resilient Society"
26-30 August 2012
Davos, Switzerland

6. Case Study on Traffic Network
Model Assessment

7. Data & Process - Precipitation
 Precipitation Data
 Hourly precipitation intensity
 6-hourly precipitation intensity
 Spatial interpolation of Precipitation
 Inverse Distance Weight Method (IDWM)
 Ordinary Kriging Method (OKM)
Meteorological IDWM OKM
Station No. MAE MSE MAE MSE
59287 5.77 107.48 6.09 102.77
59478 5.00 56.61 4.98 56.15
59271 5.57 113.66 6.70 144.37
59462 4.23 40.27 5.07 52.47
Mean 5.14 79.50 5.71 88.94
4th International Disaster and Risk Conference IDRC Davos 2012
"Integrative Risk Management in a Changing World - Pathways to a Resilient Society"
26-30 August 2012
Davos, Switzerland

8. Data & Process – Travel time

4th International Disaster and Risk Conference IDRC Davos 2012
"Integrative Risk Management in a Changing World - Pathways to a Resilient Society"
26-30 August 2012
Davos, Switzerland

9. Model Result Analysis
12:02:18 AM
 Passenger Cars
12:02:01 AM
12:01:44 AM
12:01:26 AM
Travel Time
12:01:09 AM
Error
12:00:52 AM
Upper Bound of 95% confidence Interval
Lower Bound of 95% confidence Interval
12:00:35 AM Mean Travel Time
Model Result
12:00:17 AM
12:00:00 AM
1 25 49 73 97 121 145 169 193 217 241 265 289 313 337
Hourly Time Series
 68.46% estimated travel time of 241 records are in the range
of 95% confidence interval
 Relative error value varies from -19.23%～24.15%
 mean value of overestimated relative error is 5.71%
 mean value of underestimated relative error is 6.73%
4th International Disaster and Risk Conference IDRC Davos 2012
"Integrative Risk Management in a Changing World - Pathways to a Resilient Society"
26-30 August 2012
Davos, Switzerland

10. Model Result Analysis
12:02:36 AM
 Trucks
12:02:18 AM
12:02:01 AM
12:01:44 AM
Travel Time
12:01:26 AM
Error
12:01:09 AM
Upper Bound of 95% confidence Interval
12:00:52 AM Lower Bound of 95% confidence Interval
Mean Travel Time
12:00:35 AM
Model Result
12:00:17 AM
12:00:00 AM
1 25 49 73 97 121 145 169 193 217 241 265 289 313 337
Hourly Time Series
 59.61% estimated travel time of 307 records are in the range
of 95% confidence interval
 Relative error value varies from -18.70%～26.51%
 mean value of overestimated relative error is 5.98%
 mean value of underestimated relative error is 6.00%
4th International Disaster and Risk Conference IDRC Davos 2012
"Integrative Risk Management in a Changing World - Pathways to a Resilient Society"
26-30 August 2012
Davos, Switzerland

11. Discussion & Conclusion
 Discussion
 Regional Travel Time Estimation
 Time Penalty Risk Analysis
 Probability Distribution of Precipitation
 Accurate disaster character data in high temporal-resolution
 Conclusion
 Regional highway network travel time estimation in the
condition of adverse weather
 Fast evaluation of disaster impact immediately after disaster
 Indirect loss assessment of transportation by disastrous events
 Extended study of disastrous events impact on integrated CI
systems
4th International Disaster and Risk Conference IDRC Davos 2012
"Integrative Risk Management in a Changing World - Pathways to a Resilient Society"
26-30 August 2012
Davos, Switzerland