Physical modelling of reinforced concrete at a 1:40 scale using additively manufactured reinforcement cages

Abstract

Global level assumptions of numerical models have received relatively less attention, but have been indicated to be a major source of error in numerical modeling of Reinforced Concrete (RC) structures. In parallel, it has been stated that a statistical approach involving many virgin specimens and ground motions is necessary for model validation. Such an approach would require very small‐scale testing. Then, the reinforcement fabrication becomes a major issue. This paper proposes using additive manufacturing to fabricate the reinforcement cage. It presents the results from cyclic tests on 1:40 RC cantilever members. The cages were manufactured using an SLM 3D printer able to print rebars with submillimeter diameters. Different longitudinal and transverse reinforcement configurations were tested. A numerical model using existing Opensees elements was built and its parameters were calibrated against material level small‐scale tests. It captured the cyclic response of the RC members with a reasonable accuracy. The cyclic behavior of the RC members resembles the behavior of full‐scale RC members indicating that such small‐scale specimens can be used for the statistical validation of the global level assumptions of numerical models.

Seismic response of slender MDOF structures with self‐centering base shear and moment mechanisms

“…Following the motion‐by‐motion comparison, the numerical and experimental results of the shaking table dataset were revisited with a focus on the statistical comparison of the Cumulative Distribution Function (CDF) of key response parameters that were discussed previously. The concept of statistical validation using the CDF plots has been applied to modelling of rocking structures that showed predictable rocking responses in the statistical sense 30–32 , 35–38 . Figure 5 presents the CDF plots used for the statistical comparison in this section.…”

“…The concept of statistical validation using the CDF plots has been applied to modelling of rocking structures that showed predictable rocking responses in the statistical sense. [30][31][32][35][36][37][38] Figure 5 presents the CDF plots used for the statistical comparison in this section. The numerical and experimental CDF plots were compared based on the Kolmogorov-Smirnov (K-S) distance 39,40 (i.e., the maximum vertical distance between the experimental and numerical CDF plots) and the relative errors (𝜀, defined as the absolute error between the experimental and numerical values divided by the experimental value) at the maximum horizontal distance, as well as at median and 90 th percentile of the experimental CDF plots, as listed in Table 1, and within each plot of Figure 5.…”

Effect of ground motion processing and filtering on the response of rocking structures

“…In fact, this approach is consistent with the fundamental seismic design problem, which involves computing the response to a set of ground motions, rather than to an individual one. [95][96][97][98][99][100][101][102][103] For an ensemble of ground motions to be useful, in this paper all ground motions were scaled to the same PGV. PGV was used as an intensity measure, as it performs better than PGA or PGD for rocking structures.…”

Finite element modeling of free‐standing cylindrical columns under seismic excitation

“…The tests were repeatable and predictable both with FEM 81 and with DEM 82 . Notably, the concept of statistical validation could also be applied to Masonry and Reinforced Concrete structures 83,84 . Reggiani Manzo et al.…”

“…82 Notably, the concept of statistical validation could also be applied to Masonry and Reinforced Concrete structures. 83,84 Reggiani Manzo et al showed 23 that the response of a rocking structure made of precast RC elements was also predictable in the statistical sense.…”