清华大学学报（自然科学版）2025，Vol.65Issue(4)：625-633,9.DOI:10.16511/j.cnki.qhdxxb.2024.27.027
古建筑群室外图像型火灾探测器布置优化研究
Optimal placement of outdoor image fire detectors in historic buildings
摘要
Abstract
[Objective]Most historic buildings in China wood or brick-wood structures;consequently,they have low fire resistance ratings and large fire loading values.Furthermore,firefighting problems associated with these buildings include high building density,insufficient fire separation distances,and narrow fire passages;thus,historical buildings face a high risk of damage owing to fire.Therefore,to prevent and control fires in historical buildings,exploring efficient early fire detection and alarm systems for these buildings is necessary.Image fire detectors enable rapid identification of fires and provide the location of fires;thus,they are used in early fire detection and alarm systems for historic buildings.However,there is a lack of study that accurately calculate the coverage and evaluated the placement of image fire detectors.Currently,the placement of outdoor image fire detectors depends on semiquantitative approaches such as engineers'experiences and existing regulations.[Methods]Consequently,this study proposes a placement optimization methodology for outdoor image fire detectors in historical buildings based on the set covering and maximum covering models.First,a three-dimensional model of the target area is constructed by integrating the structural information of historical buildings and mesh division.Second,the field of view of an image fire detector is determined based on its models and specifications to analyze its viewshed;subsequently,a set of candidate detector positions is constructed using the selection rule that selects more important areas and less occluded areas,thus providing support for the reasonable placement of image fire detectors.Furthermore,the extent of coverage of the target area grid by the candidate detectors is determined by constructing a binary observation matrix that maps the position and direction of image fire detectors in the target area.Third,considering the optimization of the cost and coverage of image fire detectors as the goal,a mathematical model for the placement optimization of image fire detectors is developed based on the set covering model and maximum covering model.Finally,based on the genetic algorithm,the optimal placement scheme of image fire detectors is obtained using the previously constructed placement optimization model.[Results]To demonstrate the feasibility and effectiveness of the proposed methodology,this study considers the joint area composed of the Hall of Supreme Harmony,Hall of Central Harmony,and Hall of Preserving Harmony of The Imperial Palace as a case study.Under the given target area coverage and predetermined cost,the optimal placement plan of image fire detectors is obtained,i.e.,｛11,13,16,20,23,25,33,35,48,55,58,60,62,64,67,68｝ and ｛11,22,26,29,35,44,48,59,64,67｝.In addition,the joint area coverage reached 98.17％and 92.41％,respectively.[Conclusions]Compared with the existing semiquantitative approaches to placing image fire detectors,the proposed methodology simplifies several manual calculation processes and can meet different requirements for cost and coverage within the detection area,thus optimizing the placement of image fire detectors.In addition,this methodology can quickly and accurately obtain the position and direction of the detector,which can be used for installing and calibrating outdoor image fire detectors in historical buildings.Thus,the proposed methodology can be implemented in the construction of early fire detection and alarm system in historical buildings to prevent massive economic and cultural losses owing to fire damage.关键词
古建筑群/火灾探测/图像型火灾探测器/布置优化Key words
historical buildings/fire detection/image fire detectors/placement optimization分类
建筑与水利引用本文复制引用
马强,蒋弘瑞,王可,王波,丁龙,纪杰..古建筑群室外图像型火灾探测器布置优化研究[J].清华大学学报（自然科学版）,2025,65(4):625-633,9.基金项目
国家重点研发计划项目(2021YFC1523500) （2021YFC1523500）
