# Construction of Geosynthetic-Reinforced Pavements and Evaluation of Their Impacts
## 5 Conclusions  
In general, this paper develops the procedures and techniques to perform a full-scale field study regarding the geosynthetics-reinforced pavement in Southern Ontario, Canada. This paper describes the installation practices of the geogrid composite installed on the subgrade and a fibreglass geogrid installed in the asphalt binder course. More measures and caution should be taken during the installation of fibreglass geogrid within the asphalt to ensure the bonding of the fibreglass geogrid with the asphalt. This full-scale study also introduces instrumentations for long-term monitoring in Canada. The calibration and installation of the sensors were presented, including temperature strings, moisture probes, pressure cells, and asphalt strain gauges. The results collected during construction were analysed and some field tests were performed to show the impacts of geosynthetics, as listed below:  
* The readings taken from pressure cells on the subgrade show that the fibreglass geogrid in the binder course can diminish the mechanical disturbances vertically from the construction of the binder course and surface course by distributing the load. The geogrid composite can offer little reinforcement of the entire structure during the construction with a similar pressure reading as observed in the control section. * The horizontal strain in the first lift of the binder course caused by construction activities of asphalt placement can be significantly reduced by the fibreglass geogrid installed between the two lifts of the binder course in the transverse direction, with some reduction in the longitudinal direction. The geogrid composite section shows similar horizontal strain values in the binder course during construction with the control section. * Geogrid composite on the subgrade shows improved drainage capability and produces a distinct water potential profile within the pavement structure. The drainage, filtration, and inhibition of upward migration of moisture and fine particles were observed in the geogrid composite section with drier conditions in different depths of the pavements. This indicates an improved performance of the pavements undergoing freeze-thaw cycles and can be verified with future fieldwork at the site. * From the temperature monitoring, the geogrid composite shows indirect insulation capability due to the drainage effect provided by the geotextile, which may decrease the potential for severe freeze-thaw damage. This observation will have to be verified using the long-term monitoring of the pavement sections. * The results of LWD testing indicate the reinforcement of the fibreglass geogrid with the highest stiffness measurements after the asphalt placement. Future fieldwork can be used to determine the long-term benefits of the geosynthetic. * Data collected during two weeks after construction verified that all instrumentations were functioning as expected. A longer monitoring process would be beneficial to evaluate the pavement performance to reduce the prevalence of outliers and spikes in the sensor measurements. Furthermore, further field investigations are recommended to study the long-term behaviour of geosynthetic-reinforced pavements. Non-destructive pavement evaluation techniques can be used to evaluate the permanent deformation under the traffic loading, and the fatigue damage caused by the repetitive loading. Based on the moisture and temperature results, long-term monitoring will also be beneficial to evaluate the performance of the pavement sections after they experience freeze-thaw cycles to investigate the ability of geosynthetic composites to mitigate freeze-thaw. * With certain financial and technical constraints, which limited the ability to employ a larger number of sensors to provide duplication, it is recommended to verify the mechanical responses obtained from the strain gauges and pressure cells by applying certain traffic loading on the pavements; it can also help monitor the performance of in-service pavements.