A Protocol for the establishment and operations of LTPP sections

1. A Protocol for the establishment and operations of LTPP sections Prepared for Gautrans by CSIR, Transportek

2. Background • LTPP programmes developed to support the analysis of pavement performance leading to improved engineering tools for design, construction and management • Current LTPP programmes focus on performance models for PMSs • Needs to be a link to APT for greater confidence in interpreting APT results

3. Background cont.. • In SA financial constraints have prevented LTPP test sections being linked to pavement performance under APT • LTPP sections have been developed on an ad hoc basis or as part of calibration sections • Renewed interest worldwide in linking APT to LTPP

4. Background cont.. • For reliable models and design specs, it is imperative that data collected during LTPP programmes are reliabe and consistent with data collected during APT • Protocol already exists for establishment and operations of HVS test sections • Protocol required for LTPP to provide a consistent approach

5. Structure of Protocol • Linking LTPP to HVS data collection • Management and responsibilities • Site location and establishment Data collection • Reporting criteria

6. Minimum measurement requirements

7. LTTP Staff Organisation Chart Project Director Road Authority/Agency Project Manager In-house or service provider Field Technician Database manager Technician’s Assistant (s)

8. Proposed layout of LTPP sections 200 m – full lane width • HDM calibration sections 500 m long covering entire road width • Detail provided on instrumentation, markings and measurement points

9. Data collection • Monitoring every 6 months in May and October or when failure occurs • Sampling only from panels A, B and C or if failure occurs in other panels • Recommendations on reinstatement of test pits given to ensure impermeability • Monitoring standards given for: • Visual assessment • Transverse profile • Longitudinal profile • Density and M/C • DCP • Environment • Deflection • Permanent Deformation • Traffic

10. Laboratory testing • Essential that material properties at the time of construction (or initiation of section) are fully recorded for comparison over time • As built records may not give sufficient detail • Testing programme initiated at the following intervals: • Pre-construction/rehabilitation • Post construction/rehabilitation • In service (approx half-way through the design life of section) • Rehabilitation/end of service • Details of all recommended tests given in the document

11. Reporting of results • All field monitoring and test data checked by field technician and then PM before sending to the Database Manager • Any lab results sent with field data • 1st level analysis carried out after each monitoring • 2nd level analysis every 2 years to include: • An evaluation of the structural behaviour • The identification of any extraneous effects • The development and refinement of performance prediction models • On HVS/LTPP sections, the relationship between LTPP and HVS performance for similar traffic levels