12 resultados para Slurry bubble column
em Iowa Publications Online (IPO) - State Library, State of Iowa (Iowa), United States
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Stratigraphic Column of Iowa
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Extensive programmed laboratory tests involving some 400 asphalt emulsion slurry seals (AESS) were conducted. Thirteen aggregates including nine Iowa sources, a quartzite, a synthetic aggregate (Haydite), a limestone stone from Nebraska, and a Chat aggregate from Kansas were tested in combination with four emulsions and two mineral fillers, resulting in a total of 40 material combinations. A number of meetings were held with the Iowa DOT engineers and 12 state highway departments that have had successful slurry seal experiences and records, and several slurry seal contractors and material and equipment suppliers were contacted. Asphalt emulsion slurry seal development, uses, characteristics, tests, and design methods were thoroughly reviewed in conjunction with Iowa's experiences through these meetings and discussions and through a literature search (covering some 140 articles and 12 state highway department specifications). It was found that, while asphalt emulsion slurry seals (when properly designed and constructed) can economically improve the quality and extend the life of existing pavement surface, experiences with them had been mixed due to the many material, slurry, and construction variables that affect their design, construction, and performance. The report discusses those variables identified during the course of the project and makes recommendations concerning design procedures, design criteria, specifications and the means of evaluating them.
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As part of the overall research program of evaluating asphalt emulsion slurry seal as a pavement maintenance material, 31 duplicate 500-ft test sections were constructed on U.S. 6 between Adel and Waukee in Dallas County during September and October of 1978. These test sections included combinations of eight aggregates, two gradings, three asphalt emulsions, two mineral fillers, and a range of emulsion contents determined by laboratory mix designs. The emulsion contents of the test sections varied from 10.3% for Section 7A (Ferguson coarse) to 32.9% for Section 31A (lightweight aggregate). The post-construction performance evaluation of the test sections, consisting primarily of the friction tests and surface appearance observations, was conducted at different time intervals up to 24 months after construction. At the 24-month final evaluation, most of the test sections had carried a total of 1.4 million vehicles.
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This is a monthly column prepared by the Iowa Public Information Board to update Iowans on the IPIB’s activities and provide information on some of the issues routinely addressed by the board.
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This is a monthly column prepared by the Iowa Public Information Board to update Iowans on the IPIB’s activities and provide information on some of the issues routinely addressed by the board.
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This is a monthly column prepared by the Iowa Public Information Board to update Iowans on the IPIB’s activities and provide information on some of the issues routinely addressed by the board.
Resumo:
This is a monthly column prepared by the Iowa Public Information Board to update Iowans on the IPIB’s activities and provide information on some of the issues routinely addressed by the board.
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This is a monthly column prepared by the Iowa Public Information Board to update Iowans on the IPIB’s activities and provide information on some of the issues routinely addressed by the board.
Resumo:
This is a monthly column prepared by the Iowa Public Information Board to update Iowans on the IPIB’s activities and provide information on some of the issues routinely addressed by the board.
Resumo:
This is a monthly column prepared by the Iowa Public Information Board to update Iowans on the IPIB’s activities and provide information on some of the issues routinely addressed by the board.
Resumo:
This is a monthly column prepared by the Iowa Public Information Board to update Iowans on the IPIB’s activities and provide information on some of the issues routinely addressed by the board.
Resumo:
This is a monthly column prepared by the Iowa Public Information Board to update Iowans on the IPIB’s activities and provide information on some of the issues routinely addressed by the board.