DISCLAIMER. CE990 Graduate Seminar Presentations

Transcription

1 DISCLAIMER The presentation materials shown in this file were prepared by graduate engineering students for educational purposes within the Department of Civil and Geological Engineering at the University of Saskatchewan. The quality and accuracy of the information presented, including supporting design calculations, drawings, cost estimates, and conclusions reached are not necessarily consistent with professional engineering standards even though reasonable efforts have been made to this end. The practice of professional engineering in Canada can only be undertaken by appropriately licensed professional engineers therefore all contents of this presentation, including all data, figures, drawings, findings and cost estimates cannot be used, in whole or in part, for the design and/or construction of any engineering works without an appropriately licensed professional engineer taking professional responsibility for the contents so used. Any use of, or reliance on, the information contained in this file by any third party is at that party s sole risk. Further, any use of the information contained in this file should be cleared with the author, and must provide full acknowledgement to the author. CE990 Graduate Seminar Presentations

2 MECHANISTIC STRUCTURAL ANALYSIS AND DESIGN OF RECYCLED AGGREGATES IN ROAD CONSTRUCTION CASE STUDY: CITY OF SASKATOON Presented by Duane Guenther M.Sc. Candidate, Third Year Department of Civil and Geological Engineering, University of Saskatchewan February, 2012 Supervisor Dr. Curtis Berthelot

3 Highlights Introduction Test Materials Test Locations Material Characteristics Design Cross Sections Design Models Economics Conclusion

4 Introduction Current Design Assumptions Based on AASHTO Designs Thick asphalt structures Highway type traffic Historical Results Good subgrades Easily accessed aggregates

5 Introduction Current Design Assumptions SMHI CBR Nomograph Local Roadway CBR mm HMA 225mm Granular

6 What has changed Subgrade type is changing as City develops Introduction Pre % of city developed on marginal soil types 1990 to % of new development on marginal soil types Projected to % to 70% of new development on marginal soil types

7 Introduction What has changed 95km 95km 80km 40km 40km Aggregate sources are depleting Haul now is from 50 to 100km outside city limits

8 What has changed Introduction Vehicle loading in residential neighborhoods is increasing Bus routes Garbage pickup Public wants more information Openness on how budget decisions are made Emphasis on environmental awareness

9 What is needed Paradigm shift in roadway design Introduction Designing for critical loading Designing for climatic conditions Incorporating various aggregates into design protocols Means of analyzing different construction options and validating reasons for construction decisions

10 Current building practices unsustainable Roads Failing Prematurely Introduction

11 Crushed Concrete Test Materials

12 Crushed Asphalt Test Materials

13 8 Test Locations Test Locations

14 2009 Test Locations Test Locations

15 Test Locations 2010 Test Locations

16 Material Characteristics Evaluated materials using COS standard specification requirements Test for gradation CBR specified for material type Test for fractured faces Relatively open qualities Evaluate existing specifications and determine if additional specifications are needed or changes need to be made to current COS standards.

17 Material Characteristics Three Recycled Asphalt Gradations Tested 19mm RAP (Well Graded) 25mm RAP (Open Graded) 65mm RAP (Open Graded)

18 Material Characteristics Three Recycled Concrete Gradations Tested 19mm PCC (Well Graded) 19mm PCC (Open Graded) 25mm PCC (Open Graded)

19 Mechanistic Material Testing Material Characteristics

20 Design Cross Sections 60mm HMAC 250mm Granular Base (Dry) 250mm Granular Base (Wet) in situ Subgrade (poor) 60mm HMAC 200mm Stabilized in situ Recycled HMAC/Base 300mm Crushed PCC Drainage Rock in situ Subgrade (good) in situ Subgrade (poor)

21 Design Stress Strain Models 3.5 m 60 mm HMAC 250 mm Dry Base 250 mm Wet Base Poor Subgrade 3.5 m 60 mm HMAC 200 mm Stabilized in situ Recycled 300 mm Crushed PCC Rock Good Subgrade Poor Subgrade 3.5 m 60 mm HMAC 250 mm Dry Base 250 mm Wet Base Poor Subgrade 3.5 m 60 mm HMAC 200 mm Stabilized in situ Recycled 300 mm Crushed PCC Rock Good Subgrade Poor Subgrade

22 Design Validation Design Stress Strain Models

23 Economics

24 Conclusion Recycled Concrete and Asphalt products are financially feasible alternative aggregates Existing standards do not adequately characterize recycled material properties Evaluating the mechanistic characteristics of the material shows the recycled materials to have improved characteristics over standard aggregates The test sections validate the design models predicted performance

25 Advisor: Dr. Curtis Berthelot COS Staff PSI Technologies Inc. University of Saskatchewan Acknowledgements

26 Thank You! Presented by Duane Guenther, M.Sc. Candidate February 3, 2011