Optimal design of an arch bridge with high performance steel for bridges using genetic algorithm

In this work, we outline a methodology for determining optimal helical flagella placement and phase shift that maximize fluid pumping through a rectangular flow meter above a simulated bacterial carpet. This method uses a Genetic Algorithm (GA) combined with a gradient-based method, the Broyden-Fletcher-Goldfarb-Shanno (BFGS) algorithm, to solve the optimization problem and the Method of Regularized Stokeslets (MRS) to simulate the fluid flow. This method is able to produce placements and phase shifts for small carpets and could be adapted for implementation in larger carpets and various fluid tasks. Our results show that given identical helices, optimal pumping configurations are influenced by the size of the flow meter. We also show that intuitive designs, such as uniform placement, do not always lead to a high-performance carpet.

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BETHLEHEM LUKENS PLATE HPS-70W

Alloy Digest ◽

10.31399/asm.ad.sa0506 ◽

2000 ◽

Vol 49 (12) ◽

Keyword(s):

Fracture Toughness ◽

Corrosion Resistance ◽

Tensile Properties ◽

High Performance ◽

Iron And Steel ◽

Cooperative Agreement ◽

Federal Highway ◽

High Performance Steel ◽

Department Of The Navy ◽

Steel Institute

Abstract BETHLEHEM LUKENS PLATE HPS-70W is a high-performance steel (HPS) developed through a cooperative agreement among the Federal Highway Administration (FHWA), the American Iron and Steel Institute (AISI), and the Department of the Navy. This steel is an improved version of ASTM A 709 grade 70W. This datasheet provides information on composition and tensile properties as well as fracture toughness. It also includes information on corrosion resistance as well as forming and joining. Filing Code: SA-506. Producer or source: Bethlehem Lukens Plate.

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Experimental study on fatigue performance of Q420qD high-performance steel cross joint in complex environment

Asian Journal of Civil Engineering ◽

10.1007/s42107-021-00351-6 ◽

2021 ◽

Author(s):

Haigen Cheng ◽

Cong Hu ◽

Yong Jiang

Keyword(s):

Fatigue Life ◽

High Performance ◽

Steel Structure ◽

Steel Structures ◽

Fatigue Tests ◽

Fatigue Performance ◽

Corrosive Media ◽

Joint Connection ◽

High Performance Steel ◽

The Cross

AbstractThe steel structure under the action of alternating load for a long time is prone to fatigue failure and affects the safety of the engineering structure. For steel structures in complex environments such as corrosive media and fires, the remaining fatigue life is more difficult to predict theoretically. To this end, the article carried out fatigue tests on Q420qD high-performance steel cross joints under three different working conditions, established a 95% survival rate $$S{ - }N$$ S - N curves, and analyzed the effects of corrosive media and high fire temperatures on its fatigue performance. And refer to the current specifications to evaluate its fatigue performance. The results show that the fatigue performance of the cross joint connection is reduced under the influence of corrosive medium, and the fatigue performance of the cross joint connection is improved under the high temperature of fire. When the number of cycles is more than 200,000 times, the design curves of EN code, GBJ code, and GB code can better predict the fatigue life of cross joints without treatment, only corrosion treatment, and corrosion and fire treatment, and all have sufficient safety reserve.

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