原文传递 Experimental Assessment of Aggregate Surfacing Materials.
题名: Experimental Assessment of Aggregate Surfacing Materials.
作者: mokwa, r. trimble, n. cuelho, e.
关键词: base course, permeability, laboratory tests, crushed top surfacing, roads, montana, strength, stiffness, construction materials, pavements, surface drainage, compaction
摘要: An extensive suite of geotechnical laboratory tests were conducted to quantify differences in engineering properties of three crushed aggregates commonly used on Montana highway projects. The material types are identified in the Montana Supplemental Specifications as CBC-6A, CBC-5A, and CTS-2A. Results from R-value tests and direct shear tests performed on large samples (12 in by 12 in) indicates the CBC-6A aggregates generally exhibited the highest strength and stiffness of the three material types. In terms of strength parameters, there was no statistically significant difference between CBC-5A and CTS-2A materials. The CBC-6A and 5A materials exhibited similar average Rvalues, which were both slightly greater than the CTS-2A materials. Overall, the CTS-2A materials generally exhibited the lowest average strength and stiffness. Although this material was the poorest performer when compared to the two CBC materials, it still exhibited relatively high strength and stiffness. Drainage capacity was quantified by conducting multiple saturated constant head permeability tests on 10-inch-diameter samples of each material type. The CBC-6A and CTS-2A materials had the highest average permeability values, while the CBC-5A materials had the lowest. Permeability was shown to depend more on the fine fraction void ratio (ef) than on aggregate type or maximum particle size. An analytical method of predicting permeability based on ef was developed, which will allow MDT designers to estimate permeability based on gradation and state of compaction. Overall, the CBC-6A materials were generally the best performers in this study. / NOTE: Final rept. Jan 06-Jun 07. / Supplementary Notes: Sponsored by Federal Highway Administration, Helena, MT. Montana Div. and Montana Dept. of Transportation, Helena. Research Program. / Availability Note: Order this product from NTIS by: phone at 1-800-553-NTIS (U.S. customers); (703)605-6000 (other countries); fax at (703)605-6900; and email at orders@ntis.gov. NTIS is located at 5285 Port Royal Road, Springfield, VA, 22161, USA.
总页数: u0723;77p
报告类型: 科技报告
检索历史
应用推荐