ULTIMATE STRENGTH EVALUATION AND DYNAMIC VERTICAL RESPONSE OF ROOF TYPE SINGLE LAYER LATTICE SHELLS INDUCED BY GABLE WALLS OF GYMNASIA SUBJECTED TO HORIZONTAL EARTHQUAKE MOTIONS

In this study, FE modeling method for the buckling/ultimate strength analysis of a continuous stiffened panel under combined shear and thrust is proposed. In order to validate the proposed method, shear buckling collapse tests of a stiffened panel and FEM analysis are carried out. As the result of these, it is confirmed that the buckling collapse behavior and the ultimate strength estimated by the proposed method are in good agreement with the test results.

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Numerical and Experimental Research on the Ultimate Strength for a Stiffened Titanium Cylinder

Volume 11B: Honoring Symposium for Professor Carlos Guedes Soares on Marine Technology and Ocean Engineering ◽

10.1115/omae2018-78663 ◽

2018 ◽

Author(s):

Siming Yuan ◽

Qiang Chen

Keyword(s):

Ultimate Strength ◽

Research Work ◽

High Strength ◽

Simulation Method ◽

Influential Factors ◽

Material Nonlinearity ◽

Cylinder Pressure ◽

Scaled Model ◽

Strength Evaluation ◽

Strength Assessment

Titanium alloys are widely used in naval ships due to its high strength, low density, no magnetism, corrosion resistance and so on. However, the material nonlinearity brings new challenges to the ultimate strength evaluation on the Titanium structure. This work is to evaluate the ultimate strength for a stiffened titanium cylinder with consideration of material nonlinearity by numerical analysis and scaled model experiment. Firstly, a series of titanium alloy stiffened cylinder pressure hulls are analyzed for their ultimate strength by non-linear Finite Element Method (FEM). Secondly, model tests are carried out for the above titanium cylinders to obtain their ultimate carrying capacity. Thirdly, the good agreement between experiment and numerical results verify that the numerical simulation method is suitable for ultimate strength evaluation. Finally, some influential factors on the ultimate capacity of the stiffened titanium cylinder are investigated, including stiffeners arrangement, thickness of cylinder hulls, inside diameter. The research work can map the limitations of the current rules and to support the development of ultimate strength assessment guidelines for titanium cylinder pressure hulls.

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Study on Dynamic Strength Evaluation Method of Mechanical Members Based on Energy Balance

Volume 8: Seismic Engineering ◽

10.1115/pvp2007-26525 ◽

2007 ◽

Author(s):

Keisuke Minagawa ◽

Satoshi Fujita ◽

Seiji Kitamura ◽

Shigeki Okamura

Keyword(s):

Energy Balance ◽

Experimental Model ◽

Ultimate Strength ◽

Nuclear Power ◽

Power Plants ◽

Nuclear Power Plants ◽

Dynamic Strength ◽

Input Energy ◽

Seismic Safety ◽

Strength Evaluation

This paper describes the dynamic strength evaluation of piping installed in nuclear power plants from a viewpoint of energy balance. Mechanical structures installed in nuclear power plants such as piping and equipment are usually designed statically in elastic region. Although these mechanical structures have sufficient seismic safety margin, comprehending the ultimate strength is very important in order to improve the seismic safety reliability in unexpected severe earthquakes. In this study, ultimate strength of a simple single-degree-of-freedom model is investigated from a viewpoint of energy balance equation that is one of valid methods for structural calculation. The investigation is implemented by forced vibration experiment. In the experiment, colored random wave having predominant frequency that is similar to natural frequency of the experimental model is input. Stainless steel and carbon steel are selected as material of experimental model. Excitation is continued until the experimental model is damaged, and is carried out with various input levels. As a result of the experiment, it is confirmed that input energy for failure increase with an increase of time for failure. Additionally it is confirmed that input energy for failure depend on the material.

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