Fig 1.
Comparison between the boundary beam and conventional transfer girder systems.
(a) Conventional transfer girder system. (b) Newly proposed boundary beam-wall system.
Fig 2.
Typical shape and reinforcement details of the boundary beam-wall system.
(a) Front view. (b) Back view.
Fig 3.
Specimen identification.
Fig 4.
Details of the reference specimen (B50-T125-S125).
(Unit: mm).
Fig 5.
Boundary beam section details of the test specimens.
(Unit: mm). (a) B50-T100-S125. (b) The other three specimens.
Fig 6.
Wall section details of the test specimens.
(Unit: mm). (a) Upper wall. (b) Lower wall of specimen B50-T125-S125. (c) Lower wall of specimen B40-T125-S125. (d) Lower wall of specimen B50-T100-S125. (e) Lower wall of specimen B50-T125-S75.
Table 1.
Summary of test specimens.
Table 2.
Concrete material properties.
Table 3.
Rebar material properties.
Fig 7.
Test setup.
Fig 8.
Strain gauge setup.
Fig 9.
Typical failure shape (Reference specimen B50-T125-S125).
(a) Front view. (b) Side view.
Fig 10.
Lower wall failure shape of specimen B50-T125-S125.
(a) Overall view. (b) Left lower wall. (c) Right lower wall.
Fig 11.
Lower wall failure shape of specimen B40-T125-S125.
(a) Overall view. (b) Left lower wall. (c) Right lower wall.
Fig 12.
Lower wall failure shape of specimen B50-T100-S125.
(a) Overall view. (b) Left lower wall. (c) Right lower wall.
Fig 13.
Lower failure shape of specimen B50-T125-S75.
(a) Overall view. (b) Left lower wall. (c) Right lower wall.
Fig 14.
Load-displacement curves of the test specimens (LVDT-1).
Table 4.
Test results.
Fig 15.
Load-displacement curves of the test specimens (LVDT-2, LVDT-3).
Fig 16.
Concrete strain distribution at the upper wall (C1~C3).
(a) Specimen B50-T125-S125. (b) Specimen B40-T125-S125. (c) Specimen B50-T100-S125. (d) Specimen B50-T125-S75.
Fig 17.
Concrete strain distribution near the end of the boundary beam (C4~C6).
(a) Specimen B50-T125-S125. (b) Specimen B40-T125-S125. (c) Specimen B50-T100-S125. (d) Specimen B50-T125-S75.
Fig 18.
Concrete strain distribution at the lower wall (C10~C14).
(a) Specimen B50-T125-S125. (b) Specimen B40-T125-S125. (c) Specimen B50-T100-S125. (d) Specimen B50-T125-S75.
Fig 19.
Main bar strain distribution at the top of the lower wall (S7~S10).
(a) Specimen B50-T125-S125. (b) Specimen B40-T125-S125. (c) Specimen B50-T100-S125. (d) Specimen B50-T125-S75.
Fig 20.
Stirrup strain distribution at the top of the lower wall (S11~S13).
(a) Specimen B50-T125-S125. (b) Specimen B50-T125-S75.
Fig 21.
Load transfer path of each specimen.
Fig 22.
Stress-strain curves of concrete.
(a) Compressive behavior. (b) Tensile behavior.
Fig 23.
Finite element mesh adopted in this study.
(a) Concrete. (b) Rebars.
Fig 24.
Boundary conditions of the finite element model.
Fig 25.
Finite element meshes used for sensitivity analysis.
(a) Three different meshes used for sensitivity analysis. (b) Reference model.
Fig 26.
Relative errors in displacement of the three models with respect to nDOFs.
Table 5.
Results of the mesh sensitivity analysis.
Fig 27.
Comparison between the load-displacement curves by the test and FE analysis.
(a) Specimen B50-T125-S125. (b) Specimen B40-T125-S125. (c) Specimen B50-T100-S125. (d) Specimen B50-T125-S75.
Table 6.
Initial stiffness and peak strength of each specimen by the test and FE analysis.
Table 7.
Relative ratio of the peak strength of each specimen to that of the reference specimen.
Fig 28.
Von Mises stress distribution at peak load (Reference specimen B50-T125-S125, stress unit: MPa).
Fig 29.
Von Mises stress and DAMAGEC distributions of the lower wall concrete at several different loading stages (Reference specimen B50-T125-S125).
(a) Von Mises stress distribution. (Stress unit: MPa). (b) DAMAGEC distribution.
Fig 30.
Von Mises stress and plastic strain distributions of the lower wall rebars at several different loading stages (Reference specimen B50-T125-S125).
(a) Von Mises stress distribution. (Stress unit: MPa). (b) Plastic strain distribution.
Fig 31.
S22 stress distribution near the top of the lower wall.
(Stress unit: MPa). (a) Specimen B50-T125-S125. (b) Specimen B40-T125-S125. (c) Specimen B50-T100-S125. (d) Specimen B50-T125-S75.