<p>Accurate prediction of temperature fields in parallel wire cables—critical components like main cables, hangers, and stay cables in cable-supported bridges—is pivotal for their fire resistance assessment. However, existing studies predominantly focus on small-scale cables and rely on oversimplified homogeneous models that neglect internal cavities, undermining reliability for large-scale applications. Addressing this gap, this study investigates sectional heat transfer characteristics of large-diameter (100–340&#xa0;mm) parallel wire cables with explicit consideration of internal cavities. Temperature rise tests were conducted to capture wire temperature histories at different cross-sectional positions, followed by the development of a refined numerical model incorporating cavity structures, validated using experimental data. The effects of fire source models, cable porosity, and diameter on heat transfer were analyzed. Results show numerical-experimental discrepancies ≤ 35℃ within 60&#xa0;min and ≤ 10% thereafter, confirming model reliability. Internal cavities induce uneven temperature distributions, influenced by fire source, porosity, and diameter. HC fire causes peak temperatures of 1035℃ and gradients of 445℃, with the time to reach the peak values being 48&#xa0;min and 12&#xa0;min, respectively. That is, HC fire poses the greatest threat to cable components, and it is recommended as the fire source model for fire resistance analysis of cable components. Marked differences exist between homogeneous round steel and actual cables (357℃ in internal wire temperature, 402℃ in gradient), underscoring the necessity of cavity-aware modeling. The research provides reliable temperature rise data for evaluating fire-induced bearing capacity degradation and optimizing fire protection design of cable components.</p>

错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

Quantifying internal cavity effects on heat transfer in large-diameter parallel wire cables: tests and high-fidelity simulations

  • Bo Geng,
  • Wei Chen,
  • Ruili Shen,
  • Xinghua Chen,
  • Pei Yuan,
  • Zhi Zheng

摘要

Accurate prediction of temperature fields in parallel wire cables—critical components like main cables, hangers, and stay cables in cable-supported bridges—is pivotal for their fire resistance assessment. However, existing studies predominantly focus on small-scale cables and rely on oversimplified homogeneous models that neglect internal cavities, undermining reliability for large-scale applications. Addressing this gap, this study investigates sectional heat transfer characteristics of large-diameter (100–340 mm) parallel wire cables with explicit consideration of internal cavities. Temperature rise tests were conducted to capture wire temperature histories at different cross-sectional positions, followed by the development of a refined numerical model incorporating cavity structures, validated using experimental data. The effects of fire source models, cable porosity, and diameter on heat transfer were analyzed. Results show numerical-experimental discrepancies ≤ 35℃ within 60 min and ≤ 10% thereafter, confirming model reliability. Internal cavities induce uneven temperature distributions, influenced by fire source, porosity, and diameter. HC fire causes peak temperatures of 1035℃ and gradients of 445℃, with the time to reach the peak values being 48 min and 12 min, respectively. That is, HC fire poses the greatest threat to cable components, and it is recommended as the fire source model for fire resistance analysis of cable components. Marked differences exist between homogeneous round steel and actual cables (357℃ in internal wire temperature, 402℃ in gradient), underscoring the necessity of cavity-aware modeling. The research provides reliable temperature rise data for evaluating fire-induced bearing capacity degradation and optimizing fire protection design of cable components.