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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 last update to LTPPBind occurred in July 2024. A complete listing of modifications made since 2016 is included in the FAQs on this site under Tools – LTPPBind. Instructions on using this tool are available in the LTPPBind Online User guide (HRT-17-010). 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 which summarizes most of the changes in the 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. Recent investigations indicate that the range of years of MERRA data used can impact the suggested PG range. The on-line tool now allows the user to select the range of input years. Contact LTPP Customer Services Support Center for additional background information on the rationale for making this capability available. 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. LTPPBind Online computes performance grades at 50% and 98% reliability levels. |
