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

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

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

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

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

Minimum measurement requirements PropertyLTPPHVSDifference VisualsMod TMH 9/HDM calib guide Description of cracks TMH-9 standard with added info on cracks Trans profileStraight edge & wedge/electronic straight edge Laser profilometerFull lane too wide for laser prof Long profileCalibrated profiometer Straight edgeLTPP section too long for straight edge DeflectionRSD, FWDRSDFWD used routinely in Gautrans Perm defMDD Density Dual probe strata gauge M/CGrav m/c used for calibration Pvmnt TempTemp buttons TrafficW-i-MHVS Weather detailsWeather station

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

Proposed layout of LTPP sections A12345B678910C 5 x 15m10 m 5 x 15m Not to scale 200 m – full lane width HDM calibration sections 500 m long covering entire road width Detail provided on instrumentation, markings and measurement points

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

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

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 1 st level analysis carried out after each monitoring 2 nd 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