Anti-slip friction resistance of main cable′s pin-connected and straddle-type clamps in suspension bridges: Analytical models and FEM validation

Abstract

Cable clamps in suspension bridges are critical connecting components that transfer the loads from the hangers to the main cable. These clamps are typically secured to the main cable by bolt pre-tensioning force, relying on friction to resist slippage. Although current design standards provide formulas for calculating the anti-slip capacity of cable clamps, they often rely on overly simplistic assumptions. The lack of rigorous, quantitative mechanical derivations in these formulas yields approximate results and introduces significant calculation errors. This study comprehensively considers key factors such as friction coefficient and hanger tension, addressing the fundamental complexity of the clamp-main cable contact interaction. Focusing specifically on pin-connected and straddle-type cable clamps, this study considers the friction distribution at the clamp-cable interface and the geometry of straddle hangers. Separate analytical models are developed for each clamp type, revealing the clamp’s stress state and accurately estimating the load-bearing capacity against slippage. The accuracy of the analytical models was validated through the finite element method (FEM). The proposed analytical method offers clear theoretical principles and straightforward calculations. It provides a precise means of estimating the frictional resistance of cable clamps to slippage, offering a reliable and economical reference for the anti-slip design of cable clamps.