Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)

Department / School

Civil Engineering


This thesis concerns the investigation of single button welded lap joints utilized to join two specimens of structural steel. More specifically, it reports on the static load-carrying capabilities of this type joint. The objectives of this study are: (1) to study the button welds produced by carbon0dioxide shielded metal arc welding equipment, (2) to determine the static strength of characteristics of button welds, (3) to determine whether these welds can be considered statistically reliable for structural applications. Research, in line with these objectives, was conducted in connection with the effect of the various electrical controls of the equipment on the weld strength. Essentially, this included a series of shear tests with all joints being made at 208 volts input to the equipment utilizing ¼ inch thick material. Two other series of tests with 230 volts input were also conducted utilizing 3/16 inch and ¼ inch thick material. Riveted joints in like material were tested for comparison with the button welded joints. Tension tests on the button welds comprised another series. Several joints were sawed transversely, polished, and etched. Photomicrographs were taken, with Rockwell hardness tests being made on the weld cross section. From the test data, it is apparent that button welds can be made considerable consistency and that the feasibility of button welded joints in structural steel is a possibility.

Library of Congress Subject Headings



Includes bibliographical references



Number of Pages



South Dakota State University