Overview of paving
Pavements are actually a civil engineering structures used for the purpose of operating wheeled vehicles safely and economically, paved roadways include the carriageways and the shoulders have been constructed for more than a century. Their basic design methods and construction techniques have undergone some changes, but the development in the past decades has provided the strategies for enhancing the overall performance of the paved roadways. Various levels of government, in most of the countries, devote unprecedented time and resources to roadways construction, maintenance and repair. Efforts are very also important that being made to apply newfound technology to old pavement problems.
Commonly a paved road becomes candidate for maintenance when its surface shows significant cracks in pavement surface cause numerous problems such as, including riding discomfort for the users, reduction of safety, infiltration of water and subsequent reduction of bearing capacity of the sub grade, pumping of soil particles through the crack, and progressive degradation of the road structure on the vicinity of the cracks due to stress concentrations.
There are two functions of geosynthetics which can barely help in pavement but before that geosynthetic layer, define as a special geotexile layer that used beneath asphalt overlays, raging in thickness from 25 to 100mm, of asphalt concrete and the Portland cement concrete paved roads, while the geotextile layer is generally speak or combined with asphalt sealant, or tack coat to form a membrane interlayer system which is known as a paving fabric interlayer which also shows the layer arrangement in paved roads with a paving fabric interlayer. 1. Fluid barrier that impregnate with bitumen that is asphalt cement and protecting the underlying layers from degradation due to infiltration of road-surface moisture. 2. A cushion, which is stress-relieving layer for the overlays, retarding and controlling of some common types of cracking including reflective cracking.