Ancient Building Fire Risk Based On Multi-level Extension Method Evaluation Study

Most of the ancient buildings in China are wooden or brick structures.Due to years of natural erosion,low moisture content,poor fire resistance,and the large-scale development and utilization of these buildings in recent years,these ancient buildings have a lot of fire hidden dangers,the causes of fire are complex;In the event of a fire,great damage will result.Therefore,in order to reduce the frequency of fire in ancient buildings,even to prevent the occurrence of fire accidents,and to help ancient building management units to control the occurrence of fire in advance,it is particularly important to evaluate the fire risk of ancient buildings.Based on the analysis of the fire danger,characteristics and causes of ancient buildings,and the summary of fire safety situation of ancient buildings according to the current fire situation of ancient buildings,a fire risk evaluation index system and an evaluation model for evaluating the fire risk of ancient buildings are established,and the measures to reduce the fire risk of ancient buildings are put forward according to the evaluation results.The research contents and achievements of this paper are mainly as follows:(1)Considering the current situation of fire safety of ancient buildings,and according to the relevant standards and norms,a fire risk evaluation index system of ancient buildings is established.The system has 5 first-level indicators,17 secondary indicators and 43 third-level indicators,covering aspects such as the characteristics of ancient buildings,fire hazard sources,fire fighting facilities and equipment,fire rescue capacity,fire safety management,and so on.In addition,the paper analyzes the connotation of the index system and formulates the quantitative criteria of the evaluation index.(2)After comparing various comprehensive evaluation methods,this paper determines the multi-level extendable evaluation method as a fire risk assessment method for ancient buildings;the weight of fire risk assessment index of ancient buildings is obtained by entropy method,and the multi-level extendable model of fire risk assessment of ancient buildings is established.This evaluation model was used to evaluate the fire risk of Daxiong Palace,and a fire risk investigation was carried out before the fire risk assessment.The results of the investigation were shown by the building information model(BIM).After the four-level extension evaluation,it was determined that the fire risk level of Daxiong Palace is Grade 3 and its fire risk moderate.An analysis of Daxiong Palace according to the five first-level indexes revealed that Daxiong Palace needs to be further improved in terms of fire hazard sources and fire fighting facilities in order to reduce its fire risk level.(3)An automatic alarm and fire extinguishing system for ancient buildings is designed for ancient buildings similar to Daxiong Palace,which have no proper automatic fire-fighting system.This realizes the complete automation of the fire-fighting process:from the fire detection,the automatic alarm to the personnel evacuation,the fire-fighting,improves the ability to extinguish the primary fire,and minimizes the loss of life and property caused by the fire;this also provides new technology and new means to prevent and extinguish fire in ancient buildings.