PaveCool App - The Authoritative Asphalt Cooling & Compaction Calculator
Welcome to pavecool.com - the definitive online resource for the PaveCool app (also known as Pave Cool), the industry-standard asphalt cooling prediction software developed by Minnesota DOT and the University of Minnesota. Download the PaveCool app for Windows, iOS, or Android.
What is PaveCool App?
The PaveCool app (Pave Cool) is government-developed, GPLv3-licensed asphalt cooling prediction software that solves a critical problem in cold-weather paving operations: calculating precisely how long crews have to compact hot-mix asphalt before it cools too much for effective densification.
Using a one-dimensional heat conduction model based on Fourier's Law, PaveCool calculates the cooling rate of freshly-placed asphalt pavement. When hot-mix asphalt (HMA) is delivered at 275-325°F and laid on a road surface, it begins cooling immediately. Compaction must occur while the mix is still hot enough to densify properly—typically above 175°F (80°C). PaveCool calculates exactly how many minutes crews have in this critical "compaction window."
History and Development
PaveCool originated from CTS Project #1994029, titled "An Asphalt Paving Tool for Adverse Conditions," initiated in December 1994 at the University of Minnesota's Department of Civil, Environmental and Geo-Engineering. The research was funded by Minnesota DOT's Office of Research Administration.
Key developers include David Newcomb (Principal Investigator), Vaughan Voller (heat transfer modeling), Bruce Tanquist (lead developer and current maintainer), and David Timm (who later developed MultiCool at Auburn University).
In 2000, the Federal Highway Administration reviewed version 2.0 and helped distribute it to all state DOTs nationwide, establishing PaveCool as a national standard.
Download PaveCool App
The PaveCool app (Pave Cool app) is available for multiple platforms. Download PaveCool for free:
- PaveCool Windows App (Version 3.1) - Full-featured desktop application
- PaveCool iOS App (Version 3.2) - Mobile Pave Cool app for iPhone and iPad
- PaveCool Android App (Version 3.2) - Mobile Pave Cool app for Android devices
- PaveCool Web App - Install as a Progressive Web App (PWA) for offline use
- Source Code - GPLv3 licensed, available from MnDOT
Technical Documentation
PaveCool uses a one-dimensional heat conduction model based on Fourier's Law: ∂T/∂t = α × ∂²T/∂x². The software divides the lift thickness into discrete layers and iteratively solves the heat equation over 2.1 hours with 20-second time steps.
Key factors affecting cooling rate include wind speed (highest impact), lift thickness (high impact), air temperature (medium impact), base temperature (medium impact), delivery temperature (medium impact), and solar radiation (lower impact).
Frequently Asked Questions
What is the cessation temperature for asphalt?
The cessation temperature is the temperature at which asphalt becomes too stiff to compact effectively, typically 175°F (80°C). Rolling below this temperature often results in crushed aggregate rather than increased density.
How does wind affect asphalt paving?
Wind is the single biggest factor in surface heat loss. A wind speed of 10-15 mph can reduce the time available for compaction by up to 50% compared to a calm day.
Can I pave when the ground is frozen?
Paving on frozen ground creates a "heat sink" that rapidly draws thermal energy from the bottom of the mat. While possible with thick lifts (3 inches+), thin lifts on frozen ground will typically cool too fast to compact properly.
How can I extend my compaction window?
Strategies include increasing lift thickness (1.5" to 2" can nearly double the window), tarping loads, adding rollers, scheduling during warmer parts of the day, and using wind screens.
Industry Adoption
PaveCool is endorsed by the Federal Highway Administration and referenced in specifications by Minnesota DOT, Texas DOT, Colorado DOT, Wisconsin DOT, and others. The National Asphalt Pavement Association lists it as a recommended resource, and the Asphalt Institute references it in certification programs.
Open Source License
PaveCool is genuinely open source under GNU General Public License v3 (GPLv3). Full source code is publicly available including pavecool.cpp, pavecool.h, globals.h, UI files, and supporting modules.