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Compaction of asphalt mixtures represents a critical step in the construction process that significantly affects the performance and durability of asphalt pavements. In this research effort; the compaction process of asphalt mixtures was investigated using a combined experimental and computational approach. The primary goal was to understand the main factors responsible for achieving good density and was triggered by the success of a recently proposed Superpave 5 mix design method. First; a two-scale discrete element method (DEM) model was developed to simulate the compaction process of asphalt mixtures. The computational model was anchored by a fluid dynamics-discrete element model; which is capable of capturing the motion of aggregates in the viscous binder. The model was then calibrated and validated by a series of experiments; which included rheological tests of the binder and a compaction test of the mixture. It was concluded that the compaction process was significantly influenced by the rheological properties of the fine aggregate matrix and by the sphericity of the coarse aggregates. Finally; the mechanical properties of two high-density mixtures were determined and compared with mechanical properties of mixtures used for MnROAD 2017 National road Research Alliance (NRRA) test sections. It was found that the properties of high-density mixtures as a group were not significantly different compared to the properties of conventional mixtures.

Crack sealing is an important preventive treatment in the pavement preservation program. To achieve a cost-effective crack seal; it is important to select a proper crack sealing method. While Minnesota usually seals cracks in asphalt pavements; there is no clear consensus on the most appropriate crack sealing method for a specific job. This study focused on developing a guideline so that a cost-effective crack sealing method could be chosen based on pavement type; functional condition; pavement age; and traffic volume etc. This study includes a literature review; online survey; field performance data collection and analysis; and development of a guideline. The effectiveness of the crack seals was determined using a benefit-cost analysis. Two decision trees were developed for choosing the most appropriate crack sealing method. The first; which can be used in MnDOT's pavement management system; needs information such as crack severity; pavement type (new vs overlay); pavement analysis period and design life; traffic level; and crack seal occurrence number. The second decision tree; which is a simplified version of the first and can be used by the preventive maintenance crews and requires less information: crack severity; traffic level; and crack sealing occurrence number.

This chart is part of report 2019-26 "Cost/Benefit Analysis of the Effectiveness of Crack Sealing Techniques," published in 2019

These appendices pertain to report 2019-26, Cost/Benefit Analysis of the Effectiveness of Crack Sealing Techniques. APPENDIX A: AASHTO PROVISIONAL STANDARDS FOR CRACK SEALANT TESTS APPENDIX B: PHYSICAL REQUIREMENTS OF MNDOT SEALANTS (AFTER, MNDOT, 2016) PHYSICAL REQUIREMENTS OF MNDOT 3719 SEALANT APPENDIX C: PRELIMINARY SURVEY - GOOGLE FORM APPENDIX D: SECONDARY SURVEY FORM APPENDIX E: MNDOT DATABASE - RESOURCES APPENDIX F: PROJECT INFORMATION - CRACK SEALING METHODS APPENDIX G: CONSTRUCTION HISTORY OF CRACK SEALING METHODS APPENDIX H: PROJECT INFORMATION: FINAL ROUT-AND-SEAL PROJECTS APPENDIX I: CONSTRUCTION HISTORY OF CRACK SEALING METHODS: FINAL ROUT-AND-SEAL PROJECTS APPENDIX J: SAMPLE WORK-PLAN SHOWING CLEAN-AND-SEAL PROJECT SITES APPENDIX K: PROJECT INFORMATION: FINAL CLEAN-AND-SEAL PROJECTS APPENDIX L: CONSTRUCTION HISTORY OF CRACK SEALING METHODS: FINAL CLEAN-AND-SEAL PROJECTS APPENDIX M: TRAFFIC (AADT) FOR CRACK SEALING PROJECT LOCATIONS APPENDIX N: TRAFFIC (AADT) FOR FINAL ROUT-AND-SEAL SECTIONS APPENDIX O: TRAFFIC (AADT) FOR FINAL CLEAN-AND-SEAL SECTIONS APPENDIX P: SUMMARY OF DATA FOR PERFORMANCE EFFECTIVENESS ANALYSIS: ROUT-AND-SEAL SECTIONS APPENDIX Q: SUMMARY OF DATA FOR PERFORMANCE EFFECTIVENESS ANALYSIS: CLEAN-AND-SEAL SECTIONS APPENDIX R: DATA COLLECTION FORM FOR SEAL PERFORMANCE APPENDIX S: DATA COLLECTION FORM FOR SEAL INSTALLATION APPENDIX T: PERFORMANCE EVALUATION OF NEWLY-INSTALLED CRACK SEALING PROJECTS (PHASE 3) APPENDIX U: PERFORMANCE EVALUATION OF OLD CRACK SEALING PROJECTS (PHASE 4)