Long-Term Pavement Performance (LTPP) Seasonal Monitoring program (SMP) instrumentation was installed in pavement sections at the Ohio SHRP Test Road. The pavements are monitored for the seasonal variations of moisture, temperature and frost penetration. Data from the instrumentation is subjected to quality checks and prepared for uploading to the FHWA Information Management System (IMS). Findings from the testing are to be incorporated into future pavement design procedures.
Monitoring of the environmental instrumentation installed under select pavement sections constructed by the Ohio Department of Transportation (ODOT) in 1995 on US 23 in Delaware County, Ohio was continued. The measurements made consisted of soil moisture, temperature and frost depth profiles.
Seasonal Monitoring Program (SMP) instrumentation was installed in five sections at the Ohio Test Pavement in Delaware County, Ohio using Strategic Highway Research Program (SHRP) protocols developed for the Long-Term Pavement Performance (LTPP) group to the Federal Highway Administration (FHWA). The SMP instrumentation monitors pavements for temperature and pavement bases and subgrade soils for variations in moisture, temperature, and frost penetration. Time Domain Reflectometry (TDR) instrumentation was installed onsite in two sections for monitoring the moisture. Thermal conductivity sensors (TCS) were installed in four sections to measure soil moisture suction. Laboratory soil-water characteristic tests were conducted on remolded subgrade soil.--The TDR volumetric moisture contents typically varied by 10% to 15% from the driest to the wettest periods, but sometimes the variations were larger. The lower water contents occurred during the late winter/early spring months and the higher contents occurred during the late summer/early fall months. This reflects the climatic conditions that occurred. Some of the TDR moisture contents exceeded 40%, wich is greater than the soil porosity and therefore not possible. An equation for TDR volumetric water content developed for the FHWA yields lower water contents. Most of the thermal conductivity sensors are no longer within calibration. Data from sensors in calibration indicate very low matric suctions, which is consistent with high water contents. Soil-water characteristic relationships were obtained for the subgrade soil using trizxial and pressure plate apparatus. The relationships from the two tests are comparable. The soil exhibits some hysteresis when comparing drying and wetting curves.
Highway agencies across the nation are moving towards implementation of the new AASHTO Mechanistic-Empirical Pavement Design Guide (MEPDG) for pavement design. The benefits of implementing the MEPDG for routine use in Ohio includes (1) achieving more cost effective and reliable pavement designs, (2) lower initial and life cycle costs to the agency, and (3) reduced highway user impact due to lane closures for maintenance and rehabilitation of pavements. Implementation of the MEPDG is a process that requires time and agency resources (staffing, training, testing facilities including equipment, and so on). A key requirement is validating the MEPDG's nationally calibrated pavement distress and smoothness prediction models when applied under Ohio conditions and performing local calibration if needed. Feasibility of using the MEPDG's national models in Ohio was investigated under this study using data from a limited number of LTPP projects located in Ohio. Results based on limited data showed inadequate goodness of fit and significant bias in a number of the MEPDG new HMA pavement and JPCP performance prediction models. Limited recalibration of these models showed promising results indicating that a full-scale recalibration effort using a more extensive database assembled from projects located throughout the state is feasible.
Only book world-wide addressing this topic. The principal output of the European co-operative Action on "Water Movements in Road Pavements & Embankments". Provides unique guidance on assessing water condition and its affects on road performance. Provides unique guidance on assessing and ameliorating contaminant movement in pavement groundwater. Written by leading experts in Europe.
