This contribution describes a project that is part of a larger, long term Dutch program (NL-LAB) that aims to establish the predictive capacity of the current European functional tests for Dutch asphalt concrete mixtures. In this NL-LAB program the functional characteristics, resistance to permanent deformation (EN12697-25) and fatigue (EN 12679-24), stiffness (EN 12697-26) and moisture sensitivity (EN 12697-12 and EN 12697-23), are determined in the process of construction projects. They are determined on specimens that are (I) mixed and compacted in the lab, (II) mixed in the plant and compacted in the lab and (III) mixed in the plant and compacted in the road. These tests will eventually provide insight in the effect of mixing and compaction on the functional characteristics. The project described in this contribution focusses on two of the tests for functional characteristics, indirect tensile strength (ITS)) and the triaxial cyclic compression test (TCCT) for two different AC mixes. The properties found for the specimens from all three stages of preparation are analysed using the formalistic expressions from the Design Guide level II for the estimation of performance indicators. Specifically, this project aimed to see if these relations remain valid for the CEN tests, especially for mixes with high RAP content. In the Netherlands 50% RAP is standard and mixes with up to 80% RAP are commonly used. It was found that the Design Guide expressions fit the CEN test data for these RAC containing mixes quite well, especially for the ITS. Currently another two constructions projects are being sampled and the results from those specimens will be used to validate and improve the relations.
Combining the american and european mix design approaches: utilization of NCHRP performance indicators for analysis of CEN-test results
SANGIORGI, CESARE;LANTIERI, CLAUDIO
2014
Abstract
This contribution describes a project that is part of a larger, long term Dutch program (NL-LAB) that aims to establish the predictive capacity of the current European functional tests for Dutch asphalt concrete mixtures. In this NL-LAB program the functional characteristics, resistance to permanent deformation (EN12697-25) and fatigue (EN 12679-24), stiffness (EN 12697-26) and moisture sensitivity (EN 12697-12 and EN 12697-23), are determined in the process of construction projects. They are determined on specimens that are (I) mixed and compacted in the lab, (II) mixed in the plant and compacted in the lab and (III) mixed in the plant and compacted in the road. These tests will eventually provide insight in the effect of mixing and compaction on the functional characteristics. The project described in this contribution focusses on two of the tests for functional characteristics, indirect tensile strength (ITS)) and the triaxial cyclic compression test (TCCT) for two different AC mixes. The properties found for the specimens from all three stages of preparation are analysed using the formalistic expressions from the Design Guide level II for the estimation of performance indicators. Specifically, this project aimed to see if these relations remain valid for the CEN tests, especially for mixes with high RAP content. In the Netherlands 50% RAP is standard and mixes with up to 80% RAP are commonly used. It was found that the Design Guide expressions fit the CEN test data for these RAC containing mixes quite well, especially for the ITS. Currently another two constructions projects are being sampled and the results from those specimens will be used to validate and improve the relations.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
