Evaluation of Otta Seal Surfacing for Low-Volume Roads in Iowa - TR-674

(2018) Evaluation of Otta Seal Surfacing for Low-Volume Roads in Iowa - TR-674. Transportation, Department of

TR-674_ Tech Brief_Otta_seals_for_low-vol_rds_t2.pdf

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TR-674_Final Report_Otta_seals_for_low-vol_rds_w_cvr.pdf

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Low-volume roads represent a significant proportion of transportation infrastructure, and the cost of maintaining low-volume roads is quite high for secondary road departments. Traditional bituminous surface treatments (BSTS) for asphalt pavements require high-quality materials and specialized expertise, but Otta seal surfaces can be constructed using more economical local aggregates and regularly available equipment. To evaluate the feasibility of Otta seals as an alternative surface treatment on Iowa’s low-volume roads and gauge the cost-effectiveness and performance of Otta seals compared to BSTs, the first Otta seal construction project in Iowa was conducted using a double-layer Otta seal over a 6.4 km (4 mi) long existing asphalt pavement with cracks in Cherokee County during September 2017. This study focused on the general background of this construction project, the Otta seal design details, the Otta seal construction procedures, and the many investigative tests conducted before, during, and after construction. Multiple in situ investigations, including loose aggregate tests, dustometer tests, roughness tests, and visual appearance inspections, were conducted over different construction periods to evaluate the performance of this Otta seal constructed in Iowa. Economic analyses using Minnesota and Iowa as case study locations indicate that Otta seals could be more cost-effective than BSTs (i.e., than chip seals).

Item Type: Departmental Report
Note: Visit www.intrans.iastate.edu for color pdfs of this and other research reports.
Keywords: Aggregate, Asphalt, Bituminous Surface Treatment, Economic Analysis, Field Demonstration, Low-Volume Road, Otta Seal
Subjects: Transportation > Pavements
Transportation > Materials
Transportation > Maintenance and preservation
ID Code: 27882
Deposited By: Iowa DOT Research
Deposited On: 09 Jul 2018 17:35
Last Modified: 09 Jul 2018 17:35
URI: https://publications.iowa.gov/id/eprint/27882