Long-Term Pavement Performance Ancillary Information Management System (AIMS) Reference Guide

RESOURCE DOCUMENTS AND TOOLS

LTPP created a comprehensive set of documents that explain how the data were collected, processed, and stored. The most complete source of these documents is contained in the electronic reference library distributed as part of the LTPP SDR. Some of the resource documents in the reference library include the following:

• Data collection guides.

• Test protocols and procedures.

• Descriptions of field and laboratory test equipment.

• Test section construction reports.

• Monitoring equipment installation reports.

• Experiment design.

• Test section recruitment guidelines.

• Equipment comparison reports.

• Directives.

• Data user guides.

The reference library also contains the following user tools:

• LTPP Table Navigator: A computer program that presents metadata on the structure and contents of PPDB. This includes the table schema, data dictionary, and codes list.

• LTAS Navigator: A computer program that presents metadata on the structure and contents of LTAS. This includes the table schema, data dictionary, and codes list.

• ESALCalc: A computer program that allows the user to compute 18-kip (80-kN) equivalent single-axle loads (ESALs) based on the 1993 American Association of State Highway and Transportation Officials (AASHTO) Guide for Design of Pavement Structures methodology.⁽⁵⁾ An internal database contains computed ESALs from LTPP test sections with traffic monitoring data, or a user can change the input assumptions and perform their own computations.

• FWD forward calculation spreadsheets: These spreadsheets contain a forward calculation technique for estimating layer moduli from FWD deflection measurements developed under a LTPP data analysis contract.

• Rigid pavement design spreadsheet: This spreadsheet automated updates to the 1998 supplement to the AASHTO Guide for Design of Pavement Structures for rigid pavements.⁽⁶⁾

Some of the resource documents, analysis reports, and other tools developed by the LTPP program are available at https://www.fhwa.dot.gov/research/tfhrc/programs/infrastructure/pavements/ltpp/.