Overview of Performance Based Practical Design

State transportation agencies (STAs) have increasingly turned to practical design and performance based practical design (PBPD) to inform project development and implementation — and to reduce project costs while optimizing systemwide benefits. PBPD is a design-up philosophy that encourages agencies to formulate projects to meet the purpose and need rather than adhering to ostensibly immutable design standards. This paper reviews practical design and PBPD concepts and initiatives and their application in a variety of contexts. It also summarizes best practices STAs can use to develop a PBPD program. As a holistic approach to project design, PBPD underscores context sensitive solutions that balance the needs of all roadway users, including motorists, bicyclists, and pedestrians. Common PBPD solutions include opting for low-cost enhancements, such as striping, signing, and rumble strips, as opposed to realignment; narrowing shoulder widths; redesigning projects to lower right-of-way costs; modifying interchange designs; and using design exceptions to build projects that fulfill project objectives. STAs committed to establishing robust PBPD programs will typically require 18 to 24 months to get a program off the ground. For an initiative to succeed, it is critical for executive leadership in an agency to advocate for PBPD; that agency staff learn about practical design and ongoing PBPD programs in other states; that a baseline performance evaluation of the tools, concepts, and resources currently used for project development be conducted; and that changes made to the project development process are thoroughly documented. The report closes with a series of recommended performance metrics the Kentucky Transportation Cabinet should consider adopting to improve its monitoring of critical bridge and roadway assets

Improved Bridge Joint Materials and Design Details

Expansion joints accommodate bridge movements that result from factors such as thermal expansion and contraction, concrete shrinkage, creep effects, live loading, settlement of the foundation and substructure, and environmental stressors. Expansion joints fall into two categories — open joints and closed joints. Open joints contain gaps that facilitate the passage of water and debris runoff through bridge joints. Flexible or stiff troughs are generally installed beneath open joints to direct runoff away from bridge elements. Closed joints produce a watertight seal that inhibits water, debris, and deicing materials from passing through bridge joints and remaining in contact with underlying bridge components. This study investigated materials and design strategies to improve the performance of both open and closed joints. Wanting to improve the durability of compression and strip seals, which degrade over time or become detached from bridge decks, Kentucky Transportation Center (KTC) researchers approached several seal manufacturers about developing new seals reinforced with puncture-resistant fibers such as Aramid. Ultimately, researchers were unable to reach an agreement with any manufacturer, as it appears they have little interest in developing better-performing conventional joint types, preferring instead to focus on producing new proprietary joint types. As the Kentucky Transportation Cabinet (KYTC) increases its use of proprietary joints, it should implement a rigorous monitoring program to track their performance. With respect to open joints, KTC investigated the use of self-purging troughs. First implemented by the Kansas Department of Transportation, they leverage the power of air flow and vibrations produced by traffic to improve the routing of water and debris through troughs and away from underlying bridge elements. Conventional troughs receive infrequent maintenance and can become clogged with debris. Self-purging troughs eliminate this problem, which can potentially help extend the service lives of bridges on which they are installed. KYTC will benefit from experimenting more widely with self-purging troughs

Synthesis of Kentucky’s Traveler Information Systems

After the United States Department of Transportation (USDOT) petitioned the Federal Communications Commission (FCC) to establish a dedicated phone number for real-time travel information services, the abbreviated 511 dialing code was founded in July 2000. The FCC reasoned that 511 services could reduce traffic congestion, air pollution, and the inefficient use of fossil fuels. 511 would, in turn, improve traveler safety. In 2010, the Federal Highway Administration (FHWA) mandated a set of requirements for systems that deliver real-time traffic information to the public. States DOTs were asked to comply with this mandate by November 2014. Many states, in addition to maintaining websites, also have dedicated mobile apps and a social media presence (e.g., one or multiple Twitter accounts) that communicate data on traffic and road conditions. Analysis of 511 usage data indicated that the number of phone calls received has dropped sharply since the mid-2000s. Conversely, the amount of traffic handled by KYTC’s websites and mobile apps has increased. Like the phone system, websites and mobile apps garner the most traffic during the winter months. Discussions with KYTC 511 stakeholders revealed that phone system will be less relevant — although necessary to maintain, particularly in rural areas. There was significant consensus among KYTC stakeholders about the strengths of the state’s current approach to delivering traffic information, and a number of improvements were put forward to enhance it in the future. A survey of Kentucky drivers revealed that a majority get their traffic information through digital content providers. Services such as Google and Waze are popular for retrieving maps and driving directions, while television and radio play an important role still, especially for the provision of information during hazardous weather. Government-provided services (i.e., 511, TRIMARC) are less popular among drivers, and only garner a fraction of the traffic of online services and traditional media. Discussions with other state DOTs revealed that many other states are currently in the process of rethinking their 511 and traveler information systems. Many plan to retool these over the next 2–3 years. While there was agreement among state DOTs that they will continue to provide authoritative traveler information, how they carry out this mandate is somewhat unclear

Jurisdictional Roadside Ditches

Section 404 of the Clean Water Act (CWA) mandates that state agencies and other entities perform compensatory mitigation when their activities impair jurisdictional waters. In the Commonwealth of Kentucky, the Kentucky Transportation Cabinet (KYTC) is required to pay in-lieu fees or purchase stream mitigation credits when a roadside ditch is impaired or relocated as part of a road construction project. In-lieu fees and stream mitigation credits are costly, and ditches that have suffered degraded habitat and loss of hydrogeomorphic functionality are treated as total losses when they are impacted by construction and maintenance activities. This raises the question of whether the United States Corps of Engineers (USACE) would be receptive to alternative mitigation and monitoring practices that impose a less stringent financial burden on the Kentucky Transportation Cabinet, but which still comply with CWA regulations. This report discusses methodologies used to evaluate the quality of instream and riparian habitat, Section 404 of the CWA and its implications for mitigation of lost or damaged jurisdictional ditches, and the strategies that have been used by other states to fulfill their Section 404 mitigation requirements. We highlight mitigation practices that depart from the norm and which place a less onerous financial burden on state transportation agencies. KYTC officials presented this report’s key findings to the USACE Louisville District Office in January 2015 in an effort to receive approval to experiment with novel restoration techniques. The USACE granted KYTC license to implement these techniques on a project-by- project basis. Before implementation on each project, the Cabinet must receive formal approval from USACE officials. Although this was not the blanket mandate that KYTC hoped for, it indicated the Louisville District is willing to study the effectiveness of alternative mitigation strategies. Despite the Cabinet’s request, USACE officials did not approve a plan to reduce post-restoration monitoring requirements. KTC researchers suggested that KYTC perform exhaustive monitoring of the performance of completed project that used alternative mitigation techniques. Having information on the short-, medium-, and long-term performance of these sites could–if the results are promising-pave the way to the wider adoption of alternative mitigation practices and could eventually reduce the level of post-restoration monitoring required by the USACE

Review of State Transportation Funding Initiatives

Despite significant cutbacks to the funding allocated to state departments of transportation (DOTs), demand for accessible and reliable transportation has increased even as existing transportation infrastructure has continued to age. Falling gasoline tax revenues resulting from increasing fuel efficiency and technological advancements have prevented state DOTs, including the Kentucky Transportation Cabinet (KYTC), from funding and financing much-needed transportation projects. Meanwhile, the Federal Highway Trust Fund, which provides funding to states and is tied to the federal gas tax, routinely receives cash infusions from the Federal General Fund to remain solvent—the federal gas tax has not been increased since 1993. Needing to invest in urgent transportation projects while facing stagnant revenue streams has led many state DOTs and researchers to begin exploring alternative funding sources as well as strategies to modify current revenue sources (e.g., gasoline tax, registration and licensing fees) to improve their sustainability. Ensuring the public understands that adequate funding is required to meet our infrastructure needs is critical as well—especially when transitioning to alternative funding mechanisms

Long-Term Corrosion Protection of Bridge Elements Reinforcing Materials in Concrete

Preventing or mitigating the corrosion of reinforcing steel in bridge decks is a major challenge for state transportation agencies. With agency budgets stretched thinner every year, they must implement strategies to extend the service lives of bridges and other critical structures. As such, it is imperative for them to adopt cost effective materials and maintenance practices to delay the onset of bridge corrosion. To assist the Kentucky Transportation Cabinet (KYTC) in its efforts to improve the condition of its bridges as well as its construction and maintenance practices, researchers at the Kentucky Transportation Center (KTC) investigated the use and performance of different reinforcing materials, supplementary cementitious materials, and concrete sealers. This document extensively reviews field and laboratory studies of these materials and draws general conclusions about their effectiveness. A survey administered to transportation agencies around the United States revealed that corrosion prevention and mitigation practices vary widely, but that the use of multiple corrosion-inhibition systems is growing. Based on our literature review and analysis of practices used by other state transportation agencies, we recommend the use of multiple corrosion inhibition methods to defend against bridge corrosion. For the construction of new reinforced concrete structures, a multiple approach to corrosion resistance could prove highly beneficial and offer a cost-effective strategy to prolong the service lives of bridges. Recommended actions are proposed for KYTC, which are geared toward strengthening its bridge construction and maintenance program

Green Infrastructure

The transportation industry has increasingly recognized the vital role sustainability serves in promoting and protecting the transportation infrastructure of the nation. Many state Departments of Transportation have correspondingly increased efforts to incorporate concepts of sustainability into the planning, design, and construction phases of projects and congruently adopted sustainability measures into their internal standard policies and procedures. Sustainably constructed highways foster economic development, promote stewardship of the environment, and solicit citizen involvement for an integrated, comprehensive approach to project planning. As part of an effort to understand the extent to which sustainable design and construction principles are being used, this report selects and analyzes three case studies involving previously completed KYTC projects and assesses their commitment to sustainable concepts. Specifically, this report examines the extent to which KYTC utilized sustainable concepts for each case study as described in FHWA’s INVEST rating system. This research effort comprised three components. First, KTC researchers analyzed KYTC’s policies and manuals for project planning, design, and construction and determined the extent to which INVEST criteria and related principles were incorporated into their standard processes. Second, KTC analyzed the individual case studies themselves, to include project plans and other relevant documentation. Finally, KTC conducted interviews with each of the KYTC district offices responsible for managing those previously completed projects and obtained feedback on the INVEST criteria used for each particular project. Following this approach, KTC validated and finalized the assigned scoring ratings for each case study in accordance with the INVEST scoring guidance. In summary, this report describes the sustainable concepts and corresponding INVEST scores for each project, presents a summary of the main findings, and provides recommendations for the way ahead

Inland Waterways Funding Mechanisms Synthesis

The inland waterway system is a vital part of the nation’s multi-modal freight network. Although less visible than other modes, inland waterways allow shippers to transport bulk commodities in a relatively cheap and environmentally-friendly method. To ensure this transportation mode remains a feasible option and accommodates growth, it must continue to be safe, efficient, and functional. This synthesis provides comprehensive perspective on the financial prospects of the inland waterways system. It analyzes current funding levels, along with proposed funding changes and reforms. Financial support for the inland waterways system comes from the Inland Waterways Trust Fund (IWTF). Historical data gathered provides evidence that the IWTF resources have rapidly declined in recent years, limiting the number of infrastructure projects that can be undertaken. Some of this is can be attributed to the lack of a fuel tax increase since 1995. The fuel tax serves as the primary revenue source for the IWTF. The purchasing power of each dollar is therefore eroded due to the increase of construction costs, coupled with the tax revenue not increasing.In order to reinforce the IWTF and deal with a mounting project backlog, several funding reforms have been proposed in addition to changes in project delivery and prioritization. Many reforms include raising the fuel tax and changing the current cost share structure. Other proposals lay out different options, such as tolling locks and dams or instituting license fees.In order to reverse the decline of the IWTF, it appears that substantive changes may be required. The past and current state of the system also provides insight as to how previous investment levels have impacted reliability.Measures of lock performance, such as the number of outages (both scheduled and unscheduled) and the duration of lock outages, are used to assess system dependability. These reveal that in recent years there has been an increase in outages and outage durations. Possible factors include a reduction in funding for construction and maintenance projects, which compounds the increasing infrastructure age issue.Unexpected closures impact shippers by causing unplanned delays. These delays increase costs of inland waterway shipments by idling freight and reducing reliability.In turn, reduced system reliability may prompt modal shifts as freight shippers seek more consistent modes of transport. This synthesis provides valuable information for stakeholders and policymakers regarding current funding levels and investments in the inland waterway system.The initial evidence in this report shows that declining funding levels, coupled with aging locks and dams, are likely contributing to increases in lock outages.If such issues are to be rectified, the reforms detailed here provide a starting point for changing the current funding regime

KYTC Maintenance Field Operations Guide Supplement

The Kentucky Transportation Cabinet (KYTC) is tasked with managing an asset portfolio that includes over 27,500 miles of roadway and 9,000 bridges. Keeping these assets in sound condition demands significant effort from KYTC’s Division of Maintenance, which includes activities ranging from mowing and litter pickup to cleaning out culverts and performing emergency roadway work. Despite the immense responsibilities shouldered by Maintenance personnel, until this project the Cabinet’s 12 districts lacked a systematic method for capturing and recording maintenance activities. Through a series of workshops held in each KYTC’s district with Section Engineer and Maintenance Supervisors, researchers at the Kentucky Transportation Center (KTC) facilitated efforts to inventory routine maintenance activities, document how frequently each activity is done, and capture the ways in which maintenance functions are adjusted in response to special projects (which generally receive priority over general maintenance functions). Key products of this research include a Statewide Maintenance Calendar, which defines — based on a combination of stakeholder feedback and statistical analysis — optimal time intervals for undertaking key maintenance activities, as well as district-specific maintenance calendars. Having recourse to these calendars will help district staff more efficiently plan, schedule, and coordinate maintenance functions

Inland Waterway Operational Model & Simulation Along the Ohio River

The inland waterway system of the U.S. is a vital network for transporting key goods and commodities from the point of production to manufacturers and consumers. Shipping materials via the inland waterways is arguably the most economical and environmentally friendly option (compared to hauling freight by trains or railways). Despite the advantages the inland waterways enjoys over competing modes, key infrastructure – such as locks and dams, which help to control water levels on a number of rivers and make navigation possible – is declining. Limited funds have been allocated to make the necessary repairs to lock and dam facilities. Over the past 10 years Inland Waterways Trust Fund resources (which historically funded maintenance and improvement projects) has steadily declined. Locks and dams are of particular importance, because they assist in the maintenance of navigable depths on many of the major inland waterways (Ohio River, Upper Mississippi River, Tennessee River). To better understand the operation of the inland waterway system, this report examines a portion of the Ohio River (extending from Markland Locks and Dam to Lock 53). The specific focus is to determine what delays barge tows as they attempt to lock through these critical facilities. The Ohio River is a particularly important study area. In many ways it is representative of the conditions present throughout the inland waterways system. The average age of the lock and dam facilities exceed 50 years along our study segment. Most of these facilities are operating beyond their intended design life. As locks age, they increasingly demand more scheduled and unscheduled maintenance activities. Maintenance activities often require temporarily shuttering a lock chamber and diverting traffic through another onsite chamber (often of smaller capacity). All of the facilities included in the research area have two lock chambers ‐ thus, if one goes down for maintenance all vessels are diverted through the second chamber. In many cases this situation can produce extensive delays, which precludes cargo from reaching the destination in a timely manner. Recently, the aggregate number of hours that shippers and carriers lose due to delays has escalated. Although the U.S. Army Corps of Engineers – the agency responsible for the management and oversight of locks and dams – has worked to keep traffic flowing on the river, tightening budgets hamper efforts. For shippers and carriers to make informed decisions about when and where to deploy freight on the river, they require knowledge that illuminates factors that are most significant in affecting transit times. In particular this applies to certain conditions that are likely to create delays at lock and dam facilities. The purpose of this report is to 1) develop a comprehensive profile of the Ohio River that provides an overview of how it is integral to U.S. economic security 2) identify salient river characteristics or externally‐driven variables that influence the amount of water flowing through the main channel which consequently impacts vessels’ capacity to navigate 3) use this information (along with a 10‐year data set encompassing over 600,000 observations) to develop an Inland Waterways Operational Model (IWOM). The IWOM objective is to provide the U.S. Army Corps of Engineers, shippers, carriers, and other interested parties with access to8 a robust method that aids in the prediction of where and when conditions will arise on the river that have the potential to significantly impact lockage times and queue times (i.e. how long a vessel has to wait after it arrives at a facility to lock through). After qualitatively reviewing different features of the river system that affect vessel traffic, this report outlines two approaches to modeling inland waterway system behavior – a discrete event simulation (DES) model which uses proprietary software, and the IWOM. Although the DES produced robust findings that aligned with the historical data (because it relies upon proprietary software), it does not offer an ideal platform to distribute knowledge to stakeholders. Indeed, this is the major drawback of the DES given a critical objective of this project is to generate usable information for key stakeholders who are involved with inland waterway operations. Conversely, the IWOM is a preferable option given it relies on statistical analysis – in this sense, it is more of an open‐source solution. The IWOM uses linear regression to determine key variables affecting variation in lockage time. The final model accounts for over two‐thirds of the observed variation in lockage times from 2002‐2012, which is our study period. Practically, this means that the difference between predicted values and observed delay times is significantly less than how the delays vary around the composite average seen in the river system (R2 = 0.69). The IWOM confirms that variations in river conditions significantly affect vessel travel times. For example, river discharge ‐ the direction a vessel moves up or down a river ‐ meaningfully influences lockage times. The freight amount a vessel carries, which is represented by the amount of draft and newness of a vessel, influences lockage times. Larger vessels with more draft tend to wait longer and take longer to complete their lockage. The IWOM is less successful at predicting delay times. Because there is greater instability in this data only a modest amount of variation is explained by the model (R2 = 0.23). This, in turn, partly reflects in spillover from one vessel to the next that is difficult for the simulation to impose and account for therefore requiring additional logic. Once completed, the IWOM was used to parameterize a simulation model. This provided a graphical representation of vessels moving along the river. Users have the capability of adjusting the effects of different variables to anticipate how the system may react, and what changes in vessel traffic patterns emerge. This information will be of great use for stakeholders wanting to gain a better understanding of what conditions lockage times will increase or decrease, why delays emerge, and consequently how these impact traffic flows on the river. In programming a simulation model, users are able to visualize and intuit what causes vessel travel times to vary. Although the regression model accomplishes this, for many users this would prove unwieldy and difficult to grasp beyond a conceptual, abstract level. Matching up regression results with a visual counterpart lets users gain immediate and intimate knowledge of river and vessel behavior – this in turn can positively affect shipper and carrier modal choices. The report concludes with some recommendations for IWOM implementation and thoughts on future research needs. Also discussed are the implications results from the present study have for improving our ability to safely, securely, and swiftly move freight on the inland waterways network