welcome to eprints soton - eprints soton€¦ · web viewwong th, mansor sb, mispan mr, ahmad n,...

15
SECED 2015 Conference: Earthquake Risk and Engineering towards a Resilient World 9-10 July 2015, Cambridge UK AN ASSESSMENT OF EARTHQUAKE VULNERABILITIES IN KATHMANDU, NEPAL FOR IDENTIFICATION OF OPTIMAL IMMEDIATE AID SITES Andrew MACLACHLAN 1 , Eloise BIGGS 2 and John BEVINGTON 3 Abstract: Pre-event vulnerability assessments are an emerging discipline within earthquake risk studies. However, owing to extensive data collection for appropriate building stock representation and associated vulnerability, the majority of studies fail to comprehend the multifaceted nature of building vulnerability for pre-event assessments. Furthermore, few studies explore optimal immediate aid sites for the distribution of aid materials in a post- event scenario. New and novel tools recently released by the Global Earthquake Model (GEM) are implemented to overcome limitations of previous studies, permitting standardised repeatable Worldwide results, fulfilling the call from the Organisation for Economic Cooperation and Development (OCED) for the establishment of open source risk assessment tools. Introduction In the last decade more than 200,000 people lost their lives due to ramifications associated with earthquakes, with a global annual average loss of $18.65 billion in economic damage observed between 2000 and 2009 (Jaiswal et al., 2011; Guha-Sapir et al., 2011). In Nepal, over 11,000 people died from earthquake consequences during the 20th Century. Evidently earthquakes present a significant hazard to society not only in terms of human fatalities but also economic cost. Consequently, pre-earthquake vulnerability assessments that are capable of informing policy for future city development are critical for reducing risk (Geiß and Taubenböck, 2013). Kathmandu Valley exhibits a multifaceted issue regarding earthquake vulnerability. The Indian plate is subducting under the Eurasian plate, with no significant earthquake having occurred in the Himalaya during the last three centuries, presenting a significant earthquake risk (Bilham et al. 2001; Gupta and Gahalaut, 2014). The Valley has a vast population of 2.5 million with a high annual growth rate of 5-7% (Roberts, 2013). Additional characteristics include: poor urban planning, with low compliance of building codes; 1 Mr, University of Southampton, Southampton, [email protected] 2 Dr, University of Southampton, Southampton, [email protected] 3 Dr, ImageCat Ltd., London, [email protected]

Upload: others

Post on 18-Jul-2020

4 views

Category:

Documents


0 download

TRANSCRIPT

Page 1: Welcome to ePrints Soton - ePrints Soton€¦ · Web viewWong TH, Mansor SB, Mispan MR, Ahmad N, Sulaiman WNA (2003) Feature extraction based on object oriented analysis , Proceedings

SECED 2015 Conference: Earthquake Risk and Engineering towards a Resilient World9-10 July 2015, Cambridge UK

AN ASSESSMENT OF EARTHQUAKE VULNERABILITIES INKATHMANDU, NEPAL FOR IDENTIFICATION OF OPTIMAL

IMMEDIATE AID SITES

Andrew MACLACHLAN1, Eloise BIGGS2 and John BEVINGTON3

Abstract: Pre-event vulnerability assessments are an emerging discipline within earthquake risk studies. However, owing to extensive data collection for appropriate building stock representation and associated vulnerability, the majority of studies fail to comprehend the multifaceted nature of building vulnerability for pre-event assessments. Furthermore, few studies explore optimal immediate aid sites for the distribution of aid materials in a post-event scenario. New and novel tools recently released by the Global Earthquake Model (GEM) are implemented to overcome limitations of previous studies, permitting standardised repeatable Worldwide results, fulfilling the call from the Organisation for Economic Cooperation and Development (OCED) for the establishment of open source risk assessment tools.

IntroductionIn the last decade more than 200,000 people lost their lives due to ramifications associated with earthquakes, with a global annual average loss of $18.65 billion in economic damage observed between 2000 and 2009 (Jaiswal et al., 2011; Guha-Sapir et al., 2011). In Nepal, over 11,000 people died from earthquake consequences during the 20th Century. Evidently earthquakes present a significant hazard to society not only in terms of human fatalities but also economic cost. Consequently, pre-earthquake vulnerability assessments that are capable of informing policy for future city development are critical for reducing risk (Geiß and Taubenböck, 2013).

Kathmandu Valley exhibits a multifaceted issue regarding earthquake vulnerability. The Indian plate is subducting under the Eurasian plate, with no significant earthquake having occurred in the Himalaya during the last three centuries, presenting a significant earthquake risk (Bilham et al. 2001; Gupta and Gahalaut, 2014). The Valley has a vast population of 2.5 million with a high annual growth rate of 5-7% (Roberts, 2013). Additional characteristics include: poor urban planning, with low compliance of building codes; and underlying sediment being mostly composed of lacustrine materials and the Valley being surrounded by four mountains, which may trap and redistribute seismic energy. Subsequently the cumulative effect of such characteristics presents a catastrophic scenario in the event of a major earthquake.

Pre-event vulnerability assessments have the power to significantly reduce casualties and mortalities if used in the appropriate manner. They require a form of exposure dataset (commonly buildings), associated vulnerability (being the predicted effects of shaking on the exposure dataset) and seismic hazard (Pittore and Wieland, 2013). A large portion of academic literature only considers physical vulnerability in terms of building exposure. In this regard structural analysis is undertaken whereby the structural capacity (capacity load) to sustain seismic loads is compared to the earthquake demand, termed ‘capacity curve’ (Nastev, 2013). The capacity curve is generally derived from the yield capacity point of the building; being the force that exceeds the buildings resistance. A building will only remain standing if the ultimate capacity point is not exceeded; the point at which the building can no longer withstand the force. Subsequently, the building moves from elastic to plastic

1 Mr, University of Southampton, Southampton, [email protected] Dr, University of Southampton, Southampton, [email protected] Dr, ImageCat Ltd., London, [email protected]

Page 2: Welcome to ePrints Soton - ePrints Soton€¦ · Web viewWong TH, Mansor SB, Mispan MR, Ahmad N, Sulaiman WNA (2003) Feature extraction based on object oriented analysis , Proceedings

A MACLACHLAN, E BIGGS2 and J BEVINGTON3

deformation (Malladi, 2012). Following this, building-specific vulnerability functions (or models) identify the relationship between seismic intensity and damage to structures (defined in the exposure model), providing the probability of fraction of loss with associated ground shaking, derived from fragility curves (models of functions) indicating the probability of occurrence per damage state in relation to the hazard and capacity curve (Chaulagain et al., 2015; Silva, et al., 2013; Thapaliya, 2006).

However, the majority of countries, in particular developing countries do not possess appropriate building stock data. Consequently, alternative methods are sought in order to generate building stock datasets. In this regard satellite remote sensing plays an integral part in building stock generation. Nevertheless, earthquake prone developing countries are often precluded from undertaking analysis due to the lack of country specific vulnerability functions and earthquake models. The Global Earthquake Model (GEM) aims to heighten public understanding for effective decision-making in earthquake scenarios. Consequently the GEM constitutes a free toolset, including: the Inventory Data Capture Tools (IDCT)4 (Hu et al., 2014), the Spatial Inventory Data Developer (SIDD) (Hu et al., 2014; Porter et al., 2014) and OpenQuake (Crowley et al., 2014) to provide a transparent, repeatable and straight forward methodology for utilising remote sensing with optimal ground data collection. The methodology permits a systematic and standardised data flow for: field data collection, mapping scheme review (a zonal statistically inferred building stock distribution), exposure dataset generation and subsequent use within a Global earthquake model loaded with associated vulnerability data. Geiß and Taubenböck (2013) and Mück et al., (2013) indicated that the GEM methodology has the potential to overcome previous limitations, fulfilling the call from the Organisation for Economic Cooperation and Development’s (OCED) Global Science Forum for development of open-source risk assessment tools, highlighting the importance of this, and subsequent research (Pinho, 2012).

The ideology underpinning pre-disaster planning is to minimise delay in providing commodities and healthcare in order to reduce potential human suffering. With the Hyogo Framework of Action (HFA) highlighting preparedness as one of the five priorities for action between 2005 to 2015 (Anhorn and Khazai, 2014; Balcik and Beamon, 2008; Yi and Özdamar, 2007). Nevertheless, due to the unpredictability of natural disasters and response of the built environment it can be inherently difficult to identify optimal locations for services. In this regard several models have been developed in order to identify potential locations, including: a dynamic logistics and coordination model for evacuation and support (Yi and Özdamar, 2007) and a pre-positioning and dynamic delivery planning model (Rawls and Turnquist, 2012). However, the majority of research implements simple metrics to infer building damage and population displacement. Additionally, little research explores identification of suitable areas for aid distribution, being one of the most important factors in the immediate aftermath of a disaster (Anhorn and Khazai, 2014).

Study SiteKathmandu is the capital and largest urban agglomerate of Nepal; the city is one of fastest growing in South Asia (Fernandez et al., 2006; Mohanty, 2011). The Valley is centred geographically in Nepal and is made up of three administrative districts: Kathmandu, Lalitpur and Bhaktapur. There are five municipalities within the Valley, namely; Kathmandu Metropolitan City (KMC), Lalitpur Sub-Metropolitain City (LSMC), Bhaktapur Municipality (BM), Madhyapur (Thimi) Municipality (MM) and Kirtipur Municipality (KM) and 98 Village Development Committees (Dixit et al., 2013). KMC is the largest municipality and obtains the majority of Government offices. Whilst the entire Valley is considered the capital of Nepal, only KMC was investigated for this project, drawing similarities from other research (Dixit et al., 2013; Anhorn and Khazai, 2014).

4 To see an example of the IDCT please refer to the instructional video created for this project at: https://www.youtube.com/watch?v=6GVjwJxmivM

2

Page 3: Welcome to ePrints Soton - ePrints Soton€¦ · Web viewWong TH, Mansor SB, Mispan MR, Ahmad N, Sulaiman WNA (2003) Feature extraction based on object oriented analysis , Proceedings

A MACLACHLAN, E BIGGS2 and J BEVINGTON3

In the last century Nepal has only experienced two devastating earthquakes. A Richter Scale Magnitude (M)8.1 earthquake occurred in January 1934 with an epicentre near the Indian border, with the Kathmandu Valley experiencing intensities of IX-X on the Modified Mercalli Intensity Scale (MMI). 8,519 people were reported dead, with 4,296 located in Kathmandu Valley. A M6.8 earthquake occurred in August 1988, with an epicentre in Eastern Nepal. Kathmandu Valley experienced an MMI of VII-VIII, with 721 deaths throughout Nepal (Dixit et al. 2013). Current Global Positioning System (GPS) measurements indicate a convergence rate of 20 ± 3mm/year (Bilham et al., 2001; Gupta and Gahalaut, 2014). Bilham et al., (2001) divided the Central Himalaya into ten regions of 220km. Given the specified rate of convergence six regions were identified to have a slip potential of at least 4m, equivalent to the 1934 earthquake. However, owing to the historic record indicating no great earthquake throughout the Himalaya since 1700 the slip potential may have increased to 6m in some areas. Furthermore, due to the earthquakes of 1905 and 1934 not revealing surface ruptures but warping river terraces and growing foothills, parts of the Himalaya may not have ruptured for 500 to 700 years, generating a potential slip exceeding 10m in some areas. Thus, aforementioned earthquakes would be considered atypically small, evidently highlighting the need for pre-event vulnerability assessments for earthquake risk mitigation in Kathmandu Valley.

MethodologyBefore a ground survey for generating a building exposure dataset (or model) can be commenced a building taxonomy must be defined. Unfortunately the majority of building taxonomies have a regional or country-based focus, or only contemplate structural components. Additional attributes surrounding general building information, non-structural elements, occupancy, construction affecting earthquake performance and retrofit work all contribute to building performance, considered by the GEM taxonomy. The GEM building taxonomy portrays a unique building description, similar to a genetic code (genome). The building genome is composed of 13 attributes, each representing a specific characteristic that affects seismic performance.

A level 2 exposure dataset was generated through data aggregation into a mapping scheme, being a statistically inferred distribution of building stock applied to homogenous zones. Homogenous zones were delineated to the GEM sample 3 classification using Pléiades pan-sharpened 50cm orthorectified multispectral imagery of KMC provided by Astrium Services, OpenStreetMaps (OSM), Google Earth and Panoramio.

Building outlines were extracted from the satellite imagery. However, within the urban environment traditional pixel-based classification analysis presents multiple challenges owing to different urban land types having a similar spectral reflectance (Erener, 2013; Myint et al., 2011). Object-Based Image Analysis (OBIA) permits image division based on pixel groups obtaining similar spectral and spatial properties, enabling superior classification in an urban context (Blaschke et al., 2000; Myint et al., 2011; Wong et al., 2003). A Multiresolution Segmentation Algorithm (MSA) employing a fractal net evolution approach utilising local mutual best-fit heuristics to identify the least heterogeneous merge in the local area, following a gradient of best fit was implemented (Blaschke et al., 2000). The non-parametric standard nearest neighbour classifier was utilised for image classification, being advantageous where spectrally similar classes are not easily separable (Myint et al., 2011)

Building characteristic surveys were collected through the IDCT on android tablet devices, implementing the GEM Building Taxonomy (Jordan et al., 2014; Brzev et al., 2013). The Nepal National Society of Earthquake Technology (NSET) agreed to recruit and train (based on provided materials) 16 students for data collection with a sample size of 478 buildings. Sampling was undertaken through allocating wards to students at the request of the NSET to

3

Page 4: Welcome to ePrints Soton - ePrints Soton€¦ · Web viewWong TH, Mansor SB, Mispan MR, Ahmad N, Sulaiman WNA (2003) Feature extraction based on object oriented analysis , Proceedings

A MACLACHLAN, E BIGGS2 and J BEVINGTON3

reduce travelling time after reviewing initial documentation that specified homogenous zone division. The sampling design tool produced by the National Oceanic and Atmospheric Administration (NOAA) facilitated proportional building homogenous zone selection based on the total number of required buildings (478). Some attributes of the GEM taxonomy required in-depth building attributes to be obtained. Therefore, a document of tables was provided for an expert from the NSET to complete in order to identify the most likely internal building characteristics (i.e. lateral load resisting system) from visible external characteristics. Pléiades multispectral imagery and OSM data covering the study area were processed to online publishable tiles for compatibility compliance with the IDCT. Additionally 16 sample files containing digital and printed sample locations for each student were provided and loaded onto individual tablets.

The SIDD permitted generation of an exposure dataset through assignment of mapping schemes, being a statistical summary of: construction type, internal building characteristics, era and height defined by the GEM building taxonomy to homogenous zones (Hu et al., 2014). It enables a simplification of complex processes that structural engineers undertake in order to develop building exposure. For each type of homogenous zone the SIDD generates a preliminary mapping scheme, with a subsequent iterative adjustment and addition of secondary modifiers for zone characterisation (Hu et al., 2014).

Aid site selection followed logic by Anhorn and Khazai (2014), assuming a ‘worst case’ scenario in which aid location is exclusively based on open space. In order to identify initial optimal aid locations, factors influencing aid locations were extracted from OSM, namely: major roads, hospitals and schools. These factors were selected due to possible migration toward public buildings in the event of an earthquake. Schools are commonly used for initial protection, whilst hospitals treat the injured with people normally gravitating towards roads in an attempt to reach services (Anhorn and Khazai, 2014). It is appreciated that the majority of roads may be impassable, however major roads often have a clear buffer between buildings and the road surface, potentially reducing the impact of rubble, permitting some sort of accessibility. Following this a cost surface was produced based on defined homogenous zones. It was assumed that one person could walk 3.6km per hour. Homogenous zones were reclassified based on urban density due to possible collapse of urban features that could preclude direct passage. Similarly, road types were also reclassified based on logic that major roads would incur less direct damage. Consequently a cost surface was produced and input into cost distance for: hospitals, schools and major roads. An average of the outputs was taken generating an initial optimal aid map indicating average time to the three factors. Examination of the satellite imagery for potential aid locations was undertaken through manual interpretation. Extraction though image-processing software was contemplated, however due to the heterogeneous characteristics of initial sites manual identification was preferenced. Potential sites were selected based on the amount of open space and distance from buildings. The mean value of the initial optimal aid map was extracted through zonal statistics as table.

Buildings were assigned a ward based on the shape file provided by NSET. The number of buildings per ward was then extracted, with the population per ward obtained from the Nepal Bureau of Statistics (NCBS) being divided by the number of buildings to produce average number of people per building per ward. Furthermore, aid site capacity (number of people) was identified following logic that one person requires 9m2 of space as stated in Anhorn and Khazai (2014). A network dataset was then generated based on OSM roads. A subsequent maximum capacity location-allocation problem was initiated, with buildings defined as demand points and aid sites as facilities. This was considered more appropriate for immediate emergency aid sites, covering as many possible demand points rather than minimising distance between supply and demand (Anhorn and Khazai, 2014; Indriasari et al., 2010). Cost distance of unallocated buildings permitted identification of aid sites in

4

Page 5: Welcome to ePrints Soton - ePrints Soton€¦ · Web viewWong TH, Mansor SB, Mispan MR, Ahmad N, Sulaiman WNA (2003) Feature extraction based on object oriented analysis , Proceedings

A MACLACHLAN, E BIGGS2 and J BEVINGTON3

preferential locations for immediate aid distribution in order to service the greatest number of unallocated people seeking aid.

Implementation of the mapping scheme and exposure datasets permitted a more realistic depiction of unallocated buildings and aid seeking population. Homogenous zones were ranked based on building attributes. In the four most vulnerable homogenous zones it was assumed all residents would seek aid, in the next seven half would seek aid, and in the final three only a quarter would seek aid. The maximum capacity location-allocation problem was re-run considering building vulnerability.

Results/DiscussionDelineation of homogenous zones highlighted the vast urban agglomerate that KMC presents; with 75.67% of KMC being identified as residential (Bhattarai and Conway, 2010). Moreover, when this was decomposed to the most detailed sample level; Moderate Residential density 2 (Mr) and High Residential density 2 (Hr) combine to represent 41.74% of the area within KMC. Additionally, whilst core wards appear to have a relatively low population and relatively small number of buildings; when the average number of people per building is computed core wards exhibit an average between 22.40 and 29.31 people per building, highlighting the sheer volume of residential areas, buildings and associated population within KMC, making the 2021 target ratio of 40:60 of built to non-built seem somewhat unrealistic (Bhattarai and Conway, 2010).

Including a form of building exposure and subsequently altering population to be representative of those seeking aid is exhibited in Figure 1 and Table 1 reducing unallocated population from 75.8% to 70%. Whilst this result is still concerningly high, preferencial aid sides identified in Figure 1 and Table 1 have the potential to substantially reduce mortality.

5

Page 6: Welcome to ePrints Soton - ePrints Soton€¦ · Web viewWong TH, Mansor SB, Mispan MR, Ahmad N, Sulaiman WNA (2003) Feature extraction based on object oriented analysis , Proceedings

A MACLACHLAN, E BIGGS2 and J BEVINGTON3

89

7

6

10

27 6660

54

46

3670

72

74

67

41 22

30

49

64

28

23

58

45

38

47

35

50

55

52

3433

40

37

32

6871

25

5626 69

73

31

61

42

53

24

51

29

62

21

65

44

63

48

5759

13

12

17

11

1614

19

18

20

45

1

2

3

Coordinate System: WGS 1984 UTM Zone 45NProjection: Transverse MercatorDatum: WGS 1984False Easting: 500,000.0000False Northing: 0.0000Central Meridian: 87.0000Scale Factor: 0.9996Latitude Of Origin: 0.0000Units: Meter

0 3 61.5 Kilometers

Ü

Source: Esri, DigitalGlobe,GeoEye, EarthstarGeographics, CNES/AirbusDS, USDA, USGS, AEX,

LegendAid site suitability (minutes to factors)

3.09 - 4.87

4.88 - 6.89

6.90 - 8.81

8.82 - 10.35

10.36 - 12.18

12.19 - 13.98

13.99 - 16.67

16.68 - 20.07

20.08 - 24.14

24.15 - 32.36

Population per building1.93 - 2.93

2.94 - 4.42

4.43 - 5.32

5.33 - 5.90

5.91 - 6.92

6.93 - 7.86

7.87 - 9.98

9.99 - 14.33

14.34 - 22.39

22.40 - 29.31

Figure 1. Combination of unallocated buildings considering homogenous zone vulnerability and initial optimal aid factors overlain on average population per building per ward. Numerically identifying the five most important aid location ranks in black, the next five in umber, the next ten in red and the rest

in cantaloupe. © OpenStreetMap contributors

6

Page 7: Welcome to ePrints Soton - ePrints Soton€¦ · Web viewWong TH, Mansor SB, Mispan MR, Ahmad N, Sulaiman WNA (2003) Feature extraction based on object oriented analysis , Proceedings

A MACLACHLAN, E BIGGS2 and J BEVINGTON3

Table 1. Statistical summary of Figure 1 for the top 20 aid sites, whilst also indicating site-ranking movement compared to analysis not considering building vulnerability: (1, ) = moved 1 rank down,

(1, )= moved 1 rank up

ObjectID (movement)

Suitability (average time to all factors

(mins))

Rank Average time to

hospital (mins)

Average time to school (mins)

Average time to

major roads (mins)

Average time to unallocated

buildings (mins)

37 3.09 1 3.76 6.16 1.00 1.44

41 3.41 2 2.65 6.13 1.40 3.43

54 3.72 3 4.84 5.52 2.33 2.12

38 4.33 4 3.74 9.39 1.19 2.99

42 4.87 5 12.25 3.03 2.38 1.76

55 (2, ) 5.56 6 6.03 10.43 5.22 0.60

32 (1, ) 5.59 7 7.46 9.47 0.98 4.39

39 (1, ) 5.89 8 6.45 11.29 1.00 4.83

40 5.99 9 7.84 12.71 1.05 2.34

26 (1, ) 6.58 10 9.45 10.76 4.51 1.56

57 (1, ) 6.86 11 6.67 16.51 2.53 1.79

65 (1, ) 6.89 12 15.12 7.66 2.02 2.71

49 (4, ) 7.24 13 10.63 10.39 6.11 1.89

33 (4, ) 7.56 14 10.58 12.19 1.27 6.24

36 (1, ) 7.74 15 11.92 8.32 7.33 3.35

56 (1, ) 8.07 16 17.87 4.63 9.14 0.59

48 (1, ) 8.10 17 20.28 5.56 4.18 2.34

60 8.48 18 21.97 10.78 0.71 0.47

52 (2, ) 8.70 19 12.61 9.54 10.84 1.83

30 8.81 20 26.86 4.06 3.65 0.70

Whilst Figure 1 identifies the most in-need aid sites in terms of unallocated population but also equally considering aid site location, contemplation must be given to the ethics of humanitarian aid. The primary aim of humanitarian assistance is to meet human needs and address human suffering where found (Nilsson et al., 2011). However, aid distribution is based upon certain factors that can result in unequal aid division and failure to distribute to the most vulnerable citizens (Nilsson et al., 2011; Rahill et al., 2014). In this research only building vulnerability was considered per homogenous zone, altering the population requiring assistance. Nevertheless, social vulnerability is aimed at identifying disadvantaged population, being constrained by economic and political capital (Geiß and Taubenböck, 2013; Walker et al., 2014). Walker et al., (2014) presented a social vulnerability index for Victoria, Canada through weighting the following factors: average income, seniors living alone, dependent population, single-parent families, housing ownership, unemployment rate, education, recent movers and language barriers (Walker et al., 2014). However, due to the NCBS only collecting raw population, social vulnerability was unable to be computed. Regardless, factors implemented by Walker et al., (2014) would not directly relate to KMC

7

Page 8: Welcome to ePrints Soton - ePrints Soton€¦ · Web viewWong TH, Mansor SB, Mispan MR, Ahmad N, Sulaiman WNA (2003) Feature extraction based on object oriented analysis , Proceedings

A MACLACHLAN, E BIGGS2 and J BEVINGTON3

owing to the complex set of culturally specific social factors determined by individual perception and importance of each factor in reaching a decision to seek aid (Bhattarai and Conway, 2010; Khazai et al., 2012). Furthermore, social vulnerability should contemplate a form of social capital. Rahill et al., (2014) explored the contested role of social capital after the 2010 Haiti earthquake. During the immediate aftermath, international aid only met a small proportion of the aid requirement. Social capital became an integral part of aid distribution; on the one hand it permitted access to those in need, whilst on the other hand it exacerbated social inequality. Consequently, citizens with the least resources were neglected, clearly highlighting the importance of including social capital within social vulnerability in determination of aid sites and earthquake risk studies, not considered by the majority of authors (Ehrlich et al., 2013; Kircher et al., 2006; Mück et al., 2013; Nastev, 2013; Pittore and Wieland, 2013; Ploeger et al., 2010; Wieland et al., 2012).

To mitigate potential devastation after a major earthquake a paradigm shift in the very concept of humanitarian aid is required. In this theme humanitarian aid needs to consider pre-event assistance in the form of physical vulnerability, social vulnerability and sociological factors surrounding earthquakes. In order for this to occur, humanitarian aid donors themselves need to overcome the sociological factors of aid giving. Consequently for progress to be made the Global society must change from a response-based driven approach to a prevention-based strategy (Zhang et al., 2012). Regardless, it is appreciated that difficulties can be encountered when distributing pre-event aid owing to potential corruption and misuse (Bhattarai and Conway, 2010). Therefore it is of vital importance that appropriate frameworks and rigorous checking measures are in place in order for successful pre-event aid distribution (Tucker, 2013; Zhang et al., 2012).

Study AdvancementsThe presented project utilised the generated exposure dataset in a rather simplistic manner; however, the sheer amount of attributes collected within the exposure dataset facilitates broad project expansion with earthquake models. Nevertheless current earthquake models often only have country specific applications and estimate economic and human loss based on past-earthquake events applied to the modern day population. The soon to be released OpenQuake earthquake model attempts to remediate current issues precluding effective analysis through the creation of a global earthquake model that is homogenous as possible, considering epistemic uncertainties (Pinho, 2012).

OpenQuake is currently split into two modules: hazard and risk. The hazard module permits users to identify a potential earthquake considering factors such as: earthquake magnitude, rupture models, soil conditions, ground acceleration, peak ground acceleration and spectral acceleration (Crowley et al., 2014). Following this the risk model entails five calculation workflows: two calculate losses and damage distributions form a single earthquake, two calculate seismic risk using probabilistic seismic hazard and a final one contemplates the viability of retrofitting (Crowley et al., 2014). Specific calculations in the risk model run on the output from a mixture of the: hazard component, exposure model, fragility model and vulnerability model. Based on the differing scenarios currently available in OpenQuake outputs include: loss statistics, loss maps, damage distribution estimates, collapse maps, loss exceedance curves, retrofitting benefit/cost ratio maps, loss disaggregation and event loss tables (Crowley et al., 2014). These output products would enable improved quantification of potential optimal immediate aid sites based on enhanced identification of building damage and collapse resulting in a more accurate depiction of displaced population.

ConclusionPre-event vulnerability is an emerging discipline requiring an exposure dataset, vulnerability model and defined hazard (Pittore and Wieland, 2013). Owing to the lack of building stock data, remote sensing is poised to be an essential tool within this discipline, with the GEM

8

Page 9: Welcome to ePrints Soton - ePrints Soton€¦ · Web viewWong TH, Mansor SB, Mispan MR, Ahmad N, Sulaiman WNA (2003) Feature extraction based on object oriented analysis , Proceedings

A MACLACHLAN, E BIGGS2 and J BEVINGTON3

toolset attempting to facilitate effective decision making through improved understanding. Immediate aid sites are one of the most important factors in the immediate aftermath of a disaster, despite little research exploring potential optimal locations. Through combining an initial vulnerability assessment with building footprint extraction and aid location suitability analysis this research presents a novel insight into the potential devastation that Kathmandu could face. Future outputs from the GEM are able to directly influence policy through identification of buildings and areas at most risk from collapse, considering the earthquake specific GEM taxonomy. Identified locations can then be prioritised for structural retrofit work and aid distribution. The GEM tools enable all countries facing earthquake risk to undertake risk assessments based on common, comparable standards, improving understanding, identifying areas of concern and reducing mortality.

REFERENCESAnhorn J and Khazai B (2014) Open space suitability analysis for emergency shelter after an earthquake, Natural Hazards and Earth System Sciences Discussions, 1(2): 4263-4297

Balcik B and Beamon BM (2008) Facility location in humanitarian relief, International Journal of Logistics, 11(2): 101-121

Bhattarai K and Conway D (2010) Urban Vulnerabilities in the Kathmandu Valley, Nepal: Visualizations of Human/Hazard Interactions, Journal of Geographic Information System, 2(2): 63-84

Bilham R, Gaur VK, Molnar P (2001) Himalayan Seismic Hazard, Science, 293: 1442-1444

Blaschke T, Lang S, Lorup E, Strobl J, Zeil P (2000) Object-oriented image processing in an integrated GIS/remote sensing environment and perspectives for environmental applications, Environmental information for planning, politics and the public, 2: 555-570

Brzev S, Scawthorn C, Charleson AW, Allen L, Greene M, Jaiswal K, Silva V, (2013) GEM building taxonomy version 2, GEM Technical Report, Pavia, Italy

Chaulagain H, Rodrigues H, Silva V, Spacone E, Varum H (2015) Earthquake loss Estimation for the Kathmandu Valley, Bulletin of Earthquake Engineering, in review

Crowley H, Monelli D, Pagani M, Silva V, Weatherill G (2014) OpenQuake Engine User Instruction Manual, GEM Technical Report, Pavia, Italy

Dixit AM, Yatabe R, Dahal RK, Bhandary NP (2013) Initiatives for earthquake disaster risk management in the Kathmandu Valley, Natural Hazards, 69(1): 631-654

Ehrlich D, Kemper T, Blaes X, Soille P (2013) Extracting building stock information from optical satellite imagery for mapping earthquake exposure and its vulnerability, Natural Hazards, 68(1): 79-95

Erener A (2013) Classification method, spectral diversity, band combination and accuracy assessment evaluation for urban feature detection, International Journal of Applied Earth Observation and Geoinformation, 21: 397-408

Fernandez J, Bendimerad F, Mattingly S, Buika J (2006) Comparative analysis of disaster risk management practices in seven megacities, Proceedings of 2nd Asian Conference on Earthquake Engineering, Manila, 10-11 March, 2006, 1-21

Geiß C and Taubenböck H (2013) Remote sensing contributing to assess earthquake risk: from a literature review towards a roadmap, Natural Hazards, 68(1): 7-48

Guha-Sapir D, Vos F, Below R, Ponserre S (2011) Annual disaster statistical review 2010: The numbers and trends, Centre for Research on the Epidemiology of Disasters, 1-50

Gupta H and Gahalaut, VK (2014) Seismotectonics and large earthquake generation in the Himalayan region, Gondwana Research, 25(1): 204-213

Hu Z, Huyck C, Eguchi M, Bevington J (2014) User guide: Tool for spatial inventory data development, GEM Technical Report, Pavia, Italy

9

Page 10: Welcome to ePrints Soton - ePrints Soton€¦ · Web viewWong TH, Mansor SB, Mispan MR, Ahmad N, Sulaiman WNA (2003) Feature extraction based on object oriented analysis , Proceedings

A MACLACHLAN, E BIGGS2 and J BEVINGTON3

Indriasari V, Mahmud AR, Ahmad N, Shariff ARM (2010) Maximal service area problem for optimal siting of emergency facilities, International Journal of Geographical Information Science, 24(2): 213-230

Jaiswal K, Wald D, D’Ayala D (2011) Developing empirical collapse fragility functions for global building types, Earthquake Spectra, 27(3): 775-795

Jodran CJ, Adlam K, Laurie K, Shelley W, Bevington J (2014) User guide: Windows tool for field data collection and management, GEM Technical Report, Pavia, Italy

Kircher C, Whitman R, Holmes W (2006) HAZUS Earthquake Loss Estimation Methods, Natural Hazards Review, 7(2): 45-59

Malladi VPT (2012) Earthquake Building Vulnerability and Damage Assessment with reference to Sikkim Earthquake, 2011, Master’s Thesis, University of Twente

Mohanty A (2011) State of Environment in Kathmandu Valley, Nepal: A Special Review, Journal of the Institute of Engineering, 8(1-2): 126-137

Mück M, Taubenböck H, Post J, Wegscheider S, Strunz G, Sumaryono S, Ismail FA (2013) Assessing building vulnerability to earthquake and tsunami hazard using remotely sensed data, Natural Hazards, 68(1): 97-114

Myint, S W, Gober P, Brazel A, Grossman-Clarke S, Weng Q (2011) Perpixel vs. object-based classification of urban land cover extraction using high spatial resolution imagery, Remote Sensing of Environment, 115(5): 1145-1161

Nastev M (2013) Adapting Hazus for seismic risk assessment in Canada, Canadian Geotechnical Journal, 51(2): 217-222

Nilsson S, Sjöberg M, Kallenberg K, Larsson G (2011) Moral Stress in International Humanitarian Aid and Rescue Operations: A Grounded Theory Study, Ethics & Behavior, 21(1): 49-68

Pinho R (2012) GEM: a Participatory Framework for Open, State-of-the-Art Models and Tools for Earthquake Risk Assessment, Proceedings of the 15th World Conference on Earthquake Engineering, Lisbon, 24-28 November 2012, 1-10

Pittore M and Wieland M (2013) Toward a rapid probabilistic seismic vulnerability assessment using satellite and ground-based remote sensing, Natural Hazards, 68(1): 115-145

Ploeger SK, Atkinson GM, Samson C (2010) Applying the HAZUS-MH software tool to assess seismic risk in downtown Ottawa, Canada, Natural Hazards, 53(1): 1-20

Porter K, Hu Z, Huyck C, Bevington J (2014) User guide: Field sampling strategies for estimating building inventories, GEM Technical Report, Pavia, Italy

Rahill GJ, Ganapati NE Clérismé and JC Mukherji A (2014) Shelter recovery in urban Haiti after the earthquake: the dual role of social capital, Disasters, 38(S1): S73-S93

Rawls CG and Turnquist MA (2012) Pre-positioning and dynamic delivery planning for short-term response following a natural disaster, Socio-Economic Planning Sciences, 46(1): 46-54

Roberts S (2013) Open geographic data for disaster risk reduction in Nepal, USAID, 1-12Silva V, Crowley H, Pagani M, Monelli D, Pinho R (2013) Development of the OpenQuake engine, the Global Earthquake Model’s open-source software for seismic risk assessment, Natural Hazards, 1-19

Silva V, Crowley H, Pagani M, Modelli D, Pinho R (2014) Development of the OpenQuake engine, the Global Earthquake Model’s open-source software for seismic risk assessment, Natural Hazards, 72:1409-1427

Thapaliya R (2006) Assessing building vulnerability for earthquake using field survey and development control data: A case study in Lalitpur sub- metropolitan city, Nepal , Master’s Thesis, International Institute For Geo- Information Science And Earth observation, The Netherlands

Tucker BE (2013) Reducing Earthquake Risk, Science, 341: 1070-1072

10

Page 11: Welcome to ePrints Soton - ePrints Soton€¦ · Web viewWong TH, Mansor SB, Mispan MR, Ahmad N, Sulaiman WNA (2003) Feature extraction based on object oriented analysis , Proceedings

A MACLACHLAN, E BIGGS2 and J BEVINGTON3

Walker BB, Taylor-Noonan C, Tabbernor A, McKinnon T, Bal H, Bradley D, Schuurman N, Clague JJ (2014) A multi-criteria evaluation model of earthquake vulnerability in Victoria, British Columbia, Natural Hazards, 1-14

Wieland M, Pittore M, Parolai S, Zschau J, Moldobekov B, Begaliev U (2012) Estimating building inventory for rapid seismic vulnerability assessment: Towards an integrated approach based on multi-source imaging, Soil Dynamics and Earthquake Engineering, 36: 70-83

Wong TH, Mansor SB, Mispan MR, Ahmad N, Sulaiman WNA (2003) Feature extraction based on object oriented analysis, Proceedings of ATC 2003 Conference, Malaysia, 20–21 May 2003, 1-10

Yi W and Özdamar L (2007) A dynamic logistics coordination model for evacuation and support in disaster response activities, European Journal of Operational Research, 179(3): 1177-1193

Zhang L, Liu X, Li Y, Liu Y, Liu Z, Lin J, Shen J, Tang X, Zhang, Y, Liang W (2012) Emergency medical rescue efforts after a major earthquake: lessons from the 2008 Wenchuan earthquake, Lancet, 379: 853-861

11