Atlantis Press Journal style Received 26 September 2015 Accepted 20 January 2016 High-rise Building Group Regional Fire Risk Assessment Model Based on AHP Wei Zhu, Qiuju You Beijing Research Center of Urban Systems Engineering, Beijing 100035, P.R. China Beijing Key Laboratory of Operation Safety of Gas, Heating and Underground Pipelines, Beijing 100035, P.R. China E-mail: zhuweianquan@126.com, yqjbyq@163.com Abstract Based on Analytic Hierarchy Process (AHP), a regional fire risk assessment model is developed for high-rise building group considering the fire danger degree, basic characters of the high-rise building group and fire control capability. The impact factors, values of typical risk parameter and the weight of each index are analyzed. An assessment program is further developed using Matlab, to perform the risk assessment procedures. The model is then applied to the regional fire risk evaluation of a high-rise building group. Keywords: High rise building, Fire, Risk assessment, AHP 1. Introduction With the development of city construction and the increase of population density, land is becoming a limited resource. In order to overcome the problem, more and more high-rise buildings are built. High-rise building fires have many special characteristics, such as the diversity of blazing, factors, various ways of fires spreading, the difficulty of evacuation and saving activities. Due to the importance of fire safety for the high-rise building, many studies have been conducted to analyze the fire risk of the high-rise building. Chen et al.(Chen et al. 2012) has analyzed the fire accident using the accident tree analysis method and the principal theory of safety system engineering. Liu et al.(Liu et al. 2012) has analyzed the factors that can cause high-rise building fires, and a partial event tree has been built. Sun et al.(Sun & Luo, 2014) has madea case study for a super high-rise building to expatiate the procedure and methodology of fire risk assessment for super high-rise buildings. Cowlard et al.(Cowlardet al.2013) has made some studies on the fire safety design for tall buildings. For a high-rise building group in a community, the fire safety is more important. Because of the complex of itself, such as more high-rise buildings, limited spacing between buildings, once a fire happened, fire spreading may arise. As a typical disaster in urban public safety, high-rise building group fire should attract more attention and be treated seriously. However, very limited work has been reported for fire risk assessment of high-rise building group. Here, based on the characteristic of high-rise building group, Analytic Hierarchy Process (AHP) is used to develop a regional fire risk assessment model for high-rise building group. As a risk assessment method, AHP has been used by many researchers in evaluation of fire risk, see (Wang et al.2012; Ren,2012; Zhang, 2013; Gao, 2014; and Omidvariet al. 2015) for more details. Then the model is applied to the fire risk evaluation of a high-rise building group. 2. Analytic Hierarchy Process The first step of AHP is to establish AHP structure index system. The AHP structure index system can be divided into several layers according to the influence factors, and the first layer only has one factor. After that the structure judgment matrix should be built. For the factors which are below a same upper factor are compared with each other to confirm the weights of each factors for the same upper factor based on Table 1, and then the structure judgment matrix is obtained as Eq. (1). 11 12 1 21 22 2 1 2 3 ⋅ ⋅ ⋅   ⋅ ⋅ ⋅ =  ⋅ ⋅ ⋅ ⋅ ⋅ ⋅ ⋅ ⋅ ⋅ ⋅ ⋅ ⋅     n n n n n nn a a a a a a A a a a a (1) Journal of Risk Analysis and Crisis Response, Vol. 6, No. 1 (April 2016), 31-37 Published by Atlantis Press Copyright: the authors 31 Wei Zhu and Qiuju You / Building Group Fire Risk whereaij is the result, n is the number of factors. Obviously, aij>0, aii=1, and aij=1/aji. In order to obtain the weight of each index, the eigenvector and the latent root of matrix should be counted, and the sum and product method is used as shown below. maxλ=Aw w (2) wherew is the eigenvector,λmaxis the latent root of matrix, and they can be calculated as 1 1 1 1, 2, ,= = = = = ⋅ ⋅ ⋅ ∑ ∑ ∑ ij j i n n kj k j a w i n a (3) ( ) max 1 λ = = ∑ n i i i Aw nw (4) Then the consistency of the matrix should be tested with the index CR, = CI CR RI (5) max 1 λ − = − n CI n (6) and the value of RI is shown in Table 2 for different matrix order. Table 2. RI for different matrix order order 1 2 3 4 5 6 7 RI 0 0 0.58 0.90 1.12 1.24 1.32 If CR<0.10, the consistency of judgment matrix is good and the eigenvector is the weight of each index, or, the judgment matrix should be rebuilt. 3. A fire risk assessment model for high-rise building group region 3.1 Comprehensive assessment factors Based on the causes of high-rise building group, the comprehensive factors are shown in Fig 1. The hierarchical model is divided into four layers. The first layer is the target layer, and the only factor was fire risk of high-rise building group. The second and third layer were criterion layers, the second layer include five factors. Every factor contains its subset of indicators. The last layer is index layer, and the model includes twenty five indexes. 3.2Weight of each factors According to the hierarchical model (Fig. 1), the judgment matrix can be built. Based on Table 1, the results of the pair-wise comparison of the target layer are expressed as Eq.7. And using Eqs. 2-4, the weight of each factors in second layer Ua, Ub, Uc, Ud, Ue is obtained w=(0.313 0.141 0.234 0.234 0.078). Here, in order to make the operation convenient, a procedure is developed using Matlab as shown in Fig. 2. 1 2 2 2 3 1 2 1 1 2 1 2 2 1 2 2 1 1 3 1 2 2 1 1 3 1 3 1 2 1 3 1 3 1        =        A (7) Table 1. Importance degree. i,j compare aij signification iis as important as j 1 iis as important as j iis a little more important than j 3 The former factor is a little more important than the latter i is obviously more important than j 5 The former factor is obviously more important than the latter iis much more important than j 7 The former factor is much more important than the latter iis extremely more important than j 9 The former factor is extremely more important than the latter - 2,4,6,8 The middle value between the above neighboring judgments Published by Atlantis Press Copyright: the authors 32 Wei Zhu and Qiuju You / Building Group Fire Risk Result of subset Ua,Ub,Uc,Ud, are shown respectively as Eqs. 8-11. And the weight of the factors in layer three is obtained, and wa=(0.4 0.2 0.4); wb=(0.297 0.257 0.057 0.178 0.112 0.099); wc=(0.065 0.218 0.262 0.105 0.175 0.175); wd=(0.072 0.339 0.589). 1 2 1 1 2 1 1 2 1 2 1    =      aA (8) 1 1 5 2 3 3 1 1 3 2 3 3 1 5 1 3 1 1 3 1 2 1 2 1 2 1 2 3 1 1 3 1 3 1 3 2 1 1 1 1 3 1 3 2 1 3 1 1         =            bA (9) 1 1 2 1 3 1 2 1 3 1 3 2 1 1 2 2 2 3 1 1 3 2 2 2 1 2 1 3 1 1 2 1 2 3 1 2 1 2 2 1 1 3 1 2 1 2 2 1 1 cA         =           (10) 1 1 5 1 7 5 1 1 3 7 3 1 dA    =      (11) Result of subset Ua1,Ua2,Ua3,Ub6, are shown respectively as Eqs. 12-15. And the weight of the factors in layer four is obtained, and wa1=(0.225 0.067 0.539 0.169); wa2=(0.833 0.167); wa3=(0.5 0.5); wb6=(0.333 0.667). 1 3 1 4 2 1 3 1 1 5 1 3 4 5 1 5 1 2 3 1 5 1      =       a1A (12) 1 5 1 5 1   =     a2A (13) 1 1 1 1   =     a3A (14) 1 1 2 2 1   =     b6A (15) According to the hierarchical model and the weight of every layer, the weight of every factor can be achieved. The characters of the buildings Ua Comprehensive fire extinguishing capability Ub Evacuation capability Uc Fire safety management Ud Others (arson, firecracker) Ue Internal condition of the building Ua1 Internal condition of the building Ua2 High risk huildings Ua3 Height of the buildings Ua11 Finishing material Ua12 Population density Ua13 Electrical aging Ua14 The spacing between adjacent buildings Ua21 Fire passage Ua22 Market Ua31 Ballroom, KTV, restaurant Ua32 Fire detecting and automatic alarm system Ub1 Fire extinguishing system Ub2 Fire elevator Ub3 Fire hydrant Ub4 Part time fire brigade Ub5 Professional fire brigade Ub6 The arriving time of fire brigade Ub61 The facility of the fire brigade Ub62 Fire compartment and smoke bay Uc1 Refuge storey Uc2 Smoke control system Uc3 Fire alarm address system Uc4 Evacuation distance Uc5 Evacuation exit and emergency exit Uc6 Fire-control publicity Ud1 Facility maintenance Ud3 Fire patrol Ud2 Fire risk of high-rise building group U Fig. 1. Fire risk assessment hierarchical model of the high-rise building group. Fig. 2. Judgment matrix and consistency. aU bU cU dU eU weight pass consistency of the matrix aU bU cU dU eU Published by Atlantis Press Copyright: the authors 33 Wei Zhu and Qiuju You / Building Group Fire Risk The weight is shown in the following W=(0.028, 0.008, 0.067, 0.021, 0.052, 0.010, 0.062, 0.062, 0.041, 0.036, 0.008, 0.025, 0.026, 0.004, 0.009, 0.015, 0.051, 0.061, 0.024, 0.040, 0.040, 0.016, 0.079, 0.137, 0.078). 3.3Comprehensive assessment model We could not quantify fire risk of the high-rise building group only based on the weight of the factors. In this study, the score of each factor of a certain high-rise building group should be determined with the aid of the expert scoring. And Table 3 shows the scoring criteria. During the assessment, each factor has a score on the basis of Table 3. And then it will be multiplied by its weight. The comprehensive score R of the high-rise building group will be obtained by the summation of all the factors. The relationship between the fire risk grades and the scale is shown detailed as follow 2 ≤R<4 low-grade risk,4 ≤R<6 moderate risk, 6 ≤R<8 high risk, 8 ≤R≤ 10super highrisk 4. Application for case study Then a high-rise building group has been selected for example. The area of the whole high-rise building group is 12.28 hectares, and the total construction area is 700000 square meters with ground floor total area of 190000 square meters. It contains 18 apartments, 2 office buildings, 4 small offices and a large number of annexes. Supporting facilities include kindergarten and club. The height of the highest building is 100m. The scores of each factors is shown in Table 4. Here, the Matlab procedure is also used to make the assessment based on the Comprehensive assessment model built in this study, and part of the assessment process is shown in Fig. 3. According to the score and weight of every factor the assessment of the fire risk of the high-rise building group can be done as shown in Fig. 3. The quantitative result of the building group is 4.85681. The fire risk grade is moderate risk. 5. Concluding Remarks Based on the Analytic Hierarchy Process (AHP), a regional fire risk assessment model is developed for high-rise building group. Fire risk assessment hierarchical model is built which contains twenty five impact factors, and the weights of each index are obtained using AHP method. Marking criterion of each factor is provided. An assessment program is further developed using Matlab, to perform the risk analysis and evaluation procedures. The model is then applied to the regional fire risk evaluation of a high-rise building group. Published by Atlantis Press Copyright: the authors 34 Wei Zhu and Qiuju You / Building Group Fire Risk Table 3. Marking criterion of each factor. 2 3 4 Factors and score Ua Ua1 Ua11(m) >100 24 -100 <24 10 6 2 Ua12 various and messy general less and organized 10 6 2 Ua13(person/km 2) >3000 1500- 3000 800- 1500 300-800 <300 10 8 6 4 2 Ua14 bad general good 10 6 2 Ua2 Ua21 nonstandard standard for main building standard 10 6 2 Ua22 congested partly occupied expedite 10 6 2 Ua3 Ua31 many and concentrate d some and slightly concentrated general less andslightly dispersed rare and dispersed 10 8 6 4 2 Ua32 many and concentrate d some and slightly concentrated general less andslightly dispersed rare and dispersed 10 8 6 4 2 Ub Ub1 broken normal running with general performance good 10 6 2 Ub2 broken normal running with general performance good 10 6 2 Ub3 ≤1or broken ≥2 ≥2 and normal running 10 6 2 Ub4 insufficient or small cover area sufficient with small cover area sufficient with adequate coverage 10 2 2 Ub5 unorganized general organized and high quality 10 6 2 Ub6 Ub61(min) ≥25 20-25 15-20 10-15 ≤10 10 8 6 4 2 Ub62 bad general good 10 6 2 Uc Uc1 ≥2times of requirement ≥requirement and ≤2times requirement standard 10 6 2 Uc2 nonstandard refugestorey but partially standard standard 10 6 2 Published by Atlantis Press Copyright: the authors 35 Wei Zhu and Qiuju You / Building Group Fire Risk Table 4. Score of each factor. Factors Score Factors Score Height of the buildings Ua11 6 Finishing material Ua12 6 Population density Ua13 10 Electrical aging Ua14 6 The spacing between adjacent buildings Ua21 6 Fire passage Ua22 6 Market Ua31 6 Ballroom, KTV, restaurant Ua32 6 Fire detecting and automatic alarm system Ub1 2 Fire extinguishing system Ub2 2 Fire elevator Ub3 2 Fire hydrant Ub4 2 Part time fire brigade Ub5 10 The arriving time of fire brigade Ub61 6 The facility of the fire brigade Ub62 6 Fire compartment and smoke bay Uc1 6 Refuge storeyUc2 2 Smoke control system Uc3 2 Fire alarm address system Uc4 2 Evacuation distance Uc5 6 Evacuation exit and emergency exit Uc6 6 Fire-control publicity Ud1 6 Fire patrol Ud2 6 Facility maintenance Ud3 6 Arson, firecracker Ue 2 Table 3. (Continued) 2 3 4 Factors and score Uc Uc3 poor performance or broken normal running with general quality good 10 6 2 Uc4 poor performance or broken normal running with general quality good 10 6 2 Uc5(m) >50 20-50 <20 10 6 2 Uc6 congested partly occupied expedite 10 6 2 Ud Ud1 bad general good 10 6 2 Ud2 unscheduled or overlooked scheduled with poor performance scheduled with good performance 10 6 2 Ud3 unscheduled or overlooked scheduled with poor performance scheduled with good performance 10 6 2 Ue arson, firecracker bad general good 10 6 2 Published by Atlantis Press Copyright: the authors 36 Wei Zhu and Qiuju You / Building Group Fire Risk Acknowledgment This research is supported by This research is supported by National Science Foundation for Distinguished Young Scholars of China (No. 11202004), National science and technology program of China (No. 2015BAK12B00), Project of BJAST (No. PXM2014-178215-000007). The authors deeply appreciate the support. References H.T. Chen, L.L. 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Zhang, Analysis on comprehensive risk assessment for urban fire: the case of Haikou city,Procedia Engineering, 52 (2013) 618-623. J.P. Gao, Z.S. Xu, D.L. Liu, H.H. Cao, Application of the model based on fuzzy consistent matrix and AHP in the assessment of fire risk of subway tunnel,Procedia Engineering, 71 (2014) 591-596. M. Omidvari, N. Mansouri, J. Nouri, A pattern of fire risk assessment and emergency management in educational center laboratories,Safety Science, 73 (2015) 34-42. Published by Atlantis Press Copyright: the authors 37 1. Introduction 2. Analytic Hierarchy Process 3. A fire risk assessment model for high-rise building group region 4. Application for case study 5. Concluding Remarks Acknowledgment References << /ASCII85EncodePages false /AllowTransparency false /AutoPositionEPSFiles true /AutoRotatePages /None /Binding /Left /CalGrayProfile (Dot Gain 20%) /CalRGBProfile (sRGB IEC61966-2.1) /CalCMYKProfile (U.S. Web Coated \050SWOP\051 v2) /sRGBProfile (sRGB IEC61966-2.1) /CannotEmbedFontPolicy /Error /CompatibilityLevel 1.4 /CompressObjects /Tags /CompressPages true /ConvertImagesToIndexed true /PassThroughJPEGImages true /CreateJobTicket false /DefaultRenderingIntent /Default /DetectBlends true /DetectCurves 0.0000 /ColorConversionStrategy /UseDeviceIndependentColorForImages /DoThumbnails false /EmbedAllFonts true /EmbedOpenType false /ParseICCProfilesInComments true /EmbedJobOptions true /DSCReportingLevel 0 /EmitDSCWarnings false /EndPage -1 /ImageMemory 1048576 /LockDistillerParams false /MaxSubsetPct 100 /Optimize true /OPM 1 /ParseDSCComments true /ParseDSCCommentsForDocInfo true /PreserveCopyPage true /PreserveDICMYKValues true /PreserveEPSInfo true /PreserveFlatness true /PreserveHalftoneInfo false /PreserveOPIComments true /PreserveOverprintSettings true /StartPage 1 /SubsetFonts true /TransferFunctionInfo /Apply /UCRandBGInfo /Preserve /UsePrologue false /ColorSettingsFile () /AlwaysEmbed [ true ] /NeverEmbed [ true ] /AntiAliasColorImages false /CropColorImages true /ColorImageMinResolution 300 /ColorImageMinResolutionPolicy /OK /DownsampleColorImages true /ColorImageDownsampleType /Bicubic /ColorImageResolution 300 /ColorImageDepth -1 /ColorImageMinDownsampleDepth 1 /ColorImageDownsampleThreshold 1.50000 /EncodeColorImages true /ColorImageFilter /DCTEncode /AutoFilterColorImages true /ColorImageAutoFilterStrategy /JPEG /ColorACSImageDict << /QFactor 0.15 /HSamples [1 1 1 1] /VSamples [1 1 1 1] >> /ColorImageDict << /QFactor 0.15 /HSamples [1 1 1 1] /VSamples [1 1 1 1] >> /JPEG2000ColorACSImageDict << /TileWidth 256 /TileHeight 256 /Quality 30 >> /JPEG2000ColorImageDict << /TileWidth 256 /TileHeight 256 /Quality 30 >> /AntiAliasGrayImages false /CropGrayImages true /GrayImageMinResolution 300 /GrayImageMinResolutionPolicy /OK /DownsampleGrayImages true /GrayImageDownsampleType /Bicubic /GrayImageResolution 300 /GrayImageDepth -1 /GrayImageMinDownsampleDepth 2 /GrayImageDownsampleThreshold 1.50000 /EncodeGrayImages true /GrayImageFilter /DCTEncode /AutoFilterGrayImages true /GrayImageAutoFilterStrategy /JPEG /GrayACSImageDict << /QFactor 0.15 /HSamples [1 1 1 1] /VSamples [1 1 1 1] >> /GrayImageDict << /QFactor 0.15 /HSamples [1 1 1 1] /VSamples [1 1 1 1] >> /JPEG2000GrayACSImageDict << /TileWidth 256 /TileHeight 256 /Quality 30 >> /JPEG2000GrayImageDict << /TileWidth 256 /TileHeight 256 /Quality 30 >> /AntiAliasMonoImages false /CropMonoImages true /MonoImageMinResolution 1200 /MonoImageMinResolutionPolicy /OK /DownsampleMonoImages true /MonoImageDownsampleType /Bicubic /MonoImageResolution 1200 /MonoImageDepth -1 /MonoImageDownsampleThreshold 1.50000 /EncodeMonoImages true /MonoImageFilter /CCITTFaxEncode /MonoImageDict << /K -1 >> /AllowPSXObjects false /CheckCompliance [ /None ] /PDFX1aCheck false /PDFX3Check false /PDFXCompliantPDFOnly false /PDFXNoTrimBoxError true /PDFXTrimBoxToMediaBoxOffset [ 0.00000 0.00000 0.00000 0.00000 ] /PDFXSetBleedBoxToMediaBox true /PDFXBleedBoxToTrimBoxOffset [ 0.00000 0.00000 0.00000 0.00000 ] /PDFXOutputIntentProfile () /PDFXOutputConditionIdentifier () /PDFXOutputCondition () /PDFXRegistryName () /PDFXTrapped /False /CreateJDFFile false /Description << /ARA /BGR /CHS /CHT /CZE /DAN /DEU /ESP /ETI /FRA /GRE /HEB /HRV (Za stvaranje Adobe PDF dokumenata najpogodnijih za visokokvalitetni ispis prije tiskanja koristite ove postavke. 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