AI 中文总结
研究无出口人群中机械危险，通过弹性重定向模型和社会力模型及其耦合动力学，用社会群体凝聚力等量化风险，揭示耦合动力学产生的壁面压力/接触载荷权衡及相边界，为高密度场所人群风险缓解和安全规划提供指导。
AI 中文摘要
在封闭场所的人群安全通常通过疏散性能或碰撞前避免来评估，而在无出口的密集集会中的直接机械危险仍知之甚少。我们研究了弹性重定向模型（ERM）、社会力模型（SFM）及其耦合动力学。碰撞后行为由社会群体凝聚力（$\gamma_g$）和壁面缓冲（$\gamma_w$）表示，风险由宏观壁线压力（$P_{\text{wall}}$）和微观最大单主体碰撞冲量（$\delta p_{\text{max}}$）量化。在ERM中，凝聚力和壁面缓冲通常通过将主体保留在主体中来降低$P_{\text{wall}}$，但大群体在中等凝聚力下表现出高$\delta p_{\text{max}}$危险窗口。随着$\gamma_g\rightarrow1$，局部配对抑制簇生长并将动能从相对质心运动转移，降低$\delta p_{\text{max}}$。SFM推动和滑动放大$\delta p_{\text{max}}$，特别是当主体-主体和主体-壁相互作用共存时，而主动驱动通过近壁积累提高$P_{\text{wall}}$。耦合动力学产生壁面压力/接触载荷（$P$-$p$）权衡。有限尺寸缩放揭示了在$\gamma_w=0.5$处由独立主体引起的相边界，其特征是磁化率不连续，以及沿着$(1-\gamma_w)(1-\gamma_g)=0.5$的有限段由成组主体引起的连续相边界，其特征是磁化率发散并在临界点终止。两者在无社会力的ERM中都消失，表明它们源于耦合的ERM+SFM动力学。这些结果为无出口高密度场所的人群风险缓解和安全规划提供了机制指导。
英文摘要
Crowd safety in confined venues is usually evaluated through evacuation performance or pre-collision avoidance, while direct mechanical hazards in dense gatherings without egress remain poorly understood. We study an Elastic Reorientation Model (ERM), a Social Force Model (SFM), and their coupled dynamics. Post-collision behavior is represented by social-group cohesion ($γ_g$) and wall buffering ($γ_w$), while risk is quantified by the macroscopic wall line pressure ($P_{\text{wall}}$) and the microscopic maximum per-agent collision impulse ($δp_{\text{max}}$). In the ERM, cohesion and wall buffering generally reduce $P_{\text{wall}}$ by retaining agents in the bulk, but large groups exhibit a high-$δp_{\text{max}}$ hazard window at intermediate cohesion. As $γ_g\rightarrow1$, local pairing suppresses cluster growth and shifts kinetic energy from relative to center-of-mass motion, reducing $δp_{\text{max}}$. SFM pushing and sliding amplify $δp_{\text{max}}$, especially when agent-agent and agent-wall interactions coexist, while active driving raises $P_{\text{wall}}$ through near-wall accumulation. The coupled dynamics produces a wall-pressure/contact-load ($P$-$p$) trade-off. Finite-size scaling reveals an independent-agent-induced phase boundary at $γ_w=0.5$, characterized by a susceptibility discontinuity, and a grouped-agent-induced continuous phase boundary along a finite segment of $(1-γ_w)(1-γ_g)=0.5$, characterized by divergent susceptibility and terminating at a critical point. Both disappear in the social-force-free ERM, showing that they emerge from the coupled ERM+SFM dynamics. These results provide mechanistic guidance for crowd-risk mitigation and safety planning in high-density venues without egress.
Comments16 pages, 8 figures
