LOCALIZATION ISSUES IN MODELLING OF SUBSTANDARD RC BEAM-COLUMN JOINTS
World Conference on Earthquake Engineering proceedings, International Association for Earthquake Engineering, 2024
- Yayın Türü: Kitapta Bölüm / Araştırma Kitabı
- Basım Tarihi: 2024
- Yayınevi: International Association for Earthquake Engineering
- Anahtar Kelimeler: Crack band theory, Cyclic analysis, Lattice modelling, OpenSees, Truss analogy
- Uşak Üniversitesi Adresli: Evet
Özet
Strain adjustment methods can be used in quasi-brittle materials to minimize the adverse effects of mesh size and localization in the numerical modelling of sub-standard beam-column joints. The nonlinear lattice modelling approach is adopted for this purpose. The lattice model is built using the truss analogy, in which the concrete and reinforcing elements of an RC beam-column joint are represented as truss elements. Furthermore, using zero-length springs efficiently captures the reinforcing bar slip relationship between the bars and concrete parts, which are in contact. The modelling approach is validated by comparing the simulated responses with the experimental data obtained from quasi-static cyclic loading tests conducted on two inadequately detailed sub-standard RC beam-column joints. To alleviate the issues arising from mesh size and localization, adjustments are made to the compressive strain at complete stress release in the linear softening branch, following the crack band approach. A comparison is made between the lattice model and a rigid joint model, which does not take the joint deformation into consideration. The use of the lattice modelling technique produces more realistic results by improving computing efficiency and decreasing computation time. The fidelity of the lattice modelling approach in reproducing the experimental response is deemed reasonably satisfactory.