Flexible Pavement Construction

Common types of flexible pavement include hot mix asphalt (HMA), rubberized hot mix asphalt-gap graded (RHMA-G), and open graded friction course (OGFC). There are also two types of rubberized OGFC mixes: rubberized hot mix asphalt-open graded (RHMA-O) and RHMA-O-high-binder (RHMA-O-HB).

The engineering design of flexible pavement structures is not an exact science. It is not possible to formulate one set of design criteria that could meet the requirements of every road everywhere. Traffic conditions, climate, geology, materials, construction, and economics are variables that demand the fullest application of professional engineering judgment and skills.

Flexible Pavement Standards

• California Highway Design Manual (HDM): Chapter 630 - Flexible Pavement (PDF)  
  • CT 356: Methods of Test to Obtain Flexible Pavement Deflection Measurements for Determining Pavement Rehabilitation Requirements (PDF) 
• DIB 79-03: Design Guide and Standards for Roadway Rehabilitation Projects (PDF)
• DIB 81: Capital Preventive Maintenance (CAPM) Guidelines (PDF) 
• DIB 86: Selecting Asphalt Binder Type has been incorporated into the July 1, 2008 updated edition of the HDM and the DIB 86 has been discontinued.

Flexible Pavement Guidance

General

• Site Investigation Guide 
• Guide to Partial Depth and Full Depth Recycling
• Guide for Flexible Pavement Rehabilitation Using Pulverization
• Guidelines for Identifying and Repairing Localized Areas of Distress in Asphalt Concrete Pavements Prior to Capital Preventive Maintenance or Rehabilitation Repairs 
• Pavement Tapers & Transitions 
• Shoulder Backing Guidelines 
• Paving over Existing Striping, Markings, and Pavement Markers 

Rubberized Hot Mix Asphalt (RHMA)

• Asphalt Rubber Usage Guide (PDF)
• RHMA Research
  • Synthesis of Caltrans RAC Projects (PDF)
  • Resource Conservation
    • Use of Scrap Tire Rubber (PDF) (PDF, 847KB)
    • Feasibility of Recycling Rubber-Modified Paving Materials (PDF)     

Open Graded Friction Course (OGFC)

• Open Graded Friction Course Usage Guidelines (PDF)

Preservation and Maintenance

• Maintenance Technical Advisory Guide
• Flexible Roadbed Maintenance Repairs ("A" Family) (PDF)
• Pavement Tapers & Transitions (Interim) (PDF)
• Sealing over Existing Striping, Markings, and Pavement Markers (PDF)

Cold Recycling 

• Cold In-Place Recycling 
  • Partial Depth Recycling (PDR)
  • Full Depth Recycling (FDR)
    • Full Depth Recycling-No Stabilizer (FDR-N)
    • Full Depth Recycling-Foamed Asphalt (FDR-FA)
    • Full Depth Recycling-Cement (FDR-C)
• Cold Central Plant Recycling (CCPR)

Flexible Pavement Design Examples

• New Construction/Reconstruction (PDF) | Metric (PDF)
• Rehabilitation (PDF) (PDF, 270KB)

Flexible Pavement Materials

• Performance Graded (PG) Binders 

Flexible Pavement Cost Estimating and Planning

• Alternative Procedure to Estimate Flexible Pavement Rehabilitation Requirements for Project Scoping (PDF)
  • Implementation Memorandum (PDF)

Flexible Pavement Construction

• Hot Mix Asphalt Construction 

Flexible Pavement Research

• Interim Report - Construction Completion for Cold-In-Place Recycling (PDF)
• Final Completion Report - Cold Foam In Place Reclamation (PDF)     
• RHMA Research
  • Synthesis of Caltrans RAC Projects (PDF)

Frequently Asked Questions (FAQ)