It is the purpose of this paper to discuss in detail unusually precise structural model design, construction, and test procedure.
A statement of the laws of similarity to which all structural models must conform if precise results are to be obtained in the simplest manner is given by Mr. Loudenslager. Scale selection, choice of materials, and construction methods are all considered by him.
Three model members of designs which can represent a number of prototype properties are described in detail, as well as the use of each of these members, and the determination of bending, torsional, tensile, and compressive stresses by means of simple equipment. In addition, design formulas are set forth for a member which represents the axial, torsional, and bending (in two planes) properties.
Finally, three test procedures, all applicable to a variety of simple or complicated indeterminate structures, and the methods used in evaluating the test results are presented by the author.
Briefly, these are: tests in which influence lines are photographed so that axial and bending stresses in redundant structures can be determined; stability tests for determining buckling strength; and tests to give bending and other stresses.
