## 1 Introduction  
As construction projects continue to increase in densely populated urban areas, sidewalks adjacent to construction sites are often occupied by building materials and equipment [1, 2, 3]. Such occupation reduces the available pedestrian space, forcing pedestrians to navigate narrow or disrupted pathways and thereby compromising the overall quality of walking [4]. In severe cases, obstructed sidewalks compel pedestrians to detour onto vehicle roadways or other hazardous areas, increasing the risk of pedestrian accidents [5, 6]. Given that pedestrian injuries arising from falls, slips, and trips significantly outnumber the reported fatalities yet remain unrecorded in official accident statistics [7, 8, 9], ensuring pedestrian safety near construction sites is a critical issue. To guarantee safe walking conditions around construction sites, many regulations prohibit excessive encroachment that interferes with pedestrian flow unless an alternative pedestrian route is provided [10]. However, despite these clear guidelines, effective enforcement and implementation remain limited because construction sites are temporary and change rapidly [11, 12, 13]. Moreover, improper safety practices and insufficient attention to pedestrian safety exacerbate the challenges of conducting timely inspections and maintaining compliance [14, 15]. In response to these issues, various studies have proposed methods to evaluate side-walks in terms of pedestrian comfort and safety. For example, [PERSON] et al. [12] conducted field observations to identify the potential risk factors affecting pedestrian safety on a temporary sidewalk near a light rail transit construction project in Indonesia. Although such expert-led audits provide in-depth, professional assessments of on-site conditions, they can be costly and time-consuming. Consequently, researchers have increasingly explored image- or virtual reality-based survey approaches. [PERSON] et al. [16] asked pedestrians to rate their satisfaction and dissatisfaction by viewing real images of diverse walking environments. [PERSON] et al. [17] employed 360-degree panoramic street views enhanced with virtual reality technologies to identify scenes perceived as more pleasurable or safe for walking. As image-based survey methods have become more common, researchers have adopted subjective indicators to capture pedestrians' evaluations of their walking environments. One such indicator is perceived risk, which refers to an individual's assessment of the potential danger in a given setting. Although the perceived risk may not directly correspond to the actual risk, it plays a critical role in safety research, as behavior is often guided by subjective perceptions rather than objective conditions [18; 19]. For example, [PERSON] et al. [20] observed that pedestrians who recognize a heightened risk tend to walk in haste to avoid perceived hazards, which, paradoxically, increases the likelihood of engaging in risky behavior. Building on this perspective, other studies have highlighted that objective environmental attributes can shape pedestrians' perceived risk and, in turn, influence their walking behavior. For example, [PERSON] and [PERSON] [21] found that the presence of abandoned waste and piled-up construction materials on sidewalks heightens pedestrians' perceived risk, leading many to avoid walking altogether. Conversely, [PERSON] and [PERSON] [22] reported that physical buffers, such as barrier walls, can reduce pedestrians' perceived risk by providing a clear sense of separation and safety from nearby construction activity, thereby encouraging them to continue walking. Although macro-level studies can capture general urban features, merely noting the presence or absence of specific objects reveals little about how these factors affect pedestrians' perceived risk [23]. In this context, researchers have introduced more fine-grained, micro-level approaches that examine factors such as surface materials, slopes, and width [2; 11; 24; 25; 26; 27].