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Based on the incremental dynamic analysis (IDA) method, this paper conducts seismic fragility analysis of a CFST plane frame, a CFST spatial frame under 1D (one-dimensional) ground motions, and a CFST spatial frame under 2D (two-dimensional) ground motions, with different attacking angles. Firstly, nine-story, three-span CFST frame structures (including the plane frame and spatial frame) were modeled in OpenSees, based on the accurate simulation of the hysteresis performance of the test CFST frames. Then, twenty-five groups of ground motions were employed to analyze the seismic response. Lastly, the IDA curve clusters, probabilistic demand models, and seismic fragility curves of frame structures were researched, respectively. The analytical results showed that the exceeding probability of the spatial frame under 2D ground motions was successively greater than that under 1D ground motions, and greater than the plane frame, and the maximum difference at each performance level was up to 6% and 16%, respectively. The fragility analysis result of the spatial frame was sensitive to the attacking angle of ground motion, and the exceeding probability of the 135°, 150°, and 165° fragility curves was larger than that of the 0° (original attacking angle) fragility curve at each performance level. The research results provide a reference for seismic fragility analysis of CFST frame structures employing the IDA method. [ABSTRACT FROM AUTHOR]

Frame piers of double-deck viaducts (DVFP) have been widely studied and applied due to their high levels of space utilisation and significant engineering benefits, but the uncertainty of their information on modelling significantly affects the accuracy of calculation results for structural seismic demand and seismic capacity, which leads to challenges regarding the accuracy and reliability of seismic fragility analysis. In this paper, an accurate non-linear finite element model of DVFPs was established based on the OpenSees open platform. The seismic fragility analysis of DVFPs is carried out by introducing the endurance time method, and the tornado diagram and central point methods were performed to investigate the sensitivity and uncertainty of a seismic fragility of DVFPs to nine modelling parameters, respectively. The results show that the logarithmic standard deviation of fragility when slight damage, moderate damage, significant damage, and collapse occur on DVFP after considering modelling uncertainty will increase by 6.4%, 16.1%, 13.3%, and 20.1%, respectively. Therefore, it is necessary to consider the influence of modelling uncertainty in seismic fragility analysis. [ABSTRACT FROM AUTHOR]

In order to investigate the effects of steel fiber, polyvinyl alcohol (PVA) fiber and mineral powder contnet on permeability resistance of steel-PVA hybrid fiber high performance concrete (HFHPC). The orthogonal experiment was designed to conduct the permeability resistance test of steel-PVA HFHPC, and the test results were analyzed through range analysis, variance analysis and regression analysis. The results show that the influence degree on the impermeability of HFHPC is steel fiber, mineral powder and PVA fiber from high to low. In the range of test level, the optimal horizontal combination of impermeability of concrete specimens is as follows: steel fiber volume fraction of 1.0%, PVA fiber volume fraction of 0.7% and slag powder mass replacement rate 20% . When the steel fiber volume fraction exceeds 1.0%, the impermeability of HFHPC decreases slightly, but it is still higher than that of standard plain concrete. Finally, multiple regression analysis is used to establish the prediction model of HFHPC permeability and steel fiber, PVA fiber and mineral powder. [ABSTRACT FROM AUTHOR]

Based on the corridor channel curtain wall reconstruction project at Wuhan Tianhe airport T2-T3 terminal building, the structural system of point supported glass curtain wall with cable structure 18 years ago was analyzed, the technical difficulties of curtain wall glass panel removal and bearing cable removal were studied, and technical measures for the dismantlement and reconstruction of point supported glass curtain wall with cable structure were reasonably proposed. During the construction process of the dismantlement and reconstruction, the curtain wall structure was dynamically monitored, the deformation of the monitoring points were small, and the construction process was in a safe state. Due to the success in the dismantlement and reconstruction control technology of the point supported glass curtain wall with cable structure in this project, it not only ensured the construction safety, but also improved the construction quality, which could provide a reference for other similar projects.