Analytical solution for crack growthing of semi-submersible platform’s horizontal brace
Abstract
The article present an analytical solution to calculate the crack growth characteristics of semi-submersible platform’s horizontal brace with a circumferential through–crack lies at the boundary between the horizontal brace and column loaded by tension. The results of the proposed model may be applied in the full range of fracture from stationary crack to plastic collapse and the solution process is clear and the closed form solution is found which is especially suitable to solve problems in practical engineering application. The relationship between tension and crack growth and the influence of different initial angles and material parameters of the horizontal brace to the crack initiation load and ultimate load have been got as well as the variation tendencies of crack tip opening displacement on the cracked section and the relationship between plastic zone and elastic zone of the cracked section with different tension under stationary crack condition in this article with a practical engineering application example which could give good suggestion to semi-submersible platform designers and managers.
The article present an analytical solution to calculate the crack growth characteristics of semi-submersible platform’s horizontal brace with a circumferential through–crack lies at the boundary between the horizontal brace and column loaded by tension. The results of the proposed model may be applied in the full range of fracture from stationary crack to plastic collapse and the solution process is clear and the closed form solution is found which is especially suitable to solve problems in practical engineering application. The relationship between tension and crack growth and the influence of different initial angles and material parameters of the horizontal brace to the crack initiation load and ultimate load have been got as well as the variation tendencies of crack tip opening displacement on the cracked section and the relationship between plastic zone and elastic zone of the cracked section with different tension under stationary crack condition in this article with a practical engineering application example which could give good suggestion to semi-submersible platform designers and managers.
The article present an analytical solution to calculate the crack growth characteristics of semi-submersible platform’s horizontal brace with a circumferential through–crack lies at the boundary between the horizontal brace and column loaded by tension. The results of the proposed model may be applied in the full range of fracture from stationary crack to plastic collapse and the solution process is clear and the closed form solution is found which is especially suitable to solve problems in practical engineering application. The relationship between tension and crack growth and the influence of different initial angles and material parameters of the horizontal brace to the crack initiation load and ultimate load have been got as well as the variation tendencies of crack tip opening displacement on the cracked section and the relationship between plastic zone and elastic zone of the cracked section with different tension under stationary crack condition in this article with a practical engineering application example which could give good suggestion to semi-submersible platform designers and managers.
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