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Bike-lane Traffic Impact Assessment Activity for High School Students ( Work in Progress )
| Content Provider | Semantic Scholar |
|---|---|
| Author | Kianfar, Jalil |
| Copyright Year | 2017 |
| Abstract | High school students use the surface transportation system virtually every day and can relate to traffic congestion, travel delays, and roadway safety. Moreover, trends observed in the Federal Highway Administration driver’s license data and in the National Household Travel Survey data suggest that the popularity of active modes of transportation, such as cycling, is continuously increasing among the high school age group. In this paper, an activity is proposed to show how mathematical models can be used to assess the impact on traffic congestion of retrofitting a roadway with bike lanes. This paper builds upon the familiarity of students with the transportation system and pursues three objectives. First, students learn how math and physics principles can be used to model complex systems, such as a surface transportation system. Second, students are introduced to the decision-making process and before-and-after studies in which quantitative measures are used to support a decision. Third, students learn how engineers can potentially influence city planning and affect communities. In the first steps, students learn how math can be used to model driver behavior and to develop car-following models. Then, students use traffic simulation software to model the flow on an urban corridor. The software considers traffic volume, speed limits, traffic signal timing, and the number of travel lanes to estimate performance measures such as the length of queues, travel delays, and CO2 emissions. In the next step, students modify the simulation model and remove a travel lane to provide the space necessary for a bike lane and a buffer lane. Students discuss the traffic simulation model’s outputs and make a recommendation about whether to install a bike lane on the roadway. VISSIM traffic simulation software, a commercial software often used by engineering firms and public agencies to model transportation networks, was used in this activity. A classroom license for the software is available to educators at no charge. Twenty high school students in grades 9 through 12 participated during a one-week engineering summer camp at Saint Louis University. The activity was completed in two hours. Students worked in pairs, with one faculty member and two counselors facilitating the discussion and hands-on computer simulation. As a work in progress, this paper presents the author’s primary observations about students’ learning and discusses future directions for this research. Introduction and Review of Literature Restoring and improving urban infrastructure is identified by the National Academy of Engineering (NAE) as one of the grand challenges of engineering in the 21st century. One of the objectives in meeting this challenge is to integrate sustainable modes of transportation, such as walking, biking, and public transit, into the urban transportation system. This activity demonstrates a process used by transportation engineers to study the feasibility of retrofitting an urban street with a bike lane. The activity proposed in this paper is different from existing transportation-related outreach in three main ways: 1) The traffic simulation model can be customized to study a local street that is familiar to high school students participating in the activity. 2) The learning outcomes extend beyond data-driven decision making. The activity highlights the role of engineers in shaping communities and the importance of public engagement. 3) The activity provides a glimpse of a fully automated driving environment to students. A review of the literature shows several activities that have been developed by educators to introduce middle and high school students to the transportation engineering profession. Luken and Mumbower (2010) proposed three such activities. The first investigated the tradeoff between various modes of transportation. The second aimed at informing students about design objectives in transportation projects. The third focused on users of transportation systems and the role of engineers in accommodating their needs. In the third activity, students were tasked with planning the daily activities of a household of two parents and two children. Elam et al. (2011) developed a web-based tool to introduce students to transportation history, road signs and pavement markings, traffic signal timing, crash reporting, hurricane evacuation, and alternative modes of transportation. The tool was designed to be part of high school transportation curricula. Islam and Brown (2013) developed a board game with rules similar to Monopoly. Each player takes the role of a transportation engineer and has to address the transportation needs of the city with the resources allocated to them. Shekhar et al. (2014) developed a “Cloud-based, Collaborative, Scaled-up Modeling Environment (CSuMo)” for traffic simulation. The tool was built using the Google Earth application programming interface (API), and implemented the Simulation of Urban Mobility (SUMO) as the computational engine. Activities were developed to study the impact of changes in signal timing plans and volume of passenger cars and trucks on travel delay and the length of the queue at an intersection. Bike-lane Traffic Impact Assessment Activity This section provides an overview of the bike lane impact assessment activity modules used in this study. Introduction to Transportation Modeling: The activity starts with brainstorming solutions for improving the flow of vehicles at a busy intersection. The instructor facilitates the discussion to arrive at solutions such as modifying the intersection in one of several ways: two-way stop, allway stop, signal-controlled, roundabout, or interchange. In the next step, the instructor raises the question of methods for assessing the effectiveness of those alternatives. Potential answers from students include building a physical model, observing similar intersections in the city, and modeling the design scenarios on a computer. The students and instructor then discuss the practicality, accuracy, and cost of each evaluation method. Computer simulation is the most accurate and practical method for evaluating design alternatives, and could cost less than other three methods. The students are then asked to suggest the road characteristics and designscenario aspects that should be incorporated into a traffic-simulation model. Volume and percentage of heavy vehicles, number of lanes, lane width, speed limit, and signal timing are among the factors that should be considered. The other key question is how to replicate behavior of drivers in a computer. Car following models: These models explain how cars follow each other on the road. A computer traffic simulation program implements these models to replicate drivers’ behavior. Equation 1 shows a car following model developed by General Motors researchers in the 1950s. ?̇?xff(tt + ∆tt) = αα[?̈?xff(tt) − ?̈?xll(tt)] (Equation 1) where ?̈?xff(tt) and ?̈?xll(t) are the acceleration rate of a following vehicle and a lead vehicle, respectively, at time t. The expression ?̇?xff(tt + ∆tt) is the speed of a following vehicle at time ∆tt after tt. The term αα is a constant value. These car following models, combined with physics kinematics equations, can be used to calculate the location and trajectory of vehicles. Students use these models to calculate the movement of two vehicles over a 5-second period. It is assumed that ∆tt is 1 second. The instructor emphasizes that animations and transportation measures of effectiveness obtained from traffic simulation models are developed according to car following models. Transportation measures of effectiveness (MOEs): In the next step, the instructor and students discuss indexes that could be used to quantify the quality of travel experienced by road users. Students are asked to reflect on their personal daily travel experiences and mention when they think the transportation system is or is not working well for them. Through guided discussions, students typically list indexes such as travel delay, length of vehicle queues at intersections, and number of vehicle stops before traveling through an intersection as MOEs of the transportation system. The instructor can allude to environmental MOEs such as fuel consumption, fuel cost, and emissions from vehicles and their impact on users and nonusers of the road. Studying Traffic Impacts of a Bike Lane: In the next step, the instructor facilitates a conversation about active modes of transportation, such as cycling and walking, and discusses their health benefits and impacts on the environment. The discussion then transitions into the NAE grand challenge and the need for restoring and improving urban infrastructure. It highlights that urban streets were historically designed to move vehicles faster and that other modes of transportation were not necessarily considered in the designs. The instructor then refers to Grand Boulevard, a street next to the summer camp site. There are three lanes on the northbound Grand Boulevard (Figure 1-a). The far right lane is an 8-foot-wide dedicated right-turn-only lane and appears underutilized (Figure 1-b). It appears that this lane could be retrofitted as a bike lane. Students are asked to propose a method for analyzing the impact of such a change. They are guided to determine MOEs for the decision-making process and to identify the data needed to develop a simulation model of the street. Figure 1: a) street view of northbound Grand Boulevard b) AM peak-hour traffic volume (vehicle/hour) at Grand BLVD and Lindell BLVD intersection The instructor elaborates on the data-driven decision-making process in roadway engineering projects. The existing roadway conditions, commonly referred to as a no-build scenario, are studied first, and MOEs for no-build scenarios are determined. In the next step, the design alternatives are modeled, and MOEs for scenarios are determined. The instructor then outlines the propos |
| File Format | PDF HTM / HTML |
| Alternate Webpage(s) | https://peer.asee.org/board-99-bike-lane-traffic-impact-assessment-activity-for-high-school-students-work-in-progress.pdf |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
