مقاله انگلیسی رایگان در مورد پاسخ لرزه ای سازه های پل با ستون های قطعه ای – الزویر 2018

To achieve the accelerated bridge construction (ABC), precast segmental columns are more and more widely used in engineering applications recently. Comparing with the conventional cast-inplace monolithic columns, precast segmental bridge columns have many obvious advantages such as the high quality control of fabrication, minimum environmental impact and smaller residual displacement after a severe earthquake [1,2]. Despite these apparent advantages, the constructions of bridges with segmental columns were normally limited in low seismic intensity regions. The application of this bridge type in regions with high seismicity is rare due to the lack of understanding on their seismic performances. Recently extensive research works have been carried out to investigate the seismic behaviors of precast segmental columns. Hewes and Priestley [3] conducted analytical and experimental investigations on the seismic performances of unbonded posttensioned precast concrete segmental columns with high and low aspect ratios. It was found that unbonded pre-stressed segmental columns could effectively resist the lateral earthquake loading. However, limited energy was dissipated by the segmental columns. To improve the energy dissipation capability of segmental columns, many different energy dissipation devices have been proposed by different researchers. Chang et al. [4] and Ou et al. [5] advocated the use of continuous mild steel bars, which are also named as ED bars, along the pier segments to improve the energy dissipation capacity. A flag-shape hysteretic behavior with increased energy dissipation capacity was observed in the experimental studies. Experimental results revealed that small residual displacement upon unloading could be obtained if the ED bar ratio is below a certain threshold. Except for ED bars, researches on the external energy dissipaters also have been conducted. Chou and Chen [6] suggested using concrete-filled tubes as external energy dissipaters, and their results showed that the equivalent viscous damping ratio can be obviously increased. Marriott et al. [7] used two different external replaceable energy dissipaters for unbonded pre-stressed segmental piers and obtained considerable energy dissipation when compared with the traditional hybrid ED bar system. Some previous studies (e.g. [8–10]) showed that monolithic connections between first segment and the footing can result in better energy dissipation than segmental connections under seismic loading. The use of other energy dissipaters were also reported including external steel angles and rubber pads [8] and built-in elastomer pad [9]. Besides using dissipaters, improving the material performance of components, such as using high performance ED bars [10] or ductile fiber-reinforced concrete [11], could lead to higher drift capacity, greater energy dissipation, and higher lateral strength of the column.