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Processing and Performance
出版U.S. Department of Agriculture, Forest Service, Forest Products Laboratory, 1979
URLhttp://books.google.com.hk/books?id=B8kFogEACAAJ&hl=&source=gbs_api
註釋Crossties were made by the Press-Lam process, in which logs are peeled into veneers, dried, and glued into billets in a continuous procedure. Billets were made from 8.5-foot-long veneers and from 4-foot-long veneers, cut into final product dimensions, and treated with preservative. In laboratory tests, bending strength and stiffness of the Press-Lam ties were found to exceed those of solid-sawn red oak crossties; shear strength was only adequate. Tie wear tests showed low surface wear for laminated ties, comparable to the performance of solid specimens. Results of spike driving tests, however, indicated problems in some species. All Press-Lam ties met the performance criteria in the cyclic delamination tests, and, in lateral resistance tests, Press-Lam ties were not significantly different from solid-sawn ties. Volume yields are discussed and cost estimates are provided for use in calculating total tie costs for specific cases.