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This paper focuses on the elasto -plastic behavior of static and dynamic responses for single layer lattice domes, which are subjected to vertical loads. The purpose is to make clear the relationship between seismic responses and static responses from the view point of input strain energy properties after and before yielding, and to estimate bearable seismic levels with the information of static elastoplastic behaviors. The static response compared is the relationships between equivalent velocities of strain energies and displacements.The dynamic response compared is that between earthquake input acceleration PGA and equivalent velocities of strain energies. This paper focuses on the elasto -plastic behavior of static and dynamic responses for single layer lattice domes, which are subjected to vertical loads. The purpose is to make clear the relationship between seismic responses and static responses from the view point of input strain energy properties after and before yielding, and to estimate bearable seismic levels with the information of static elastoplastic behaviors. The static response compared is the relationships between equivalent velocities of strain energies and displacements.The dynamic response compared is that between earthquake input acceleration PGA and equivalent velocities of strain energies.

Reinforced concrete (RC) buildings in Peru use low ductility walls, with rectangular cross-sections and reinforced with wire mesh and vertical reinforcement bars at boundary ends, as structural elements. These structural elements have no columns, have small amounts of reinforcing bars and are expected to fail in a brittle manner. In this study, a performance verification test is conducted on the use of carbon fiber sheets (CFS) as a retrofitting method for shear walls without boundary columns. The focus is on retrofitting walls that fail in flexural mode. In other words, although an increase in strength cannot be expected, CFS retrofitting can delay the concrete crushing of the shear wall base that occurs during flexural failure; and the aim is to verify this improvement in deformation performance due to CFS retrofitting. From the test, by retrofitting the RC shear wall without boundary columns with CFS, it was found that postmaximum strength deterioration was more gradual, and deformation performance was improved. And Ultimate limit deformation of specimen which was partially retrofitted at the boundary ends of the wall was larger than that of specimen which was retrofitted over the entire wall span.

Stress transferring mechanisms of exterior wide-beam to column joints using headed beam bars with transverse beams were examined by FEM analysis. The characteristics of the stress transferring mechanisms obtained from the FEM analysis are summarized as follows: (1) in a inner region where a beam is directly connected to columns, the shear force is transferred by concrete compressive struts formed by flexural compressions in the critical sections of the columns and the beam and the bearing forces of the headed bars, (2) in outer regions where the beam is connected to the transverse beams, the torsional moment acting on the transverse beam affects the formation of concrete compressive struts, and (3) the tensile forces in beam reinforcements arranged in the outer regions become smaller than those in the inner region.

In this paper, two dimensional non-linear finite element (FE) analyses for RC shear walls with multi-openings were conducted to investigate the shear force contributions and internal stress transferring mechanisms. Parametric analyses were also conducted for the shear walls with several opening layouts. The analytical results showed that diagonally compressive struts transferring shear forces were formed in each wall element and the shape depended on the wall panel length, regardless of opening layouts and loading directions. On the basis of these analytical results, the simplified shear resistant model of the shear walls with multi-openings was constructed. It is clarified that the shear strength of RC shear walls with multi-openings can be evaluated by the proposed simplified model.