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This paper investigates the moment modification factors of an I-girder with trapezoidal web corrugations under moment gradient and various end restraint conditions. The moment modification factors are obtained by using the finite element method with beam elements and new general formulas of cross-section properties as well as a new warping constant of the I-girder with trapezoidal web corrugations. The theoretical results of moment modification factors are successfully verified by comparing them with the results from the commercial finite element software using shell elements. A series of finite element analyses with different corrugation profiles and lengths are investigated. From the results, it is found that the present design of moment modification factor formulas cannot satisfactorily predict the buckling capacities of the I-girder with trapezoidal web corrugations under unequal end moments with various end restraint conditions. For the purpose of design, the closed-form expressions for the moment modification factors are proposed and successfully verified.

Background Vaccination is very important for the control and prevention of influenza, yet no vaccine is perfectly safe. Little is known, however, about influenza vaccination-associated serious adverse events following immunization (AEFI). This study aimed to identify background information on influenza vaccination-related serious AEFI in Korea. Methods Retrospective review of data from Korea National Vaccine Injury Compensation Program from 2003 to 2010. Results Distribution of approximately 75 million doses of influenza vaccine by end of 2010 gave rise to 42 potentially serious AEFI. In all, nine Guillain-Barre syndrome, eighteen other neurologic events, eight local events, and seven miscellaneous events were included. 62% of these events were identified to have unlike causal association with the vaccine. The reporting rate of serious AEFI ranged from 0.006 to 0.07 cases per 100,000 distributed doses of the vaccine. Conclusion GBS was the most common influenza vaccination-related serious AEFI. Enhancing post-vaccination GBS surveillance may increase public confidence in future routine and pandemic influenza vaccination.

While I-girders with trapezoidal web corrugations have been used in various structural applications and bridges, lateral torsion–flexure of I-girders with trapezoidal web corrugations still needs to be investigated, especially the general formulation for cross-section properties. This paper presents the results of theoretical and finite element analyses of the lateral-torsional buckling of an I-girder with trapezoidal web corrugations under uniform moment. By using the numerical equations and method, the location of shear center and warping constant are proposed. The elastic lateral-torsional buckling strength is then calculated via proposed cross-section properties. The results are compared with previous studies in the literature. A series of finite element analyses with different corrugation profiles and lengths are investigated and the results are compared with proposed formulas. Through comparative numerical studies, the proposed formulas are successfully verified. The effects of corrugation profiles on elastic lateral-torsional buckling strength are also investigated and discussed.