Fatigue tests of under-strenghth timber railroad bridge stringers.

As the ability to obtain high-grade material becomes more difficult, assessing the value of under-strength timber for use in maintaining timber railroad bridges has become increasingly important. The objective of this study was to examine, experimentally, the fatigue behavior of under-strength timb...

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Bibliographic Details
Main Author: Borchers, Christopher Ryan
Format: Thesis eBook
Language:English
Published: [Place of publication not identified] : [publisher not identified] ; 2002.
Subjects:
Online Access:Link to OAKTrust copy
Description
Summary:As the ability to obtain high-grade material becomes more difficult, assessing the value of under-strength timber for use in maintaining timber railroad bridges has become increasingly important. The objective of this study was to examine, experimentally, the fatigue behavior of under-strength timber railroad bridge stringers. The sample group that was tested included nineteen southern pine solid-sawn stringers that were 178 mm (7 in.) wide by 356 mm (14 in.) deep by 4.8 m (16 ft) long. The commercial grade of the members ranged from below No. 3 to No. 2. All of the members had been pressure treated "to refusal" with creosote. Results from the fatigue tests indicate a substantial variation in the fatigue strength of the members; the slope of the normalized S-N diagram was nearly zero. A natural fatigue limit appeared to be approximately 50-60 percent of estimated fiber bending strength. The failure modes observed were predominantly horizontal shear and tension.
Item Description:"Major subject:Civil Engineering".
Bibliography also included in Appendix I: leaves 58-66.
Vita.
Physical Description:ix, 67 leaves : illustrations ; 28 cm.
Also available online.
Issued also on microfiche from Lange Micrographics.
Bibliography:Includes bibliographical references (leaf 57).