Full Description

Preface

The purpose of this monograph is to provide in one source a summary and analysis of reliable data on the fatigue behavior of welded structural members and joints. Most of the data are presented in chart and tabular form.

There are still many engineers who are not thoroughly acquainted with the problems of fatigue. Therefore, the first part of this book is devoted to a rather brief elementary discussion of the engineering aspects of fatigue and the factors that affect it.

The influence of weld defects upon fatigue strength is discussed at a number of points in this book. The question of how to evaluate such defects in general and how to avoid them and make corrections will naturally occur to some readers. Accordingly, at the suggestion of several interested parties, a discussion of weld defects, their causes and methods of correction are briefly discussed in Chapter 5.

Following this general discussion, information and data from many laboratory tests of welded structural members and connections are presented along with an analysis of these data. These laboratory studies have been carried out by numerous investigators, on a variety of materials, with a multitude of different types of specimens, and using various types of testing machines. The effects of many variables have been studied.

The basic fatigue data used for the analyses are presented in the tables of this book. Anyone wishing to extend further his study of various test results may do so by referring to the original data from which these basic data were derived. Complete files of original data are available in the Structural Library of the Civil Engineering Department, University of Illinois, Urbana, 111., and in the Engineering Societies Library in New York, N. Y. Most of this monograph is based upon research and studies that are reported in the tables and the various references of the bibliography.

It is hoped that the data, discussions and recommendations in this monograph, along with the analyses of the data, will provide a better background for the proper design of structures subjected to repeated loads.

The information presented in this monograph was assembled through the efforts of a number of people. Messrs. J. R. Fuller, E. McEwen, and R. Schmidt tabulated much of the data, and Mr. McEwen, under the direction of Professor J. E. Stallmeyer, assembled the initial analyses for certain of the connections. The members of the Fatigue Committee of the Welding Research Council have served as a review committee and offered many helpful suggestions during the preparation of the manuscript. Without the assistance of these persons a volume of this type and scope would have been beyond question.

The author and editor would also like to acknowledge the important effect that three former members of the Fatigue Committee have had on the development of this volume. It was the foresight and research of Professor W. M. Wilson* that led the way to much of the fatigue information that has been developed in the United States. The strong leadership and technical contributions of Mr. Jonathan Jones,* who for a number of years served as chairman of the Fatigue Committee, and the wise counsel and guidance of Mr. W. S. Spraragen, who for many years directed the activities of the Welding Research Council, were responsible for the initiation of the studies that have led to this volume.