Construction of European Base/Subbase

The primary measures of construction acceptance adopted in the U.S. for subsurface layers are thickness and density. In many European countries, however, the specifications frequently include strength measures, in addition to measures such as density and thickness. For example, in Germany and Belgium, plate load tests are conducted in the field, and the strength parameters must meet the requirements. If the strength requirement is not achieved in the field, contractors are required to take additional action (e.g., extra compaction, stabilization) before the next pavement layer is constructed. Similar practice is also found in Austria and Switzerland [Houben 2009, Rens 2016].