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With the development of modern long-span cable-stayed bridges, due to the Parallel strand cable (PSC) being assembled on-site strand by strand, which has the advantages such as no need for large-scale equipment for cable-making, delivery, hoisting, traction, tensioning, and the corrosion protection of the cable is excellent, it is more and more favored by designers.As the load-bearing components, the stay cables are known as the life cable of the cable- stayed bridge. Its reliability and durability are the key factors that determine the safety and the service life of the cable-stayed bridge. In accordance with the requirements specified in international recommendations, in-depth research has been carried out on cable fatigue, anti- corrosion, vibration control to optimize OVM250 PSC system. All research results have been successfully applied to cable stayed bridge projects.

Objective(s): In this study, a stable bear bile-loaded pH sensitive in-situ eye drop gel was prepared for sustain delivery and enhanced therapeutic application. Materials and Methods: Bear bile-loaded in-situ ocular gels with different Carbopol/Hydroxypropyl methylcellulose (HPMC) ratios were prepared and their stability was tested in PBS at a series of pH at 40 °C. The morphology was observed by SEM examination and rheology was observed by Rheometer equipped with a 60-mm cone-plate at apex angle of 1°. Gel erosion and release kinetics of Tauroursodeoxycholic acid (TUDCA) was determined by HPLC. While, the in vivo dwelling time was obtained after administering the fluorescent-loaded gel in ocular disease-free New Zealand rabbits. Finally, biocompatibility and toxicity was observed by irritation test and H&E staining of eye-ball tissues, respectively. Results: The bear bile-loaded in-situ ocular gel showed excellent stability at different pH (pH 5.0, 5.5, 6.0, 6.5, 7.0 and 8.0) up to 5 days, and bear bile extract significantly attenuated the gelling ability of the in-situ gel. The viscosity of in-situ gels formulation was decreased with increase in shear rate (0.01 to 100 s-1), and morphological examination of freeze-dried preparation showed three-dimensional reticular structure at physiological pH. The in-situ ocular gel exhibited promising sustained drug release up to 160 min in vitro, and showed prolonged retention time up to 3-folds in vivo. Finally, the biocompability data confirmed that the formulation did not induce any toxic effects and was completely compatible with eye tissues.Conclusion: pH sensitive in-situ ocular gel provides new research opportunities to efficiently treat eye diseases.

Cable tension identification based on mode shapes extracted from vibration measurements is a relatively new method. In this method, the cable is equivalent to a beam model hinged at its ends and under axial tension with an unknown length to eliminate the effects of boundary conditions. This study focuses on the influences of sensor arrangement in the measurements on the accuracy of the tension identification. For this purpose, full-scale cable experiments have been carried out, where a number of sensors were attached to the cable to record cable acceleration during artificial excitation. The eigenvalue realization algorithm (ERA) has then been applied to identify the mode shapes and frequencies of the cables from the multiple acceleration measurements. The effects of different sensor arrangement schemes and cable tension identification method based on higher- order modes are compared and discussed.

The Stockbridge damper (SD) has been used for vibration mitigation of suspender cables subjected to vortex-induced and other types of resonant vibrations. This paper studies its effectiven...

Suspension type cable system is an important type of cable bearing system, its dynamic problems have always been the key to the structural design, health monitoring, and vibration control. In view of this, an exact dynamic analysis method for suspension type cables is proposed by the author. The dynamic characteristic of the suspension cable system is studied by a full-scale cable test. By comparing with experimental results and finite element solutions, the accuracy and universality of the proposed method are verified. The results show that the calculation result agrees well with the measured results, and the maximum relative error of each condition is basically no more than 2%. Through parameter identification, the bending stiffness, cable force, and the installation position of the weights are identified and corrected, and the calculation errors after parameter identification are controlled within 1%, which significantly improves the calculation accuracy and further verifies the accuracy of the proposed method.