BS EN 12697-25:2016 – TC:2020 Edition
$217.84
Tracked Changes. Bituminous mixtures. Test methods – Cyclic compression test
| Published By | Publication Date | Number of Pages |
| BSI | 2020 | 95 |
This European Standard specifies three test methods (A1, A2 and B) for determining the resistance of bituminous mixtures to permanent deformation by cyclic compression tests with confinement. The tests make it possible to rank various mixtures or to check on the acceptability of a given mixture. They do not allow making a quantitative prediction of rutting in the field to be made. Test methods A1 and A2 describe methods for determining the creep characteristics of bituminous mixtures by means of a uniaxial cyclic compression test with some confinement present. In this test a cylindrical test specimen is subjected to a cyclic axial stress. Method A2 is preferred for mastic asphalt and Method A1 for other asphalt mixtures. To achieve a certain confinement, the diameter of the loading platen is taken smaller than that of the test specimen. In test method A1, the test specimen is loaded by block-pulses whereas in method A2 haversine loading with rest time is applied. Test method B describes the method for determining the creep characteristics of bituminous mixtures by means of the triaxial cyclic compression test. In this test a cylindrical test specimen is subjected to a defined confining stress and a cyclic axial stress. This test is most often used for the purpose of evaluation and development of new types of mixtures. This European Standard applies to test specimens prepared in the laboratory or cored from the road. The maximum size of the aggregates is 32 mm. NOTE 1 Confinement of the test specimen is necessary to simulate realistic rutting behaviour, especially for gap-graded mixtures with a large stone fraction. NOTE 2 For the purpose of Type Testing, the test conditions are given in EN 13108-20.
PDF Catalog
| PDF Pages | PDF Title |
|---|---|
| 59 | Contents Page |
| 61 | European foreword |
| 65 | 1 Scope 2 Normative references |
| 66 | 3 Terms and definitions Figure 1 — Example of creep curve |
| 67 | 4 Principle 5 Equipment 5.1 Control and loading system 5.2 Displacement transducers 5.3 Data registration equipment 5.4 Thermostatic chamber |
| 68 | 5.5 Measuring instruments and accessories needed 6 Test specimen preparation 6.1 Number of test specimen 6.2 Test specimen compaction 6.3 Preparation of mastic asphalt test specimen 6.3.1 Accessories for test specimen preparation |
| 69 | 6.3.2 Procedure for moulded test specimen 6.3.3 Procedure for cored test specimen 6.4 Preparation of test specimen surfaces 6.5 Determination of bulk density 6.6 Drying of the test specimen 6.7 Dimensions |
| 70 | 7 Test method A — Uniaxial cyclic compression test with confinement 7.1 Principle 7.2 Test method A1 – block pulse loading 7.2.1 Upper loading plate Figure 2 — Lower edge of the platen 7.2.2 Loading pulse |
| 71 | Figure 3 — Test apparatus Figure 4 — Stress and strain curve for rectangular pulse loading |
| 72 | Figure 5 — Loading curve for block pulse loading 7.3 Test method A2 – Haversine pulse loading 7.3.1 Upper loading plate |
| 73 | Figure 6 — Upper loading platen for test method A2 7.3.2 Loading pulse |
| 74 | Figure 7 — Loading curve for haversine pulse loading 7.4 Test specimen 7.5 Conditioning 7.5.1 Storing conditions |
| 75 | 7.5.2 Cleaning and drying of test specimens 7.5.3 Reduction of friction to loading platens 7.5.4 Temperature conditioning 7.6 Test procedure 7.6.1 Test temperature 7.6.2 Positioning of test specimen in test device 7.6.3 Testing of test specimen 7.6.3.1 Loading conditions (Method A1) |
| 76 | 7.6.3.2 Loading conditions (Method A2) 7.6.4 Measurement of permanent deformation 7.6.5 End of loading 7.7 Calculation and expression of results 7.7.1 Permanent deformation 7.7.1.1 Cumulative permanent deformation |
| 77 | 7.7.1.2 Cumulative axial strain 7.7.2 Creep rate and creep modulus |
| 78 | 7.8 Test report 7.8.1 General 7.8.2 Information on the test specimens 7.8.3 Information on test conditions 7.8.4 Test results |
| 79 | 7.9 Precision 8 Test method B — Triaxial cyclic compression test 8.1 Principle |
| 80 | Figure 8 — Representation of the pressures exerted on the test specimen in case of haversinusoidal cyclic loading with and without rest periods |
| 81 | Figure 9 — Representation of the pressures exerted on the test specimen in case of block-pulse cyclic loading 8.2 Apparatus and test system 8.2.1 General |
| 83 | Figure 10 — Schematic representation of a triaxial cyclic compression test device with pressure cell Figure 11 — Schematic representation of a triaxial cyclic compression test device with pressure ring |
| 84 | Figure 12 — Schematic representation of a triaxial cyclic compression test device making use of a partial vacuum as confining pressure 8.2.2 Loading platens 8.2.3 Control system 8.2.4 Load cell 8.2.5 Height measurements 8.2.6 Temperature conditioning |
| 85 | 8.3 Test specimen preparation 8.3.1 Dimensions 8.3.2 Handling 8.4 Conditioning 8.4.1 Storing conditions 8.4.2 Cleaning and drying |
| 86 | 8.4.3 Reduction of friction to loading platens 8.4.4 Temperature conditioning 8.5 Test procedure 8.5.1 Number of tests 8.5.2 Test temperature 8.5.3 Positioning of test specimen in test device 8.5.4 Testing of test specimen |
| 87 | 8.5.5 Loading conditions 8.5.6 Measurements of permanent deformation |
| 88 | 8.6 Calculation and expression of results 8.6.1 Cumulative strain 8.6.2 Creep curve 8.6.2.1 General 8.6.2.2 Method 1: Determination of the creep rate, |
| 89 | 8.6.2.3 Method 2: Determination of the parameters and 8.6.2.4 Creep curve without stage 2 8.7 Test report 8.7.1 General |
| 90 | 8.7.2 Information on the test specimens 8.7.3 Information on the test conditions 8.7.4 Test results 8.8 Precision |
| 92 | Annex A (informative) Procedure for correction of test results obtained from test specimen of varied age |
