Evaluation of New Compaction Control Technology in order to Modification of Soil Compaction Quality Assurance within our Country Road Construction Projects

Level of compaction and its uniformity is an important parameter to specify mechanical quality of road layers. Compaction is an expensive and time consuming procedure therefore without applying decent compaction control tools; the results could be unsuitable and cause premature local and general distresses. Compaction quality control, as is common in Iran, can be based on end-product specifications or combination of method specifications and end-product specifications. In situ test method results have relatively low accuracy on assessing materials properties. Some limitations associated with these test methods are: random quality control of compaction, unreliable results in some of this method due to presence of oversized particles, moisture content dependency in stiffness based methods, measurement depth limitation in some of in situ test methods and lack of lift thickness control. Using several means including controlographe (in order to record daily roller operation like speed control, traveled distance, frequency, vibration), roller performance tables, and test section construction it is possible to have primary control over compaction procedure that can lead to higher uniformity and quality of compaction. By introduction of continuous compaction control (CCC) systems, most of conventional in situ test method limitations were solved. The main goal of this technology is to produce uniformly compacted pavement and high quality products. This method makes it possible to monitor compaction control and construction simultaneously and 100 percent coverage on the compacted area. The objective of this study is to investigate CCC systems and evaluation of conventional in situ compaction verification tests and specifications for compaction control of embankments and pavement layers in order to propose a solution to modify existing situation in Iran.