Rubberized Hot Mix Asphalt

Transcription

1 Rubberized Hot Mix Asphalt Performance Modeling of Rubberized Hot Mix Asphalt for California Local Agencies California Department of Resources Recycling and Recovery May 15, 2014 Contractor's Report Produced Under Contract By: Andrew Montague, Marissa Garcia, DingXin Cheng, PhD. R. Gary Hicks, PhD., and Lerose Lane, P.E. California Pavement Preservation Center CSU, Chico

2 S T A T E O F C A L I F O R N I A Edmund G Brown Jr. Governor Matt Rodriguez Secretary, California Environmental Protection Agency Department of Resources Recycling and Recovery Caroll Mortensen Director Department of Resources Recycling and Recovery Public Affairs Office 1001 I Street (MS 22-B) P.O. Box 4025 Sacramento, CA RECYCLE (California only) or (916) Publication # DRRR-XXXX-XXX [OPA editor will provide this] To conserve resources and reduce waste, CalRecycle reports are produced in electronic format only. If printing copies of this document, please consider use of recycled paper containing 100 percent postconsumer fiber and, where possible, please print images on both sides of the paper. Copyright 2014 by the California Department of Resources Recycling and Recovery (CalRecycle). All rights reserved. This publication, or parts thereof, may not be reproduced in any form without permission. Prepared as part of contract number DRR [11065]. The California Department of Resources Recycling and Recovery (CalRecycle) does not discriminate on the basis of disability in access to its programs. CalRecycle publications are available in accessible formats upon request by calling the Public Affairs Office at (916) Persons with hearing impairments can reach CalRecycle through the California Relay Service, Disclaimer: This report was produced under contract by the California Pavement Preservation Center. The statements and conclusions contained in this report are those of the contractor and not necessarily those of the Department of Resources Recycling and Recovery (CalRecycle), its employees, or the State of California and should not be cited or quoted as official Department policy or direction. The state makes no warranty, expressed or implied, and assumes no liability for the information contained in the succeeding text. Any mention of commercial products or processes shall not be construed as an endorsement of such products or processes.

3 Table of Contents List of Figures... iii List of Tables... iii Acknowledgments... iv Executive Summary... v Introduction... 1 Background... 1 Purpose of Report... 1 Organization of the Report... 2 Methodology... 3 San Francisco Bay Area... 4 Central Valley... 4 Southern California... 5 Data Mining of Resources... 6 CalRecycle Public Grant List... 6 MTC StreetSaver Data... 6 City and County of Sacramento Southern California Pavement Projects Data Analysis and Performance Models San Francisco Bay Area Central Valley Southern California Summary of Performance Models Conclusions and Recommendations Conclusions Recommendations Abbreviations and Acronyms References Appendix A: Survey Questionnaire and Contacts Information Appendix B: Projects in the County of Sacramento Appendix C: Data of RHMA Projects from the City of Sacramento Appendix D: Projects in Leisure World of the Southern California Contractor s Report ii

4 List of Figures Figure 1. Flow Chart of Process Used to Develop Performance Models... 3 Figure 2. The Changes of PCI under Different Values of Parameter Alpha Figure 3. The Changes of PCI under Different Values of Parameter Beta Figure 4. The Changes of PCI under Different Values of Parameter Rho Figure 5. The Changes of PCI under Different Values of Parameter Shift Figure 6. The Changes of PCI under Different Values of Parameter Chi Figure 7. The Changes of PCI for both Asphalt Rubber and Conventional Asphalt Arterial Streets Figure 8. The Changes of PCI for adjusted AC over AC Collector and Residential Reinforced Concrete Asphalt Performance Model Figure 9. Variation of PCI for Adjusted AC over AC Collector, Residential and Arterial Roads Figure 10. The Changes of Projected SDI under Different Values of Parameter A Figure 11. The Changes of Projected SDI under Different Values of Parameter B Figure 12. The Changes of Projected SDI under Different Values of Parameter C Figure 13. The Overall Pavement Quality Index Performance Curve Figure 14. The Changes of SDI under Varying Years since Construction Figure 15. Variation of SDI for Varying Structure Types of after Varying Years of Construction.. 34 Figure 16. Plot of given data from Southern California and estimated curve List of Tables Table 1. List of Streets with 1.5" Overlay used for MTC StreetSaver Modeling Purposes... 6 Table 2 List of Streets with 2" Overlay used for MTC StreetSaver Modeling Purposes... 9 Table 3. Surface Distress Index (SDI) Models for Curve Number Table 4. Southern California Asphalt Rubber Project Data from Manhole Adjusting Table 5. Statistical Results for Non-linear Regression Modeling of for Arterial Streets Table 6. Statistical Results of Non Linear Regression Modeling Table 7. Curve Number Corresponding to Pavement Thickness, Traffic Level, and Foundation Type Table 8. Statistical Results for Non-linear Regression Modeling of Table 9. Statistical Results for Non-Linear Regression Modeling of Table 10. Parameter Estimates for Curve Numbers 18 to Table 11. Parameter Estimates for Curve Numbers 9 to Table 12. Statistical Results from Nonlinear Regression Analysis Table 13. Local Agencies Which Responded to the Survey Table 14. List of Sacramento County Pavements Table 15. Historical Performance Information from the City of Sacramento s PMS Database Table 16. Leisure World Project Information including Location and Estimated PCIs Contractor s Report iii

5 Acknowledgments We appreciate the financial support of the CalRecycle for providing the funding for this important and meaningful study. We would like to extend our gratitude to Nate Gauff and Bob Fujii of CalRecycle, who provided continuous support to this project. We also wish to acknowledge the assistance of Sui Tan of the Metropolitan Transportation Commission, Kenneth Wick of Sacramento County, Mark Brown of City of Sacramento, Fred Stephenson of Stantec, Theron Roschen of Quincy Engineering, Erik Updyke and Imelda Diaz of LA County, and John Corcoran and Harold Smith of Manhole Adjusting who provided information on the long term performance of asphalt rubber mixes in southern California. Contractor s Report iv

6 Executive Summary Although asphalt rubber is not a new treatment technology, there is still much to learn about the performance of asphalt rubber mixes. For example, the long term performance of asphalt rubber pavement is not well documented and performance models of Rubberized Asphalt Concrete () are not readily available for use in pavement management systems used in California (StreetSaver, MicroPAVER, Stantec, and others). This report documents the performance of asphalt rubber projects included in the StreetSaver and Stantec pavement management systems. Since much of the information in these systems are less than 10 years old, it was necessary to visit older projects to determine the long term performance of asphalt rubber mixes so the performance could be compared with conventional hot mix. In this study, California Pavement Preservation Center (CP2 Center) obtained the long term rubberized hot mix asphalt performance information from southern California. The following is a summary of what was accomplished during this study: 1. By studying the equation utilized by MTC StreetSaver, the CP2 Center did an analysis to better understand how this equation works and how it can be manipulated to generate different curve shapes as well as different life pavements. 2. From the analysis done using the San Francisco Bay Area data, it was found that the Alpha and Shift variables have a direct relationship with the projected Pavement Condition Index (PCI). When either Alpha or Shift are increased, the projected PCI will increase as well. However Rho and Chi have inversely proportional relationships with the projected PCI. When either Rho or Chi is increased, the projected PCI will decrease proportionally. The parameter Beta seems to be inversely proportional to the projected PCI during the earlier life of the pavement, and then the parameter of Beta will be directly proportional to the projected PCI during the later years of the pavement s life. 3. An initial nonlinear regression was run on the data set using the computer program SPSS, and CP2 Center developed parameters for a MTC PMS StreetSaver performance model for the case of asphalt concrete over asphalt concrete (AC/AC) for arterial streets. 4. Using the performance model for AC/AC on arterial streets as the base, the CP2 Center created performance models for collector and residential streets, respectively. Based on the performance curves. Residential streets were found to have better performance than arterials and collectors with collectors having about the same performance as the arterials. 5. This study has shown that the parameters A and C of the Stantec S-Curve models (used by the City of Sacramento and Los Angeles County) are inversely proportional to the projected Surface Distress Index (SDI), while the parameter B is directly proportional to the projected SDI. If the parameters A or C are lowered, the SDI will increase, and if the parameter B is lowered, the SDI will lower as well. 6. There are total 18 performance curves for AC overlay for the City of Sacramento. The Central Valley data shows that the Curve 15 (Thick/High/Strong) has the most Rubberized Asphalt Concrete () project data. The CP2 Center first developed the performance model for the Curve 15, and then used the Curve 15 model as the base line. Then the CP2 Center developed performance models for all other curves. pavement with thick Contractor s Report v

7 pavement overlay, low traffic volume, and a strong foundation was shown to have the longest life. Recommended performance models for each of these regions have been developed. The best performance has generally been in southern California. This could be due in part to climate and the quality of the contractors and the materials. It is recommended that continued tracking of the performance of these mixes needs to be done to make sure that the long term performance in the northern California areas are documented correctly. Contractor s Report vi

8 Introduction Background Currently, California generates more than 40 million reuse or waste tires per year. Although the overall diversion rate is about 80%, a portion of that is due to overseas exports and tire derived fuels. The Department of Resources Recycling and Recovery (CalRecycle) has a goal to increase the usage of processing California waste tires into more value added tire-derived products in California. CalRecycle promotes the use of waste tires in various pavement strategies as part of their ongoing efforts to divert waste tires from landfills in California. There are many advantages of utilizing waste tires in pavement. To date, the California Pavement Preservation Center (CP2 Center) has monitored the construction of numerous Caltrans and local agency projects containing asphalt rubber in California including ones with warm mix additives. The oldest asphalt rubber project monitored with warm mix dates back to 2006, and the bulk of the projects constructed in California are not very well documented. Long-term performance and the development of performance models to predict future performance are needed. These are not available at the present time. The CP2 Center, with data provided by the Metropolitan Transportation Commission (MTC), Sacramento County, City of Sacramento, LA County, and Manhole Adjusting, is researching pavement deterioration curves for the purpose of developing new performance models for rubberized hot mix asphalt pavements. Purpose of Report The objective of this report was to create a preliminary performance model using data gathered by various local agencies in California in order to create a model that would work for rubberized hot mix asphalt. To our knowledge, none of the agencies in California have developed a performance model specifically for rubberized hot mix asphalt overlay using asphalt rubber except LA County, which has a performance table. This report is part of a series of reports that were developed as a part of the overall project. The work orders issued for this project consist of the following: Work Order 1: Collect information from local agencies and develop performance curves for rubberized asphalt overlays. Work Order 2: Collect information from Caltrans and develop performance curves for asphalt rubber. Work Order 3: Collect materials from projects in California and perform fatigue tests on conventional and asphalt rubber hot mix to quantify the cracking resistance of each product. Work Order 4: Disseminate the information through reports, papers, and presentations; as well as participation in state and national meetings. This report deals with Work Order 1 only. Contractor s Report 1

9 Organization of the Report The report is organized into the following sections: Section 1. Introduction of the report. Section 2. Describes the methodology used to develop the models for local agencies in California. Section 3. Describes the location of rubberized hot mix projects. There were three regions studied including San Francisco Bay Area, Central Valley, and Southern California. Section 4. Describes the data mining of resources from various local agencies including pavement management databases, and field visits. Section 5. Presents the data analysis and developed performance models for rubberized hot mix overlays. Section 6. Provides the conclusions and recommendations of this study. Contractor s Report 2

10 Methodology To develop new performance models that can be adapted for use with Asphalt Rubber in California, the CP2 Center took the following steps shown in Figure 1. Gather Pavement Mangement System Information from three different regions within California Research applicable models that could be used for modeling Rubberized Asphalt Concrete Collect pavement performance modeling related data from each region and its respective database Filter data gathered for each model Adapt and determine data to fit each model requirement Conduct non-linear regression analysis Create preliminary Rubberized Asphalt Concrete models for each region Figure 1. Flow Chart of Process Used to Develop Performance Models Based on the climate region and location, the CP2 Center divided the California into three major regions: the San Francisco Bay Area, Central California, and Southern California. Then the CP2 Center gathered data from the different regions where the information was derived from a list of projects received CalRecycle Grants. The CP2 Center also used information from Local agencies that were given in response to a questionnaire sent out by the Center. The questionnaire and contacts of the agencies that responded to the survey are listed in Appendix A. Prior to work on this report, a literature review was completed which researched various models that would be applicable to the local agencies in California. The two pavement performance models that the CP2 Center moved forward with were e MTC StreetSaver model and Stantec RoadMatrix model model (1). In order to accomplish our work, the CP2 Center had to filter and sort information from the databases of the two models so they could be modified for use with overlays. This is to Contractor s Report 3

11 make sure inadequate or irrelevant data was not included in the new model, the CP2 Center eliminated information if the treatment type could not be confirmed, incomplete information, no information post-treatment, and if it were believed that a maintenance treatment had been done but not reported in the database. In order to use the data from the database, data must be sorted to fit the new model requirement. For the MTC StreetSaver program, the rubberized hot mix overlay projects were sorted by different thicknesses, AC over AC, functional class of roadways, and pavement age. For the Stantec RoadMatrix program, the rubberized hot mix overlay projects were sorted into different pavement thicknesses, traffic levels, and foundation strengths. After the data was filtered and sorted to fit this new asphalt rubber model requirements, CP2C used IBM s Statistical Package for the Social Sciences (SPSS) to perform a non-linear regression analysis (2). A non-linear regression analysis was used in order to develop consistent models for both StreetSaver and RoadMatrix. The results of the SPSS analysis were preliminary models for each region. For San Francisco Bay Area, the models the CP2 Center developed were based on pavement thicknesses, functional classes, and pavement types. Not every category had enough data for the analysis. When the amount of data for a specific category was limited, no model was generated for that category. For the central valley area (City of Sacramento), the models were developed based on thicknesses of asphalt rubber overlays, traffic levels, and strength of subgrade foundations. For the central valley region, more long term performance of projects was needed for accurate modeling.. As the City of Sacramento continues to collect more projects data, the CP2 Center s model can be revisited, and refined. The following is more information on the locations of the projects evaluated. San Francisco Bay Area The Metropolitan Transportation Commission (MTC) was very supportive of the project, and the MTC gave the CP2 Center the access to their StreetSaver Databases. Many CalRecycle Grant Project locations were found in this database. As the transportation planning, coordinating and financial agency for the San Francisco Bay Area, the MTC maintains a street condition database in order to manage and monitor the overall condition of the streets for funding and maintenance purpose for the pavement roadway network in the San Francisco Bay Area. The ages of the projects from the San Francisco Bay Area region of California ranged from 0 to 6 years old. Central Valley Located in the Northern Area of the Central Valley, Sacramento County has also given PCI information in the form of StreetSaver PCI. The PCI values correspond to a mid to long term PCI information of the County streets and highways. In addition to Sacramento County, the City of Sacramento has also given CP2 Center access to their pavement management database, RoadMatrix TM (3). The information was very helpful for developing the rubberized hot mix asphalt performance models. The ages of the projects from the central valley region of California range from 3 to 8 years old for the City of Sacramento. Contractor s Report 4

12 Southern California The initial data received by the CP2 Center was from the San Francisco Bay Area. These projects are all relatively new pavements. In order to have a more fully comprehensive curve in which takes into account the long term conditions of asphalt rubber pavements, projects from outside of the SF Bay Area had to be considered. Southern California has a longer history of using asphalt rubber pavements. The ages of the pavement projects from Southern California range from 12 to 25 years old. The CP2 Center gathered project information during two visits to projects constructed and shown by Manhole Adjusting Company in southern California. Manhole Adjusting Company took Dr. Gary Hicks and Dr. DingXin Cheng, of the CP2 Center, on tours to various locations where they had previously constructed these projects. Dr. DingXin Cheng also visited some projects in the Los Angeles County. Contractor s Report 5

13 Data Mining of Resources This chapter describes the process used to mine data to develop the models. It consisted of reviewing the following information: CalRecycle Public Grant List MTC Street Saver Database City and County of Sacramento Southern California projects Others CalRecycle Public Grant List The CalRecycle list of grants published on the CalRecycle websites was used as a starting point for the locations of known rubber projects. The links to these various grant projects are and CalRecycle Grants Listed By County Search. Many grant projects published on the list included contact information, and the street locations. These grant projects were cross-referenced with the MTC StreetSaver Database to help select projects for analysis in the San Francisco Bay area and in southern California. Data from these projects was used to develop the regression analysis models. MTC StreetSaver Data Table 1 and Table 2 consist of the data gathered from various Bay Area Cities and Counties and used for our modeling purposes. They are grouped into two categories: 1.5 and Overlay 2. There are 50 projects using 1.5 shown in Table 1 and 58 projects using 2 overlay shown in Table 2. The tables have the details for each roadway that was analyzed. The Section ID and street name give the location that was examined. The pavement type is shown for each section of roadway as well as the functional class. The functional classes include Arterial, Collector, and Residential streets. The construction date, years since construction, and PCI are also listed to compare how each pavement has been performing since completion. Since the oldest project is only 6 years old, the CP2 Center s model will need to be revisited, and refined as more history data is collected for the San Francisco Bay area projects in the future. Table 1. List of Streets with 1.5" Overlay used for MTC StreetSaver Modeling Purposes Section ID Street Name Pavement Type Allendale Dr AC/AC Allendale Dr AC/AC Cantelow Road AC/AC City / County Solano County Solano County Solano County Functional Class Const. Date Years Since Const. PCI Rural Major Collector 7/29/ Rural Major Collector 7/29/ Rural Major Collector 7/29/ Contractor s Report 6

14 Section ID Street Name Cantelow Road Pavement Type AC/AC Lewis Road AC/AC Lewis Road AC/AC Sweeney Road AC/AC Putah Creek Rd AC/AC Putah Creek Rd AC/AC Putah Creek Rd AC/AC Putah Creek Rd AC/AC Putah Creek Rd AC/AC Putah Creek Rd AC/AC Putah Creek Rd AC/AC Putah Creek Rd AC/AC Putah Creek Rd AC/AC Putah Creek Rd AC/AC Putah Creek Rd AC/AC Putah Creek Rd Putah Creek Rd Putah Creek Rd Putah Creek Rd Putah Creek Rd AC/AC AC/AC AC/AC AC/AC AC/AC Runge Rd AC/AC Tremont Rd AC/AC City / County Solano County Solano County Functional Class Const. Date Years Since Const. PCI Rural Major Collector 7/29/ Rural Major Collector 7/29/ Solano County Rural Major Collector 7/29/ Solano County Rural Local 7/29/ Solano Rural Major County Collector 7/29/ Solano Rural Major County Collector 7/29/ Solano Rural Major County Collector 7/29/ Solano Rural Major County Collector 7/29/ Solano Rural Major County Collector 7/29/ Solano Rural Major County Collector 7/29/ Solano Rural Major County Collector 7/29/ Solano Rural Major County Collector 7/29/ Solano Rural Major County Collector 7/29/ Solano Rural Major County Collector 7/29/ Solano Rural Major County Collector 7/29/ Solano County Rural Major Collector 7/29/ Solano Rural Major County Collector 7/29/ Solano Rural Major County Collector 7/29/ Solano Rural Major County Collector 7/29/ Solano Rural Major County Collector 7/29/ Solano County Rural Local 7/29/ Solano Rural Major County Collector 7/29/ Contractor s Report 7

15 Section ID Street Name Pavement Type City / County Functional Class Const. Date Years Since Const Tremont Rd AC/AC Solano County Rural Major Collector 7/29/ Casey Rd AC Solano County Rural Local 7/29/ Casey Rd AC Solano County Rural Local 7/29/ Robben Rd AC/AC Solano County Rural Local 7/29/ Schroeder Rd AC/AC Solano County Rural Local 7/29/ Green Valley Solano Rural Major Rd AC/AC County Collector 6/20/ Green Valley Rd AC/AC Solano County Rural Major Collector 6/20/ N S. Park Victoria Dr. AC/AC Milpitas Arterial 11/1/ N S. Park Victoria Dr. AC/AC Milpitas Arterial 11/1/ N S. Park Victoria Dr. AC/AC Milpitas Arterial 11/1/ N S. Park Victoria Dr. AC/AC Milpitas Arterial 11/1/ N S. Park Victoria Dr. AC/AC Milpitas Arterial 11/1/ N S. Park Victoria Dr. AC/AC Milpitas Arterial 11/1/ N S. Park Victoria Dr. AC/AC Milpitas Arterial 11/1/ N S. Park Victoria Dr. AC/AC Milpitas Arterial 11/1/ N S. Park Victoria Dr. AC/AC Milpitas Arterial 11/1/ N S. Park Victoria Dr. AC/AC Milpitas Arterial 11/1/ N S. Park Victoria Dr. AC/AC Milpitas Arterial 11/1/ N S. Park Victoria Dr. AC/AC Milpitas Arterial 11/1/ N S. Park Victoria Dr. AC/AC Milpitas Arterial 11/1/ N S. Park Victoria Dr. AC/AC Milpitas Arterial 11/1/ N S. Park Victoria Dr. AC/AC Milpitas Arterial 11/1/ PCI Contractor s Report 8

16 Section ID 0140N 0140N 0140N Street Name Pavement Type City / County Functional Class Const. Date Years Since Const. S. Park Victoria Dr. AC/AC Milpitas Arterial 11/1/ S. Park Victoria Dr. AC/AC Milpitas Arterial 11/1/ S. Park Victoria Dr. AC/AC Milpitas Arterial 11/1/ PCI Table 2 List of Streets with 2" Overlay used for MTC StreetSaver Modeling Purposes Section ID Street Name Pavement Type City / County Functional Class Const. Date Years Since Const. 40 Fernside Blvd AC/AC Alameda Collector 8/30/ Fernside Blvd AC/AC Alameda Collector 8/30/ Central Ave AC/AC Alameda Arterial 8/31/ Central Ave AC/AC Alameda Arterial 8/31/ Central Ave AC/AC Alameda Arterial 8/31/ Central Ave AC/AC Alameda Arterial 8/31/ Diablo Rd AC/AC Danville Arterial 6/27/ Diablo Rd AC/AC Danville Arterial 6/27/ A020 Diablo Rd AC/AC Danville Arterial 6/27/ A020 Diablo Rd AC/AC Danville Arterial 6/27/ Diablo Rd AC/AC Danville Arterial 6/27/ Diablo Rd AC/AC Danville Arterial 6/27/ N Grimmer Blvd AC/AC Fremont Arterial 11/1/ N Grimmer Blvd AC/AC Fremont Arterial 11/1/ N Grimmer Blvd AC/AC Fremont Arterial 11/1/ S Grimmer Blvd AC/AC Fremont Arterial 11/1/ S Grimmer Blvd AC/AC Fremont Arterial 11/1/ S Grimmer Blvd AC/AC Fremont Arterial 11/1/ N Grimmer Blvd AC/AC Fremont Arterial 11/1/ N Grimmer Blvd AC/AC Fremont Arterial 11/1/ N Grimmer Blvd AC/AC Fremont Arterial 11/1/ S Grimmer Blvd AC/AC Fremont Arterial 11/1/ S Grimmer Blvd AC/AC Fremont Arterial 11/1/ S Grimmer Blvd AC/AC Fremont Arterial 11/1/ N Grimmer Blvd AC/AC Fremont Arterial 11/1/ N Grimmer Blvd AC/AC Fremont Arterial 11/1/ N Grimmer Blvd AC/AC Fremont Arterial 11/1/ S Grimmer Blvd AC/AC Fremont Arterial 11/1/ S Grimmer Blvd AC/AC Fremont Arterial 11/1/ S Grimmer Blvd AC/AC Fremont Arterial 11/1/ PCI Contractor s Report 9

17 Section ID Street Name Pavement Type City / County Functional Class Const. Date Years Since Const. 01 Palm Ave AC/AC Fremont Arterial 6/1/ Palm Ave AC/AC Fremont Arterial 6/1/ Palm Ave AC/AC Fremont Arterial 6/1/ Moraga Way (A12001) AC/AC Orinda Arterial 7/1/ Moraga Way (A12001) AC/AC Orinda Arterial 7/1/ Moraga Way (A12001) AC/AC Orinda Arterial 7/1/ Moraga Way (A12001) AC/AC Orinda Arterial 7/1/ Moraga Way (A12001) AC/AC Orinda Arterial 7/1/ Moraga Way (A12001) AC/AC Orinda Arterial 7/1/ Moraga Way (A12001) AC/AC Orinda Arterial 7/1/ Moraga Way (A12002) AC/AC Orinda Arterial 7/1/ Moraga Way (A12002) AC/AC Orinda Arterial 7/1/ Moraga Way (A12002) AC/AC Orinda Arterial 7/1/ Moraga Way (A12002) AC/AC Orinda Arterial 7/1/ Moraga Way (A12002) AC/AC Orinda Arterial 7/1/ Moraga Way (A12002) AC/AC Orinda Arterial 7/1/ Moraga Way (A12002) AC/AC Orinda Arterial 7/1/ Moraga Way (A12002) AC/AC Orinda Arterial 7/1/ Moraga Way (A12002) AC/AC Orinda Arterial 7/1/ Moraga Way (A12002) AC/AC Orinda Arterial 7/1/ Moraga Way (A12002) AC/AC Orinda Arterial 7/1/ Moraga Way (A12002) AC/AC Orinda Arterial 7/1/ Moraga Way (A12002) AC/AC Orinda Arterial 7/1/ Moraga Way (A12002) AC/AC Orinda Arterial 7/1/ PCI Contractor s Report 10

18 Section ID Street Name Pavement Type City / County Functional Class Const. Date Years Since Const. Moraga Way (A12002) AC/AC Orinda Arterial 7/1/ Adobe Rd AC/AC Sonoma Arterial 10/25/ Adobe Rd AC/AC Sonoma Arterial 10/24/ Adobe Rd AC/AC Sonoma Arterial 10/24/ PCI City and County of Sacramento TheCP2 Center had two resources to use from the central valley area, the City of Sacramento and the County of Sacramento. They use two different pavement management systems, Stantec RoadMatrix for the City of Sacramento, and MTC StreetSaver for the County of Sacramento. The data given to CP2 Center by the City of Sacramento included a database and a document explaining the management system. CP2 Center collected data on 409 projects known to be pavements to be analyzed for our modeling purpose. Although there were 409 total projects, there are many more data points used in the model. These points represent the historical inspection information, which were used to develop the pavement -performance curves. County of Sacramento Street Saver data was given to the CP2 Center by the County of Sacramento and are listed in Appendix B. This data was not used in the final modeling for MTC StreetSaver for the central valley. This is partially due to the fact that pavement thickness information is unknown for these locations. For future work, some of this data could be better utilized with core data to verify overlay thicknesses, and this additional data would add further refinement to the model. These projects have a longer history than many of the projects that were used in this analysis. City of Sacramento There are more than 1500 survey points were collected from the city of Sacramento. And there are total of 18 different curve types which represent different AC layer thickness, traffic level, and strength of subgrade foundation. Only the curve Number 15, which represents a thick overlay, with a high traffic volume, and strong subgrade, was presented in Table 3. Table 3contains the information from the type 15 pavement. The section ID, section history work location, and years since construction give the location that was examined and how long ago the pavement was constructed. The SDI value and the date the SDI value determined are shown to compare the performance of the pavements over time. Of the eighteen various pavements, the curve Number 15 was the most widely used of the data set. The full dataset is listed in Appendix C of this report. The high use of this particular curve number is the reasoning for why it was used to determine the parameter estimates for variables, A, B, and C for the S-shape performance curves of the Stantec model. Contractor s Report 11

19 Table 3. Surface Distress Index (SDI) Models for Curve Number 15 Section ID Street Location ID Street Name PER_SDI Date Years Since Const. SDI PER_SDI L ST 09-Sep TH ST 22-Aug TH ST 22-Aug NB SB NB SB NB SB NB NB 23-Sep Sep Sep Sep Sep Sep Jul Jul L ST SB 10-Jul TH ST NB 19-Aug RD AVE 01-Aug SB SB SB NB 21-Jul Mar Aug Jul Contractor s Report 12

20 Section ID Street Location ID Street Name PER_SDI Date Years Since Const. SDI PER_SDI TH ST NB SB NB SB NB SB SB NB NB NB NB NB NB 27-Nov Mar Mar Jul Jul Nov Aug SB NB NB 27-Nov Jul NB SB 10-Jul Contractor s Report 13

21 Section ID Street Location ID Street Name PER_SDI Date Years Since Const. SDI PER_SDI SB NB SB 21-Jul Nov Mar RD AVE SB 19-Aug RD AVE 13-Aug RD AVE 01-Aug SB 27-Nov NB SB SB SB 10-Jul Jul TH ST 22-Jul TH ST 26-Nov NB SB 21-Mar Mar TH ST 09-Jul TH ST 26-Mar TH ST 09-Jul L ST TH ST 26-Mar TH ST 26-Mar SB 19-Aug Contractor s Report 14

22 Section ID Street Location ID Street Name PER_SDI Date Years Since Const. SDI PER_SDI SB SB 27-Nov L ST 22-Mar L ST 22-Mar TH ST 22-Jul TH ST TH ST 26-Nov NB NB 19-Aug TH ST NB 19-Aug Southern California Pavement Projects Table 4 shows the collected project information from the first visit of the southern California by the CP2 Center in September The CP2 Center visited various project sites in the southern California and evaluated the conditions of these projects. Based on the rating of the conditions, the PCIs were estimated. The CP2 Center made the second visit to the southern California in December During the visit, more than 150 projects were surveyed by both the CP2 Center and Manhole Adjusting. These overlay projects were built between 1993 and 2002 which gave the pavement project performance information over a range of years. The detailed location and other information of these projects are listed in Appendix D of this report. Table 4. Southern California Asphalt Rubber Project Data from Manhole Adjusting Street Name Location Type of project Previous Pavement Condition Condition PCI Equivalent Current Age Current Pavement Condition Condition PCI Equivalent Wake Forest Ave. Ventura ARAM/ ARHM Poor Good 65 Walnut Grove Ave Rosemead ARAM/ ARHM Fair Fair 55 Contractor s Report 15

23 Street Name Rosemead Blvd, CA-19 San Gabriel Blvd Valley Blvd Katella Ave Randolph Ave Philadelphia Street Camilla Street Norino Street Interstate 5 (near Glendale Exit) First Street Gracebee Avenue Concourse Ave* Access Road to Dump Site Location Type of project Previous Pavement Condition Condition PCI Equivalent Current Age Current Pavement Condition Condition PCI Equivalent Rosemead AR Chip Unknown N/A 25 Fair 55 Rosemead Rosemead Los Alamitos Costa Mesa Whittier Whittier Whittier LA County Santa Ana Norwalk LA County Monterey Park ARHM/ 2 ARHM ARHM/ 2 ARHM 1.5 ARHM/ ARAM ARAM Cape Seal 1.5 ARHM/ AC ARAM Cape Seal ARAM Cape Seal 1.8 ARHM Overlay ARHM/ ARAM ARAM Cape Seal ARAM Cape Seal Large Stone ARAM Unknown N/A 22 Good 65 Unknown N/A 14 Good 65 Unknown N/A 17 Fair 50 Poor Good 65 Poor Fair/Good 55 Fair/Poor Good 65 Fair/Poor Fair 60 Poor Fair 55 Poor Fair/Good 60 Poor Fair/Good 60 Unknown N/A 29 Fair 50 Poor Poor 40 * Majority of this project was reconstructed in 2003 with only a few remaining sections of 1984 ARAM Cape Seal Contractor s Report 16

24 Data Analysis and Performance Models This chapter presents the results of the data analysis and the development of the performance models using the data mentioned in the preceding chapter. The data from the San Franciso Bay area, the City of Sacramento and for southern California were used to develop the models. San Francisco Bay Area As discussed earlier, the Pavement Management System used in the Bay Area is MTC StreetSaver. It is a program developed by the MTC in order to have a standard pavement management system and comparison among the cities and counties of the Bay Area. The model used by MTC is shown in Equation 1. It is used for both asphalt concrete (AC) and Portland Concrete Cement (PCC) pavement types. It is adapted to each pavement type through the change in modifier and constants; however, it does not have constants for asphalt rubber pavements at the present time (4, 5, 6). ( ( )) (1) where =Projected Pavement Condition Index Value = Years since the last major rehabilitation/reconstruction activity = A projection modifier, initially set to 0 = Regression constant that controls the age in which the curve is asymptomatic = Regression constant that controls how sharply the PCI family curve bends = Regression constant that controls the age at which the inflection point in the PCI family curve = A projection modifier, initially set to 1 StreetSaver has many components to it, in both pavement evaluation and cost effectiveness. For its pavement evaluation component an s-curve is used to more accurately portray the pavement deterioration over time. The regression constants, α, β, and ρ, used to control the graphs are dependent upon functional class and type of pavement. The projection modifiers, χ and Shift, are dependent on different maintenance treatments and are customized on a street section level. Values for χ and Shift start at 0 and 1 respectively, but can be changed post-treatment. Typically, a new family curve is created after a major rehabilitation or reconstruction is done to a section. However, as a method of comparison within StreetSaver, two curves are projected: a family curve and an adjusted curve. This adjusted curve is changed due to inspections and maintenance treatments, which make the curve more accurate and reflect the life of the pavement. To have a better understanding of the parameters for the StreetSaver family curve, the CP2 Center has studied the role of each parameter in the following section. Contractor s Report 17

25 PROJECTED PAVEMENT CONDITION INDEX (PCI) Figure 2 shows the variation of the projected Performance Condition Index (PCI) performance curves when varying the value of Alpha and keeping the other parameters constant. The values for Alpha range from 40 to 80. As the value of Alpha increases the projected PCI value will increase as well and lead to a longer life of a pavement Variation of Alpha Values to Projected PCI Alpha 40 Alpha Alpha 60 Alpha 70 Alpha AGE (YEARS) Figure 2. The Changes of PCI under Different Values of Parameter Alpha Contractor s Report 18

26 PROJECTED PAVEMENT CONDITION INDEX (PCI) Figure 3 shows the variation of the projected Pavement Condition Index (PCI) performance curves when varying the value of Beta and keeping the other parameters constant. The values of Beta range from 0.5 to 1. As the value of Beta increases the initial response will be for the projected PCI to decrease, but towards the end of the pavement s life the performance will increase and lead to a longer life of a pavement Variation of Beta Values to Projected PCI Beta.5 Beta.6 Beta.7 Beta Beta Beta AGE (YEARS) Figure 3. The Changes of PCI under Different Values of Parameter Beta Contractor s Report 19

27 PROJECTED PAVEMENT CONDITION INDEX (PCI) Figure 4 shows the variation of the projected Pavement Condition Index (PCI) performance curves when varying the value of Rho and keeping the other parameters constant. The values of Rho range from 30 to 70. As the value of Rho increases, the projected PCI will decrease and lead to a shorter life span for a pavement Variation of Rho Values to Projected PCI Rho Rho 40 Rho 50 Rho Rho AGE (YEARS) Figure 4. The Changes of PCI under Different Values of Parameter Rho Contractor s Report 20

28 PROJECTED PAVEMENT CONDITION INDEX (PCI) Figure 5 shows the variation of the projected Pavement Condition Index (PCI) performance curves when varying the Shift value and keeping the other parameters constant. The Shift values range from 0 to 40. As the shift value increases, the value of the projected PCI will increase as well, and lead to a longer life of a pavement Variation of Shift Values to Projected PCI Shift 0 Shift 1 Shift Shift Shift 20 Shift AGE (YEARS) Figure 5. The Changes of PCI under Different Values of Parameter Shift Contractor s Report 21

29 PROJECTED PAVEMENT CONDITION INDEX (PCI) Figure 6 shows the variation of the projected Pavement Condition Index (PCI) values when varying the value of Chi and keeping the other parameters constant. The range of the Chi values range from zero to three. As the value of Chi increases, the projected PCI will decrease leading to a shorter life of the pavement. Variation of Chi Values to Projected PCI Chi.8 Chi Chi 1.2 Chi Chi 2 Chi AGE (YEARS) Figure 6. The Changes of PCI under Different Values of Parameter Chi Contractor s Report 22

30 Pavement Condition Index (PCI) After evaluating the parameters used in the StreetSaver family curve, the CP2 Center conducted a non-linear regression analysis using the overlay information from the San Francisco Bay Area. Figure 7 depicts a comparison of the conventional asphalt pavement for arterial streets to asphalt rubber pavement for arterial streets. From the graph in Figure 7, it is clear that the has the longer life for the arterial streets in the San Francisco Bay area. Due to the lack of long term performance data, some southern California data was utilized to predict the long term performance. As the pavement reaches a later point in life, the PCI has a larger variance as showed in Figure 7. A normal distribution was assumed for the variations of PCIs at different pavement ages. The curves of normal distribution are shown in the figure at ages of 3, 13, and 20 years, respectively Asphalt Rubber vs. Conventional Asphalt for Arterial Streets Performance Data Conventional HMA Family Curve New Family Curve Distribution at year 3 Distribution at Year 13 Distrubution at Year Age of Pavement (Year) Figure 7. The Changes of PCI for both Asphalt Rubber and Conventional Asphalt Arterial Streets Contractor s Report 23

31 Pavement Condition Index (PCI) Table 5 contains the nonlinear regression analysis run statistical results on the San Francisco Bay Area. The results for the sum of the squares, degrees of freedom, as well as the mean squares values are contained in Table 5. The R-square of shows that there exists a huge variation in the pavement performance data, but with more long term data the R2 non-linear regression analysis should improve. Table 5. Statistical Results for Non-linear Regression Modeling of for Arterial Streets ANOVA a Source Sum of Squares Df (1) Mean Squares Regression Residual Uncorrected Total Corrected Total Dependent variable: PCI a. R squared = 1 (Residual Sum of Squares) / (Corrected Sum of Squares) =.498. (1) Degree of freedom Figure 8 depicts the graphs comparing Collector and Residential pavement models with conventional family curves. The same approach was used to develop this graph as for the prior one Collector and Residential AC/AC Performance Models Collector ADJ Residential ADJ Collector Residential AC/AC Residential Age of Pavement (Years) Figure 8. The Changes of PCI for adjusted AC over AC Collector and Residential Reinforced Concrete Asphalt Performance Model Contractor s Report 24

32 Pavement Condition Index (PCI) Figure 9 summarizes the developed performance models for Arterial, Collector, and Residential streets on an AC over AC pavement type. It is clear to see that the Arterial roadway has the shortest life, and the Residential performed the best and had a significantly longer life than the Collector and Arterial roadways. The longer life for Resident roadways is due to a lower truck volume and a lower traffic volume. Also, much distress in Arterials is at or near traffic lights, and most residential roadways are not subjected to as many distresses caused by traffic stopping at higher speed and then accelerating. Trucks stopped for longer period of time cause stresses that are more detrimental to the life of the pavement because the pavement deflects more over the additional time where the truck is stopped. Both of these traffic patterns cause rutting and shoving. The truck traffic also tends to cause fatigue cracking in the wheel tracks over time. 120 AC/AC () 100 Arterial 80 Collector Residential 60 Data Point Age of Pavement (Years) Figure 9. Variation of PCI for Adjusted AC over AC Collector, Residential and Arterial Roads Contractor s Report 25

33 Central Valley The City of Sacramento evaluates their pavement using the Stantec Model much like the Arizona Department of Transportation (DOT). The Arizona DOT s performance model for Pavement Service Rating (PSR) is shown in Equation 2 where the key difference in the methods is the inclusion of different indexes. The City of Sacramento uses the Pavement Quality Index (PQI) and has different indices used to get the overall pavement quality (PQI) including Surface Distress Index (SDI), Riding Comfort Index (RCI), and Structural Adequacy Index (SAI). Each index is on a scale from 0 to 100. The City of Sacramento s SDI is equivalent to Arizona s Pavement Service Rating (PSR) items such as Patching, Rippling & Shoving, Raveling, and Streaking, although SDI accounts for many more types of distresses. In this study, the equations to modeling PQI and SDI versus age of pavement are shown in Equations 3 and 4, respectively(2,7,8).. - ( - ) (2) ( ( ) ) (3) ( ( ) ) (4) where, = Initial Conditions = The number of year since the last rehabilitation or construction activity = Coefficients that define the model shape In order to determine how parameters A, B, and C affect the performance curves in the above equation, a sensitivity study was performed by the CP2 Center similar to that done for the MTC StreetSaver method. Contractor s Report 26

34 PROJECTED SURFACE DISTRESS INDEX (SDI) Figure 10 shows the variation of the projected Surface Distress Index (SDI) performance curves when varying the value of A and keeping the other parameters constant. The range for the value of A is from 16.5 to As the value of A increases, the projected SDI will decrease and lead to a shorter life of a pavement. Variation of A to Projected SDI A= A=16.7 A=16.93 A=17.2 A= AGE (YEARS) Figure 10. The Changes of Projected SDI under Different Values of Parameter A Contractor s Report 27

35 PROJECTED SURFACE DISTRESS INDEX (SDI) Figure 11 shows the variation of the projected Surface Distress Index (SDI) performance curves when varying the value of B and keeping the other parameters constant. The range for the value of B is from 15.0 to As the value of B increases the projected SDI increases and will lead to a longer life of a pavement. Variation of B to Projected SDI B=15 B= B= B=15.7 B= AGE (YEARS) Figure 11. The Changes of Projected SDI under Different Values of Parameter B Contractor s Report 28

36 PROJECTED SURFACE DISTRESS INDEX (SDI) Figure 12 shows the variation of the projected Surface Distress Index (SDI) performance curves when varying the value of C and keeping the other parameters constant. The range for the value of C is from to 1.1. As the value of C increases, the projected SDI will decrease and lead to a shorter life of a pavement. Variation of C to Projected SDI C= C= C= C=1.08 C= AGE (YEARS) Figure 12. The Changes of Projected SDI under Different Values of Parameter C Contractor s Report 29