Vibration of skew plates by using B-spline functions

This paper deals with the free vibration of skew plates by the Rayleigh-Ritz method with B-spline functions as co-ordinate functions. Convergence of the solutions is investigated in a few typical cases and is found to be satisfactory. The accuracy of the results is compared with the existing results based on other numerical methods and found to be in good agreement.     

Analysis of skew plate problems with various constraints

This paper presents the application of the modified Rayleigh-Ritz method with Lagrange multipliers to analyze skew plate problems with various constraints. By this procedure one can satisfy both geometric and natural boundary conditions of skew plates. To demonstrate the accuracy and versatility of the method, several examples of bending, vibration and buckling of skew plates are solved, and results are compared with those obtained by other approximate methods.     

Present state of experimental stress analysis by strain gages in Japan

This paper describes the present state of strain gages, measuring devices and stress-cycle counters in Japan. Details are given to the following items: (1) electric-resistance-wire strain gages, (2) vibrating-string gages, (3) magnetostriction gages, and (4) stress-cycle counters. Items (1) and (2) manufactured in Japan are comparable to those manufactured in other advanced countries. Item (3) was specially developed in Japan. Research on item (4) is now in progress.This Field Report is based on a paper presented, by title only, at the 1960 SESA Spring Meeting held in Indianapolis, Ind., on May 18–20.     

A study on the period of the free lateral vibration of the beam bridge by the theory of the orthotropic rectangular plate

Conclusion The frequency of the right, simple beam bridges is discussed by the laboratory study on the model beam bridges and the field tests on existing beam bridges in this paper, but furthermore, the application to the skew beam bridge or to the continuous beam bridge and the problem of forced vibration should be studied.Even if more exact studies are necessary, it is made sure by the study in this paper that the theory of the orthotropic plate is proper to the analysis of the free lateral vibration of the beam bridge and sufficient enough for practical purpose, especially for the beam bridge of which the width is almost equal to the span.     

A model for structural safety using the extreme value approach

A new method of evaluating the safety of a structure using the maximum mean largest value concept is introduced. The paper is characterized by the following points: The maximum probability of failure is defined by employing the upper bound of load and the lower bound of resistance, that is, the structural safety is evaluated under the worst-state both for load and resistance. This is a distribution-free approach to the concept of structural safety, and the probability of failure is calculated without assuming the probability density distributions of load and resistance. Three new characteristics are introduced so that the character of the data is strongly reflected on the estimation of the maximum probability of failure. A numerical example is given using the test data.     

A Simple Method for Synthesizing Ultra-high-molecular-weight Polystyrene through Emulsion Polymerization Using Alkyl-9-BBN as an Initiator

Styrene emulsion polymerization using an alkyl-9-BBN, synthesized by reacting 9-BBN(9-borabicyclo-[3.3.1]-nonane) and styrene, in an aqueous sodium dodecyl sulfate(SDS) solution was studied. Ultra-high-molecular-weight( 1.0 × 10~7) polystyrene was synthesized using a radical initiator formed through the aerobic oxidation of this alkyl-9-BBN in a high yield( 80%). The kinetics of this emulsion polymerization of styrene with the alkyl-9-BBN was investigated. We confirmed that in the initial stage of the polymerization, the initial reaction rate followed first-order kinetics. The activation energy for this emulsion polymerization of styrene was approximately 56.2 kJ/mol.