Research On Personnel Safety Evacuation Of College Buildings Based On Pathfinder

In modern society,education is developing rapidly.The strength and enrollment rate of colleges have been continuously improved,and the number of students in colleges has increased significantly.This makes the roads crowded.In an emergency,a large number of personnel cannot be evacuated in time,threatening the safety of students.When a sudden disaster occurs,within a certain safety time limit,a person is still in a dangerous area from the fire source or the earthquake or other disaster escaping from the building,so it is necessary to continue to evacuate to the safe area or shelter.In this process,personnel will make different choices for the final shelter due to the interference of psychology,physiology and surrounding environment.This requires managers to predict the characteristics and laws of the disaster impact and delimit the designated evacuation concentration area.In this paper,the factors affecting safety behavior are studied by means of questionnaire.Then,starting from the rapid evacuation characteristics of the stairwell in the simulation building,the real exercise experiment is carried out,the effectiveness of the model is verified by using real data,the simplified BIM model of campus scene is constructed,and the regional evacuation of buildings is simulated by Pathfinder,which provides a path planning tool,thought and method for safe evacuation of campus buildings.The main results are as follows:(1)A questionnaire survey was conducted among 4531 students from a private university in northwest China.The questionnaire involves eight basic information,including gender,education background,grade,hometown,one-child policy,major,community,and driver’s license,and sets 39 questions.Considering the influence of students’ different personal basic information factors on their safety behavior.The results show that according to the average score of each item,the students’ safety knowledge score is low,and the score of traffic safety behavior is high.Gender,hometown,one-child policy,major,community,driver’s license has a significant impact on safety awareness and behavior.Female student has better safety beliefs and safety behaviors than male student whilst the safety beliefs and safety behaviors of the student majoring in medicine students is better than that of students in other majors.The community system under mixed majors improves the deficiencies of some major students in safety behaviors,indicating that the later management is conducive to the formation of better safety behaviors.Questionnaire survey shows that college students’ educational background and grade have no significant effect on their safety awareness and safety behavior.Safety behavior will directly affect the evacuation time.According to the specific proportion of men and women in colleges,professional distribution and other actual situations,we should formulate corresponding intervention strategies to prevent college students’ safety accidents.(2)The visibility control experiment of single person descending was carried out under four different stair forms.The change rule of single-person evacuation time under the synergistic effect of stair type and visibility,and the behavior characteristics of personnel in the evacuation process were studied.After verifying the effectiveness of the simulation evacuation model,the internal physical mechanisms of four trapezoids under emergency evacuation are simulated.Under the influence of safety behavior on evacuation time,the influence of gender factor on emergency evacuation time in stairwell was simulated.The main conclusions are as follows.In the process of single-person downward evacuation,the evacuation time of girls is longer than that of boys.Under the condition of wearing glasses,the change of downward evacuation with the increase of floor is not obvious.Straight running with platform stairs and double parallel stairs than double parallel stairs and corner stairs evacuation pressure is smaller,less congestion.In emergency evacuation,the pressure on the platform of the stairs is small,and the front segment of the stairs and the corner part of the stairs,namely the connection between the stairs and the platform,are weak parts in emergency evacuation,which are prone to congestion.Based on the research in Chapter 2,under the influence of gender factors,since the reaction time of boys is longer than that of girls,the smaller the proportion of boys is,the smaller the time growth rate considering the reaction time is.But as the population density increases,the impact of reaction time will become smaller.(3)The basic model is constructed by BIM technology and imported into the simulation evacuation software Pathfinder to simulate the regional evacuation of university buildings.According to the selection principle of shelters,five shelters are selected on the university campus.The regional simulation model of university was established for evacuation simulation,and the reaction time of personnel parameters was set as follows: the basic reaction time of boys was 5 s and the basic reaction time of girls was 2 s according to the gender factors of safety behavior investigated in the questionnaire.Based on the results measured in the evacuation experiment,the average speed of the personnel in the stairwell was taken as the average speed of the experiment,which was set as 2.0 m/s for boys and 1.5m/s for girls.The selection and optimization of evacuation scheme for high-density campus buildings in three periods are solved.In 9:30/17:00(class time)period,based on the original evacuation scheme of colleges,an increase in shelters and diversion are formulated to solve the problem of evacuation of export congestion.The new optimization scheme is 74.5 s faster than the original evacuation scheme.At 12:30(eating time)and 22:00(sleeping time),two schemes were taken for evacuation simulation,and the optimal scheme was selected according to the evacuation time.It provides a safe evacuation path planning template for campus regional evacuation,and lays the foundation for the management level of safe evacuation.