Indiana Department Of Transportation Research Articles

Line-of-Sight Wall versus Conventional Noise Wall for Traffic Noise Abatement: Field Performance Comparison

AbstractThe constructed cost of conventional noise walls is about $2 million per linear mile. In many areas, the cost-effectiveness criteria of $25,000 per benefited receiver are exceeded so that these areas are not eligible for federal-aid funding for noise abatement. Consequently, the residents in these areas are dissatisfied that no noise reduction measures are provided to them. To address these issues, the Indiana Department of Transportation evaluated the line of sight (LOS) wall to improve customer satisfaction at a less expensive cost. Three different LOS walls were installed and compared with the conventional concrete noise wall. Such information will be useful to state departments of transportation not only to develop specifications for LOS walls, but also to upgrade their traffic noise policy to improve customer services.

Using Enhanced Econometric Techniques to Verify the Service Life of Asset Interventions

In the current era, the highway environment is characterized by funding limitations, aging facilities, and increasing user expectations. In light of these trends, asset managers at most highway agencies have a fiduciary responsibility to apply management strategies and practices that not only are most cost-effective in a life-cycle context but also are in the best interests of taxpayers and highway users. To identify and implement effective rehabilitation strategies and practices, highway agencies need to verify information that was typically based on expert opinion, with reliable asset performance prediction tools and treatment service life estimates. This study provides an enhanced methodology to analyze pavement rehabilitation data and to develop estimates and ranges of treatment service lives. Pavement rehabilitation data typically consist of repeated measurements that form an unbalanced three-level nested structure, making analysis quite challenging. In this study, mixed linear modeling techniques are deployed to accommodate this structure and thus lead to less biased estimations compared with traditionally used approaches. The developed framework is applied to quantify the effectiveness of seven common rehabilitation treatments applied by the Indiana Department of Transportation in regard to their service lives and to validate the treatment service life values presented in the agency's current design manual.

A model for life-cycle benefit and cost analysis of highway project

Economic analysis is a critical component of a comprehensive project or program evaluation methodology that considers all key quantitative and qualitative impacts of highway investments. It allows highway agencies to identify, quantify, and value the economic benefits and costs of highway projects and programs over a multiyear timeframe. This research was conducted to provide the Indiana Department of Transportation (INDOT) with a uniform economic analysis methodology. The developed economic evaluation model applies the methodology of life-cycle benefit cost analysis to perform economic analysis for proposed highway projects. As a result of this research, an Excel based computer program, the Indiana Highway Economic Evaluation Model (IHEEM), was developed to provide a convenient tool for INDOT personnel to implement the method. A probabilistic model was developed in IHEEM to provide an alternative option for economic analysis in addition to the deterministic model described in the previous chapters. Users of IHEEM can choose either one or both of deterministic and probabilistic methods in economic analysis of highway and bridge improvement projects. In the model, traffic volume and construction cost are treated as random variables with certain statistic characteristics. In the probabilistic process, the random variable is assigned to an appropriate distribution with an estimated coefficient of variance (CV). A simulation process is repeated for a user defined number of times by random numbers to generate an output with statistic ranges and confidence levels.

Risk-Based Protocol for Inspection of Transportation Construction Projects Undertaken by State Departments of Transportation

In the last decade, the state departments of transportation in the US have experienced an increase in their construction projects, while the level of their in-house inspection staff and resources has either remained the same or declined. Previous studies have found that one strategy that may reduce the inspection workload is prioritizing construction activities for inspection. However, reducing the number of inspections also has its risks, such as functional failures and reduced design life. Thus, available inspection resources should be allocated to the activities with significant risk consequences if inspection is reduced. The objective of this paper is to develop a risk-based inspection protocol to facilitate efficient allocation of available inspection resources to minimize the risks associated with reduced inspection. First, the risk consequences associated with reduced inspection are identified for various construction activities linked to transportation projects. Based on data collected from 23 state departments of transportation, 58 engineers and inspectors from the Indiana Department of Transportation and 20 inspection consultants in the Midwest, the subjective perceived probabilities associated with the occurrence of each risk consequence are encoded by using fuzzy analysis, from which the risk impacts due to reduced inspection are obtained. The construction activities are prioritized based on the risk impacts associated with reduced inspection into five priority levels. The greater the risk impacts are as a result of reduced inspection, the higher the priority would be for inspection of that activity. Thus, the proposed protocol can be used for resource allocation based on risk impacts. The proposed list of prioritized construction activities can assist project and program managers in state departments of transportation in better allocating their limited inspection resources while reducing the risks due to reduced inspection.

Leveling Process of Annual Budgetary Requirements for Pavement Preservation

AbstractThis paper presents a model for leveling annual budgetary requirements (ABRs) for pavement preservation programs over a multiyear analysis period. Given the information such as the candidate pavement preservation projects, associated costs, application years, and time floats to be shifted, the presented leveling process adjusts the application years of the projects to minimize the variance among ABRs. The minimum moment method is modified considering the dummy period that is to shift preservation projects within their time floats and additional constraints for the leveling process. To validate the leveling model, this study uses Indiana Department of Transportation (INDOT) pavement preservation projects as a case study that consists of a total of 193 projects over a three-year analysis period between 2010 and 2012. As a result of the case study, the leveling process provides relatively consistent ABRs over the three-year analysis period for INDOT. Therefore, the major contributions of this researc...

Evaluation for Microsurfacing as Pavement Preservation Treatment

AbstractOver the years, the Indiana Department of Transportation (INDOT) has changed its emphasis from construction to preservation of public highways. As such, there is great interest in assessing cost efficacy of a pavement preservation strategy. This paper aims to present the functional and structural benefits of microsurfacing applications at highway sections in Indiana. To achieve this goal, comprehensive monitoring and data analysis was performed using the pavement condition rating (PCR), structure number (SN), and surface roughness [international roughness index (IRI)] for in situ performance evaluation. According to the deflection and roughness analysis, an improvement was observed in SN and IRI during the early life of the pavement. Furthermore, no significant difference was obtained over the following 2 years. Application of the microsurfacing resulted in a significant rise in PCR and SN and decline in IRI. A similar result was found at the resurfacing site. Pavement with microsurface sections h...

Analysis of Crash Frequency in Work Zones with Focus on Police Enforcement

Highway work zone safety has been a concern nationwide and will likely draw ever increasing attention as more highway funds are invested in the maintenance of existing highways. To improve work zone safety, the Indiana Department of Transportation (DOT) established a special fund for work zone patrolling, and this study was commissioned to help the Indiana DOT achieve the maximum safety benefits within its budget constraint. With help from the Indiana DOT, a survey of project engineers was conducted to collect work zone information. The findings from the survey were linked with other available data. A random-effect negative binomial model was developed to identify the contributing factors and to estimate crash frequency in highway work zones. The results from the model provided insight for better understanding of crashes in work zones. Various factors, including roadway information, traffic volume, work zone–specific features, and police presence, were identified as things that affect crash frequency in work zones. These and other findings will be used to plan police enforcement activities in future Indiana DOT work zones.

Field Evaluation of Surface Friction Performance of Chip Seals in Indiana

Chip seal has been widely used as an effective surface treatment for pavement preservation. The Indiana Department of Transportation (DOT) chip sealed a total of 373 lane mile pavements in 2008 and 700 lane mile pavements in 2009. However, many issues, such as the optimal use of local materials and new aggregates, remained unsolved. No original information was available at the time for Indiana DOT engineers to assess the performance of chip seal pavements. A research study was initiated by the Indiana DOT to evaluate the field performance of chip seal pavements, particularly the surface friction properties. Eighteen chip seal projects were selected as the test sections for this study. Field testing was conducted to measure pavement surface friction and texture properties. The true surface friction numbers were identified for chip seals after 12 months of service. The variation of surface friction on chip seals was analyzed. Factors affecting chip seal surface friction, such as aggregate, traffic volume, and existing pavement condition, were identified and examined. Three traffic levels were defined for better chip seal application. The international roughness index on the existing pavement affected chip seal friction performance. A criterion was recommended for assessing the friction performance of chip seal and identifying the possible failure of a chip seal.

Can Soy Methyl Esters Improve Concrete Pavement Joint Durability?

Although many concrete pavements provide excellent long-term performance, some pavements (primarily in the Midwest) have shown premature deterioration at the joints. This premature deterioration is a concern because such deterioration can shorten the life of pavements that are otherwise functioning well. Previous work has hypothesized that these joints may be susceptible to preferential fluid saturation, which can lead to freeze–thaw damage or chemical degradation. This work examines the use of soy methyl ester–polystyrene (SME-PS) blends as a method to reduce the rate of fluid ingress into the pore system of the concrete and thereby make the concrete more resistant to deterioration. SME-PS is derived from soybeans and has demonstrated an ability to reduce fluid absorption in concrete when used as a topical treatment. A series of experiments was developed to evaluate the effectiveness of various dosage rates of SME-PS for increasing concrete durability at pavement joints. The experiments show that SME-PS reduces fluid ingress, salt ingress, and the potential for freeze–thaw damage. As a result of the positive experimental results, the Indiana Department of Transportation is conducting field trials that use SME-PS on concrete pavements that are beginning to show signs of premature deterioration with the expectation that SME-PS will extend the life of the joints and thereby reduce maintenance cost and extend the life of concrete pavements.

Durability of Pavement Concretes Made with Recycled Concrete Aggregates

There is a growing trend to replace the traditional ingredients of concrete pavement mixtures with more sustainable materials from a perspective of both the cost of raw materials and the carbon dioxide footprint. The availability of quality natural aggregates, which make up about 70% to 80% of concrete (by volume), is becoming more limited because of environmental restrictions on quarrying operations and longer hauling distances. The other major concern is disposal of old concrete pavements, which unless used as fill or base material for construction of new roadways, will have to be placed in the landfills. In this study, recycled concrete aggregates (RCA) obtained from crushing old concrete pavement were used as coarse aggregates at 0%, 30%, 50%, and 100% replacement levels (by mass) for natural virgin aggregates (NVA). Concrete mixtures were designed and produced to meet the concrete pavement requirements for air content, slump, and flexural strength stipulated by the Indiana Department of Transportation. All concrete mixtures were produced with 18.5% to 20.0% of the cement replaced (by mass) with ASTM C618 Class C fly ash. The physical and mechanical testing involved evaluation of slump, air content, and development of both flexural and compressive strengths. In addition, durability was assessed with the freeze–thaw test, scaling test, rapid chloride permeability (RCP) test, and non–steady state migration test. The most advantageous dosages for replacing NVA with RCA for concrete pavements were found to be 50%, on the basis of fresh concrete properties and the results of strength and durability tests. The applicability of electrical impedance spectroscopy for quick performance appraisal is presented on the basis of the experimental relationship between the RCP charge and bulk resistance of concrete.

In-Service Performance Evaluation of a Cable Median Barrier System on Interstate Highways

Under an experimental features study requested by the Federal Highway Administration, the Indiana Department of Transportation installed a proprietary cable median barrier system, i.e., the Brifen four-rope wire rope safety fence (WRSF), to assess issues in installation, maintenance, and repair of this WRSF system and to evaluate its in-service performance. The WRSF system was installed at two different sites, respectively. A total of 157 median crashes were examined to evaluate the safety performance of the WRSF system in terms of the effectiveness in intercepting errant vehicles and crash outcomes. Field visits were conducted to identify possible improvements to the layout of the WRSF system according to the roadway configurations. The construction and repair costs were examined to provide useful information for cost-effectiveness analysis. Models were developed to enable an in situ estimate of the damage to the WRSF system after each crash. This paper presents the process and findings for the field installation, safety evaluation, and cost analysis.

Purdue Researchers Develop Guidelines For Integrating Tires into Road Projects

In the quest to perfect the formula for using shredded tires as a construction material in roadway projects, researchers at Purdue University and the Indiana Department of Transportation are determining how the rubber should meet the road.

Creation of Truck Axle Load Spectra Using Weigh-in-Motion Data

To assure a smooth transition from the existing pavement design methods to the new mechanistic-empirical design method in the Indiana Department of Transportation, a study was conducted to create truck traffic inputs and axle load spectra of major interstate and state-owned highways in Indiana. The existing pavement design method is based on the equivalent single-axle loads (ESAL), which converts wheel loads of various magnitudes and repetitions to an equivalent number of "standard" or "equivalent" axle loads. The new design method uses axle load spectra as the measure of vehicle loads on pavements. These spectra represent the percentage of the total axle applications within each load interval for single, tandem, tridem, and quad axles. In this study, the truck traffic and axle load spectra were developed based on the historical traffic data collected at 47 sites with weigh-in-motion technology. The truck traffic information includes hourly, daily, and monthly distributions of various types of vehicles and corresponding adjustment factors, the distributions of the number of axles of each type of truck, the weights of the axles, the spaces between the axles, the proportions of vehicles on roadway lanes, and the proportions of vehicles in driving directions. This paper presents the truck traffic and axle load spectra generated from the weigh-in-motion sites as required by the new pavement design method.

Balancing Engineering Criteria and Historic Significance to Preserve Select Bridges

This paper describes Indiana's efforts to prioritize historic bridges for preservation with the use of a systematic analysis that considers both relative historic significance and engineering condition. The state's historic bridge preservation program was initiated in 2006 with the execution of a programmatic agreement (PA) between FHWA, Indiana Department of Transportation (DOT), Indiana State Historic Preservation Officer (INSHPO), and Advisory Council on Historic Preservation. The PA streamlines the Section 106 regulatory process and allows Indiana DOT and local agencies to manage the state's population of historic bridges effectively and programmatically instead of using an inefficient project-to-project approach. The most innovative aspect of Indiana's historic bridge program is the establishment of a prioritization method. Each historic bridge is evaluated and then classified as either select, meaning the bridge is an excellent example of its type statewide and is suitable for preservation, or nonselect, meaning the bridge is not the best example of its type and may not be suitable for preservation. Upon agreement by FHWA, Indiana DOT, and INSHPO, lists of select and nonselect bridges were issued in March 2010. The methodology for identifying and prioritizing individual bridges is explained, highlighting the effort to achieve balance between historic significance and engineering and economic criteria, including functionality, safety, feasibility, and cost-effectiveness. Indiana DOT also developed standards for treating historic bridges on low-volume roads. If historic bridge rehabilitation can meet the standards, then rehabilitation for vehicular use must be implemented.

Development of Specification for Accelerated Approval Process of Flowable Fill Mixtures

The flowable fill is a self-compacting cementitious material used primarily as an alternate backfill in lieu of compacted soil. In general, from the applications point of view, the flowable fill mixtures can be divided into two categories: removable fills (mixtures that require future excavation) and nonremovable fills. The specifications for the removable type of flowable fills typically limit both the minimum and the maximum 28-day compressive strengths, thus increasing the time needed for completion of the approval process. This paper presents set of accelerated flowable mixture approval requirements which can be performed at earlier ages (3 and 14 days) and are based on blow count number from the lightweight dynamic cone penetrometer (DCP). These requirements can be used as an alternative to the 28-day compressive strength testing and are considered for adoption by the Indiana Department of Transportation. They were developed based on both, laboratory and field tests which included 14 different mixtures. The DCP-based approval is preferred, as (unlike the compressive strength) the test can be performed in situ and thus better represents the characteristics of flowable fill.

Evaluation of Prestressed Concrete I-Girder Bridge Design Software with NCHRP Process 12-50

NCHRP Process 12-50 was used to evaluate and verify prestressed concrete bridge design software commonly used in Indiana. A test bed of 40 bridge structures was developed with input from practicing engineers and Indiana Department of Transportation (INDOT) specialists. The test bed included 20 simple-span and 20 multispan bridges. The primary parameters were bridge span, girder spacing, section type, strand pattern (straight or draped), and concrete strength. The remaining parameters were held constant with practical or consensus values provided by engineers or the INDOT bridge design manual. The section types included were AASHTO Types II, III, and IV and Indiana modified Bulb-Tee beams (54–78 in. deep). An indigenous computer program, PURDUE PSBD, was developed to implement the bridge design calculations specified in the AASHTO LRFD Bridge Design Specifications, which are currently endorsed by the INDOT bridge design manual. Both CONSPAN (the most common bridge design software in Indiana) and PURDUE PSBD generated calculation results for the complete test bed of bridges. The output from both computer programs was compared to identify assumptions and discrepancies from the AASHTO LRFD specifications. These comparisons indicated excellent agreement between the results from both programs for ( a) concrete stresses and deflections at service-level loads, ( b) nominal flexural strength, ( c) nominal shear strength, and ( d) initial camber and deflections. The test bed of bridge structures and the PURDUE PSBD program developed in this research are recommended for evaluating and verifying other bridge design software.

Multi‐round procurement auctions with secret reserve prices: theory and evidence

AbstractWhen a secret reserve price is used in an auction, the auctioneer cannot guarantee that the good can be sold out at the auction, and can reauction the unsold objects in the next round. Motivated by this interesting feature observed in the procurement auctions organized by the Indiana Department of Transportation, we construct a dynamic bidding model in multi‐round procurement auctions with secret reserve prices and evaluate how the release of the auctioneer's reserve price affects bidders' bidding behavior and the auctioneer's expected payment. Our theoretical model predicts that the equilibrium bids uniformly decline over stages, and the numerical analysis of our model indicates that hiding the reserve price may be better than announcing it for the auctioneer under some specifications of underlying distributions. We develop an empirical model with bidders' discount factor equal to zero to recover the unknown structural parameters and to conduct counterfactual analyses. Copyright © 2008 John Wiley & Sons, Ltd.

Use of in Situ Tests in Compaction Control of a Bottom Ash Embankment

Since 1994, the Indiana Department of Transportation has constructed numerous recycled materials projects that use bottom ash, fly ash, foundry sand, crushed glass, and tire shreds in transportation facilities. All these projects were constructed in accordance with procedural specifications based on conventional compaction control tests such as the nuclear gauge. However, the nuclear gauge does not give accurate density and moisture content results because of the presence of numerous elements in recycled materials. In addition, sand cone tests are cumbersome and time-consuming. There is a need to develop criteria for in situ test methods such as the dynamic cone penetration test and lightweight deflectometer (LWD) testing. Once an initial criterion is established, criteria for compaction control of similar recycled materials can be developed. In a study, a test pad using coal ash was constructed with a combination of roller passes. On the basis of the results of dynamic cone penetration and LWD tests conducted in the test pad, in conjunction with a combination of roller passes, the criteria for compaction control of bottom ash was provided for the construction of the remaining 11-m-high embankment. The subsequent construction monitoring and postconstruction evaluation of the bottom ash embankment revealed that the criteria are very effective.

Implementation of Lane-by-Lane Detection at Actuated Controlled Intersections

Previous work with lane-by-lane detection has shown efficiency gains during periods of moderate to low volume, as well as a decrease in overall intersection delay when lane-by-lane detection is compared with traditional movement-based detection. This research extends that work with the implementation of lane-by-lane detection at the Indiana Department of Transportation's test bed intersection in Noblesville, Indiana. Over a 3-week period with traditional movement-based detection, green interval lengths, volume-to-capacity (v/c) ratios, and cycle lengths were computed for all eight phases. Detection and controller settings were changed to implement lane-by-lane detection on the multilane movements at the test bed, and the same measures of effectiveness were calculated for 3 weeks of lane-by-lane detection. During free operation with low to moderate volume, statistically significant decreases in green durations and cycle times, as well as statistically significant increases in v/c ratios, were observed on movements with lane-by-lane detection. These implementation results corroborate previous simulation results.

Realistic Approach for Enhancing Reliability of Pavement Surface Friction Testing

Abstract This paper presents the state-of-the-practice by the Indiana Department of Transportation (INDOT) in enhancing the reliability of pavement friction testing with the ASTM Standard E 274-97 [1] locked wheel tester. In order to detect the potential changes in system performance, INDOT conducts weekly and monthly system verification on a special friction test track. A multiparameter method has been used in assessing the performance of the locked wheel tester. This method cross examines the sample mean, the standard deviation, and the coefficient of variations of the friction measurements saved in a dynamic friction database that is upgraded after each verification testing. It was found that the system performance of the locked wheel tester varies with the type of test tire and pavement surface characteristics. The smooth tire produces greater friction variations than the ribbed tire. As pavement surface becomes rougher, friction variations decrease. A realistic approach has been established for verifying system performance.