By: Fred Faridazar and Mauricio Ruiz
How well will your new portland cement concrete (PCC) pavement perform? Will it be prone to cracking? Get a helping hand in determining the early-age behavior of your PCC pavement with the Federal Highway Administration’s (FHWA) free HIPERPAV III software.
HIPERPAV was first released in 1996, followed by an updated version in 2005. The software program allows users to predict early-age concrete pavement behavior based on user-defined inputs for environmental, design and construction conditions. The user inputs variables such as ambient weather conditions, thickness of pavement, mix design, time of placement and type of curing. Mathematical models then calculate the progression of the concrete’s strength gain and developing stresses for the first 72 hours after placement. If the stresses are greater than the strength for any given point of time within the first 72 hours, the concrete has an increased potential for early-age cracking. HIPERPAV alerts the user to this potential for jointed plain concrete pavement (JPCP).
The software was designed for use by state and local highway agencies, contractors, suppliers and members of the academic community. In the new HIPERPAV III, an enhanced moisture transport model has been developed and incorporated into the software. The improved moisture model captures the interaction between pavement design, materials, environmental and construction inputs and provides a more realistic characterization of moisture transport in the slab and its effect on early-age drying shrinkage, warping stresses and strength development in the slab.
New inputs were included in the software to define the experimentally determined hydration curve parameters to improve predictions of degree of hydration and PCC temperature development. A batch mode also was added for analysis of multiple strategies at once, and a comparison module was created that allows users to compare simulation results from multiple strategies and run sensitivity analysis for multiple variables.
An improved interface allows users to opt between a Simple or Advanced Strategy View. The Simple Strategy View is easy to use and more intuitive, while the Advanced Strategy View gives the user an option to enter additional information on each of the input categories to obtain more accurate predictions of early-age behavior. Also included in the software is a feature that allows the user to input calorimetric data for the purpose of characterizing more precise heat evolution.
The HIPERPAV program is already making a difference for states such as Ohio and California, which are using it on their paving projects to evaluate the early-age cracking potential of concrete. The Wisconsin Department of Transportation, meanwhile, uses a customized version of the software that includes unique Wisconsin data inputs.
For more information or to download a free copy of the software and start putting the power of HIPERPAV III to work for you today, visit www.hiperpav.com.
About The Author: Faridazar is a highway research engineer at FHWA’s Turner-Fairbank Highway Research Center in McLean, Va. Ruiz is a program manager at Transtec Group Inc. in Austin, Texas.
