Impact of Earthquakes on the Transportation Infrastructure of Indonesia: a Preliminary Study
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Civil Engineering Dimension, Vol. 21, No. 1, March 2019, 19-28 DOI: 10.9744/CED.21.1.19-28 ISSN 1410-9530 print / ISSN 1979-570X online Impact of Earthquakes on the Transportation Infrastructure of Indonesia: A Preliminary Study Amirsardari, A.1, Sofi, M.1*, Lumantarna, E.1, Imran, I.2, and Duffield, C.1 Abstract: Indonesia is a high seismic region and one of the most vulnerable countries prone to experiencing damaging earthquakes. It is critical that lifeline infrastructure remain operational or is quickly remediated after an earthquake to minimise physical, social, and economical losses. Not much work has been carried out in understanding the effect of earthquakes on transpor- tation infrastructure systems. This study aims to gain a better understanding of the impact of earthquakes on the transportation infrastructure in Indonesia. This is achieved by firstly review- ing the frameworks and tools for conducting seismic risk assessment of lifeline infrastructure. The critical components of the transportation system are then identified. Various forms of tran- sportation infrastructure damage caused by earthquakes are discussed. An overview of the damaging earthquakes for the past 20 years is presented. Finally, conclusions and recommen- dations are provided about the future work required for conducting risk assessment of the transportation infrastructure in Indonesia Keywords: Earthquake vulnerability; transportation system; infrastructure; Indonesia; seismic risk. Introduction Most of the research that has been conducted thus far has focused on assessing the seismic performance Indonesia is one of the world’s most vulnerable coun- of structures and point systems [3,4]. Less work has tries prone to natural disasters, including earthqua- been conducted in understanding the effect of earth- kes, tsunamis, volcanic eruptions, and seasonal ty- phoons [1]. Natural disasters can have catastrophic quakes on lifelines including transportation systems. impact on both a regional and national level as they One of the main reasons for this is due to the higher cause physical, social, and indirect economic losses. level of complexity involved in accurately conducting Physical losses comprise of direct losses due to the seismic assessment of lifelines which often in- damage to the environment, including structures clude both structural and geotechnical failure me- and infrastructures. Social losses include fatalities, chanisms and the interdependency of the various injuries, emotional harm, and social unrest. Indirect components of the system. economical losses account for losses induced post- earthquake due to changes caused to daily activities The aim of this study is to gain a better understand- of a region such as loss or reduced functionality of various systems and services. ing of the impact of earthquakes on the transporta- tion system in Indonesia. A brief review is provided Often, risk assessment is conducted to reduce losses of the frameworks for conducting seismic risk assess- and to mitigate the effect of natural disasters. Risk ment which are particularly suitable for lifelines. mitigation strategies are particularly important for The various components of the transportation sys- lifelines; which are defined as systems which are necessary for human life and urban function [2]. An tem with relation to Indonesia are identified and the important lifeline infrastructure is the transporta- various forms of physical damage caused by earth- tion system. Its performance is critical during and quakes to the transportation infrastructure are dis- immediately after a disastrous event as they are cussed. Furthermore, an overview of the damaging required for emergency response and disaster relief earthquakes for the past 20 years is presented to efforts. In the long-term their performance is also provide an indication of the recent losses which have important in order to minimise indirect losses since occurred in Indonesia due to the damage caused to transportation systems provide the means for many transportation systems. Based on the findings, re- important daily functions. commendations and conclusions are provided about 1 Department of Infrastructure Engineering, University of Mel- the future work required for conducting risk assess- bourne, Parkville, 3010, AUSTRALIA ment of the transportation system in Indonesia. 2 Bandung Institute of Technology, Bandung, Jl. Ganesha No.10, Lb. Siliwangi, Coblong, Bandung 40132, INDONESIA *Corresponding author; email: [email protected] Framework for Seismic Risk Assessment Note: Discussion is expected before June, 1st 2019, and will be published in the “Civil Engineering Dimension”, volume 21, One of the first initiations for assessing the seismic number 2, September 2019. vulnerability and impact of disruption of lifeline sys- Received 17 December 2018 revised 20 January 2019; accepted 19 tems was in 1988 by the Applied Technology Council March 2019 19 Amirsardari, A. et al. / Impact of Earthquakes on the Transportation Infrastructure of Indonesia / CED, Vol. 21, No. 1, March 2019, pp. 19–28 (ATC) with the support from the Federal Emergency required. This usually necessitates the implementa- Management Agency (FEMA). The research which tion of a geographical information system (GIS). This was conducted is presented in ATC 25/FEMA 224 has led to the development of numerous software report; “Seismic vulnerability and impact of disrupt- packages and tools, such as Redars [7] and Hazus tion of lifelines in the conterminous United States,” [8]. Redars is seismic-risk-analysis software package [2]. The proposed framework, illustrated in Figure 1, developed by the California Department of Tran- consists of four steps: (i) development of a national sportation under the FHWA-MCEER Motorway lifeline inventory database, (ii) development of seis- Project (initiated in 1992) which is capable of estima- mic vulnerability functions for each lifeline compo- ting the structural and operational losses of tran- nent/system (these functions describe the expected sportation systems [5,6]. HAZUS methodology and seismic performance of each lifeline as well as the software package has also been developed in the US, time required to restore damaged infrastructure and it is capable of predicting the direct physical damage facilities to their pre-earthquake capacity or usabi- and functionality of various transportation compo- lity, (iii) characterisation and quantification of the nents, however, unlike REDARS, it is not able to seismic hazard nationwide, and (iv) development of account for the interdependence of various transpor- direct damage loss estimates (i.e., damage resulting tation systems and it is incapable of conducting net- directly due to ground shaking and other induced work analysis [5]. Ina SAFE is a similar tool which mechanisms) and indirect economic loss estimates has been developed for Indonesia by the Indonesian (i.e., losses due to disruptions to lifeline functionality) Government (BNPB), Australian Government, and for a particular earthquake scenario. the World Bank (GFDRR) [9]. While the platform is freely available the data required to assess the risk The framework presented in Figure 1 has formed the of transportation systems is incomplete and it does foundation of many other studies which have con- not incorporate the interdependence of various tran- ducted assessment of lifelines. However, most of the sportation components. research that has been conducted has focused on quantifying the direct losses due to earthquakes for Components of the Transportation Infrastruc- isolated structures/infrastructure. It is only over the ture recent years that there has been a move to quanti- fying indirect losses and adopting network analysis A critical part of accurately conducting risk assess- methods to account for the interdependencies of net- ment of the transportation system involves develop- work components [e.g., 5,6]. Indirect losses are ing an inventory of the key components of the tran- dependent on residual-capacity or time-to-restora- sportation infrastructure. The transportation system tion curves which define the percentage of function can be categorised into four groups: roadway, rail- restored as a function of time. For point systems road, waterway, and air transportation system. The (e.g., airports, schools, and hospitals), the time-to- components of the various groups are described restoration curves are developed for isolated struc- below in relation to Indonesia. It is noted that most tures. However, for linear systems (e.g., roadways of the information which is presented is obtained and railroads), the time-to-restoration curves require from the country report conducted by the Association connectivity analyses and serviceability analyses [2]. of Southeast Asian Nations (ASEAN) Coordinating Centre for Humanitarian Assistance on Disaster To accurately conduct the risk analysis of lifeline Management (AHA Centre) and the Japan Inter- infrastructures extensive spatial distribution data is national Cooperation Agency [10]. Figure 1. Framework for Conducting Seismic Risk Assessment of Lifelines, adapted from [2] 20 Amirsardari, A. et al. / Impact of Earthquakes on the Transportation Infrastructure of Indonesia / CED, Vol. 21, No. 1, March 2019, pp. 19–28 Roadway Transportation System bridges in Indonesia with a combined length of 1138 km. Approximately 77% (734 km) of the brid- The main components of the roadway transportation ges are part of provincial, regency, and city roads, system