Jay K Lindly

Balancing Private and Public Interests in Public-Private Partnership Contracts Through Optimization of Equity Capital Structure

Capital structure and revenue-sharing agreements lie in the essence of balancing public and private interests in public–private partnership (PPP) contracts. In the United States, many PPP projects may not be fully self-financed through tolls or other user fees because of insufficient revenue streams. With a limited debt capacity secured by toll revenues, most PPP projects must be supported by both private equity investments and public funds. The equity structure is critical in a PPP contract because it implies risk and profit sharing and therefore provides a mechanism for private incentive and protection of the public interest. This paper presents a structured approach to determining the debt–equity investment in PPP projects. Scenarios are generated by using linear programming and probability programming models to reach the optimal equity structure under risk and uncertainty. The I-10 connector project is used as a case study to demonstrate the optimization process. The model is especially useful for public agencies to (a) estimate the range of private equity investment, (b) determine the target equity structure, and (c) document the benefits and costs of private financing for a successful PPP contract.

Impact of electric vehicles on electric power generation and global environmental change

Abstract The transportation industry is a major contributor to greenhouse gas and pollutant emissions. Of particular significance is the fleet of private vehicles powered by internal combustion engines utilizing petroleum-based fuels. The subject project was initiated to develop methodology to assess the impact of vehicle fleet electrification on electric power generation and global environmental change. While vehicle electrification will reduce vehicle emissions, the recharging energy will be generated at utility generation sites where emissions will increase. The project included a case study for Alabama. The vehicle emissions fleet model is based on the EPA software mobile 5a and employs Alabama Department of Transportation data as inputs to the case study. Electric vehicle penetration effects on vehicle emissions are computed by linear scaling of the base-case emissions. Power plant quarterly emission data from the EPA were employed in the case study for the State of Alabama. Values for feedstock and fuel emissions were taken from greet 1.5 to complete the fuel cycle calculations. In the 10% EV penetration Alabama case study, all light-duty vehicle emissions are reduced by 10%, and the total (light-duty vehicle and utility) emissions for the principle greenhouse gas CO2 were altered by −1.79%. Emissions for NOx and SO2 were altered by −4.37%, and +1.44%, respectively.

Estimating Permeability of Untreated Roadway Bases

Laboratory testing and statistical analysis of the resulting data to determine the effects of top size, aggregate gradation, and porosity on the permeability of unbound roadway base layers are described. Three different types of aggregates were tested: crushed limestone, crushed granite, and uncrushed river gravel. Top sizes of 19 mm (0.75 in.) 25 mm (1.0 in.), 38 mm (1.5 in.), and 63 mm (2.5 in.) were used. A total of 90 permeability tests were performed using permeameters of 15.2 cm (6 in.) and 30.5 cm (12 in.) in diameter. A statistical method was used to arrive at a first-order multiple regression equation to predict the coefficient of permeability of untreated, dense-graded or open-graded bases in the range of 0.004 to 0.7 cm/sec (1,000 to 2,000 fpd) using the void ratio of the sample and the percent by weight of materials that pass the 0.6 mm (No. 30) and the 0.075 mm (No. 200) sieves. Predicted permeabilities using the equation were compared to the predicted permeabilities using the Hazen equation ...

Using NDT to calculate the 1986 AASHTO guide subgrade effective resilient modulus

The research reported assessed a major change in the 1986 AASHTO Guide for Design of Pavement Structures. The soil support value was replaced with subgrade effective resilient modulus (M R ) in flexible pavement design. M R was introduced into the 1986 AASHTO Guide as part of an overall shift to the use of elastic modulus as the indicator of pavement layer structural capacity. Because subgrade modulus changes when the subgrade moisture content changes or when the subgrade freezes, M R must reflect the combined effect of the modulus values from all seasons of the year. AASHTO suggests that the spring thaw modulus may be as low as 20 to 50% of the summer modulus. NDT testing was performed during the spring thaw and summer seasons of 1986 on 15 Indiana flexible pavements with subgrades ranging from high plasticity clays to sands. Deflections from sensors 5 ft (152 cm) and 7 ft (213 cm) from the load plate were recorded for use in seasonal subgrade resilient modulus determination as provided by AASHTO. M R for each of the 15 pavements was determined using the following seasonal moduli as inputs: spring thaw and summer moduli as calculated from NDT deflections, spring/fall wet modulus interpolated between spring thaw and summer moduli, and winter modulus estimated as recommended by AASHTO. The research yielded the following findings for the conditions present in Indiana in 1986: contrary to expectations, the typical spring thaw modulus value was not dramatically lower than the summer modulus value; and summer modulus values were close enough to M R values that they may be used to approximate M R if spring thaw, spring/fall wet, and winter data are not available.

Seat Belt Use on Alabama School Buses: Preliminary Results of Pilot Study

The Alabama State Department of Education commissioned a study of school bus seat belt use on the basis of 12 buses (less than 1% of the fleet) equipped with seat belts and digital camera systems. The initial year of the study established baseline rates for normal situations. About 64,000 pupil observations were gathered from 11 buses on Tuesday through Thursday afternoon routes and from one control bus on Monday through Friday morning and afternoon routes. Afternoon route seat belt use was estimated to be 65.9% on the basis of 44,000 of the observations made. Given the small sample size, this value should be considered representative of the fleet but not exact. Belt use varied widely from bus to bus (94.5% to 4.8%). The degree of scatter was confirmed by large values of the coefficient of variation. Trends were documented for variation by day of week, morning versus afternoon, time on route, effects of bus aides, and changes in use over the school year. The findings confirmed the opinions of national experts and Alabama pupil transportation managers. High seat backs blocked the view of drivers as they tried to control pupil conduct and enforce seat belt use. The researchers of the University Transportation Center for Alabama examined digital images of pupils on the buses, but they could determine whether a seat belt was used only 65% of the time. While driving, bus drivers are able to see far fewer pupils: it is unrealistic to expect the drivers to enforce seat belt use.

Overview of 511 traveller information systems

The USA is composed of 50 states. Currently, 13 USA states and five urban areas have implemented the 511 traveller information system, reaching 50 million citizens (16% of the population). Thirty-one other states have received federal government grants to plan and implement 511 systems. When the system is fully deployed, motorists anywhere in the nation will dial 5-1-1 on landline or cellular phones and receive interactive, voice recognition-based, computerised information concerning construction activities, crash incidents, congestion and weather conditions for requested routes. The same information is available on internet sites accessible via standard internet browsers. The standards of 511 ensure that content and format are consistent throughout the country, which in the future will allow computerised sharing of data between systems. The 511 systems information allows motorists to plan their routes to minimise congestion and maximise safety for the price of a local telephone call.

Planning and Implementing a Nondestructive Pavement Testing Program

Planning and implementing a nondestructive testing (NDT) program for pavements is an interesting and often frustrating task. The authors of this paper perceived a need to summarize their experiences while using four NDT devices to test pavement sections on the federal-aid interstate and primary highway systems in Indiana. The lessons learned during the planning and execution of the project can be instructive to organizations planning similar studies. It will be of particular interest to those persons who have little experience conducting a project of this nature. Many of the basic concepts of planning, organizing, and conducting an NDT program are included. Personal experiences of the authors are given to help reinforce these concepts.

Development of an Overlay Design Procedure for Flexible Pavements in Indiana: Executive Summary

A procedure for designing the thickness of asphaltic concrete overlays of flexible pavements was developed at Purdue University in response to a request from the Indiana Department of Highways (IDOH). The research included testing on 30 flexible pavement test sections. Two approaches to the problem were taken: an empirical approach which calculates the overlay thickness required to provide functional performance (ride quality and resistance to distress) over the life of the pavement, and a structural overlay method which calculates thickness required to prevent structural failure. Flexible overlay design Method 2 of the 1986 AASHTO Guide for the Design of Pavement Structures was selected for structural capacity design. Method 2 uses nondestructive testing (NDT) deflection data input to calculate overlay thickness. A negative value for overlay thickness indicates that sufficient structural capacity is present without adding an overlay. The functional performance approach used Indiana flexible pavement historical data to produce a regression equation relating overlay thickness to traffic, design life oil the overlay, pavement condition at the end of the design life, and estimated subgrade California bearing ratio. Various NDT deflection measurements, climate zone data, and pavement layer thickness variables were included in a variety of empirical analyses, but they were not significant in the analyses. Simultaneous use of the two design methods was recommended to IDOH. If values from both methods are positive, the larger value governs the design. If the structural value is negative, a thickness equal to the functional performance design may be milled and recycled back to the pavement.

Development of an Overlay Design Procedure for Flexible Pavements in Indiana

A procedure for designing the thickness of asphaltic concrete overlays of flexible pavements was developed at Purdue University in response to a request from the Indiana Department of Highways (IDOH). The research included testing on 30 flexible pavement test sections. Two approaches to the problem were taken: an empirical approach which calculates the overlay thickness required to provide functional performance (ride quality and resistance to distress) over the life of the pavement, and a structural overlay method which calculates thickness required to prevent structural failure. Flexible overlay design Method 2 of the 1986 AASHTO Guide for the Design of Pavement Structures was selected for structural capacity design. Method 2 uses nondestructive testing (NDT) deflection data input to calculate overlay thickness. A negative value for overlay thickness indicates that sufficient structural capacity is present without adding an overlay. The functional performance approach used Indiana flexible pavement historical data to produce a regression equation relating overlay thickness to traffic, design life oil the overlay, pavement condition at the end of the design life, and estimated subgrade California bearing ratio. Various NDT deflection measurements, climate zone data, and pavement layer thickness variables were included in a variety of empirical analyses, but they were not significant in the analyses. Simultaneous use of the two design methods was recommended to IDOH. If values from both methods are positive, the larger value governs the design. If the structural value is negative, a thickness equal to the functional performance design may be milled and recycled back to the pavement.