PSI - Issue 78

Agnese Natali et al. / Procedia Structural Integrity 78 (2026) 2015–2021

2017

2.2. Test Setup and Instrumentation

The experimental test was carried out under monotonic horizontal loading applied to the top of the CHS column. The base of the column was pinned to a rigid substructure, and the beam ends were restrained using tie rods. Two hydraulic actuators with a maximum capacity of 450 kN were used in parallel to impose lateral displacement. A sketch of the test setup is shown in Fig. 2, which also indicates the position of the loading cells.

Fig. 2. Test Setup representation and Loading Cells distribution.

Instrumentation included LVDTs positioned at the actuators, beam ends, and near the joint region to monitor displacements and relative slips. Strain gauges were applied to the flanges of the beams (Fig.3) and reinforcement bars within the slab. Additionally, a Digital Image Correlation (DIC) system was used to capture the full-field strain distribution on the nodal zone, enabling a more detailed understanding of deformation patterns and weld crack initiation.

Fig. 3. Strain gauges configuration on IPE beams with respect to top column displacement.

3. Experimental Results The specimen was pulled until the actuator displacement capacity was reached, showing a force-displacement behaviour as illustrated in Fig.4. Although not essential for monotonic loading, an unloading cycle was performed