The National Academies Press

Currently Skimming:

Pages 35-50

The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.

From page 35... ... 35 Selection of Performance-Based Test Methods Laboratory test data were analyzed to identify the tests appropriate for identifying RAP and RCP materials intended for use as unbound pavement layers, singularly or in combination with other materials. An adequate test method is expected to measure parameters that influence performance and should be capable of differentiating between sources, types, and blends of recycled aggregate. Read the entire page →
From page 36... ... 36 tested gradation, and material tested. The test yielded different results for different conditions, although similar results were obtained for materials containing limestone and gravel. Read the entire page →
From page 37... ... 37 type, tested gradation, and material for tests conducted on unsaturated and saturated samples (OGDL samples were tested under unsaturated conditions only) Read the entire page →
From page 38... ... 38 Material Tested Dielectric Constant Value Rating RAP-GV-LA 2.0 Acceptable RAP-LS-MS 2.1 Acceptable 50/50 RAP-LS-MS 3.2 Acceptable RAP-GR-CO 3.3 Acceptable RAP-GR-CO 100%OGDL re-blend 3.4 Acceptable 50/50 RAP-GV-LA 3.6 Acceptable 50/50 RAP-GR-CO 3.7 Acceptable RAP-GR-CO 50/50 OGDL re-blend 3.9 Acceptable Virgin OGDL Blend 8.0 Acceptable RCP-GR-SC 50/50 OGDL re-blend 9.5 Acceptable Virgin DGBL Blend#1 9.6 Acceptable 50/50 RCP-GR-SC 10.0 Acceptable RCP-GR-SC 100%OGDL re-blend 10.4 Marginal Virgin DGBL Blend#2 10.6 Marginal RCP-GR-SC 12.1 Marginal 50/50 RCP-GV-LA 13.5 Marginal RCP-GV-LA 14.3 Marginal RCP-LS-IL 16.3 50/50 RCP-LS-IL 21.6 Unacceptable Unacceptable Null Hypothesis, Ho p - Value Remarks MeanRAP = MeanVirgin 0.009 (< 5%) Test method differentiated between RAP and virgin aggregate. Read the entire page →
From page 39... ... 39 0 20 40 60 80 100 120 140 0 50 100 Recycled material content, percent M ax im um d ev ia to r s tre ss , p si RAP-GR-CO (DGBL#2) RAP-GR-CO Reblend (OGDL) Read the entire page →
From page 40... ... 40 The slopes of the deviator stress versus axial strain curve obtained during the load and unload cycles in the repeated load triaxial testing could provide an indication of the performance potential of recycled materials. Figure 5.14 shows typical load/unload curves for RCP and RAP materials. Read the entire page →
From page 41... ... 41 120 130 140 150 160 170 180 190 0 50 100 Recycled material content, percent M ax im um D ev ia to r S tre ss , p si RCP-GR-SC (DGBL) Read the entire page →
From page 42... ... 42 0 20 40 60 80 100 120 140 RCP-GV-LA Virgin OGDL Virgin #2 Virgin #1 RCP-GV-LA (50) Read the entire page →
From page 43... ... 43 0 20 40 60 80 100 120 140 160 180 Virgin #1 RCP-GV-LA RCP-LS-IL Virgin OGDL Virgin #2 RCP-GV-LA (50) Read the entire page →
From page 44... ... 44 0 20 40 60 80 100 120 140 160 180 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0 Axial Strain (%) Read the entire page →
From page 45... ... 45 0 10 20 30 40 50 60 70 Virgin DGBL Blend#1 Virgin DGBL Blend#2 Virgin DGBL Blend RCP-GV-LA 50/50 RAP-GR-CO 50/50 RAP-LS-MS RAP-LS-MS RAP-GR-CO OGDL reblend 50/50 RAP-GV-LA 50/50 RAP-GR-CO OGDL reblend RAP-GR-CO RAP-GV-LA 50/50 RCP-GR-SC OGDL reblend 50/50 RCP-GR-SC 50/50 RCP-LS-IL 50/50 RCP-GV-LA RCP-LS-IL 50/50 RCP-GR-SC OGDL reblend RCP-GR-SC Stiffness, Resilient Modulus (ksi) Figure 5.16. Read the entire page →
From page 46... ... 46 • The Micro-Deval test for toughness, • Resilient modulus for stiffness, • Static triaxial and repeated load at OMC and saturated for shear strength, and • Tube suction test for frost susceptibility. Selection of Recycled Materials for Intended Use Recycled materials can be selected for use in a particular traffic and climatic condition. Read the entire page →
From page 47... ... 47 0 2 4 6 8 10 12 14 16 18 20 50/50 RCP-LS-IL Virgin DGBL Blend#1 RAP-GV-LA 50/50 RCP-GV-LA Virgin OGDL Blend 50/50 RCP-GR-SC RCP-GR-SC 50/50 RAP-GR-CO 50/50 RCP-GV-LA 50/50 RAP-LS-MS RAP-LS-MS RAP-GR-CO RCP-LS-IL RCP-GV-LA Percent Material Loss 4 Significance Level 3 2 and less Figure 5.18. Performance potential based on toughness (Micro-Deval) Read the entire page →
From page 48... ... 48 Selection Based on Repeated Load Triaxial Test Failure deviator stress for repeated load triaxial tests conducted at OMC, shown in Figure 5.21, indicate that virgin aggregates are appropriate for use in high traffic conditions (significance level 4) Read the entire page →
From page 50... ... 50 0 10 20 30 40 50 60 70 RCP-GR-SC 50/50 RCP-GR-SC OGDL reblend 50/50 RCP-GR-SC OGDL reblend 50/50 RCP-GR-SC RAP-GV-LA 50/50 RCP-LS-IL RAP-GR-CO RCP-LS-IL 50/50 RAP-GR-CO OGDL reblend 50/50 RCP-GV-LA RAP-GR-CO OGDL reblend 50/50 RAP-GV-LA 50/50 RAP-GR-CO RAP-LS-MS RCP-GV-LA 50/50 RAP-LS-MS Virgin DGBL Blend#2 Virgin OGDL Blend Virgin DGBL Blend#1 Resilient Modulus (stiffness) at 100 psi Bulk Stress, ksi Significance Level 2 4 31* Read the entire page →

From page 35...

... 35 Selection of Performance-Based Test Methods Laboratory test data were analyzed to identify the tests appropriate for identifying RAP and RCP materials intended for use as unbound pavement layers, singularly or in combination with other materials. An adequate test method is expected to measure parameters that influence performance and should be capable of differentiating between sources, types, and blends of recycled aggregate.