PSI - Issue 60

Anupoju Rajeev et al. / Procedia Structural Integrity 60 (2024) 222–232 Author name / StructuralIntegrity Procedia 00 (2019) 000–000

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member, fixed at one end and free at the other. The shock loading is applied to the column at its mid-height to closely simulate real-world structural loads. The shock loading is applied as a uniform shock pressure of 300 kPa on the column at its mid-height, as this configuration closely simulates the realistic loads encountered by structural members. The shock wave pressure profile is characterized by a short-duration delta pulse lasting 100 ms. The structure under investigation comprises a sturdy beam with a length of 1300mm and a cross-section of (300mm x 300mm). The column's height is 1.2 m, and its dimensions are (75mm x 75mm). These dimensions have been selected to represent a 1/4th scale of a real-world column. Additional information regarding scaling is explicitly discussed in the preceding work [3–5].

Fig. 1. Detailing of reinforcement provided in RC section

In this analysis, the RC column is constructed with concrete having a peak compressive strength of 17 MPa. The material's strain rate due to loading is detected using spectral imaging through a high-speed camera, with all experiments conducted at an approximate strain rate of 1 s -1 . The stress-strain curve for M17 grade concrete in both tension and compression is generated using Mander et al. [16] while degradation data is obtained through Equations 3 and 4. The time-variant shock loading is characterized by different impulse values and is represented as a concentrated load at the mid-height of the column section. The reinforcement steel is composed of Fe 410 bars with an elastic modulus of 200 GPa and a Poisson's ratio of 0.3. Steel and concrete densities are assumed to be 7850 kg/m³ and 2500 kg/m³, respectively, while the Poisson's ratio of concrete is set at 0.2. The bond between the reinforcement bars and the concrete block is established using an embedded region constraint in Abaqus, ensuring the ideal bonding criteria between concrete and steel. The base of the concrete beam is fixed, constraining all six degrees of freedom.