PSI - Issue 66

Jiaqi Li et al. / Procedia Structural Integrity 66 (2024) 221–228

222

2

Author name / Structural Integrity Procedia 00 (2025) 000–000

one of the main causes of frame structure failure. Therefore, ensuring sufficient seismic performance of joints is an important goal of seismic design. Due to its excellent hysteresis performance, low yield point steel has been increasingly used as a new type of seismic energy dissipation material in structural seismic design, such as for steel plate shear walls, buckling-restrained braces, energy dissipating dampers, etc. [4-6]. Based on the excellent energy dissipation performance of low yield point steel, energy dissipation devices made of low yield point steel can be connected to beam-column joints to achieve seismic energy dissipation. CL composite dowels have been proven to possess good load-bearing capacity and sufficient deformation ability even in high-strength concrete, which can replace head stud for connecting steel and concrete sections [7-12]. In addition, previous experiments have shown that CL composite dowels have good shear and tensile fatigue performance [13-14]. Based on the above reasons, a new energy dissipation joint is proposed in this paper, which utilizes the good connection and fatigue performance of CL composite dowels and the good ductility and hysteresis performance of low yield point steel to achieve seismic energy dissipation of the joint. In this paper, numerical simulations are conducted to study and compare the seismic performance of the new energy dissipation joint with that of ordinary beam-column joints, and the influence of low yield point steel strength on the seismic performance of the new energy dissipation joint is investigated.

Nomenclature CL composite dowel

Clothoid composite dowel

Elastic modulus Poisson's ratio

E

ν

Standard value of axial compressive strength of concrete Standard value of axial tensile strength of concrete

f ck f tk f y f u ε u

yield strength Ultimate strength

Strain corresponding to f u

2. Conceptual design of the energy dissipation joints bases on CL composite dowels The new energy dissipation joint proposed in this paper is shown in Fig. 1. This new energy dissipation joint consists of the reinforced concrete beam, column and the energy dissipation device with CL composite dowels. The material of this energy dissipation device is low yield point steel, welded from the perforated steel plate and its side stiffeners, which is connected to the concrete beam through the CL composite dowels at the lower part of the perforated plate, and to the concrete column through the CL composite dowels at the upper part of the stiffeners. The detailed connection type is shown in Fig. 2. Under static load, the bearing capacity of the joint is mainly provided by reinforced concrete. Under dynamic load, the energy dissipation device can effectively weaken the seismic response of the joint by dissipating energy through the yield of low yield point steel. Here are advantages of the new energy dissipation joint:  The energy dissipation device is connected to the reinforced concrete beam and column through CL composite dowels. CL composite dowels have good shear and tensile mechanical properties, which can effectively connect the energy dissipation device to the beam and column, enabling the energy dissipation device to deform together with the beam-column joint to achieve yield energy dissipation. In addition, CL composite dowels have good fatigue performance and can function well under cyclic load, effectively avoiding damage to the connection between the energy dissipation device and beam-column joint.  In the energy dissipation device, the steel plate is weakened by opening holes, making the opening area a weak point, effectively avoiding damage to the connection area and ensuring the reliability of the energy dissipation device under cyclic load. At the same time, stiffeners are welded on the side of the perforated