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LTPPBind Online
LTPPBind Online is a web-based tool to help highway agencies select the asphalt binder Performance Grade (PG) for a particular site based on the AASHTO M320-10 standard. Algorithms for high and low temperature are the same as LTPPBind 3.0/3.1 release. LTPPBind Online allows use of MERRA climatic data, LTPP climatic data, or user data for asphalt binder grade calculations. For further details, please see the LTPPBind Online Product Brief.
Disclaimer: LTPPBind Online provides a tool for highway agencies to investigate asphalt binder Performance Grade (PG) ratings in accordance with AASHTO M320-10 and AASHTO M332-14 standards. Climate input options include MERRA-2, LTPP sites, or user defined data. The newest update to LTPPBind performed in September 2018 includes a change to the degree-day over 10 degree C computation that uses the maximum air temperature for each day, and restricts this computation for weather data from the months of April to September of each year. LTPP has determined that this is the most appropriate computation method that the empirical models implemented in LTPPBind 3.1 used for high temperature PG binder grades. LTPPBind Online computes performance grades at 50% and 98% reliability levels. Base HT PG is the high-temperature PG before applying any traffic or depth adjustment. The base HT PG is used only to estimate the traffic adjustment or “bumping grade.” Base HT PG can be assumed from local experience or design guides among the four options available (52, 58, 64 and 70). After running the LTPPBind, the assumed value can be compared with the “Performance Grade Temperature at 50% Reliability” in the Performance Grade Table of LTPPBind. The initial assumption needs to be changed only in the case that the difference between those values is one or more PG grades. This option gives the opportunity to see how the PG HT is impacted by the traffic adjustment. Support for all LTPPBind changes are available through the LTPP Customer Services Support Center. More information on updates to the current version of LTPPBind are available, including links to download desktop versions of the software. A summary of the changes made to the LTPPBind desktop software, LTPPBind documentation, or the LTPPBind Online tool since 2016 is available in a related technical note. Instructions on using this tool are available in the LTPPBind Online User guide (HRT-17-010). For further information regarding the LTPPBind Online tool, please refer to the Tools tab in FAQs. MERRA data used by LTPP reflects the most recent NASA data set which changed in 2016. Projects saved prior to July 2016 and reopened after that date will typically see a change in data values and grid IDs. More information can be found in the MERRA Data Comparison Memorandum. |
