2019 Pavement Workshop May 21-23, 2019 Improve Material Inputs into Mechanistic Design Properties for RCA & RAP Bora Cetin Assistant Professor Iowa State University + 46 Associate Members

RESEARCH TEAM Iowa State University GeoEngineering Consulting, LLC Principal Investigator – Bora Cetin Assistant Professor – Department of Civil, Construction & Environmental Engineering Research Personnel – Patrick Bollinger PhD Student – Department of Civil, Construction & Environmental Engineering GeoEngineering Consulting, LLC Co-Principal Investigator – Tuncer B. Edil President and Chief Engineer

OUTLINE Introduction Research motivation Objectives Research plan Future expectations

INTRODUCTION Base Course HMA/PCC/Granular Subgrade

INTRODUCTION 2 billion tons/year aggregate produced (FWHA 2004) 200 million tons/year of RCA and 90 million tons/year of RAP generated (FHWA 2011) http://www.gratechcompanyltd.com/aggregate.htm

INTRODUCTION Annual Quantity Used RAP RCA From Edil et al. (2012)

Use of Material Characteristics INTRODUCTION Use of Material Characteristics Pavement M-E Design AASHTO 1993

INTRODUCTION Range of Materials Reclaimed Asphalt Pavement Unbound Materials Reclaimed Asphalt Pavement Fine-Grained Soils Recycled Concrete Aggregate Stabilized Soils Macadam

OBJECTIVES 1st Goal – Establish a database for RAP and RCA materials` characteristics: Resilient modulus (Mr) CBR/UCS Index properties Construction specifications 2nd Goal – Form a pavement design specification

RESEARCH PLAN Task 1 – Initial memorandum on expected research benefits and potential implementation steps Task 2 – Data collection Task 3 – Sensitivity Analyses Task 4 – Draft/final report

Task 2-Data Collection Characterization of RAP & RCA Stiffness/Resilient modulus (Mr) Permanent deformation Shear strength Index properties Hydraulic conductivity/permeability

Task 3-Sensitivity Analyses Normalized Sensitivity Index (NSI) NSI = ∆𝑌 𝐷𝐿 ∆𝑋 𝑋 ∆Y = the change in pavement performance due to change in design input DL = the design limit for the pavement performance parameter ∆X = the change in the design input from the baseline X X = the baseline design input value

Task 3-Sensitivity Analyses IRI = Roughness LC = Longitudinal Cracking AC = Alligator Cracking AR = Asphalt Rutting TR = Total Rutting

Task 4-Draft/Final Report Given the complexity of the system and dynamics of Iowa’s ever-changing granular road conditions due to: Traffic, seasonal and weather conditions, and heavy ag loading; Conditions can change in hours rather than years, so surface condition (although important to know for maintenance purposes); is an ongoing effort and what we really interested in knowing is whether the system can withstand these pressures and continue to provide the desired service to the public. GRAMS proposes to develop a user-friendly, systemic, risk-based evaluation tool to Allow county engineers to better -Tell the Story of Iowa low-vol roads to the public and elected officials. -Perform meaningful Technical analysis, Based on objective criteria that supports tried and true rule-of-thumb decision making, -As well as providing a tool to optimize granular resurfacing strategies and policies.

SCHEDULE

Thank You