*Article* **Force Analysis of Self-Anchored Suspension Bridges after Cable Clamp Slippage**

**Hongfeng Li \*, Yancheng Liu, Chunwei Li, Hao Hu and Quansheng Sun**

> School of Civil Engineering, Northeast Forestry University, Harbin 150040, China; yanchengliu@nefu.edu.cn (Y.L.); lichunwei@nefu.edu.cn (C.L.); huhao@nefu.edu.cn (H.H.); sunquansheng@nefu.edu.cn (Q.S.)

**\*** Correspondence: lihongfeng@nefu.edu.cn

**Abstract:** The slippage of cable clamps during the long-term operation of suspension bridges is a common and detrimental phenomenon. From an experimental point of view, the cable clamp slippage of a suspension bridge was investigated to reveal the effect of this sliding on the force acting on the full bridge. The forces acting on the bridge before and after the slippage were analyzed using a finite element model. The calculation results showed that the cable clamp slippage directly affects the cable forces of the hangers. The hanger cable force decreased by 19.2% when the slippage reached 10.2 cm, while the maximum increase in the cable force of adjacent hangers was 147.7 kN, an increase of 7.25%. The variation of forces in the hanger cable disrupted the force balance of the main girder, thereby producing a torque effect at the corresponding position in the girder, i.e., increased torque. Meanwhile, the slippage affected the axial tension in the main cable and the main girder. The impact of the tower internal force was less than 1%. Hence, the study concluded that the effect of cable clamp slippage is better understood, ensuring the safety of the suspension bridge.

**Keywords:** self-anchored suspension bridge; cable clamp; slippage; force analysis
