Emulsified asphalt has been widely used in various surface treatment methods such as chip seal for low-volume road preservation. Using modified emulsified asphalt made it possible to use chip seal technology on medium- and even high-volume traffic pavements. The main objective of the study is to quantify the residue characteristics of rubber-modified emulsified asphalt and to assess the effectiveness of using crumb rubber to modify emulsified asphalt binder. The four emulsified asphalt residues used the distillation procedure. Then, the rheology characteristics of emulsified asphalt residue were evaluated. The Fourier transform infrared spectroscopy (FTIR) test analyzed the chemical change of emulsified asphalt during the aging procedure. The results indicate that the evaporation method cannot remove all the water in emulsified asphalt. The mass change during the rolling thin film oven (RTFO) process only represented the component change of emulsified asphalt binder residue. Both the high-temperature and low-temperature performance grade of the two emulsified asphalt binders with rubber were lower. The original asphalt binder adopted to emulsification had a crucial influence on the performance of emulsified asphalt. The rubber modification enhanced the property of the emulsified asphalt binder at low temperatures, and the improvement effect was enhanced as the rubber content in the emulsified asphalt was raised. The C=O band was more effective in quantifying the aging condition of the residue. The findings of this study may further advance the emulsified asphalt technology in pavement construction and maintenance.

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Laboratory Evaluation of the Residue of Rubber-Modified Emulsified Asphalt

Effect of laboratory-produced cellulose nanofiber as an additive on performance of asphalt binders and mixes

A chip seal is a very effective thin surface treatment process used by maintenance managers to preserve existing asphalt pavements. The Kansas Department of Transportation (KDOT) 2014 Chip Seal Manual is a guide that provides guidelines, background and general information for the design, construction, and inspection of chip seals. This manual is intended for use by KDOT field engineers, laboratory personnel, construction inspectors, and contractor’s estimators, supervisors, operators, and workers to provide procedures for the design of chip seals. The information, recommendations and best practices provided in this manual may refer to either: (1) learning the overall chip seal operation; (2) learning about the workings, maintenance, calibration and proper operation of equipment used in chip sealing; or (3) learning chip seal design procedures. This manual consists of seven chapters. Chapter 1 is the introduction. Chapter 2 is about selection of chip seal. Chapter 3 discusses the materials for chip seal and the design process. Chapter 4 discusses surface preparation prior to chip sealing. Chapter 5 describes equipment inspection and calibration. Chapter 6 discusses the actual application process. Chapter 7 underlines the areas of concern during construction process.

Kansas Department of Transportation 2014 chip seal manual : [technical summary].

Effective Modeling of Extended Service Life for Pavement Treatments

The purpose of the Monroe Chip Seal Case Study was to evaluate chip seal performance for multiple test sections comprised with different asphalt emulsion – aggregate type combinations with emphasis on aggregate retention, especially during winter months. Different emulsions and aggregates were desired to be evaluated to determine if there was an optimum combination for performance in this climate over the course of one winter. Specific comparisons of interest in this project included: (1.) Neat (non-oil) emulsions versus emulsions with low oil additives, ( 2.) Modified emulsions with latex styrene butadiene rubber (SBR) versus modified emulsions with styrene butadiene styrene (SBS) and ( 3.) Limestone aggregate retention versus crushed gravel aggregate retention. Aggregate retention was measured through imaging analysis. Photographs were taken at identical locations monthly between September 2009 and April 2010. The change in aggregate coverage was measured over time by converting the photographs into black and white binary images. The binary images allowed for the calculation of aggregate coverage. Major findings of the research include that adding 1.0% #2 fuel oil to an anionic high float emulsion improved performance (aggregate retention) over emulsions without oil. Anionic limestone chip seals outperformed anionic gravel chip seals. No appreciable difference between limestone and gravel cationic chip seals was observed. There was no significant difference between latex modified and tyrene butadiene styrene (SBS) modified chip seals for gravel seals. Limestone seals with latex modified emulsion performed slightly better than SBS modified chip seals.

The Monroe, Michigan Chip Seal Case Study: An Evaluation of Multiple Chip Seals’ Cold Weather Field Performance

Effects of emulsion types, application rates, and crumb rubber on the laboratory performance of chip seal

The aim of this study was to characterize the chemical, molecular, and rheological properties of different asphalt emulsions including a newly introduced tire-rubber modified asphalt emulsion (CRS-...

Rheological and Molecular Characterizations of Tire Rubber Modified Asphalt Emulsion

Chip sealing is a commonly used pavement maintenance technique that aims to delay pavement deterioration by reducing water infiltration and restoring skid resistance. The objective of this study wa...

Short-Term Field Performance and Cost-Effectiveness of Crumb-Rubber Modified Asphalt Emulsion in Chip Seal Applications:

An experimental study was conducted to evaluate the rheological and molecular characterization of rubberized asphalt emulsion. One rubberized asphalt emulsion and an asphalt rubber (CRS-2TR and AC20-TR) and two conventional emulsions (CRS-2 and CRS-2P) were evaluated. The emulsions were characterized by conducting rheological and physical testing. The influence of adding crumb rubber on the binder chemical composition was investigated in the laboratory using Fourier Transform Infrared Analysis (FTIR) on the original, Rolling-Thin Film Oven (RTFO) and Pressure Aging Vessel (PAV)-aged binder residues. Results showed that CRS-2TR and AC20-TR had lower carbonyl and sulfoxide indices indicating better resistance to aging compared to conventional asphalt emulsions. Results of High-Pressure Gel Permeation Chromatography (HP-GPC) on the original, RTFO and PAV-aged binder residues showed that CRS-2TR and AC20-TR had similar High-Molecular Weight (HMW) content compared to that of conventional asphalt emulsions indicating similar susceptibility to brittleness with age.

/pdf/rheological-and-molecular-characterization-of-rubberized-cxtm86wqn7.pdf

Rheological and Molecular Characterization of Rubberized Asphalt Emulsion

Chip sealing is a widely popular pavement maintenance treatment because of its low initial cost and convenient construction process. Bleeding, loss of aggregate, reduced skid resistance, and aging have been identified as the most common type of distress that lead to the failure of chip sealing. The objective of this study was to evaluate the laboratory performance of a crumb-rubber-modified asphalt emulsion and a high-float polymer-modified asphalt emulsion in chip sealing and to evaluate the effects of crumb rubber as a modifier as well as its utilization as part of the aggregate stone. To achieve this objective, four types of emulsion were evaluated, namely a crumb-rubber-modified asphalt emulsion (CRS-2TR), a high-float polymer-modified emulsion (CHFRS-2P), a polymer-modified emulsion (CRS-2P), and a conventional unmodified emulsion (CRS-2). Based on the results of the experimental program, it was concluded that the aggregate retention properties of polymer-modified and crumb-rubber emulsions were superior to the unmodified emulsion. In addition, the granite aggregate performed better than the granite–crumb-rubber blends regardless of the type of emulsion used. However, a small percentage of crumb rubber may be used in chip sealing without significantly affecting its performance. According to the rheological and physical test results, CHFRS-2P showed the highest useful temperature interval (92.7), followed by CRS-2P (87.8), CRS-2TR (82.6), and CRS-2 (76.7). Based on Fourier transform infrared spectroscopy and saturate, aromatic, resin, and asphaltene test results, both CRS-2TR and CHFRS-2P showed lower carbonyl indices growth as compared to the other emulsions, indicating superior resistance to aging.

Tanvir Ahmed Sarkar

Papers

Effects of emulsion types, application rates, and crumb rubber on the laboratory performance of chip seal

Rheological and Molecular Characterizations of Tire Rubber Modified Asphalt Emulsion

Short-Term Field Performance and Cost-Effectiveness of Crumb-Rubber Modified Asphalt Emulsion in Chip Seal Applications:

Rheological and Molecular Characterization of Rubberized Asphalt Emulsion

Investigating the Laboratory Performance of Crumb-Rubber-Modified and High-Float Polymer-Modified Asphalt Emulsions in Chip Sealing