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Cover of Aggregate Wetting and Initial Adhesion of Sprayed Sealing Binders
Aggregate Wetting and Initial Adhesion of Sprayed Sealing Binders
  • Publication no: AP-T210-12
  • ISBN: 978-1-921991-48-6
  • Published: 10 October 2012

Cutting solvents have been traditionally added to binders used in sprayed sealing in Australia and New Zealand to ensure that effective adhesion occurs between binder and aggregate. Recent Polymer modified binder (PMB) sealing failures, which have been caused by aggregate stripping shortly after construction, have suggested that higher cutter levels than those currently used for PMBs are needed. Aggregate wetting experiments were conducted with C170, S10E, S20E and S35E binders using a published experimental method in order to determine whether changes to recommended PMB cutter levels were required. Use of the published method gave recommended cutter levels that are likely to be too high to be used in practical applications. Modifications to the published method have been proposed so that PMB cutter levels that are appropriate for use in the field can be determined. Investigations were also conducted into the effects of binder-aggregate contact time and aggregate precoating on the wetting of aggregate by C170, S10E, S20E and S35E binders.

  • 1. INTRODUCTION
  • 2. EXPERIMENTAL DESIGN
    • 2.1. Materials
    • 2.2. Test Procedures
    • 2.3. Methods
      • 2.3.1. Preparation of Binder/Cutter Blends and Precoating Solutions
      • 2.3.2. Aggregate Preparation and Precoating Method
      • 2.3.3. Adhesion Testing
  • 3. RESULTS AND DISCUSSION
    • 3.1. Binder Testing
    • 3.2. Initial Adhesion
      • 3.2.1. Unprecoated Basalt Aggregate
      • 3.2.2. Effect of Precoating on Initial Adhesion
      • 3.2.3. Comparison with the Data of Maccarrone
    • 3.3. Changes in Adhesion with Time
      • 3.3.1. Kinetic Measurements with Unprecoated Basalt Aggregate
      • 3.3.2. Kinetic Measurements with Precoated Basalt Aggregate
      • 3.3.3. Kinetic Measurement Result Summary
    • 3.4. Binder Adhesion Viscosities and Effects on Recommended Cutter Levels
  • 4. CONCLUSIONS
  • REFERENCES