With High Strength Steel To Improve The Seismic Performance Of Rectangular Piers Experimental Study

To the present, most experiment researches and earthquake damage indicate that most structures enter elasto-plasticity condition in the strong motion earthquake. The bridge construction displays elasto-plasticity deforming which is nonlinear deformation most concentrating in piers, structural shock-resistant performance is directly related to the ductility and power-wasting ability of piers. Therefore, it has important theoretical and practical significance to the study on the seismic behavior of the piers. The subject of'Experimental investigation of adopting high strength steels to improve the seismic performance of the rectangular piers'which is subsidize-financed by the Beijing Municipal Education Commission Fund, proposed the seismic behavior experiment of the concrete bridge piers which are configured high strength steels. It provides the basis of emending our country's earthquake-resistance designing codes and the applying of the high strength steels in theory and experiment.According to the pseudo static tests on earthquake-resistance ability of the six concrete rectangular bridge piers model, which are subjected to the vertical loads and the horizontal cyclic loads, in this paper the factors of impacting the ductility and energy dissipation of the specimens are studied in detail. The strength of the steel bar, the layout of the high strength steel and the general, the axial compressive ratio, the aspect ratio and the stirrup ratio are also specially studied. Discussing the characteristics of the hysteresis curves, skeleton curves, and steel strain curves, then we can abtain the displacement ductility ratios and the energy dissipation ratios of the pier models. At last, an empirical formula about displacement ductility ratios is put forward.Through the analysis of the configured high strength steel bars concrete bridge pier specimen models' test results, we reach some important conclusions, the ductility of high strength concrete bridge pier is related to the axial compressive ratio, the type and layout of longitudinal reinforcement, the stirrup ratio, and so on; It can do to improve the ductility of bridge piers when we use the high strength steels as stirrups; Parts of longitudinal reinforcements use high strength steel bars can improve the ductility of the bridge piers, but too many high-strength steels should not be configured. Known by the conclusions, the purpose of this subject'Because of the elasticity of the high-strenth steel and the general are similar but the strength of high strength steel is higher than the general, using this characteristic of the material, parts of longitudinal reinforcement and stirrups instead by high strength steel bars can do to improve the deformation of the bridge piers which under strong earthquake damage.' can smooth up.