A series of HIPERPAV workshops have been organized and conducted throughout the United States to demonstrate HIPERPAV and to inform contractors, academia, and state departments of transportation (DOT) of the importance of early-age behavior. These workshops captured the attention of local government agencies, private industry, and educational institutions. This implementation phase has succeeded because of the unified approach taken by the FHWA, Transtec, and the American Concrete Pavement Association. Each party has identified great benefits in the HIPERPAV system and has taken a unique role in its successful implementation.
Leading highway agencies in implementing HIPERPAV include the Wisconsin DOT for which HIPERPAV was recently tailored to meet their local conditions and the Ohio DOT that has developed specifications where the use of HIPERPAV is required to evaluate paving scenarios.
Efforts to Implement HIPERPAV II have and will continue to be conducted. Technical support, training sessions, and additional workshops throughout the States are being provided to demonstrate the new HIPERPAV system to government agencies and the pavement industry in general.
HIPERPAV’s uses to the pavement and construction industries are extensive. HIPERPAV is designed to improve pavement performance and durability through the careful selection of input parameters related to concrete materials, pavement design, pavement construction, and climatic conditions. This synergistic approach to concrete pavement design yields many applications:
- HIPERPAV can be used to predict and prevent uncontrolled cracking in jointed concrete pavements at early ages. The temperature and moisture models contained in HIPERPAV predict the development of the pavement’s concrete strength, as well as the pavement stresses. As long as the stresses are lower than the strength of the concrete, cracks are not likely to occur. If cracking is possible, HIPERPAV allows the user to modify input parameters and to tailor the design and construction to minimize the possibility of crack formation.
- HIPERPAV can be used to determine the optimum joint sawcutting window during construction. When sawcutting joints in concrete pavements, it is important that the joints are not sawcut too early or too late. If joints are cut too early, the strength gained by the concrete may be not enough to support the saw cutting equipment. This will cause structural damage to the pavement. Likewise, raveling along the joint can occur, which can later turn into significant spalling damage. If the joints are cut too late, uncontrolled cracking may occur at any point in the pavement. The joints need to be cut before the tensile stresses in the concrete exceed the concrete strength. This window of opportunity can be determined using HIPERPAV.
- HIPERPAV can assist in assessing the costs and benefits of opening a concrete pavement to traffic. Opening pavements after construction in a prudent and expeditious manner is needed to minimize user costs. Rehabilitation and reconstruction operations on congested streets and highways are a common source of frustration and delays for commuters. HIPERPAV can predict the time when adequate strength has developed in the concrete so that the roadway can be opened to traffic.
- HIPERPAV can quantify the risks of using stabilized bases. Stabilized bases often lead to extremely high friction stresses between the pavement and the subbase. This is a common cause of uncontrollable cracking at early ages. Using HIPERPAV, the stresses generated in the concrete from the interfacial restraint can be evaluated. This allows the pavement design to be modified to prevent the formation of cracks by using bond breakers at the interface.
- HIPERPAV can predict the impact of climatic conditions on pavement performance. A cold front, or paving in desert climates where there are significant temperature drops from day to night, can be evaluated in terms of pavement performance. The damage caused by these sudden climatic changes can be prevented with HIPERPAV, since it can simulate ways to prevent pavement damage. Possible alternatives are to control the temperature of the concrete mix, to select a different time for placement, or to use different curing methods.
- With the incorporation of the CRCP module, many of the benefits in the original HIPERPAV system are now also applicable to this pavement system as well.
- Prediction of JPCP long-term performance will assist the practitioner in optimizing the selection of design and construction factors that minimize long-term performance distress, therefore, promoting high performance concrete paving.
- The incorporation of mix optimization and dowel analysis modules in HIPERPAV will open up a new door to development of a series of early-age concrete products intended to promote better design and construction of concrete pavements. This will improve long-term pavement performance and reduce the costs of pavement rehabilitation in the long term.
Given its wide range of applications, HIPERPAV is currently being used as a tool by planners, designers, and contractors. During the planning stage, HIPERPAV is used to develop quality control specifications for a particular project based on the available materials and climatic conditions of the region in study. Designers use HIPERPAV to optimize their pavement designs based on the best selection of the design variables. This will produce a better end product and guaranteed long-term pavement performance, while maximizing economy. Contractors use HIPERPAV to prevent expensive repairs by predicting potential damage due to unexpected conditions and determine the best set of factors that will prevent damage to the pavement. Finally, the software is used in pavement forensic studies to assess the causes of pavement damage and poor pavement performance.