Qiling Zou

Bio: Qiling Zou is an academic researcher from Colorado State University. The author has contributed to research in topics: Resilience (network) & Flow network. The author has an hindex of 6, co-authored 9 publications receiving 148 citations. Previous affiliations of Qiling Zou include Hunan University.

State-of-the-Art Review of Dynamic Impact Factors of Highway Bridges

Abstract: Dynamic impact of moving vehicles on bridges is an important and long-standing issue in the design and evaluation of bridges and has received much attention from researchers and engineers The use of the dynamic impact factor (IM) to account for the impact effect of vehicles has been widely accepted in bridge engineering Accurate evaluation of the IM will lead to safe and economical designs of new bridges and provide valuable information for condition assessment and management of existing bridges Nevertheless, agreement on the evaluation of IMs is yet to be reached Numerous studies have shown that the evaluation of the IM is a difficult task because it is influenced by a large number of parameters and uncertainties As a result, different forms and values of IMs are specified by different bridge design codes and this disagreement has been debated in many studies in the past few decades Furthermore, some field tests observed that the IMs in design codes are overestimated while many other field

Comparative Study of Different Numerical Models for Vehicle–Bridge Interaction Analysis

Abstract: In this paper, a comprehensive comparative study on several existing vehicle–bridge interaction (VBI) models is presented with the aim to provide a useful reference to the selection of vehicle and bridge models when conducting the VBI simulation. A simply-supported slab-on-girder highway bridge and the AASHTO HS20-44 vehicle are adopted in the numerical analysis. The bridge is modeled as an Euler–Bernoulli beam, grillage, plate-and-beam system and solid-element system, respectively, while the vehicle is modeled as a moving-force, moving-mass and spring-damper-mass (SDM) system, respectively. Other factors, including the road roughness and the contact condition between the vehicle tire and bridge, are also considered. The effects of different VBI models on the bridge responses are studied and the results from different models are compared in terms of their accuracy, efficiency and suitability. The results show that the accuracy of different types of bridge responses calculated varies with the number of bridge vibration modes used in the simulation. It is also found that the type of element used in the bridge model and the vehicle tire model both have a larger impact on the bridge acceleration than bridge deflection.

Resilience Modeling of Interdependent Traffic-Electric Power System Subject to Hurricanes

Abstract: Highly interconnected critical infrastructure systems (CISs) are the backbone of the well-being of the modern societies. It is crucial to account for the interdependencies among CISs in ass...

Effects of Autonomous Vehicle Ownership on Trip, Mode, and Route Choice

Abstract: Autonomous vehicles (AVs) may significantly change traveler behavior and network congestion. Empty repositioning trips allow travelers to avoid parking fees or share the vehicle with other household members. Computer precision and reaction times may also increase road and intersection capacities. AVs are currently being test driven on public roads and may be publicly available within the next two decades; they therefore may be within the span of 20- to 30-year planning analyses. Despite this time scale, AV behavior has yet to be incorporated into planning models. This paper presents a multiclass, four-step model that includes AV repositioning to avoid parking fees (although incurring additional fuel costs) and increases in link capacity as a function of the proportion of AVs on the link. Demand is divided into classes by value of time and AV ownership. Mode choice—parking, repositioning, or transit—is determined through a nested logit model. Traffic assignment is based on a generalized cost function of ti...

Extracting bridge frequencies from the dynamic response of a passing vehicle

Abstract: The frequencies of vibration of bridges represent a kind of information that is most useful for many purposes. Traditional vibration tests aimed at measuring the bridge frequencies often require on-site installation of the measurement equipment, which is not only costly, but also inconvenient. As a first attempt, the idea of using a vehicle moving over a bridge as a message carrier of the dynamic properties of the bridge is theoretically explored in this paper. In order to identify the key parameters dominating the vehicle–bridge interaction response, while illustrating the key phenomena involved, assumptions that lead to closed-form solutions are adopted in the analytical study. For instance, a vehicle is modelled as a sprung mass, and a bridge as a simply supported beam considering only the first mode of vibration. The concept of extracting bridge frequencies from a passing vehicle, however, is not restricted by the aforementioned assumptions, as will be demonstrated in an independent finite element study, which do not rely on any particular assumptions. Concluding remarks are given concerning the feasibility of extracting the bridge frequencies from the dynamic response of a passing vehicle, along with directions for future research identified.

Cascading Failures in Internet of Things: Review and Perspectives on Reliability and Resilience

Abstract: In the Internet of Things (IoT), various devices operate collaboratively in collecting data, relaying information to one another, and processing information intelligently. Due to interactions and dependencies between the IoT devices, the malfunction of one device may trigger a cascade of unexpected and often undesired state changes of other devices, introducing or accelerating catastrophic cascading failures. Understanding the causes of cascading failures and modeling their behavior and effects is crucial for guaranteeing the reliability of IoT systems and delivering the desired quality of service. This article systematically reviews cascading failures modeling and reliability analysis methodologies, as well as mitigation strategies for building the resilience of IoT systems against cascading failures. The review covers diverse IoT applications, from smart grids to smart homes, from sensor networks to IoT cloud computing, and from transportation networks to interdependent infrastructure networks. Opportunities and open research issues are also discussed in relation to restrictions of the current cascading failure models and methods, and potential new technologies and complexity of the constantly evolving IoT systems.