Long-Term Plan for Concrete Pavement Research and Technology— The Concrete Pavement Road Map (Second Generation): Volume II, Tracks

TRACK 8. CONCRETE PAVEMENT CONSTRUCTION, RECONSTRUCTION, AND OVERLAYS

TRACK 8 OVERVIEW

For more than 20 years, the concrete pavement industry has confronted facts and perceptions about concrete pavement construction under high-speed construction conditions. While the industry’s record is generally positive, perceptions still determine concrete use in many situations. The traffic growth data presented in chapter 1 in volume I of the CP Road Map show that despite the gains made in the past decade, concrete pavements throughout the country will continue to be in need of rehabilitation under high-speed construction conditions.

While asphalt pavement has traditionally been viewed as the only solution for overlays of existing pavement, tremendous advances have been made over the past decade in the understanding and usage of concrete pavements. Concrete overlays present a solution that facilitates high-speed rehabilitation by eliminating the need to remove the existing pavement prior to constructing a long-life concrete pavement.

The next generation of construction and rehabilitation tools combines the software and hardware required to simulate system design and predict problems that might surface during accelerated construction. High-speed computer simulation can troubleshoot a pavement’s response to environmental changes, as well. However, effective construction management remains critical for meeting the goals and objectives of this track.

Future high-speed construction challenges the industry to move away from slipform paving and identify ways to make precast construction a more viable alternative. Precast modular construction might not only replace ultra high-speed construction, but also improve product quality and extend the paving system.

Research in this track will include the following:

• Planning and simulating high-speed construction and rehabilitation.
  
  
• Precast and modular options for concrete pavements.
  
  
• Fast-track concrete pavement construction and rehabilitation.
  
  
• Evaluation and technology transfer of high-speed construction and rehabilitation products and processes developed through research.

Some high-speed construction issues are also investigated in other research tracks, and those efforts will be coordinated closely with those in this track. For example, tracks 1 and 3 contain many elements required in a high-speed option.

The following introductory material summarizes the goal and objectives for this track and the gaps and challenges for its research program. A table of estimated costs provides the projected cost range for each problem statement, depending on the research priorities and scope determined in implementation. The problem statements, grouped into subtracks, follow.

Track 8 Goal

This track will explore new and existing products and technologies that facilitate high-speed rehabilitation and construction of PCC pavements.

Track 8 Objectives

The track 8 objectives are as follows:

1. Develop planning and simulation tools that allow contractors, designers, and owner-agencies to identify potential problems before construction begins and identify the most efficient processes.
   
   
2. Explore and refine precast and modular pavement technology for new construction, rehabilitation, and maintenance.
   
   
3. Emphasize the benefits and provide guidance for usage of concrete overlays as a high-speed rehabilitation solution.
   
   
4. Refine fast-track construction technologies and techniques and synthesize them into best practice guidelines for contractors, designers, and owner-agencies.
   
   
5. Provide the means for all contractors, designers, and owner-agencies to learn about new high-speed construction and rehabilitation products and technologies.

Track 8 Research Gaps

The track 8 research gaps are as follows:

• Lack of easy-to-use and practical education tools.
  
  
• Insufficient data and methodology for calculating user benefits from high-
  speed construction.
  
  
• Insufficient understanding of ways to control potential long-term durability problems resulting from high-speed construction.
  
  
• Lack of user knowledge.

Track 8 Research Challenges

The track 8 research challenges are as follows:

• Develop easy-to-use and understandable products and portable user-friendly software for contractors, designers, and owner-agencies.
  
  
• Quantify the user costs versus benefits of high-speed rehabilitation and construction products to allow owner-agencies to realize the economic benefit.
  
  
• Assess the long-term durability of various high-speed rehabilitation and construction techniques.
  
  
• Address the perception that concrete is an inherently slow construction process.

Research Track 8 Estimated Costs

Table 43 shows the estimated costs for this research track.

Track 8 Organization: Subtracks and Problem Statements

Track 8 problem statements are grouped into the following five subtracks:

• Subtrack 8-1. Construction, Reconstruction, and Overlay Planning and Simulation.
  
  
• Subtrack 8-2. Precast and Modular Concrete Pavements.
  
  
• Subtrack 8-3. Concrete Overlays.
  
  
• Subtrack 8-4. Fast-Track Concrete Pavements.
  
  
• Subtrack 8-5. Construction, Reconstruction, and Overlay Evaluation and Implementation.

Each subtrack is introduced by a brief summary of the subtrack’s focus and a table listing the titles, estimated costs, products, and benefits of each problem statement in the subtrack. The problem statements follow.

SUBTRACK 8-1. CONSTRUCTION, RECONSTRUCTION, AND OVERLAY PLANNING AND SIMULATION

This subtrack frames new and innovative ways to conduct high-speed construction, reconstruction, and overlays relying on the creative use of simulation tools. Table 44 provides an overview of this subtrack.

Problem Statement 8-1-1. Characterization of Existing Portland Cement Concrete or Hot Mix Asphalt Pavement to Provide an Adequate Rehabilitation Design

• Track: 8. Concrete Pavement Construction, Reconstruction, and Overlays.
  
  
• Subtrack: 8-1. Construction, Reconstruction, and Overlay Planning and Simulation.
  
  
• Approximate duration: 3 years.
  
  
• Estimated cost: $3.5–$4.5 million.

The United States contains a huge infrastructure of existing highway pavements. Every day, designers grapple with ways to develop an adequate design that will reliably carry traffic over the next design period. To accomplish this task, researchers must characterize or evaluate the existing pavement adequately and overcome its inherent deficiencies with a sufficient rehabilitation design. Several end products related to the characterization of existing concrete or asphalt pavement will result from these research tasks. Improved characterization of existing pavements will be the most significant and valuable accomplishment. Improved estimates of remaining pavement life will be useful for selecting alternative rehabilitations. Identifying and providing solutions to overcome several existing poor design and material situations will be extremely valuable. Finally, improving key unbonded concrete overlay design procedures will lead to greater reliability and cost effectiveness.

The tasks include the following:

1. Develop improved procedures for characterizing an existing concrete or asphalt pavement to provide an adequate rehabilitation design.
   
   
2. Develop a procedure to rapidly determine the remaining life of an existing PCC pavement. The procedure should allow a designer to make remaining pavement life determinations by integrating data on current design features, accumulated and future environmental and loading data, data on existing conditions obtained through visual surveys, field and laboratory testing, in-place sensors, and advanced pavement performance modeling techniques. This will help determine the best alternative rehabilitation designs.
   
   
3. Identify the key rehabilitation design issues related to overcoming a poor existing design and materials for rehabilitation.
   
   
4. Develop improved procedures and technology for unbonded concrete overlays.
   
   
5. Determine the effect of the existing PCC slab on unbonded overlay performance.
   
   
6. Identify the interface conditions for various surface preparations and treatments necessary for achieving optimal performance based on field studies of in-place pavements.
   
   
7. Develop guidelines for selecting the separation layer that will be used to design unbonded overlays considering the existing pavement condition, type and design of the overlay, climate, and traffic loadings. Evaluate the effects of interface degradation or improvements over time.

Benefits: Proper characterization of the existing pavement critical to reliable and cost-effective rehabilitation design and rehabilitation design improvements to the pavement design guide.

Products: Improved characterization of existing pavements, improved estimates of remaining life that will be useful for selecting from alternative rehabilitations, identification of solutions for overcoming existing poor design and material situations, and improved support for unbonded concrete overlay design.

Implementation: Good rehabilitation requires good evaluation. The results of this research will be implemented immediately into improved concrete overlay rehabilitation design procedure. This problem statement is linked to problem statement 2-3-2.

Problem Statement 8-1-2. Paving Process Simulations and Constructability Review

• Track: 8. Concrete Pavement Construction, Reconstruction, and Overlays.
  
  
• Subtrack: 8-1. Construction, Reconstruction, and Overlay Planning and Simulation.
  
  
• Approximate duration: 5 years.
  
  
• Estimated cost: $1–$2 million.

Recent projects, such as the 55-h weekend reconstruction of I-10 near Pomona, CA, have demonstrated the viability of rapid pavement reconstruction. This project, and similar projects, have also demonstrated the need for advanced planning and preparation to ensure project success under strict time constraints. Advanced planning will ensure optimal construction staging, equipment utilization, mixing procedures, and hauling processes. Time-motion and production-cost analyses are two examples of analysis techniques that can be used for this type of optimization. A formal constructability review manual will be developed to assist in better planning. Rehabilitation and construction process simulations, which incorporate time-motion and production-cost analyses, will be a powerful tool for optimizing project planning and preparation to ensure the success of time-restrictive pavement construction and rehabilitation. Simulations will allow contractors and transportation agencies to analyze the flow of rehabilitation or new construction projects well in advance of actual construction, allowing researchers to anticipate potential problems that may prevent the time requirements from being met.

The tasks include the following:

1. Identify construction process simulation techniques/models currently available (such as those used in the bridge and building industries).
   
   
2. Identify problems or limitations of current simulation techniques/models based on contractor/agency experience.
   
   
3. Identify existing constructability review techniques and guidelines.
   
   
4. Evaluate the current simulation techniques and constructability review guidelines for their applicability to concrete paving projects.
   
   
5. Identify agency and contractor needs for expedited pavement construction (e.g., typical rehabilitation or construction timeframes required).
   
   
6. Identify constraints for expedited pavement construction (e.g., equipment limitations, concrete mix characteristics, and construction staging).
   
   
7. Develop simulation techniques/models that account for both contractor/agency requirements and constraints, building on the successes of existing simulation models.
   
   
8. Develop a case study that demonstrates the simulation technique/model on an actual construction project.
   
   
9. Refine the simulation techniques/models as needed based on the case study.
   
   
10. Develop a constructability review manual for concrete paving, employing peer review and revision during the development process.

Benefits: New tools that contractors and owner-agencies can use to simulate the paving process before construction, allowing them to identify potential problems and optimize equipment and materials; a constructability review manual for concrete paving that will allow owner-agencies to assess rationally the potential for success of a given construction plan.

Products: Easy-to-use paving process simulation tools (software) and a constructability review manual for concrete paving.

Implementation: This research will result in easy-to-use tools (i.e., software and a constructability review manual) for contractors, designers, and owner-agencies to perform rehabilitation and construction process simulations and reviews.

Problem Statement 8-1-3. Traffic Management Simulations

• Track: 8. Concrete Pavement Construction, Reconstruction, and Overlays.
  
  
• Subtrack: 8-1. Construction, Reconstruction, and Overlay Planning and Simulation.
  
  
• Approximate duration: 4 years.
  
  
• Estimated cost: $500,000–$1 million.

Traffic management is a crucial aspect of any pavement rehabilitation/construction project, but it is particularly important for rapid rehabilitation and construction projects where construction is often conducted under traffic. Rapid rehabilitation/construction work under traffic burdens both the highway agency and contractor to produce a high-quality pavement while minimizing traffic delay and maximizing traffic safety. In some cases, the option of a long-life pavement is ruled out for such projects because of skepticism that it can be built with minimal user delays. Moreover, in certain situations, user costs and delays can outweigh all other considerations for pavement construction, reconstruction, or rehabilitation. In these cases, special steps must be taken to minimize lane closures and reduced traffic access. Proper traffic management better ensures the safety of workers and helps minimize traffic congestion during construction. However, developing a traffic management plan to satisfy both objectives is extremely difficult and often very costly. Generally, traffic management plans are developed for a specific project based on previous experience within a localized region. Thus, for similar project circumstances across the country, significant variance in traffic handling options can and does occur. Many agencies employ less-than-optimal approaches to managing traffic, which result in extra costs, safety concerns, and significant user delays. A solution to this problem would be to develop techniques or models for simulating different traffic management scenarios based on the requirements of individual projects. These techniques/models will allow the contractor or owner-agency to simulate different traffic management strategies well in advance of construction, allowing them to identify problems and select the optimal strategy.

The tasks include the following:

1. Identify traffic management techniques/models currently used by owner-agencies.
   
   
2. Identify problems or limitations of current techniques/models based on contractor/
   agency experience.
   
   
3. Identify agency constraints for traffic management (e.g., typical rehabilitation or construction timeframe, and restrictions on traffic diversion).
   
   
4. Identify viable models for user cost prediction of traffic management and life-cycle cost models for concrete pavements.
   
   
5. Develop simulation techniques/models that account for both contractor/agency requirements and constraints.
   
   
6. Develop a case study that demonstrates the simulation technique/model on an actual construction project.
   
   
7. Refine the simulation techniques/models as needed based on the case study.
   
   
8. Develop agency/contractor interactive alternative models.

Benefits: New tools that contractors, designers, and owner-agencies can use to simulate different traffic management scenarios before construction, allowing them to identify potential problems and select the optimal traffic management scenario.

Products: Easy-to-use traffic management simulation tools (software).

Implementation: This research will result in easy-to-use tools (i.e., software) that contractors, designers, and owner-agencies can use for traffic management simulations.

Problem Statement 8-1-4. Virtual Construction Simulations

• Track: 8. Concrete Pavement Construction, Reconstruction, and Overlays.
  
  
• Subtrack: 8-1. Construction, Reconstruction, and Overlay Planning and Simulation.
  
  
• Approximate duration: 2 years.
  
  
• Estimated cost: $500,000–$1 million.

Recently, a number of industries have been turning to simulation tools to assess potential issues that could arise during the execution of industry processes. A notable example is the aerospace industry, which conducts numerous tests of aircraft and aircraft components using virtual simulations. In these simulations, the components are “assembled” using computers, and the process is monitored at critical points and compared to threshold values. Stresses, for example, are compared to strengths. Time is recorded, and efficiency statistics are derived. This research will explore and synthesize this technology and others like it in the hope of applying the same concepts to the concrete pavement construction process. The virtual simulations will consider both the paving process and traffic management strategies to optimize not only the construction process, but also the total cost, including user costs. The simulations will allow contractors and owner-agencies to perform virtual simulations of a complete concrete pavement construction or rehabilitation project to evaluate overall costs, identify problems, and determine an optimal construction process.

The tasks include the following:

• Identify and evaluate existing virtual simulation models used in different industries.
  
  
• Evaluate aspects of existing virtual simulation models applicable to concrete pavement construction and rehabilitation simulation models.
  
  
• Develop a virtual simulation model that considers both the paving or rehabilitation process and the traffic management strategy.
  
  
• Develop a case study that applies the virtual simulation model to an actual
  construction project.
  
  
• Refine the virtual simulation model as needed based on the case study.

Benefits: New tools that will allow contractors, designers, and owner-agencies to simulate the entire construction process virtually before actual construction, allowing them to identify potential problems.

Products: Construction simulation software that considers both the paving process and
traffic management.

Implementation: This research will result in easy-to-use tools (i.e., software) that contractors, designers, and owner-agencies can use for virtual construction simulations.

SUBTRACK 8-2. PRECAST AND MODULAR CONCRETE PAVEMENTS

This subtrack organizes the entire modular concrete pavement concept so that it can be used for both high-speed and high-durability situations. Table 45 provides an overview of this subtrack.

Problem Statement 8-2-1. Refinement of Precast Post-Tensioned Concrete Pavement Technology

• Track: 8. Concrete Pavement Construction, Reconstruction, and Overlays.
  
  
• Subtrack: 8-2. Precast and Modular Concrete Pavements.
  
  
• Approximate duration: 4 years.
  
  
• Estimated cost: $500,000–$1 million.

Precast concrete offers a durable and lasting solution for rapid construction of PCC pavement. A 1998 feasibility study completed by the Center for Transportation Research at the University of Texas at Austin concluded that precast prestressed concrete pavement is a viable option for large-scale rapid reconstruction of concrete pavements.⁽¹¹⁾ The concept that resulted from the feasibility study incorporates both pretensioning and post-tensioning in the precast panels to reduce the required slab thickness as well as improve the durability of the finished pavement. Subsequent implementation studies resulted in the construction of precast, prestressed pavement demonstration projects in California, Texas, Missouri, Iowa, Delaware, and Virginia. Despite the successes of these demonstration projects, however, refinements to the concept are needed for precast, prestressed concrete to become readily accepted as an expedited construction technique for PCC pavements. These refinements may include modifications to design details, fabrication processes, and construction techniques to make precast prestressed concrete an economical alternative for expedited pavement construction. This research will aim to develop a refined concept that is incorporated easily into current PCC pavement practices and to familiarize owner-agencies with this technology.

The tasks include the following:

1. Evaluate all aspects of previously constructed precast prestressed concrete pavement demonstration projects (i.e., design details, fabrication, construction, performance, and cost).
   
   
2. Refine details and processes so that precast, prestressed pavement can meet the construction timeframe requirements of owner-agencies.
   
   
3. Work with precast concrete and concrete paving industries to make precast concrete pavement an economically viable alternative to other fast-track PCC paving techniques.
   
   
4. Familiarize contractors and owner-agencies with precast prestressed concrete pavement construction technology.
   
   
5. Develop specifications, design standards, and/or best practice guidelines for precast prestressed concrete pavement.
   
   
6. Construct precast prestressed concrete pavement test sections under stringent (e.g., overnight and weekend) time constraints.

Benefits: Best practice guidelines for precast prestressed concrete pavement technology, helping owner-agencies develop design standards and specifications.

Products: Design standards, specifications, and best practice guides for precast prestressed (post-tensioned) concrete pavement.

Implementation: This research will be used to develop design standards, specifications, and best practice guidelines for precast prestressed (post-tensioned) concrete pavement.

Problem Statement 8-2-2. Precast Concrete Pavements for Slab Replacement

• Track: 8. Concrete Pavement Construction, Reconstruction, and Overlays.
  
  
• Subtrack: 8-2. Precast and Modular Concrete Pavements.
  
  
• Approximate duration: 4 years.
  
  
• Estimated cost: $500,000–$1 million.

Precast concrete offers a durable and lasting solution for rapid full-depth slab replacement for PCC pavement. Recent projects in Colorado, Michigan, New York, New Jersey, California, and Virginia have demonstrated the viability of using precast concrete panels for rapid full-depth repairs of PCC pavement. The success of these projects has emphasized the need to make this technology available to all owner-agencies and contractors for rapid repair projects. This research will evaluate the performance of the different construction techniques used on previous projects. Recommendations and specifications then can be developed to help contractors and owner-agencies incorporate precast concrete pavement into common fast-track pavement rehabilitation practices. The recommendations and specifications should cover all aspects of precast pavement construction including precast panel fabrication, construction staging, existing pavement removal, base preparation, and panel installation.

The tasks include the following:

1. Evaluate performance of existing precast concrete pavement rehabilitation projects.
   
   
2. Develop specifications and design standards for precast pavement.
   
   
3. Make precast concrete an economically viable alternative to current fast-track rehabilitation techniques.
   
   
4. Familiarize contractors and owner-agencies with precast pavement technology and construction practices.

Benefits: Best-practice guidelines for using precast panels in full-depth slab replacement. 

Products: Design standards, specifications, and best practice guidelines for using precast concrete in full-depth slab replacement.

Implementation: This research will result in design standards, specifications, and best practice guidelines for using precast concrete in full-depth slab replacements.

Problem Statement 8-2-3. Lightweight Precast Concrete Pavements

• Track: 8. Concrete Pavement Construction, Reconstruction, and Overlays.
  
  
• Subtrack: 8-2. Precast and Modular Concrete Pavements.
  
  
• Approximate duration: 3 years.
  
  
• Estimated cost: $250,000–$500,000.

Recently, several projects throughout the United States have demonstrated the viability of using precast concrete panels for large-scale pavement construction and full-depth pavement rehabilitation. One key cost component of precast concrete panels is transportation. Precast panels used for current projects can weigh in excess of 25 short tons, sometimes requiring special permits to transport. One way to improve the efficiency of precast concrete pavement transportation is to reduce the weight of the precast panels. Reducing panel weight by as little as 20 percent may permit the shipment of more panels on each truck or eliminate the need for a special permit. Technology, such as lightweight aggregates and hollow-core panels, has been used successfully by the precast industry for buildings and bridge decks, but have yet to be applied to precast pavement panels. This research will incorporate these technologies into precast concrete pavement practices.

The tasks include the following:

1. Identify potential weight-reducing technologies for precast concrete pavement panels.
   
   
2. Evaluate the benefits versus costs of incorporating weight-reducing technology into precast concrete pavement practice including evaluation of durability issues associated with weight-reducing technologies.
   
   
3. Recommend weight-reducing techniques for precast concrete pavement practice.

Benefits: Exploration of possible weight-reducing technologies for precast concrete pavement.

Projects: Recommendations for weight-reducing technologies for precast concrete pavement.

Implementation: This research will result in recommendations for weight-reducing technologies for precast concrete pavement.

Problem Statement 8-2-4. Precast Joints for Joint Replacement

• Track: 8. Concrete Pavement Construction, Reconstruction, and Overlays.
  
  
• Subtrack: 8-2. Precast and Modular Concrete Pavements.
  
  
• Approximate duration: 4 years.
  
  
• Estimated cost: $500,000–$1 million.

Recent projects in Colorado, Michigan, New York, New Jersey, and Virginia have demonstrated the viability of using precast concrete panels for joint replacement. Often, heavily faulted joints, which have lost subbase support due to pumping, cannot simply be ground smooth or retrofitted with dowel bars. In these cases, it is necessary to replace the joint completely to restore subbase support and load transfer between faulted slabs. Unfortunately, these joint replacements often are required on heavily trafficked pavements that can only be closed to traffic overnight or over a weekend. Precast concrete offers a durable and long-lasting solution that permits construction overnight or over a weekend. This research will examine the performance of different precast concrete joint replacement techniques and familiarize contractors and owner-agencies with these techniques so they can be incorporated into common practice.

The tasks include the following:

1. Document construction practices and performance of current precast concrete joint replacement techniques.
   
   
2. Develop design standards, specifications, and/or best practice guidelines for owner-agencies to incorporate into current practice.
   
   
3. Familiarize contractors and owner-agencies with precast concrete joint replacement technology.

Benefits: Best-practice guidelines for using precast concrete panels for joint replacement.

Products: Design standards, specifications, and best-practice guidelines for using precast panels for joint replacements.

Implementation: This work will be coordinated closely with that in track 6. This research will result in precast concrete joint replacement specifications, design standards, and best practice recommendations.

Problem Statement 8-2-5. Precast Quiet Pavement Surfaces

• Track: 8. Concrete Pavement Construction, Reconstruction, and Overlays.
  
  
• Subtrack: 8-2. Precast and Modular Concrete Pavements.
  
  
• Approximate duration: 5 years.
  
  
• Estimated cost: $500,000–$1 million.

Pavement noise, or the noise generated by tires on a pavement surface, is an important consideration in PCC pavement construction, particularly in urban areas. Different surface textures are being examined constantly for their effectiveness in reducing pavement noise. Unfortunately, many of the most promising surface textures are difficult to construct properly in the field. However, precast concrete pavement panels are cast in a controlled environment, affording a great deal of flexibility with surface texture. New surface texture technologies, such as extruded channels, are currently being evaluated abroad. While such textures may be difficult to construct in the field, they can be easy to incorporate into precast pavement panels. This research will identify new surface textures that show promise for reducing pavement noise and evaluate the feasibility of incorporating them into precast pavement panels.

The tasks include the following:

1. Identify surface texture techniques that have been shown to reduce pavement noise.
   
   
2. Evaluate the feasibility of incorporating these surface textures into precast pavement panels versus conventional (slipform or fixed-form) PCC construction.
   
   
3. Evaluate the benefits versus costs of using precast panels with noise-reducing surface texture for PCC pavement construction.
   
   
4. Develop case studies or pilot projects that incorporate noise-reducing surface textures into precast pavement and evaluate their effectiveness.

Benefits: Exploration of noise-reducing techniques that may not be viable for conventional concrete pavements but that can be incorporated into precast concrete pavements.

Products: Recommendations for noise-reducing techniques for precast concrete pavement surfaces.

Implementation: This research will be used to evaluate the viability of precast pavement with specialized, noise-reducing surface textures versus conventional pavement construction with conventional surface textures.

SUBTRACK 8-3. CONCRETE OVERLAYS

This subtrack focuses on concrete overlays as a high-speed and durable solution for pavement rehabilitation. Table 46 provides an overview of this subtrack.

Problem Statement 8-3-1. Improvement of Two-Dimensional and/or Three-Dimensional Structural Models for Jointed Plain Concrete Pavement and Continuously Reinforced Concrete Pavement Used for Reconstruction and Overlays

• Track: 8. Concrete Pavement Construction, Reconstruction, and Overlays.
  
  
• Subtrack: 8-3. Concrete Overlays.
  
  
• Approximate duration: 6 years.
  
  
• Estimated cost: $5–$6 million.

The MEPDG uses the ISLAB2000^® FEM to structurally model JPCP and CRCP that are built new and used as overlays.⁽¹⁾ The FEM calculates critical stresses and deflections from traffic and climate factors and then uses them to predict damage and distress. While this is a good state-of-the-art FEM for design use, models must be developed that will more accurately calculate stresses in all types of concrete pavements and rehabilitation situations.

The tasks include the following:

1. Include capability to consider both loading and thermal gradients in a layered system with discontinuities (joints and cracks).
   
   
2. Model all types of concrete pavements and overlays over all types of existing pavement conditions (multiple layers and discontinuities).
   
   
3. Model the effect of all types of bases/subbases and widths on structural responses at joints and other locations.
   
   
4. Model the effect of horizontal restraint (friction) on joint and crack openings and structural responses.
   
   
5. Model the effect of separation layers on structural responses.
   
   
6. Improve modeling of subgrade support for new and rehabilitation designs.
   
   
7. Test and validate the FEMs using the benchmark problems developed under this design track.

Benefits: Better characterization of design features, interlayer relationships, and material properties and FEMs incorporated into new versions of the pavement design guide.

Products: Improved 2D and 3D FEM that provides significantly improved computation of stresses and deflections for JPCP and CRCP used in reconstruction and as overlays and pavement performance prediction models that more accurately predict pavement distress and life for incorporation into a new version of the pavement design guide.

Implementation: The FEM will be incorporated into design procedure as soon as completed. It also will be used for parameter and sensitivity studies. This problem statement is linked to problem statement 2-1-2.

Problem Statement 8-3-2. Structural Models for Special New Types of Concrete Pavements and Overlays

• Track: 8. Concrete Pavement Construction, Reconstruction, and Overlays.
  
  
• Subtrack: 8-3. Concrete Overlays.
  
  
• Approximate duration: 6 years.
  
  
• Estimated cost: $1–$2 million.

Continually seeking improved and more cost-effective concrete pavement designs is important. New and innovative alternative designs have been constructed, and others will be proposed over time. As an initial step, it is important to have a capable structural model that accurately calculates stress and deformation of these pavement types. This research will expand or modify the latest FEM to model different types of concrete pavements structurally.

Task: Expand or modify FEMs to model the following concrete pavement types and their layered systems beneath the slabs:

• Precast JCP.
  
  
• Structurally reinforced concrete pavement.
  
  
• Concrete overlays.
  
  
• Other new and innovative types identified.

Benefits: The ability to consider new and innovative concrete pavement structures for more cost-effective conventional or special design applications.

Products: FEM models that accurately predict structural responses for the slab and supporting layers in selected structural systems.

Implementation: The effects of new and innovative designs cannot be established without structural models. These structural models will be implemented into design procedures as soon as the feasibility of special designs is established. This problem statement is linked to problem statement 2-1-5.

Problem Statement 8-3-3. Improvements to Concrete Overlay Design Procedures

• Track: 8. Concrete Pavement Construction, Reconstruction, and Overlays.
  
  
• Subtrack: 8-3. Concrete Overlays.
  
  
• Approximate duration: 5 years.
  
  
• Estimated cost: $4–$4.5 million.

Reliably designing all types of concrete overlays is essential to highway agencies. However, existing procedures lack a number of capabilities. This research will address a variety of those needs for both bonded and separated concrete overlay designs and for both existing concrete and asphalt pavements.

The tasks include the following:

1. Develop guidelines and procedures for designing concrete overlays and widening existing narrow slabs.
   
   
2. Develop reliable design procedures for ultra-thin slabs placed on existing concrete or asphalt layers. Improved evaluation techniques of the existing pavement and improved bonding and design procedures are needed.
   
   
3. Develop improved layering and jointing models to consider unbonded concrete overlays and the underlying layers.
   
   
4. Develop technology to estimate the required design inputs for considering the design and condition of the existing concrete pavement.
   
   
5. Develop improved bonding techniques for bonding concrete layers over existing concrete slabs.

Benefits: Concrete overlays of difficult existing pavements; ultra-thin slab design including improved concrete-to-asphalt bonding procedures, improved layering modeling for unbonded concrete overlays, characterization of underlying concrete slab design and condition for unbonded overlays, and improved bonding between thin concrete overlay and existing concrete slabs.

Products: Improved guidelines and design procedures for several types of concrete overlays including concrete overlays of difficult existing pavements, ultra-thin slab design that includes improved concrete-to-asphalt bonding procedures, improved layering modeling for unbonded concrete overlays, characterization of underlying concrete slab design and condition for unbonded overlays, and improved bonding between thin concrete overlay and existing concrete slabs.

Implementation: Concrete overlays must be more cost effective to compete with alternatives. The results of this research will be implemented immediately into concrete pavement design procedures. This problem statement is linked to problem statement 2-3-3.

Problem Statement 8-3-4. Design, Construct, and Evaluate Concrete Overlays

• Track: 8. Concrete Pavement Construction, Reconstruction, and Overlays.
  
  
• Subtrack: 8-3. Concrete Overlays.
  
  
• Approximate duration: 7 years.
  
  
• Estimated cost: $3–$5 million.

Concrete overlays are discussed throughout the CP Road Map, especially in the problem statements addressing the use of asphalt bases throughout track 1. This problem statement will develop approaches to long-life pavements that consider concrete overlay construction principles during initial construction and over the analysis period. The research in this problem statement addresses JCPs or CRCPs over an asphalt base or subbase with a cement/epoxy-type or porous concrete surface. For all surface types, the surface is renewable, and the concrete slab is expected to require little maintenance or rehabilitation for 30 to 50 years or more.

The tasks include the following:

1. Determine operational strategies that could accommodate concrete overlay construction principles.
   
   
2. Determine ways to incorporate issues concerning asphalt bases with PCC surface courses (e.g., changes in temperature gradients and thickness and stiffness of the layers) into structural design.
   
   
3. Develop the initial functional and performance requirements of the top surface course to meet economic, safety, and environmental concerns, as well as traffic loadings and volumes.
   
   
4. Determine the surface course material requirements for meeting two or three different life expectancy predictions before replacement is required.
   
   
5. Identify any the adjustments required to properly integrate specific materials issues with the structural values developed in task 2.
   
   
6. Determine the bonding requirements between surface and slab necessary for meeting the desired performance criteria.
   
   
7. Consider issues of delaminating, reflection cracking, clogging and stability, and the impact of contained moisture in the structure.
   
   
8. Study the effects of the concrete surface layer on the structural design of the slab.
   
   
9. Determine the construction issues unique to these concrete overlay sections, addressing each interlayer and develop guide specifications for each significant type of concrete overlay.
   
   
10. Build, monitor, and evaluate the various test sections.

Benefits: An exceptionally strong, long-life pavement with concrete overlay, combining the strengths of a solid concrete foundation with a renewable surface designed around functional requirements.

Products: Promising concrete overlay types with appropriate design features, surface characteristics, foundations, materials, construction, QC/QA, and preservation treatments.

Implementation: The research in this problem statement will be coordinated with work in track 9. This research also will be integrated with Strategic Highway Research Program 2 (SHRP 2) Renewal Project R21, Composite Pavement Systems, as it pertains to concrete overlays.(12) Results from the design, construction, and materials aspects of this research will be useful immediately to States, while performance data will be useful over time. This research also may be addressed in other tracks (e.g., tracks 2, 4, and 6). This problem statement is linked to problem statement 9-3-4.

Problem Statement 8-3-5. Flexible Cementitious Overlay Materials

• Track: 8. Concrete Pavement Construction, Reconstruction, and Overlays.
  
  
• Subtrack: 8-3. Concrete Overlays.
  
  
• Approximate duration: Not available.
  
  
• Estimated cost: $500,000–$1 million.

The majority of HMA pavements will ultimately fail due to rutting. Increased axle loads, higher tire pressures, and increasing traffic volume contribute to this problem. Today, more than 90 percent of roads are being overloaded. Developing a cementitious overlay material that can be used as a strengthening and wearing course on flexible pavements, even when applied in thin layers, would be extremely useful. Ductility of the material is obtained through controlled microcracking and fiber reinforcement. A major project is currently underway in the European Union to look at porous polymer concretes. Several different compositions such as this could be used, resulting in the selection of a few types to be used for full-scale testing as overlays on appropriate highways. A similar project could be conducted in the United States that builds on the information and results from the European Union project. Design criteria and draft specifications for the use of the new material will be a part of the project results.

The tasks include the following:

1. Identify required properties for thin overlays.
   
   
2. Identify existing materials used for thin cementitious overlays.
   
   
3. Modify existing materials or develop new materials for thin overlays, if necessary.
   
   
4. Develop field trials or accelerated load testing of overlay materials.
   
   
5. Develop design criteria, specifications, and construction procedures for use of cementitious overlay materials.

Benefits: New and more durable overlay material that is less susceptible to rutting and shoving than asphalt and can be placed in thin, flexible layers.

Products: Specifications, design criteria, and construction procedures for flexible cementitious overlays.

Implementation: This project will result in draft specifications, design criteria, and construction procedures for flexible cementitious overlays.

SUBTRACK 8-4. FAST-TRACK CONCRETE PAVEMENTS

This subtrack examines issues related to the next generation of fast-track paving and fast-track concrete pavement preservation techniques including the removal of existing pavement and the use of materials that facilitate fast-track paving. Table 47 provides an overview of this subtrack.

Problem Statement 8-4-1. Synthesis of Practice for Accelerated (Fast-Track) Paving

• Track: 8. Concrete Pavement Construction, Reconstruction, and Overlays.
  
  
• Subtrack: 8-4. Fast-Track Concrete Pavements.
  
  
• Approximate duration: 2 years.
  
  
• Estimated cost: $250,000–$500,000.

In the mid-1980s, FHWA initiated a unique program that brought together individuals from the concrete pavement industry and State highway agencies. The goal of this program was to assess the state of the practice of fast-track (accelerated) concrete paving practices. Since then, numerous concrete paving projects have been constructed using the practices recommended under this effort. In addition, there have been significant advancements in technology, including new materials and construction techniques. For example, new fast-setting hydraulic cements are currently being employed by some agencies to place full-depth concrete pavements over a weekend. This project will document the current state of the practice of accelerated PCC paving technology. Literature searches, surveys of transportation agencies, and interviews with contractors and owner-agencies will help establish the current state of the practice and will document pros, cons, successes, and failures associated with different accelerated paving technologies.

The tasks include the following:

1. Perform a literature search to identify different accelerated paving technologies
   currently available.
   
   
2. Survey transportation agencies in the United States, Canada, and abroad to determine which technologies have been used previously or are currently being used.
   
   
3. Conduct site visits and interviews with owner-agencies to determine pros, cons, successes, and failures of different technologies.
   
   
4. Synthesize results of the literature search, surveys, and interviews into a current state of the practice.

Benefits: One-stop shopping for different accelerated paving techniques.

Products: Synthesis of the current state of the practice for accelerated paving techniques.

Implementation: This research will produce a synthesis of the current state of the practice for accelerated paving techniques.

Problem Statement 8-4-2. High-Speed In Situ Portland Cement Concrete Pavement Breakup, Removal, and Processing

• Track: 8. Concrete Pavement Construction, Reconstruction, and Overlays.
  
  
• Subtrack: 8-4. Fast-Track Concrete Pavements.
  
  
• Approximate duration: 4 years.
  
  
• Estimated cost: $2–$5 million.

With the current aging infrastructure, many concrete pavements require complete replacement rather than minor rehabilitation. Unfortunately, many of these pavements are located in urban areas that permit only short construction windows for removing and replacing the pavement. Removing the existing pavement can be the most time-consuming aspect of this process. Research should investigate the high-speed breakup, removal, and processing of the old pavement material. Ideally, a one-pass operation would break up the pavement, remove it, and crush it into manageably sized material that can then be reused as base material or concrete aggregate. Breaking up and removing old material should not damage the underlying base material or compromise its integrity. Nonimpact methods, such as lasers, should be investigated as possible techniques for breaking up the old concrete. Breakup and processing also should consider concrete pavements with and without asphalt overlays and determine how to separate the two materials.

The tasks include the following:

1. Identify techniques for breaking up existing concrete pavements with or without asphalt overlays including such new nonimpact technologies as lasers.
   
   
2. Identify techniques for removing and processing the material in situ, including techniques for separating asphalt overlay material from PCC material.
   
   
3. Work with industry representatives and contractors to develop new techniques and equipment for high-speed breaking up, removing, and processing old pavements.
   
   
4. Work with owner-agencies to develop pilot studies that use new breakup and removal processes.

Benefits: Equipment that will permit old concrete pavement to be broken up, removed, and processed in place, allowing the concrete material to be recycled into base material or new concrete and significantly reducing or even eliminating waste material.

Products: Equipment for high-speed one-pass in situ breaking up, removing, and processing PCC pavement.

Implementation: This work will result in new equipment for high-speed breakup, removal, and processing of concrete pavement with or without asphalt overlays. This problem statement is linked to problem statement 5-5-1.

Problem Statement 8-4-3. Recycled Concrete Processing/Improvement

• Track: 8. Concrete Pavement Construction, Reconstruction, and Overlays.
  
  
• Subtrack: 8-4. Fast-Track Concrete Pavements.
  
  
• Approximate duration: 4 years.
  
  
• Estimated cost: $1–$2 million.

Reconstructing concrete pavements produces large stockpiles of old concrete material that can be reused in some form for new construction. Several studies have examined sophisticated methods to separate concrete into components that can be used as aggregates and cement precursors. One method heats concrete to between 1,202 and 1,292 °F in an electrical furnace. Another promising technology called Franka-Stein treats concrete in a powerful electric arc using electrodynamic fragmentation, which separates the electrically weak material boundaries prevalent in concrete. In addition to producing clean aggregate, the Franka-Stein process separates cementitious material that can replace natural raw material in cement production. Research is needed to investigate these recycling methods further to determine their cost effectiveness, considering the energy consumption of the separation process.

The tasks include the following:

1. Identify existing processes for separating recycled concrete, including Franka-Stein and others.
   
   
2. Evaluate the effectiveness of the separation processes and the suitability of the resulting material for reuse in new concrete pavement.
   
   
3. Evaluate the cost versus benefit of different recycling processes, considering the energy consumption of the separation process.
   
   
4. Work with contractors and industry representatives to develop new equipment or modify and adapt existing equipment for rapid recycling of concrete pavement.

Benefits: Equipment that will separate crushed concrete properly into materials that can be used for new concrete, minimizing or eliminating waste from reconstructed concrete pavements.

Products: Equipment and recommendations for separating crushed concrete into usable materials.

Implementation: This work will result in equipment for recycling and processing concrete pavement and recommendations for using recycled materials in new concrete. This problem statement is linked to problem statements 5-5-2 and 12-4-6.

Problem Statement 8-4-4. High-Speed In Situ One-Pass Full Concrete Pavement Reconstruction

• Track: 8. Concrete Pavement Construction, Reconstruction, and Overlays.
  
  
• Subtrack: 8-4. Fast-Track Concrete Pavements.
  
  
• Approximate duration: 2 years.
  
  
• Estimated cost: $2–$5 million.

For major reconstruction efforts, traffic control barrels are positioned to alter traffic flow around the work site for weeks or months, straining public travel through the area. Therefore, agencies often delay necessary highway reconstruction or choose less disruptive repairs to avoid traffic interruptions. These decisions eventually strain the State’s pavement network since the majority of the network has a short expected life. In addition, material is removed and hauled offsite during reconstruction, which is a labor-intensive process that often increases the cost and extends the length of reconstruction projects. However, improved equipment capable of removing, recycling, mixing, and placing concrete pavement using a single continuous operation would ease reconstruction.

The process would require a marriage of mobile crushing and screening with a mixer and slipform paver. This research will conceptualize and build efficient and effective methods and/or processes that will permit recycling, mixing, and placing of existing concrete pavement using a single continuous operation.

A recent initiative in Europe advanced the linear quarry. Materials generated by the reclamation of the existing pavement structure would be reprocessed into the new structure along the same alignment. While this concept has been limited to HMA pavements, this research will explore the same concept for concrete pavements. The feasibility of crushing, collecting, sizing, batching, and placing concrete pavements within the right of way should be studied. If the feasibility study returns positive results, additional provisions should be made to test this concept in the field.

The tasks include the following:

1. Identify existing linear quarry technology for in situ material processing and recycling.
   
   
2. Identify existing equipment for in situ PCC materials removal and processing.
   
   
3. Determine the viability of using reprocessed concrete materials for new pavement.
   
   
4. Complete a feasibility study that incorporates breaking up, removing, crushing, sizing, batching, and placing new concrete in a single operation within the right-of-way.
   
   
5. Conceptualize and develop high-speed one-pass in situ reconstruction equipment.

Benefits: Equipment that permits one-pass concrete pavement reconstruction, including breaking up, removing, and processing the old pavement, and placing the new pavement using recycled materials from the old pavement, as well as expedited pavement reconstruction with no waste generated.

Products: New equipment for one-pass concrete pavement reconstruction.

Implementation: This work will assess the feasibility of high-speed one-pass in situ reconstruction equipment and possibly develop such equipment. This problem statement is linked to problem statement 5-5-3.

Problem Statement 8-4-5. Accelerated Paving Techniques

• Track: 8. Concrete Pavement Construction, Reconstruction, and Overlays.
  
  
• Subtrack: 8-4. Fast-Track Concrete Pavements.
  
  
• Approximate duration: 4 years.
  
  
• Estimated cost: $500,000–$1 million.

A significant number of high-early strength concrete mixes have been developed and evaluated in recent years. However, some questions remain regarding the economics and long-term durability of these mixes. Many current high-early strength mixes use exotic cements and other admixtures that have not been proven for long-term durability and can be very costly. Also, these mixes generally do not account for factors such as climatic conditions during construction, curing techniques, and pavement characteristics and thus cannot be adjusted for varying conditions. This research will evaluate current high-early strength mixes and the performance of existing pavements constructed with these mixes. The research will identify the most cost-effective nonproprietary materials and mixes for durable and fast-setting concrete suitable for paving operations. Mixes that are developed will be adjustable based on the pavement characteristics, climatic conditions, and curing techniques available. Guidelines or software should be provided with the mix design that will recommend adjustments to the mix based on climatic conditions during construction. Additionally, maturity/strength gain characteristics for new mixes will be identified and incorporated into the recommendations so that maturity techniques can be used to monitor strength gain during construction.

The tasks include the following:

1. Identify current high-early strength concrete mixes used for accelerated paving.
   
   
2. Evaluate the benefits versus costs of existing mixes including an analysis of
   pavement performance.
   
   
3. Develop new accelerated paving mixes consisting of economical nonproprietary materials.
   
   
4. Analyze maturity characteristics of the new paving mixes for inclusion in the guidelines.
   
   
5. Develop guidelines and/or software for using these new mixes, including recommendations for adjustment based on climatic conditions, pavement characteristics, and curing techniques.
   
   
6. Conduct pilot studies or field trials using the mix design and guidelines developed from
   the study.

Benefits: Development of more economical, nonproprietary, and fast-track paving mixes and guidelines for use.

Products: Possible new mix design recommendations for accelerated paving mixes and guidelines for use, including maturity methods.

Implementation: This research will result in new economical mix designs for accelerated paving and guidelines for using these mixes including maturity.

Problem Statement 8-4-6. Accelerated Hydration Methods

• Track: 8. Concrete Pavement Construction, Reconstruction, and Overlays.
  
  
• Subtrack: 8-4. Fast-Track Concrete Pavements.
  
  
• Approximate duration: 4 years.
  
  
• Estimated cost: $500,000–$1 million.

Hydration of the cementitious materials within a concrete mixture leads to strength development. Strength, in turn, drives a number of critical decisions during concrete pavement construction, including sawcutting and time to opening for traffic. A number of techniques have been advanced that could allow the hydration process to accelerate. Since an increase in mixture temperature is known to accelerate hydration, most of these techniques include heating the concrete slab. Both microwave heating and inductive heating are possible methods, with the latter involving adding metallic fibers to the concrete mixture.

The tasks include the following:

1. Identify technically feasible techniques for heating a concrete pavement in the field.
   
   
2. Evaluate various techniques in the laboratory, assessing their ability to accelerate hydration and monitoring potentially adverse phenomena, such as moisture loss and differential heating.
   
   
3. Identify a technique that demonstrates the greatest potential for the field and apply it to a large-scale operation.

Benefits: More rapid achievement of target strength values (e.g., opening), which, in turn, can shorten the duration of a project.

Products: New techniques for accelerating the hydration process in PCC.

Implementation: This research will result in a technique for accelerating the hydration process that may shorten the time it takes to construct concrete pavements.

Problem Statement 8-4-7. Accelerated Concrete Pavement Restoration Techniques

• Track: 8. Concrete Pavement Construction, Reconstruction, and Overlays.
  
  
• Subtrack: 8-4. Fast-Track Concrete Pavements.
  
  
• Approximate duration: 5 years.
  
  
• Estimated cost: $500,000–$1 million.

Rehabilitation of high-volume rigid pavements requires techniques that minimize disruption to traffic. Usually this restricts construction to nighttime. However, many techniques that have been developed and proven effective for CPR have not been evaluated fully as they pertain to accelerated construction. Research is needed to develop guidelines to help select strategies for rehabilitating high-volume rigid pavements that consider constraints such as lane closures and construction windows. Repair of UTW is one such technique that needs to be investigated, as there are no established guidelines for UTW repair under short time constraints for lane closures. Likewise, partial-depth repair of PCC pavement has shown promise, but guidelines have not been developed for this technique. Full-depth repair of CRCP is another CPR technique that requires guidelines for materials and construction practices. Additionally, environmental effects of CPR techniques must be addressed. Slurry from the diamond grinding process, for example, is considered by some State regulatory agencies to be an environmental hazard that could contaminate groundwater supply. While many States do not regard the slurry as hazardous, the concrete pavement industry needs to examine ways to contain and dispose of the slurry in response to certain State regulatory agencies’ decisions. In general, all aspects of accelerated CPR techniques need to be fully documented including materials, construction practices, and environmental effects.

The tasks include the following:

1. Identify common CPR techniques currently used by owner-agencies.
   
   
2. Conduct surveys and interviews of contractors and transportation agencies to determine the current state of the practice for different CPR techniques and successes and failures for different techniques.
   
   
3. Develop best practice guidelines for each of these techniques based on the surveys and interviews.
   
   
4. Develop a decision matrix for agencies to use in determining applicable CPR techniques, with consideration for accelerated construction.
   
   
5. Evaluate new CPR techniques as they are developed.

Benefits: Best practice guidelines for accelerated CPR techniques.

Products: Best practice guidelines for accelerated CPR techniques.

Implementation: This research will result in best-practice guidelines for common CPR techniques. This problem statement is linked to problem statement 7-2-4.

SUBTRACK 8-5. CONSTRUCTION, RECONSTRUCTION, AND OVERLAY EVALUATION AND IMPLEMENTATION

This subtrack provides the implementation structure for new high-speed construction, reconstruction, and overlay products and procedures. Table 48 provides an overview of this subtrack.

Problem Statement 8-5-1. Workshops on Fast-Track Concrete Paving

• Track: 8. Concrete Pavement Construction, Reconstruction, and Overlays.
  
  
• Subtrack: 8-5. Construction, Reconstruction, and Overlay Evaluation and Implementation.
  
  
• Approximate duration: 8 years.
  
  
• Estimated cost: $1–$2 million.

Proven materials and technologies are currently available for fast-track concrete paving. Unfortunately, many transportation agencies are slow to adopt new techniques due to unfamiliarity with these new technologies and a lack of resources to research them. Workshops provide an ideal environment for agencies to become familiar with and receive training in new technologies. Workshops on fast-track concrete paving should cover the spectrum of proven technologies currently available, including high-early strength concrete mixes, maturity methods for strength monitoring, early-age analysis software (HIPERPAV^®), and others. In addition, other fast-track rehabilitation techniques, such as precast pavement technology and UTW, should also be presented.

The tasks include the following:

1. Compile pertinent information on existing fast-track concrete paving technologies, including case studies and the experience of various transportation agencies.
   
   
2. Present fast-track concrete paving techniques and case studies as well as best practices to audiences of contractors, industry representatives, and transportation agencies.
   
   
3. Develop an interactive or NHI course on fast-track paving.

Benefits: Technology transfer through workshops that are a minor investment (if any) for owner-agencies.

Products: Workshops on fast-track concrete paving at various locations throughout the United States.

Implementation: This project will result in numerous workshops on fast-track concrete paving at various venues throughout the country.

Problem Statement 8-5-2. Workshops on Precast and Modular Concrete Pavement Solutions

• Track: 8. Concrete Pavement Construction, Reconstruction, and Overlays.
  
  
• Subtrack: 8-5. Construction, Reconstruction, and Overlay Evaluation and Implementation.
  
  
• Approximate duration: 8 years.
  
  
• Estimated cost: $1–$2 million.

In recent years, several projects have demonstrated different applications for precast concrete pavement. They have included prestressed precast concrete pavement, jointed reinforced precast concrete pavement, precast concrete for slab replacement, and precast concrete for joint replacement. Each of these projects has successfully demonstrated the various techniques for precast and modular solutions for pavements. However, transportation agencies are often slow to adopt new techniques because they are unfamiliar with these new technologies and lack resources for researching them. Workshops will provide an ideal environment for agencies to become familiar with and receive training in current precast pavement technologies.

The tasks include the following:

1. Compile pertinent information on existing precast concrete pavement technologies, including information on all recently completed projects.
   
   
2. Present the different precast concrete paving applications, addressing the advantages
   and disadvantages of each technique to contractors, industry representatives, and transportation agencies.

Benefits: Technology transfer through workshops at minimal or no cost to owner-agencies.

Products: Workshops on precast concrete paving techniques at various locations throughout the United States.

Implementation: This project will result in numerous workshops on precast concrete paving techniques at various venues throughout the country.

Problem Statement 8-5-3. Workshops on Rehabilitation and Construction Simulation and Modeling

• Track: 8. Concrete Pavement Construction, Reconstruction, and Overlays.
  
  
• Subtrack: 8-5. Construction, Reconstruction, and Overlay Evaluation and Implementation.
  
  
• Approximate duration: 5 years.
  
  
• Estimated cost: $500,000–$1 million.

Simulation and modeling are powerful tools for optimizing pavement construction and rehabilitation projects. Simulations allow contractors, designers, and owner-agencies to model construction operations in advance to ensure the most efficient use of equipment and materials. This allows contractors and owner-agencies to anticipate potential problems before construction begins. Simulations also allow designers and/or owner-agencies to analyze traffic management strategies to identify the most efficient strategy and minimize user impact. However, transportation agencies are often slow to adopt new techniques because they are unfamiliar with new technologies and lack resources for researching them. Workshops will provide an ideal environment for agencies to become familiar with and receive training in current simulation and modeling techniques.

The tasks include the following:

1. Identify construction and traffic management simulation techniques. Also, identify case studies that have used the construction and traffic management simulation techniques.
   
   
2. Present the different construction and traffic management simulation tools and case studies, if available, to contractors, designers, and owner-agencies.

Benefits: Technology transfer through workshops at minimal or no cost to owner-agencies.

Products: Workshops on construction and traffic management simulation techniques at various locations throughout the United States.

Implementation: This project will result in numerous workshops on construction and traffic management simulation techniques at various venues throughout the country.

Problem Statement 8-5-4. Web-Based Training for Implementation of Rehabilitation and Construction Research

• Track: 8. Concrete Pavement Construction, Reconstruction, and Overlays.
  
  
• Subtrack: 8-5. Construction, Reconstruction, and Overlay Evaluation and Implementation.
  
  
• Approximate duration: 7 years.
  
  
• Estimated cost: $500,000–$1 million.

Every year, many new products and technologies are developed and made available for implementation. However, many transportation agencies are slow to adopt new products and technology because they are unfamiliar with these new technologies and lack resources to research them. Although workshops provide an opportunity for contractors and owner-agencies to learn about these new products and technologies, many agencies cannot afford to send employees to workshops or may be restricted from traveling to workshops outside their home States. Fortunately, Web-based training allows contractors, designers, and owner-agencies to explore new products and technologies from any computer with Internet access. On-demand Web-based training can take advantage of options such as video streaming for visual demonstrations of new products and technologies.

The tasks include the following:

1. Compile information on products and technologies ready for implementation, including thorough descriptions, photos, and video.
   
   
2. Develop Web-based training modules for each new product or technology.
   
   
3. Create a Web site for accessing the training modules and maintain the Web site with updates for new products or refinements to existing products.

Benefits: Technology transfer available to anyone with computer and Internet access.

Products: Web-based training modules and a continuously maintained Web site for new products and technologies.

Implementation: This project will result in Web-based training modules for new research products and technologies.