Size Effects of High Strength Steel Wires

Abstract

This study examines the effects of size on the strength of materials, especially on high strength pearlitic steel wires. These wires play a central role in many long span suspension bridges and their design, construction, and maintenance are important for global public safety. In particular, two relationships have been considered to represent strength variation with respect to length parameters: (i) the strength versus inverse square-root and (ii) inverse length equations. In this study, existing data for the strength of high strength pearlitic steel wires is evaluated for the coefficient of determination (R2 values). It is concluded that the data fits into two equations equally well. Thus, the choice between two groups of theories that predict respective relationships must rely on the merit of theoretical developments and assumptions made.

A Simple Estimation Method of Weibull Modulus and Verification with Strength Data

“…Percy's article [41] reported UK test results in the 1880s. The strength reached a level of 1 GPa, but the m value was still 13.7 [15,44]. At about the same time, wires for the Brooklyn Bridge (finished in 1883) had the strength of 1.1 GPa.…”

“…Over the next 20 years, steel technology improved further and provided 1.5-GPa steel wires for the Williamsburg Bridge in New York (finished in 1903). Perry [42] provided 160 test data for the cable wires that were removed during the rehabilitation work in the 1980s, and Weibull analysis was conducted [15,44], yielding m = 16 with an average tensile strength of 1.5 GPa. The values are remarkable after more than 80 years of use, since these wires did not have galvanizing protection against corrosion.…”

“…h. High strength suspension cable wires [15] Two datasets of high C steel strength, one from the Bisan Seto Bridge in Japan with N = 38,470 (completed in 1988), showed m values of 94 to 97, with the strength levels reaching 1.65-1.66 GPa.…”

“…where Γ(x) is the gamma function. This Equation (2) can be approximated by [15]: <σ> = σ o (1 + 0.276 m −0.776 ).…”

Crystal Strengths at Micro- and Nano-Scale Dimensions

“…The research relates to reference [20] in which a comparison was made between the experiment and simulation of nano-indentations in (111) and (100) α-iron crystal surfaces. At an opposite dimensional scale, an important civil engineering connection spanning nano-to macro-size dimensions was provided by a comparison of the ultrafine steel wire measurements described for the drawn micro-wire strengths presented in Figure 2 and the comprehensive description by Ono [39] of steel wire materials employed in historical and current transportation bridge constructions.…”