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risk:detailed_exposure:risk_chile [2015/12/23 20:00]
Matias Hube
risk:detailed_exposure:risk_chile [2016/04/21 10:26] (current)
Catalina Yepes [Reposition costs]
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-**//​__...page under construction ​...__//**+**//​__...page under review ​...__//**
  
 ====== Exposure Model for Chile====== ====== Exposure Model for Chile======
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 The main economic activities of the country are copper mining, agriculture,​ fishing, and forestry. ​ The main economic activities of the country are copper mining, agriculture,​ fishing, and forestry. ​
  
-^ Region ​     ^ Inhabitants ​      ​^ Surface (km²) ​ ^+ Region ​  Inhabitants ​  Surface (km²) ​ ^
 | XV - Arica y Parinacota ​  ​| ​ 235,​081| ​ 16,873| | XV - Arica y Parinacota ​  ​| ​ 235,​081| ​ 16,873|
 | I - Tarapacá ​  ​| ​ 328,​782| ​ 42,226| | I - Tarapacá ​  ​| ​ 328,​782| ​ 42,226|
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 {{ :​risk:​detailed_exposure:​chile_macroregions.jpg?​600|}} {{ :​risk:​detailed_exposure:​chile_macroregions.jpg?​600|}}
- 
  
 Two different approaches are described to construct an exposure model for Chile: using statistical data to construct a national exposure model for the whole country, and using remote digital surveys to construct a detailed exposure model for three specific cities. The latter was done to validate the national exposure model as this model was built with information obtained from census data and other public databases. Two different approaches are described to construct an exposure model for Chile: using statistical data to construct a national exposure model for the whole country, and using remote digital surveys to construct a detailed exposure model for three specific cities. The latter was done to validate the national exposure model as this model was built with information obtained from census data and other public databases.
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 The description of the 18 typologies for the exposure models in Chile and the related GEM taxonomies are: The description of the 18 typologies for the exposure models in Chile and the related GEM taxonomies are:
  
-^ Typology number ​     ^ Description ​      ​^ GEM Taxonomy ​ ^ + Typology number ​  Description ​  GEM Taxonomy ​ ^ 
-|1|Reinforced concrete, 1-3 story houses|CR/​LWAL/​HBET:​1,​3/​RES+RES1| +  |Reinforced concrete, 1-3 story houses|CR/​LWAL/​HBET:​1,​3/​RES+RES1| 
-|2|Reinforced concrete, 3-9 story buildings|CR/​LWAL/​HBET:​3,​9/​RES+RES2| +  |Reinforced concrete, 3-9 story buildings|CR/​LWAL/​HBET:​3,​9/​RES+RES2| 
-|3|Reinforced concrete, 10-24 story buildings|CR/​LWAL/​HBET:​10,​24/​RES+RES2| +  |Reinforced concrete, 10-24 story buildings|CR/​LWAL/​HBET:​10,​24/​RES+RES2| 
-|4|Reinforced concrete, 25 or more story buildings|CR/​LWAL/​HBET:​25,​40/​RES+RES2| +  |Reinforced concrete, 25 or more story buildings|CR/​LWAL/​HBET:​25,​40/​RES+RES2| 
-|5|Unreinforced clay brick masonry, 1-2 story houses|MUR+CLBRS+MOC/​LWAL/​HBET:​1,​2/​RES+RES1| +  |Unreinforced clay brick masonry, 1-2 story houses|MUR+CLBRS+MOC/​LWAL/​HBET:​1,​2/​RES+RES1| 
-|6|Reinforced clay brick masonry, 1-2 story houses|MR+CLBRH+RS+MOC/​LWAL/​HBET:​1,​2/​RES+RES1| +  |Reinforced clay brick masonry, 1-2 story houses|MR+CLBRH+RS+MOC/​LWAL/​HBET:​1,​2/​RES+RES1| 
-|7|Reinforced clay brick masonry, 3 story buildings|MR+CLBRH+RS+MOC/​LWAL/​HEX:​3/​RES+RES2| +  |Reinforced clay brick masonry, 3 story buildings|MR+CLBRH+RS+MOC/​LWAL/​HEX:​3/​RES+RES2| 
-|8|Reinforced clay brick masonry, 4-5 story buildings|MR+CLBRH+RS+MOC/​LWAL/​HBET:​4,​5/​RES+RES2| +  |Reinforced clay brick masonry, 4-5 story buildings|MR+CLBRH+RS+MOC/​LWAL/​HBET:​4,​5/​RES+RES2| 
-|9|Confined clay brick masonry, 1-2 story houses|MCF+CLBRS+MOC/​LWAL/​HBET:​1,​2/​RES+RES1|+  |Confined clay brick masonry, 1-2 story houses|MCF+CLBRS+MOC/​LWAL/​HBET:​1,​2/​RES+RES1|
 |:::​|:::​|MCF+CLBRH+MOC/​LWAL/​HBET:​1,​2/​RES+RES1| |:::​|:::​|MCF+CLBRH+MOC/​LWAL/​HBET:​1,​2/​RES+RES1|
-|10|Confined clay brick masonry, 3 story buildings|MCF+CLBRS+MOC/​LWAL/​HEX:​3/​RES+RES2|+ 10  |Confined clay brick masonry, 3 story buildings|MCF+CLBRS+MOC/​LWAL/​HEX:​3/​RES+RES2|
 |:::​|:::​|MCF+CLBRH+MOC/​LWAL/​HEX:​3/​RES+RES2| |:::​|:::​|MCF+CLBRH+MOC/​LWAL/​HEX:​3/​RES+RES2|
-|11|Confined clay brick masonry, 4-5 story buildings|MCF+CLBRS+MOC/​LWAL/​HBET:​4,​5/​RES+RES2|+ 11  |Confined clay brick masonry, 4-5 story buildings|MCF+CLBRS+MOC/​LWAL/​HBET:​4,​5/​RES+RES2|
 |:::​|:::​|MCF+CLBRH+MOC/​LWAL/​HBET:​4,​5/​RES+RES2| |:::​|:::​|MCF+CLBRH+MOC/​LWAL/​HBET:​4,​5/​RES+RES2|
-|12|Reinforced or confined concrete block masonry, 1-2 story houses|MCF+CBH+MOC/​LWAL/​HBET:​1,​2/​RES+RES1|+ 12  |Reinforced or confined concrete block masonry, 1-2 story houses|MCF+CBH+MOC/​LWAL/​HBET:​1,​2/​RES+RES1|
 |:::​|:::​|MR+CBH+RS+MOC/​LWAL/​HBET:​1,​2/​RES+RES1| |:::​|:::​|MR+CBH+RS+MOC/​LWAL/​HBET:​1,​2/​RES+RES1|
-|13|Reinforced or confined concrete block masonry, 3 story buildings|MCF+CBH+MOC/​LWAL/​HEX:​3/​RES+RES2|+ 13  |Reinforced or confined concrete block masonry, 3 story buildings|MCF+CBH+MOC/​LWAL/​HEX:​3/​RES+RES2|
 |:::​|:::​|MR+CBH+RS+MOC/​LWAL/​HEX:​3/​RES+RES2| |:::​|:::​|MR+CBH+RS+MOC/​LWAL/​HEX:​3/​RES+RES2|
-|14|Reinforced or confined concrete block masonry, 4-5 story buildings|MCF+CBH+MOC/​LWAL/​HBET:​4,​5/​RES+RES2|+ 14  |Reinforced or confined concrete block masonry, 4-5 story buildings|MCF+CBH+MOC/​LWAL/​HBET:​4,​5/​RES+RES2|
 |:::​|:::​|MR+CBH+RS+MOC/​LWAL/​HBET:​4,​5/​RES+RES2| |:::​|:::​|MR+CBH+RS+MOC/​LWAL/​HBET:​4,​5/​RES+RES2|
-|15|Timber houses|W/​LWAL/​HBET:​1,​3/​RES+RES1| + 15  |Timber houses|W/​LWAL/​HBET:​1,​3/​RES+RES1| 
-|16|Emergency houses|W/​LWAL+DNO/​HBET:​1,​2/​RES| + 16  |Emergency houses|W/​LWAL+DNO/​HBET:​1,​2/​RES| 
-|17|Adobe houses|MUR+ADO+MOM/​LWAL+DNO/​HBET:​1,​2/​RES+RES1| + 17  |Adobe houses|MUR+ADO+MOM/​LWAL+DNO/​HBET:​1,​2/​RES+RES1| 
-|18|Informal or self-construction housing|MATO/​LWAL+DNO/​HBET:​1,​2/​RES+RES6|+ 18  |Informal or self-construction housing|MATO/​LWAL+DNO/​HBET:​1,​2/​RES+RES6|
  
 To access to the complete report of the Exposure Model for Chile called //Exposure Model: Buildings typology distribution at the census block level and replacement costs// click in the following link: To access to the complete report of the Exposure Model for Chile called //Exposure Model: Buildings typology distribution at the census block level and replacement costs// click in the following link:
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 //__2002 Census__// //__2002 Census__//
  
-Data from the 2002 census ​with a census block resolution is available at request from the National Institute of Statistics (INE, http://​www.ine.cl/​). Census-blocks are the smallest subdivisions of a municipality for census purposes. The census is a nationwide dwelling-per-dwelling survey, and the information is obtained from the response of a dwelling owner or an adult responsible of answering the survey. Therefore, non-experts provide technical information of the dwelling, such as exterior walls material. Since census data is collected per dwelling, it is easy to relate it to a structure when the dwelling is a house (usually, one house corresponds to one dwelling), but poses a major difficulty to relate dwellings in apartment buildings to a structure. Neither the number of stories per building nor the number of apartments per story are registered in the census. Hence, assumptions are required to relate dwellings to structures. The following data from the 2002 census was used to build the exposure model:+Data from the 2002 Census ​with a census block resolution is available at request from the National Institute of Statistics (INE, http://​www.ine.cl/​). Census blocks are the smallest subdivisions of a municipality for census purposes. The census is a nationwide dwelling-per-dwelling survey, and the information is obtained from the response of a dwelling owner or an adult responsible of answering the survey. Therefore, non-experts provide technical information of the dwelling, such as exterior walls material. Since census data is collected per dwelling, it is easy to relate it to a structure when the dwelling is a house (usually, one house corresponds to one dwelling), but poses a major difficulty to relate dwellings in apartment buildings to a structure. Neither the number of stories per building nor the number of apartments per story are registered in the census. Hence, assumptions are required to relate dwellings to structures. The following data from the 2002 census was used to build the exposure model:
   * location of the dwelling (census-block location with urban or rural classification)   * location of the dwelling (census-block location with urban or rural classification)
   * type of dwelling (house, apartment in building, emergency house, informal house, or other)   * type of dwelling (house, apartment in building, emergency house, informal house, or other)
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 ====Number of structures==== ====Number of structures====
  
-The number of structures per typology of the National Exposure Model was calculated ​using a combination of the 2002 Census, the UESF, and the 2012 Census. +The number of structures per typology of the National Exposure Model was estimated ​using a combination of the 2002 Census, the UESF, and the 2012 Census. 
-The proposed methodology uses the 2002 Census information to obtain the total number of dwellings per census block up to the year 2002. The key aspect of the methodology is to relate dwelling information from 2002 Census with the 18 proposed structures typologies. To assess ​this relationship, ​statistical information from the UESF is extrapolated to dwellings built prior to 2002. Story distribution (percentages) for masonry and reinforced concrete buildings, building technology and masonry unit type distribution for masonry structures are extrapolated to Census 2002 data. + 
-From 2002 to 2014, the proposed methodology uses the UESF data to estimate the number of structures for each building typology to complete the inventory. Since the UESF is available at communal level, the number of structures per typology at a commune was uniformly distributed in the 2002 census blocks. ​When there was no information available in the UESF data for a certain commune and a certain type of structure, the distribution at the regional level is considered to distribute the existing dwellings prior to 2002 in that particular commune. If there is no information available at the regional level in the UESF data, then the national ​average ​is considered for that particular commune.+The proposed methodology uses the 2002 Census information to obtain the total number of dwellings per census block up to the year 2002. The key aspect of the methodology is to relate dwelling information from 2002 Census with the 18 proposed structures typologies. To establish ​this relationship,​ the story distribution (percentages) ​from UESF data for masonry and reinforced concrete buildings, building technology and masonry unit type distribution for masonry structures are extrapolated to Census 2002 data. 
 + 
 +For structures built from 2002 to 2014, the proposed methodology uses the UESF data to estimate the number of structures for each building typology to complete the inventory. Since the UESF is available at communal level, the number of structures per typology at a commune was uniformly distributed in the 2002 census blocks. ​If there was no information available in the UESF data for a certain commune and a certain type of structure, the distribution at the regional level is considered to distribute the existing dwellings prior to 2002 in that particular commune. If there is no information available at the regional level in the UESF data, then the national ​distribution ​is considered for that particular commune. 
 The 2012 Census is used to estimate the number of emergency and informal houses, because these housing types are not thought as permanent. As this Census has the information at communal level, the total number of these types of dwellings per commune was uniformly distributed throughout the 2002 census blocks in that commune. The 2012 Census is used to estimate the number of emergency and informal houses, because these housing types are not thought as permanent. As this Census has the information at communal level, the total number of these types of dwellings per commune was uniformly distributed throughout the 2002 census blocks in that commune.
  
-The methodology to estimate the number of masonry and reinforcend concrete buildings, and masonry houses is explained in sections 2.2.1, 2.2.2, and 2.2.3 of the //Exposure Model: Buildings typology distribution at the census block level and replacement costs// report, respectively. Appendix A, B and C of the report present examples to obtain estimated number of masonry buildings, reinforced concrete buildings and masonry houses in certain communes, respectively. The aforementioned sections and appendixes are included below. For reinforced concrete, timber and adobe houses the methodology to estimate the number of houses is similar to the methodology used for masonry houses.+The methodology to estimate the number of masonry and reinforcend concrete buildings, and masonry houses is explained in sections 2.2.1, 2.2.2, and 2.2.3 of the //Exposure Model: Buildings typology distribution at the census block level and replacement costs// report, respectively. Appendix A, B and C of the report present examples to obtain estimated number of masonry buildings, reinforced concrete buildings and masonry houses in certain communes, respectively. For reinforced concrete, timber and adobe houses the methodology to estimate the number of houses is similar to the methodology used for masonry houses. The aforementioned sections and appendixes are included below.
  
 {{:​risk:​detailed_exposure:​section_2.2.1_number_of_masonry_buildings.pdf|}} {{:​risk:​detailed_exposure:​section_2.2.1_number_of_masonry_buildings.pdf|}}
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 {{:​risk:​detailed_exposure:​appendix_c_example_for_masonry_houses.pdf|}} {{:​risk:​detailed_exposure:​appendix_c_example_for_masonry_houses.pdf|}}
  
-====Surface built==== +====Occupants per typology==== 
-====Reposition ​costs====+ 
 +The average occupants per type of dwellings (i.e. RC apartments, RC houses, masonry apartments, masonry houses, timber houses, adobe houses, emergency houses and informal housing) in each commune was obtained using 2012 Census data. Then, the total occupants per typology can be estimated by multiplying this average with the number of dwellings of the exposure model. 
 + 
 +====Floor area per typology==== 
 + 
 +The average floor area for structures of each typology was estimated using UESF data for each commune, because census data does not provide information on floor areas of dwellings. For multi-story buildings, the average floor area considers the built area of all stories. For emergency timber houses, and for informal houses an average floor area is not estimated because the total cost of these structures are estimated directly with the number of structures. 
 + 
 +====Replacement ​costs per typology==== 
 + 
 +Ministry of Housing and Urbanism (MINVU) defines the costs per unit of area for five quality categories of residential structures: from superior to inferior. 
 + 
 +For the National Exposure Model, it is not possible to calculate the category for each structure based on any of the statistical data used. Typical structures were considered for the main building materials (reinforced concrete, masonry, timber and adobe), and it was possible to establish the best and worst qualities for each type of structure with its replacement costs related. 
 + 
 +As the communes in the whole country does not have the same replacement costs, it is necessary to differentiate costs between them. The Internal Revenue Service (SII) has information of base appraisal values for residential structures with the same five categories than MINVU. This base appraisal value is modified by four factors dependent on the structure’s location, special conditions of the structure, depreciation,​ and a commercial coefficient applicable to structures built in commercial zones. The factor that depends on the structure’s location is assigned for each commune, from 1.0 to 0.4. To estimate the replacement cost of structures in each commune, the cost associated to best quality of construction was assumed for structures in communes with factor 1.0, and the cost associated to worst quality of construction was assumed in communes with factor 0.4. For other communes, the replacement cost is extrapolated according to its factor. 
 + 
 +Replacement cost for emergency and informal houses are not defined by MINVU. Then, it was assumed to be the same as the construction cost of a new emergency house: an average of USD 1,280. Replacement costs for informal houses are considered the same as for emergency houses because after an earthquake, damaged informal houses would be replaced with emergency houses by the authorities or helping institutions.
  
 =====Results===== =====Results=====
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 [[national_exp_model_chile_surface| here]] [[national_exp_model_chile_surface| here]]
  
-====Reposition ​costs==== +====Replacement ​costs==== 
-More than **108 billion USD** corresponds to the total reposition ​cost for all the residential structures in Chile. The participation of the reposition ​cost per typology is:+More than **108 billion USD** corresponds to the total replacement ​cost for all the residential structures in Chile. The participation of the replacement ​cost per typology is:
  
 {{ :​risk:​detailed_exposure:​chile_costo_total_tipologias.png?​800 |}} {{ :​risk:​detailed_exposure:​chile_costo_total_tipologias.png?​800 |}}
  
-To see more detailed information about the reposition ​costs per typology click+To see more detailed information about the replacement ​costs per typology click
 [[national_exp_model_chile_costs| here]] [[national_exp_model_chile_costs| here]]
  
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 ======Detailed Exposure Model====== ======Detailed Exposure Model======
  
 +In this section, the methodology used to build the Detailed Exposure Model for three representative cities from three different macro-regions in Chile, and the results of this model are presented.
 =====Methodology===== =====Methodology=====
 +
 +This section describes the methodology used to obtain a Detailed Exposure Model for three cities (urban zones of three communes) in Chile using digital remote surveying, similar to a residential housing census, to count and classify structures using the 18 typologies of the Exposure Model. The three cities were chosen to be representative of three macro-regions of Chile: Iquique for the Great North of the country, Rancagua for Central Zone, and Osorno for the Southern Zone. 
 +
 +The city Iquique, located in the Iquique commune is the capital of the I Region of Tarapacá, and is located in the coastal plain at latitude 20.22°S, almost 1,800 km north of Santiago. The commune of Iquique has a total surface of 2,262 km2 and 196,437 inhabitants (SINIM, 2015).
 +
 +Rancagua is the main city and capital of the VI Region of Libertador Bernardo O’Higgins;​ it is located in the central valley at latitude 34.17°S, approximately 85 km south of Santiago. It is located in the commune of Rancagua, one of the most important and most populated communes in Central Chile. In 2014, the commune had 232,639 inhabitants and a surface of 260 km2 (SINIM, 2015).
 +
 +Osorno is the second most important city in the X Region of Los Lagos, and is located at latitude 40.57°S, more than 800 km south of Santiago. It is located in the commune of Osorno, which by 2014 had 157,389 inhabitants and a surface of 951 km2.
 +
 +The following figure shows the location of the cities of Iquique, Santiago, Rancagua, and Osorno in a map of Chile.
  
 {{:​risk:​detailed_exposure:​chile_mapa_tres_ciudades.png?​600 |}} {{:​risk:​detailed_exposure:​chile_mapa_tres_ciudades.png?​600 |}}
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 ====Performance of the remote surveying==== ====Performance of the remote surveying====
  
-^      ^ Iquique ​     ^ Rancagua ​ ^ Osorno ​ ^+^      ^  Iquique ​  Rancagua ​ ^  Osorno ​ ^
 |Total surface (km²)| ​ 18.5|  46.2|  29.0| |Total surface (km²)| ​ 18.5|  46.2|  29.0|
 |Covered surface (km²)| ​ 14.4|  34.4|  22.0| |Covered surface (km²)| ​ 14.4|  34.4|  22.0|
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-{{ :​risk:​detailed_exposure:​iquique_estructuras_modelos_3.jpg?1100 |}}+{{ :​risk:​detailed_exposure:​iquique_estructuras_modelos_3.jpg |}}
 {{ :​risk:​detailed_exposure:​leyenda_graficos_2.png?​1000 |}} {{ :​risk:​detailed_exposure:​leyenda_graficos_2.png?​1000 |}}
  
 ===Rancagua=== ===Rancagua===
  
- +{{ :​risk:​detailed_exposure:​rancagua_estructuras_modelos_3.jpg |}}
-{{ :​risk:​detailed_exposure:​rancagua_estructuras_modelos_3.jpg?850 |}}+
 {{ :​risk:​detailed_exposure:​leyenda_graficos_2.png?​1000 |}} {{ :​risk:​detailed_exposure:​leyenda_graficos_2.png?​1000 |}}
  
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 ===Osorno=== ===Osorno===
  
- +{{ :​risk:​detailed_exposure:​osorno_estructuras_modelos_3.jpg |}}
-{{ :​risk:​detailed_exposure:​osorno_estructuras_modelos_3.jpg?1350 |}}+
 {{ :​risk:​detailed_exposure:​leyenda_graficos_2.png?​1000 |}} {{ :​risk:​detailed_exposure:​leyenda_graficos_2.png?​1000 |}}
  
-[[detailed_exp_model_chile_structures|... ​see more detailed information about the number of structures per typology]]+To see more detailed information about the number of structures per typology ​in Iquique, Rancagua and Osorno, click  
 +[[detailed_exp_model_chile_structures|here]]
  
 **//​__...page under construction ...__//** **//​__...page under construction ...__//**
  
  • risk/detailed_exposure/risk_chile.1450897205.txt.gz
  • Last modified: 2015/12/23 20:00
  • by Matias Hube