A Study on Application of Strain Indices for Seismic Performance Verification to Real-Scale RC Member by 3D Nonlinear FEA

EasyChair Preprint 5759

Abstract

The applicability of seismic performance verification indices based on the strain index calculated by three-dimensional material nonlinear finite element analysis was verified for real-scale RC members subjected to bilateral loadings. The verification was conducted by using three strain indices: main tensile strain (ε_t), main compressive strain (| ε_c |), and main shear strain (| ε_sh |). The average strain in the elements was used for each index. In addition, the second strain invariant of deviatoric strain tensor (√J’₂) and consumed strain energy (W_n), which are assumed to be less affected by element size, were also examined. The areas verified in all the members and in the core concrete.

As a result, all the indices reached the limit state before the maximum load capacity because they reached the limit value in cover concrete when all the elements were set as the area to be verified. In other words, it is possible to make a rational evaluation linked to a physical phenomenon, which is a reduction of shear load capacity due to the fracture of the core concrete, when the verification is conducted only in core concrete.  √J’₂ and W_n were conservatively evaluated compared with other strain indices.  ε_t, | ε_c | and | ε_sh |, which are easily affected by element size, could be reasonably evaluated within this study. The reason is that large-scale members naturally have large element dimensions, making it difficult for large strain to be generated locally. Furthermore, it was clarified that all verification indices reached the limit values while maintaining sufficient load capacity in all the RC members with post-installed shear reinforcement, horizontal two-directional loadings, or initial damage in the orthogonal direction.

Keyphrases: FEA, real-scale RC member, seismic performance verification indices, two directional loadings

@booklet{EasyChair:5759,
  author    = {Satoshi Komatsu and Yoshinori Miyagawa and Toyofumi Matsuo},
  title     = {A Study on Application of Strain Indices for Seismic Performance Verification to Real-Scale RC Member by 3D Nonlinear FEA},
  howpublished = {EasyChair Preprint 5759},
  year      = {EasyChair, 2021}}