Road essentials. Adding geosynthetics to basic roadway design strategies: Fid-Bau Portal

Road essentials. Adding geosynthetics to basic roadway design strategies

Proper drainage cannot be overstressed in road construction and maintenance. Water affects the entire serviceability of a road. Water allowed to remain on top of a gravel or asphalt road weakens the surface and, combined with traffic, causes potholes and cracking. If improperly routed, water causes soil erosion and a breakdown of pavement edges. Subsurface drainage may be the most important factor contributing to the longevity of a pavement section. This can be accomplished through subsurface drainage and separation of the base course from the subgrade using geotextiles. Proper surface drainage can reduce the amount of water from infiltrating the pavement surface. However, the road's subgrade determines the service-life of a road. A stable subgrade can be developed through reinforcement, separation or stabilization. This can be accomplished using low-strength geotextiles, high-strength geotextiles or geogrids. When soil is improperly compacted, future traffic loads or changes in moisture content can cause settling or swelling and failure of the roadway. A road that has a poor base and poor drainage cannot be adequately improved with a top dressing of gravel or new pavement. Roads need regular maintenance to keep them from deteriorating. Maintenance activities include: roadway surfaces: blading and shaping, patching, resurfacing, snow and ice removal; drainage: cleaning and repairing culverts and ditches; roadside: cutting bushes and grass; repair and prevention of roadside erosion; traffic services: sign maintenance; cutting vegetation to maintain visibility.