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ITEM 4REVIEW OF PREVIOUS REPORTS
G. H. Harris, Chairman;
H. L. Ripley,
The Sub-Committee after reviewing much of the previous work of the Committee and attempting to reduce it to a form for presentation, discovered that the result would be nothing more than an index. In view of the fact that there is now an index in book form for all matter prior to 1915; that each year's proceedings contains a complete index and that if an index were now prepared and published as part of the 1922 report it would be no more available after the lapse of a year or so than the indices in the individual volumes, the recommendation is made that the subject be dropped.
O. E. SELBY, Chairman;
P. B. MOTLEY, Vice-Chairman;
To the American Railway Engineering Association:
The Committee on Iron and Steel Structures respectfully presents herewith its annual report to the Association.
Subject No. 1. Revision of Manual In the General Specifications for Steel Railway Bridges, 1920, three changes are recommended. The Committee is reluctant to make changes in these specifications which have been adopted so recently and received so favorably, but these few changes will correct inconsistencies and supply an obvious omission. They should be adopted now and promulgated pending a more extended revision of the Specifications which may be needed after the lapse of five or ten years. The changes are of such a nature that the Specifications still may bear the date of 1920 and existing copies may be corrected by the use of pasters or otherwise.
Following are the changes recommended for adoption and printing in the Manual :
Article 47—Change the last sentence to read: “The unit stresses specified in Article 38 may be increased one-third for a combination of the secondary stresses with the other stresses, but the section shall not be less than that required when secondary stresses are not considered.”
Article 48-Change to read: “The gross area of the compression flanges of plate girders and rolled beams shall not be less than the gross area of the tension flanges, but the stress per square inch shall not exceed
b 1 = the length of the unsupported fange between lateral connections
or knee braces. b = the flange width.”
Article 243—Omit all of the fourth sentence after the word “Engineer," making the Article read: Eye-Bars.
243. Eye-bars shall be straight, true to size, and free from twists, folds in the neck or head, and other defects. The heads shall be made by upsetting, rolling or forging. Welding will not be allowed. The form of the heads will be determined by the dies in use at the works where the eye-bars are made, if satisfactory to the Engineer. The thickness of the head and neck shall not overrun more than 1-inch for bars 8 inches or less in width, 18-inch for bars more than 8 inches and not more than 12 inches in width, and 1-inch for bars more than 12 inches wide.
Subject No. 2. Specifications for the Erection of Steel Railway
Bridges The Specifications, Appendix A, are submitted as information. They are the result of careful and extended consideration by the Committee and may be worthy of adoption as a conclusion at this time, but following the practice of the Committee with respect to other important specifications in the past it is desired that they may appear in bulletin form for a year so that we may get the benefit of a trial and discussion by users.
Subject No. 3. Specifications for Movable Railway Bridges
The Specfications, Appendix B, are submitted as a conclusion for printing in the Manual. The statement in the Foreword gives the history of their development. The Committee believes them to be the best specifications for movable bridges available now; and while, from the nature of the subject and the rapidly changing status of the art, they cannot be without faults, their approval and promulgation should not be delayed.
Subject No. 4. Classification of Bridges Subject No. 5. Specifications for Turntables and Turntable Pits
Subject No. 6. Specifications for Steel Highway Bridges
These three subjects are in the hands of active sub-committees and will be made the principal work of the Committee for next year.
Subject No. 7. Column Tests Subject No. 8. Electric Welding of Connections in Steel Structures The Committee recommends the continuation of these two subjects.
Subject No. 9. Rules for Lighting Drawbridges Subject No. 10. Regulations and Signals for Operation of Drawbridges
The Committee reports progress on these two new subjects and recommends that they be consolidated and reassigned.