USE OF COLD IN-PLACE RECYCLED ASPHALT MIXES FOR ROAD SURFACES . 5TH CONFERENCE ON ASPHALT PAVEMENTS FOR SOUTHERN AFRICA (CAPSA 89). PROCEEDINGS HELD IN SWAZILAND, 5-9 JUNE, 1989

Currently, the United States is experiencing a national trend toward rehabilitation of distressed asphalt concrete (AC) pavements as opposed to new construction. This, compounded by the inflationary trend in the cost of construction materials, is requiring highway agencies to pursue alternative approaches to the preservation of existing highway systems. One approach, which is proving to be one of the most promising and cost-effective alternatives, is cold in-place recycling (CIR). Advantages attributed to the use of cold in-place recycling include significant cost savings realized through savings in energy, conservation of costly construction materials, and a reduction in the impact on the environment, as well as the ability to limit mitigation to the distressed lane. Although significant savings are realized through the use of CIR, there remains an absence of proven and simple mix and thickness design procedures - standard design procedures currently do not exist. Furthermore, due to the lack of long-term performance data and adequately documented field engineering studies, many agencies remain skeptical of the use of CIR as a viable alternative to pavement restoration and rehabilitation. However, several major research efforts are currently underway to summarize current and/or develop new technical data associated with cold in-place recycling. These efforts are expected to address the need that exists for realistic and defensible procedures for the design and use of CIR asphalt pavements. One of the major efforts researching cold in-place recycling was a joint study between the Oregon Department of Transportation (ODOT) and Oregon State University (OSU). This study was initiated in April 1986 and completed in June 1988 with the overall objective to develop a simple and reliable mix design procedure for cold in-place recycled pavements in the state of Oregon. This paper summarizes the efforts undertaken by ODOT and OSU to accomplish this objective. Specifically, this paper presents: (1) A review of the projects that were studied. These encompass nearly 322 km (200 miles) of cold in-place recycled AC pavements constructed during the period of 1984 to 1986; (2) The process used to construct the pavements. CIR was accomplished employing two different methods: a "recycling train" and a "single unit" machine; (3) The performance of the cold in-place recycled pavements. Field and laboratory data were collected and evaluated in order to assess the performance of the pavements as well as to investigate the effects of emulsion content, curing time, and compactive effort. Field performance evaluations indicate the pavements are performing very well. Laboratory test results indicate the mix properties differ only slightly from those of conventional mixes; and (4) Recommendations for a simple and reliable mix design procedure for cold in-place recycled asphalt materials as well as improved guidelines and specifications for the

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  • Corporate Authors:

    CAPSA

    PO BOX 993
    Manzini,   Swaziland 
  • Authors:
    • Hicks, R G
    • Scholz, T
    • ALLEN, D
  • Publication Date: 1989

Language

  • English

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Filing Info

  • Accession Number: 00604059
  • Record Type: Publication
  • Source Agency: Transport and Road Research Laboratory (TRRL)
  • ISBN: 0-620-14395-9
  • Files: ITRD, TRIS
  • Created Date: Feb 28 1991 12:00AM