Cyclic and static behaviors of CFT modular bridge pier with enhanced bracings

  • Kim, Dongwook (Department of Civil Engineering, Chung Ang University) ;
  • Jeon, Chiho (Department of Civil Engineering, Chung Ang University) ;
  • Shim, Changsu (Department of Civil Engineering, Chung Ang University)
  • Received : 2015.11.11
  • Accepted : 2016.02.11
  • Published : 2016.04.30


Modular structures consist of standardized modules and their connections. A modular bridge pier is proposed to accelerate bridge construction. Multiple concrete-filled steel tubes (CFTs) using commercial steel tubes were chosen as the main members. Buckling restrained bracings and enhanced connection details were designed to prevent premature low-cycle fatigue failure upon cyclic loading. The pier had a height of 7.95 m, widths of 2.5 m and 2.0 m along the strong and weak axis, respectively. Cyclic tests were performed on the modular pier to investigate structural performance. Test results showed that four CFT columns reached yielding without a premature failure of the bracing connections. The ultimate capacity of the modular pier was reasonably estimated based on the plastic-hinge-analysis concept. The modular CFT pier with enhanced bracing showed improved displacement ductility without premature failure at the welding joints.


Supported by : Ministry of Land, Transportation and Maritime Affairs(MLTM)


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