地下多层人员密集场所多因素协同作用上行疏散速度模型研究

The occupants in a typical underground multilayer assembly occupancy must walk upstairs through the long-distance staircases to the safe zone on the ground in case of emergence. The occupant upstairs evacuation speed in the typical underground multilayer assembly occupancies is multi-factor coupling affected by travel distance, merging behavior and occupant density, visibility, luggage and etc.The multi-factor coupling upstairs evacuation speed model is one of the important and basic science issues in the research field of emergency evacuation in the typical underground multilayer assembly occupancies. Firstly, 12 long-distance upstairs evacuation experiments in a 20-storey straircase will be carried out in different conditions, then the single-factor,double-factor and multi-factor functional relationships between evacuation speed and travel distance, merging behavior and occupant density, visibility, luggage will be derived from the experimental results; secondly, the multi-factor coupling upstairs evacuation speed model will be established based on the improved multi-grid model theory;thirdly, the accuracy of evacuation speed model and egress time predicted by the established model will be validated and verified, as well as the consistency of movement trajectory and area occuppied; and at last the validated evacuation speed model will also be applied to the evacuation design and risk assessment in the underground multilayer assembly occupancy. The innovation of this research project is that a new kind of anlysis approach of video data, which can accurately caculate the movement trajectory and area occupied for each occupant, will be used to analyze the results of evacuation experiments and drills. And the "physical endurance " and other three factors used in the speed model will also dramatically improve the accuracy of model establishing and validation. The occupant evacuation speed predicted by the model is affected by the 4 factors, i.e., travel distance, merging behavior and occupant density, visibility, luggage.

地下多层人员密集场所灾时人员必须经过楼梯长距离上行疏散至地面，其疏散速度受到疏散距离、人员汇流和人员密度、能见度、行李等因素协同作用的影响，其疏散速度模型是地下多层人员密集场所应急疏散领域的关键基础科学问题之一。本课题首先开展十二组不同条件下楼梯中人员长距离上行疏散实验，然后根据实验结果建立疏散速度与疏散距离、人员汇流和人员密度、能见度和行李等单因素、双因素及多因素协同作用的函数关系，基于改进型格子气理论构建多因素协同作用上行疏散速度模型，最后对模型模拟预测的疏散速度和疏散时间的准确性，疏散轨迹和占用面积的重合率进行验证，并将验证后的模型应用于解决实际工程中的技术难题。课题主要的创新性体现在应用了可以准确还原人员疏散轨迹和占用面积的新型影像数据后处理技术，使实验数据更加准确可靠；模型构建过程中增设了“疲劳度”等4个因子，反映出多因素协同作用对上行疏散速度的影响，使模型构建与验证的精度更高。

地下多层人员密集场所灾害条件下人员必须经过楼梯长距离上行疏散至地面，其疏散速度受到疏散距离、人员汇流和人员密度、能见度、行李等因素协同作用的影响，其疏散速度模型是地下多层人员密集场所应急疏散领域的关键基础科学问题之一。.本课题首先开展不同条件下楼梯中人员长距离上行疏散实验，然后根据实验结果建立疏散速度与疏散距离、人员汇流和人员密度、能见度和行李等单因素、双因素及多因素协同作用的函数关系。研究结果表明：诸多影响上行速度的因素中，疏散距离对疏散速度有重大影响；四种能见度条件下，平均疏散速度和人口密度之间存在着很强的线性关系；疏散过程中，负载日常行李不是影响人员疏散速度的主要因素，是否负重才是群集过程中影响疏散速度的关键因素。.最后构建了多因素协同作用上行疏散速度模型，对模型模拟预测的疏散速度和疏散时间的准确性，疏散轨迹和占用面积的重合率进行验证，并将验证后的模型应用于解决重庆市沙坪坝地下综合交通枢纽工程中的疏散难题。研究结果表明：人员在恒定速度下的长距离楼梯疏散中，楼梯入口处的流量对疏散时间几乎没有影响；考虑疲劳或能见度的降低，都对人员疏散影响显著，人员疏散速度明显减慢，疏散时间明显增加；综合考虑了汇流、疲劳和能见度对楼梯长距离上行疏散的影响，考虑疲劳程度或能见度都会使汇流情况下的疏散时间明显变长；利用人员的四维轨迹坐标的偏差来验证疏散实验与模型模拟的拟合度，并通过修正疏散速度公式和模型的静态场系数，提高了模型的精度。.综上所述，本课题的研究为解决地下多层人员密集场所中人员疏散设计与评估中存在的疏散距离过长，防火分区面积超规等技术难题奠定了基础；为此类建筑疏散设计与评估提供了必要的第一手基础数据，杜绝了由疏散速度的基础数据和预测模型“张冠李戴”带来的疏散安全风险和隐患；同时丰富和完善了我国现有的人员疏散理论体系，适应了我国城市化进程新趋势的需要。