Hole Angle Repair The Elastic Analysis And Design Of Circular Castellated Beams

Castellated steel beams can save amount of materials and facilitate passage of pipes, high capacity being of practical value for engineering application. However, castellated beams are not classical members which accord with Bernoulli's assumption of section remaining plane. Their design remains unsatisfactorily solved. There is no technical standard for castellated beams in China. Therefore, it is necessary to further study. The castellated beams with rounded rectangular holes can avoid stress concentration of the hexagon castellated beams and the loss of the expansion ratio of the circular castellated beams. The main content is as follows:1. The basic principle of the substructure analysis is introduced, and the substructure analysis technique is use to calculate various cases of openings for improving the computational efficiency. The maximum stress and the ratio of the deflection to the span of the castellated beams under the distributed linear load is Separately got when it is simplely supported. Create tables to facilitate the design of the castellated beams. The method to use the data tables for designing with a calculated example is illuminated.2. According to the results of finite element analysis (FEA) of castellated beams with rounded rectangular holes under pure bending to determine the equivalent flexural stiffness. It is simple, accurate, economical, and high efficient. A rational formulation is presented to calculate the equivalent flexural stiffness of the castellated beams with rectangular holes, in which the reduction coefficient of stiffness for web with openings is obtained by FEA and expressed by a half-empirical equation for web with oval holes.3. On the basis of Vierendeel analogy to open web truss, the expression of deflection is derived for the castellated beams with rectangular holes beams. Then it is used to evaluate the deflection of the castellated beams with rectangular holes and the relevant parameters are given by correlation to the FEA results. 4. The value of the relevant stiffness of the castellated beams with the rounded rectangular for buckling analysis is determined, and the critical moments based on the corresponded formulas of the full-web beams is obtained, at the same time FEA is carried out. The results of these formulae and the FEA are verified by good coincidence. The feasibility to get the critical moment of the castellated beams with rectangular holes by using the corresponded formulae of the full-web beams and the value of stiffness in this paper is verified.