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Abstract XXIX

Measuring the Performance of Transit Relative to Livability

Measuring the Performance of Transit Relative to Livability

This project sought to understand the relationship between urban form, transit service characteristics, and ridership measured at the stop level. Most previous work in this area has looked at these issues separately, by either linking system performance (e.g. on-time performance, cost, etc.) to ridership or exploring the connection between urban form (e.g. density) and transit use. This project synthesized these disparate approaches. While transit service characteristics (e.g. frequency, travel time, etc.) are important to help individuals reach their desired destinations, most transit users are pedestrians at the beginning and end of any transit trip. Therefore, focusing on the walkable zone around each transit stop was also important. ​
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Characterizing Oregon's Supply Chains​

Characterizing Oregon's Supply Chains
 
In many regions throughout the world, freight models are used to aid infrastructure investment and
policy decisions. Since freight is such an integral part of efficient supply chains, more realistic
transportation models can be of greater assistance. Transportation models in general have been moving away from the traditional four-step model into activity-based and supply chain-based models. Personal transportation models take into consideration household demographics and why families travel.

Freight research has yet to fully identify the relationships between truck movements and company
characteristics, so most freight models use the methodology of personal transportation models, despite situational differences. In an effort to classify freight companies into groupings with differentiated travel movements, a survey of licensed motor carriers was designed and conducted in Oregon. The survey consisted of 33 questions. Respondents were asked about their vehicle fleets, locations served, times traveled, types of deliveries, and commodities. An analysis of the data revealed clusters of company types that can be distinguished by determining characteristics such as their role in a supply chain, facilities operated, commodity type, and vehicle types. An assessment of how the relationships found can be integrated into state models is also presented.​
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Developing an Oregon Access Management Best Practices Manual

Developing an Oregon Access Management Best Practices Manual
 
This Report reviews an Oregon research effort to develop an Oregon Access Management Best Practices Manual. In particular, this research effort develops a resource to help transportation professionals quantify safety and operational effects of various access management strategies, provide measurable criteria to evaluate these access management techniques, and identify data collection practices necessary to successfully perform these assessments. It is the expectation that this manual can be used by engineers, decision makers, and educators to help the transportation community better understand the appropriate application of access management strategies and how to quantify benefits of the various access management options.
 
This report includes a literature review of safety and operational benefits for a variety of access management configurations. Included in this benefits summary is information about perceived and measured economic impacts of access management even though they are not explicitly included in the companion manual. In addition, this report summarizes example data for access management through the use of case studies, and includes (in the appendix) a standalone proposed access management best practices manual. The case studies were used to test practicality of acquiring various data elements and are not directly reflected in the manual.

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VSL System for Wet and Extreme Weather Conditions

Evaluation of a Variable Speed Limit System for Wet and Extreme Weather Conditions​
Weather presents considerable challenges to the highway system, both in terms of safety and operations.  From a safety standpoint, weather (i.e. precipitation in the form of rain, snow or ice) reduces pavement friction, thus increasing the potential for crashes when vehicles are traveling too fast for the conditions.  Under these circumstances, the posted speed limit at a location may no longer be safe and appropriate.  From an operations standpoint, inclement weather could have considerable impacts on the capacity of the highway system and the efficiency of using the system by motorists.  Consequently, new approaches are necessary to influence motorists’ behavior in regards to speed selection when inclement weather presents the potential for reduced pavement friction at a given location.  Among these approaches is the use of Variable Speed Limit (VSL) systems.  This document presents the results of initial work completed in the development of such a system.  The work completed included a literature review related to different aspects and types of VSL systems, as well as a review of sensor systems capable of providing roadway grip/friction measurements.  The work also developed a Concept of Operations and Requirements for the prospective VSL system, with detailed information provided in the Appendix.  Sensor testing was completed on the Vaisala DSC 111 to determine its accuracy and applicability for inclusion in the prospective VSL.  Finally, a policy and legal implications review that was completed by Oregon Department of Transportation staff including a summary of Oregon’s recently enacted administrative rules on use of variable speed limits and statutes and rules adopted by other states is presented. ​
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Aluminum Sign Recycling

Aluminum Sign Recycling
 
The intent of this investigation was to determine whether aluminum signs that underwent the hydro-stripping process would meet ODOT’s specification for sign blanks based primarily on whether the anti-corrosive coating was removed during stripping process. Due to a change in the anti-corrosive coating applied to new sign blanks, which resulted in two types of coatings in ODOT’s sign inventory, the outcome of the investigation was a set of baseline measurements for the hydro-stripping process.
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Glass Fiber Reinforced Composite Bridge Decks

Strength and Fatigue of Three Glass Fiber Reinforced Composite Bridge Decks with Mechanical Deck to Stringer Connections
Replacement of the steel grating deck on the lift span of the Morrison Bridge in Portland, OR, will utilize glass fiber reinforced polymer (FRP) panels to address ongoing maintenance issues of the deteriorated existing deck, improve driver safety and introduce bridge water runoff treatment. This report outlines the testing methods and results of an experimental program aimed primarily at evaluating a new open cell deck. While most FRP panels are connected via shear studs that are grouted within isolated pockets, the panels in this case were bolted directly to the steel stringers. Two different FRP deck options were evaluated for comparison: one with open cells and the other with more conventional closed box extrusions. The objective was to evaluate the strength of the FRP to steel stringer connection with individual bolt connection tests, the strength and fatigue resistance of the FRP decks themselves, and the relative lateral stiffness contribution of the panels. Additional related tests were also included to complement the research effort such as the inclusion of tests on a closed box deck removed from the Broadway Bridge in Portland, OR, and strength tests of a retrofit attachment option of FRP deck to stringer using bolted clamps.

While the monotonic, flexural, and shear strength of the deck exceeded the design values, the associated failure mode of the open cell panels was consistently via shear flow through the stem near the top flange. The residual displacement of failed FRP decks was found to be minimal, which would make visual identification of failed panels without applied load difficult in the field. Fatigue strength evaluation was conducted with two different protocols, where one was run to over 6 million cycles based on AASHTO defined loading and the other to 2 million cycles with higher than AASHTO defined loading. Fatigue failure was observed in only one specimen that was subjected to the higher loading condition, providing a sense of fatigue life of this material. Fatigue failure mode initiated in flexural fiber rupture, which was different to monotonic tests under the same loading configurations. Bolted deck to steel stringer connection tests indicated failure modes in the FRP with strength values that were in certain configurations well below the strength of the bolts. For cases where the bolted FRP deck was counted on to provide lateral stiffness, such as the case in the raised configuration of the bascule span, the closed cell was found to have approximately twice the stiffness. The results of these tests provide valuable data that can be applied to FRP bridge deck designs that utilize bolted connections and open and closed cell deck configurations under high traffic volumes.
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Wireless Data Collection System

Wireless Data Collection System for Travel Time Estimation and Traffic Performance Evaluation
 
This report presents the results of the third and final research and development project of an implementable wireless travel time data collection system.  Utilizing Bluetooth wireless technology as a platform, the prior projects focused on data collection hardware and network communication implementation. In this project the processing and synthesis of collected data was addressed. Results and procedures that address data filtering, travel time sample calculation, calculation of travel time statistics, travel time forecasting are described.  Results for the use of collected data to estimate intersection performance are presented, as are the design and requirements for an automated travel time data collection system.  The report includes a users’ manual.
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Quantifying Safety Performance of Driveways on State Highways

Quantifying Safety Performance of Driveways on State Highways
 
This report documents a research effort to quantify the safety performance of driveways in the State of Oregon. In particular, this research effort focuses on driveways located adjacent to principal arterial state highways with urban or rural designations. This report includes safety performance functions (SPFs) that can be used to evaluate the safety impacts of various access management and driveway-related configurations on Oregon arterial corridors. The project team developed these safety metrics using statistical models and methodologies similar to those outlined in the Highway Safety Manual (HSM) published in 2010 by the American Association of State Highway and Transportation Officials (AASHTO). Instead of using a base condition SPF that included only segment length and traffic volume and then would need companion CMFs to fully analyze a corridor, the project team developed full model SPFs that do not require any additional adjustments. The resulting models varied for urban versus rural conditions, but type of land use and traffic volume were two consistently significant variables observed for both models. A companion “smart spreadsheet” accompanies this report to assist readers with implementation of the procedure.
 
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Mechanistic-Empirical Pavement Design Guide

Wireless Data Collection System for Travel Time Estimation and Traffic Performance Evaluation
 
The Oregon Department of Transportation (ODOT) is in the process of implementing the recently introduced AASHTO Mechanistic-Empirical Pavement Design Guide (MEPDG) for new pavement sections. The majority of pavement work conducted by ODOT involves rehabilitation of existing pavements. Hot mix asphalt (HMA) overlays are preferred for both flexible and rigid pavements. However, HMA overlays are susceptible to fatigue cracking (alligator and longitudinal cracking), rutting, and thermal cracking. This study conducted work to calibrate the design process for rehabilitation of existing pavement structures. Forty-four pavement sections throughout Oregon were included. A detailed comparison of predictive and measured distresses was made using MEPDG software Darwin M-E (Version 1.1). It was found that Darwin M-E predictive distresses did not accurately reflect measured distresses, calling for a local calibration of performance prediction models. Darwin M-E over predicted total rutting compared to the measured total rutting and most of the rutting predicted by Darwin M-E occurs in the subgrade. For alligator (bottom-up) and thermal cracking, Darwin M-E underestimated the amount of cracking considerably as compared to in-field measurements. A high amount of variability between predicted and measured values was observed for longitudinal (top-down) cracking. The performance (punch-out) model was also assessed for continuously reinforced concrete pavement (CRCP) using Darwin M-E's default (nationally calibrated) coefficients.
 
Four distress prediction models (rutting, alligator, longitudinal, and thermal cracking) of the HMA overlays were calibrated for Oregon conditions. It was found that the locally calibrated models for rutting, alligator, and longitudinal cracking provided better predictions with lower bias and standard error than the nationally (default) calibrated models. However, there was a high degree of variability between the predicted and measured distresses, especially for longitudinal and transverse cracking, even after the calibration. It is believed that there is a significant lack-of-fit modeling error for the occurrence ​of longitudinal cracks. The Darwin M-E calibrated models of rutting and alligator cracking can be implemented, however, it is recommended that additional sites be established and included in the future calibration efforts to improve the accuracy of the prediction models.​
 
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Cost, Emissions, and Customer Service Trade-Off Analysis in Pickup and Delivery Systems

Cost, Emissions, and Customer Service Trade-Off Analysis in Pickup and Delivery Systems 
 
This research offers a novel formulation for including emissions into fleet assignment and vehicle routing, and for the trade-offs faced by fleet operators between cost, emissions, and service quality. This approach enables evaluation of the impact of a variety of internal changes (e.g. time window schemes) and external policies (e.g. spatial restrictions), and enables comparisons of the relative impacts on fleet emissions. In an effort to apply the above approach to real fleets, three different case studies were developed. Each of these cases has significant differences in their fleet composition, customers’ requirements and operational features that provide this research with the opportunity to explore different scenarios. The research includes estimations of the impact on cost, CO2 and NOX emissions from fleet upgrades, the impact on cost, emissions, and customer wait time when demand density or location changes, and the impact on cost, emissions, and customer wait time from congestion and time window flexibility. Additionally it shows that any infrastructure use restriction increases cost, and emissions. A discussion of the implications for policy makers and fleet operators in a variety of physical and transportation environments is also presented.
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Asphalt Binder Grade Selection

Asphalt Binder Grade Selection and Ignition Oven Calibration Factors for HMAC with Recycled Asphalt Products
This study investigated several characteristics of laboratory-fabricated and plant-produced hot-mix asphalt mixtures containing various proportions of RAP and RAS with the principal objectives of developing a procedure for selecting the virgin binder grade used in such mixtures as well as a procedure for determining ignition oven calibration factors for mixtures containing these materials. Other objectives included developing recommendations for procedures to effectively and efficiently recover asphalt binder from RAS, batch and mix reclaimed materials with virgin materials, and for quality control and quality assurance testing.  The blending chart analysis procedure described in AASHTO PP 53 for selecting a virgin binder grade was selected as a starting point for evaluation purposes, but the attempt to validate the procedure was unsuccessful. Consequently, an alternate approach was recommended for further investigation.
 
ODOT’s current method for determining ignition oven calibration factors (TM 323) was evaluated using both laboratory prepared and plant-produced mixtures. Findings from this evaluation provided strong evidence to suggest procedural changes to the current method are unnecessary. Further, modification of ODOT’s current independent assurance parameter for asphalt binder content is not justified at this time. However, changes to the language in the test method to include RAS are needed and recommendations for these are provided.
 
Selection of procedures for extracting and recovering binder from RAS was accomplished through a literature search. Selection of procedures for QC and QA was accomplished in the same manner. However, detailed procedures for fabricating laboratory specimens containing RAS were not found. Consequently, taking into consideration existing procedures, new procedures were developed for batching and mixing specimens containing RAP, RAS, or combinations of RAP and RAS.

The applicability of using of nuclear density gauges to determine in-place density of mixtures containing RAS was also evaluated. Assessment was based on variability of density measurements obtained from nuclear gauges and from pavement cores.  Findings indicated no difference in the quality of measurements made on mixtures containing RAP and RAS versus those containing only RAP. ​
 
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Internal Curing of High-Performance Concrete for Bridge Decks

Internal Curing of High-Performance Concrete for Bridge Decks
High performance concrete (HPC) provides a long lasting, durable concrete that is typically used in bridge decks due to its low permeability, high abrasion resistance, freeze-thaw resistance and strength. However, this type of concrete is highly susceptible to the deleterious effects of both autogenous and drying shrinkage. Both types of shrinkage occur when water leaves small pores (< 50 nm) in the paste matrix to aid in hydration or is lost to the surrounding environment. Autogenous deformation (self-desiccation) occurs as the internal relative humidity decreases due to hydration of the cementitious material. Drying (and subsequent shrinkage) occurs when water is lost to the environment and continues until the internal relative humidity is equivalent to the ambient relative humidity. Typically, the magnitude of autogenous shrinkage is significantly less than that of drying shrinkage. These two types of shrinkage do not act independently, and the total shrinkage is the aggregation of the two shrinkage mechanisms, among other types of deformation. It is thus imperative to minimize the amount of shrinkage in restrained members, such as bridge decks, to reduce subsequent cracking potential. Various methods have been investigated to minimize both types of shrinkage. Two methods to date that have been reported to reduce shrinkage were selected for further research; internal curing using pre-soaked fine lightweight aggregate (FLWA) and a shrinkage reducing admixture (SRA).
 
The purpose of this study was to determine the long-term drying shrinkage performance of these two methods while reducing the current external curing duration of 14 days for new bridge deck construction as specified by the Oregon Department of Transportation. In addition to monitoring drying shrinkage, durability testing was performed on concrete specimens to ensure these shrinkage mitigation methods performed at levels similar, or superior, to concrete with the current mixture design. Freeze-thaw testing, permeability testing and restrained drying shrinkage testing were conducted. It was concluded that the pre-soaked FLWA and the SRA were effective at reducing the long-term drying shrinkage, but the combination of SRAs and pre-soaked FLWA was the most effective method to reduce long-term drying shrinkage for all curing durations (1, 7, and 14 day). Additionally, for durability testing, it was found that the use of SRAs performed the best in freeze-thaw testing, chloride permeability and restrained shrinkage when compared to the control.
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Damage Detection of Landslides

Real-Time Change & Damage Detection of Landslides and Other Earth Movements Threatening Public Infra 
  
Geologic hazards such as coastal erosion, landslides, seismic loading, etc. constantly threaten public highway construction and maintenance.  Repeat surveys using terrestrial laser scanning (TLS, ground-based LIDAR) enable rapid 3D data acquisition to map, see, analyze, and understand the processes generating such problems.  Previously, change detection and analysis between scan surveys was conducted during post-processing upon return to the office, instead of while collecting data in the field.  Change detection in the field improves the effectiveness and efficiency of the field investigation.  We have developed a new algorithm that quickly geo-references scans upon field acquisition and simultaneously performs change detection by comparing these newly acquired scans to baseline models.  
  
This algorithm has been integrated with a simple, intuitive GUI that enables change detection to be completed quickly (<1min per scan) while data are being acquired in the field.  This software has also been enhanced to ensure a productive workflow.  Implementation and testing of the algorithm is underway at several sites that have been problematic for state agencies.  Two test sites showing active movement are along Highway 101 in Oregon.  These are the Spencer Creek Bridge site and the Johnson Creek landslide.  An additional trial site is the US20 Pioneer-Eddyville highway realignment project, where several active landslides and surficial slope failures of embankment fill slopes have significantly disrupted construction efforts.  Substantial baseline information at these sites was collected, which will be useful for future Oregon Department of Transportation and Oregon Department of Geology and Mineral Industries studies.  
  
Performing change detection in the field offers several significant advantages to current post-processing workflows.  First, field change detection serves as an augmented reality system, enabling field crews and researchers to see immediate results, on site, so that they are able to make key observations while present at the site, instead of being reliant on their personal memories or notes.  Second, and importantly, it can improve the overall efficiency of the survey.  When this information is available to the operator during field data acquisition, areas of minimal change can be quickly surveyed at coarser resolutions and areas of substantial change can be scanned at higher resolutions.  This also translates into reduced processing time and data maintenance, which are currently significant hurdles for analyzing 3D laser scan datasets.  Finally, this method provides immediate validation and quality control of the RTK GPS and laser scan data being collected, leading to more confidence in the acquired data and allowing any issues to be resolved directly in the field. ​
 
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Alternative Mobility Metrics

Development and Sensitivity Testing of Alternative Mobility Metrics 
  
The Oregon Highway Plan’s (OHP) mobility policies guide various planning and programming activities of the Oregon Department of Transportation (ODOT). Among these activities are ODOT’s land use change review responsibilities under the Transportation Planning Rule, as adopted by the state’s Land Conservation and Development Commission. This report examines supplemental transportation performance metrics beyond the volume-to-capacity metric that currently supports OHP mobility policies. Selected supplemental metrics are empirically analyzed using a travel demand model calibrated for a Medford, Oregon study area. 
 
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Near-Surface Mounted CFRP Bars

Strength and Durability of Near-Surface Mounted CFRP Bars for Shear Strengthening Reinforced Concrete Bridge Girders 

During the interstate expansion of the 1950s, many conventionally reinforced concrete deck girder bridges were built throughout the country. These aging bridges commonly exhibit diagonal cracking and rate inadequately for shear, thus they are candidates for shear strengthening to extend their useful life. Carbon fiber reinforced polymers (CFRP) are emerging as effective materials for strengthening and rehabilitating such bridges. Near surface mounting (NSM) is a newer technique for application of CFRP for retrofitting bridge members that provides advantages over other strengthening techniques. The technique is still new and uncertainties remain regarding strength, long-term durability, and design including the influence of member proportions, flexural reinforcing steel, and CFRP spacing. Bridge girders retrofitted with NSM-CFRP may be exposed to millions of load cycles and environmental conditions and the influence of these exposures on performance are not established. To address these issues, laboratory tests were performed on ten full-size reinforced concrete girders, representative of in-situ bridge members, to determine the performance of NSM-CFRP retrofitting for shear strengthening. One of the specimens was exposed to fatigue loading, two were subjected to environmental exposures, and one was subjected to combined environmental exposure and fatigue loading. Results indicated that NSM-CFRP retrofitting provided significant shear capacity increases, and the high-cycle fatigue and environmental exposures considered did not adversely affect the strength or behavior of the girders. Environmental exposures of some of the adhesives considered did show somewhat reduced performance; therefore, careful selection of materials is important to ensure performance over the expected lifetime. Recommendations for shear strength design with NSM-CFRP are made.
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Developing Safety Performance Measures for Roundabout Applications

Developing Safety Performance Measures for Roundabout Applications in the State of Oregon​

This report documents the research effort to quantify the safety performance of roundabouts in the State of Oregon.  The primary goal of this research is to provide the Oregon Department of Transportation (ODOT) with safety performance functions (SPFs) that can be used to evaluate the safety performance of single-lane, four-leg roundabouts. These safety metrics generally conform to the statistical models and methodologies similar to those outlined in the Highway Safety Manual (HSM) published in 2010 by the American Association of State Highway and Transportation Officials (AASHTO).
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Implementing Speed Reductions in Workzones

Implementing Speed Reductions at Specific Interstate Workzones from 65 MPH to 35 MPH
 
Interstate preservation projects are commonly conducted at night and often require working in close
proximity to ongoing traffic. Vehicle speed and speed variability in work zones is inextricably connected
to the work zone design and the selected traffic control devices. To provide guidance on how to
effectively and efficiently reduce traffic speeds, the Oregon Department of Transportation conducted
a research study to investigate the impact of selected traffic control devices on vehicle speed within
highway paving project work zones. The research centered around two case studies on multi-lane
paving projects in Oregon. On each case study, the researchers implemented multiple traffic control
devices (PCMS signs, radar speed display, police officer presence, tubular markers and drums on
both sides of travel lane) and evaluated their impact on vehicle speed, construction productivity,
cost, and motorist and worker safety. A police officer parked on the site was found to effectively
reduce traffic speeds and should be used if available and feasible. The research findings also
suggest using a combination of temporary reduced speed limit signs, radar speed monitoring
display, and PCMS signs on both trailers and rollers. Further research is needed to validate the
research findings and better identify the advantages of one traffic control device over another.
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Implementation of the Fluvial Performance

Effect of the Implementation of the Fluvial Performance Standard on Maintenance of Bridges and Culverts
 
The objective of this project was to determine what factors influence maintenance cost of Oregon Department of Transportation (ODOT) stream-crossing structures. Data acquired for the project included structure characteristics, stream characteristics, peak flows, and 1996-2010 maintenance costs for five maintenance activities. Nine factors were selected to investigate: active channel width, ratio of valley width to active channel width, number of hardwoods, number of conifers, ratio of bridge length to active channel width, ratio of longest bridge span to active channel width, and the ratio of peak flow to average flow both the year of maintenance and the year prior to maintenance. Possible relationships were investigated through the use of scatter-plots and bar-charts. Potential problems with the datasets may have prevented the discovery of relationships. The average maintenance interval and the average annual cost of maintenance over the fifteen-year period were both found to be very low.
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Delivering Better Value for Money: Determining Outsourcing Feasibility

Delivering Better Value for Money: Determining Outsourcing Feasibility and Standard Pricing Methods

Two databases of engineering hours were developed to aid contract administrators in negotiating consultant hours for contracts for preliminary engineering (PE) and/or construction engineering (CE) services. The local agency projects database includes 181 projects. The OTIA III bridge projects database includes 124 bridge repair and replacement projects. Databases include estimated consultant hours by task for the projects, and descriptive information for the projects. The databases were analyzed to identify relationships between project characteristics and consultant contract hours required. Results of these analyses are presented. A procedure for use of the databases in the negotiation process is
presented. In addition, general information relating to procurement of personal services contracts is presented. This information was obtained from a literature review, the Oregon Department of Transportation, and other transportation agency personnel.
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Mobile Barriers

Evaluation of a Mobile Work Zone Barrier System
 
A high percentage of highway maintenance activities and some construction activities are performed in a travel lane, median, or shoulder while the public travels by at relatively high speeds in very close proximity to the workers. Work zone traffic control efforts include safety measures for the workers, but current capabilities for short duration work zones can be improved in order to increase the protection of the workers. A recent advancement in work zone safety is a mobile barrier system that consists of a motorized tractor/trailer combination, and can provide complete isolation of the work area for a distance of up to 100 feet. The research presented in this report involved evaluating a mobile barrier in a variety of work zone environments, leading to a determination of its benefits and limitations to guide ODOT in future work zone safety strategies/investments. A benefit of using a mobile barrier system is the added safety provided by the isolation of workers from errant vehicles. Anticipated benefits also include: improved efficiency of work zone setup and removal; improved efficiency of the work activity as the mobile barrier can be equipped with lights, generators, variable message signs, and TMAs; and improved mobility of the work zone where multiple finite work areas are involved.
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