Date of Award:


Document Type:


Degree Name:

Doctor of Philosophy (PhD)


Civil and Environmental Engineering

Committee Chair(s)

Anthony Chen


Anthony Chen


Ziqi Song


Gilberto E. Urroz


Keith M. Christensen


Yong Seog Kim


The objective of this dissertation was to study walking behaviors of pedestrian groups involving individuals with disabilities. To this end, large scale controlled walking experiments were conducted at Utah State University (USU) to examine walking behaviors in various walking facility types, such as passageway, right angle, oblique angle, queuing area, bottleneck, and stairs. Walking experiments were conducted over four days involving participants with and without disabilities. Automated video identification and semi-structured questionnaires were used to collect revealed and stated walking data. This study provided statistical analysis and models to study three different aspects of operational walking behaviors.

Firstly, walking speed was examined as one of the most important behavioral variables. The differences in crowd walking speeds were carefully noted in analyzing the effects of adding individuals with disabilities and the impacts of different indoor walking facilities. Results showed that the presence of individuals with disabilities in a crowd significantly reduces the overall crowd speed. Statistical analysis also provided to compare walking speeds of pedestrian groups involving individuals with disabilities in different walking environments.

Secondly, the dissertation proposed a framework to study the interactions of different pedestrian groups. Specifically, a mixed time headway distribution model was used to examine the time headway between followers and different leader types. In addition, the implications of interaction behaviors were studied based on the capacity of the queuing area behind the doorway. Results revealed that: (1) individuals with disabilities had significant effects on capacity reduction; (2) individuals with visual impairments and non-motorized ambulatory devices had the minimum capacity reduction effects in queuing area; and (2) individuals with motorized wheelchairs and individuals with mobility canes had the maximum capacity reduction effects in queuing area.

Lastly, this study explored how a heterogeneous mix of pedestrians (including individuals with disabilities) perceive and evaluate operational performance of walking facilities. Both trajectory and survey data sources were used, and an ordered statistical approach was applied to analyze pedestrian perceptions. Results indicated that individuals with disabilities were less tolerant of extreme congested environments. Furthermore, analysis showed that the Level of Service (LOS) criteria provided in HCM does not follow the actual perceptions.