The Guangzhou New TV Tower (GNTVT), currently being constructed in Guangzhou, China, is a supertall structure with a height of 610 m. This tube-in-tube structure comprises a reinforced concrete inner tube and a steel outer tube adopting concrete-filled-tube columns. A sophisticated structural health monitoring (SHM) system consisting of over 600 sensors has been designed and is being implemented by The Hong Kong Polytechnic University to GNTVT for both in-construction and in-service real-time monitoring. This paper outlines the technology innovation in developing and implementing this SHM system, which includes (i) modular design of the SHM system, (ii) integration of the in-construction monitoring system and the in-service monitoring system, (iii) wireless-based data acquisition and Internetbased remote data transmission, (iv) design and implementation of a fiber Bragg grating sensing system, (v) structural health and condition assessment using static and dynamic monitoring data, (vi) verification of the effectiveness of vibration control devices by the SHM system, and (vii) development of an SHM benchmark problem by taking GNTVT as a test bed and using real-world measurement data. Preliminary monitoring data including those obtained during the Wenchuan earthquake and recent typhoons are also presented.

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Blue infrastructure is an important component of urban green infrastructure, due to its capacity for water cycle regulation and soil formation, as well as supporting unique biodiversity. Urban ponds, as part of urban blue, can harbour a diverse assemblage of aquatic macroinvertebrates. As yet, it is not clear how urbanisation affects macroinvertebrate diversity. In this study, we focus on diving beetles (Dytiscidae) in the Helsinki Metropolitan Area, Finland, to investigate how urbanisation affects their diversity, as well as the effects of margin steepness and the presence or absence of fish on urban dytiscids. We sampled dytiscids using 1-L activity traps in 14 fishless ponds and 11 ponds with fish, at ten sites. We applied generalised linear mixed models (GLMM) and non-metric multidimensional scaling (NMDS) to analyse the effects on dytiscid assemblages. We found that urbanisation had a negative effect on species richness but not on abundance. Steepness of pond margins and the presence or absence of predatory fish, affected both species richness and abundance: dytiscids prefer ponds with gently sloping margins; they have 80% higher species richness and are 79% more abundant in fishless ponds, and medium to large-sized dytiscid species are more capable of coexisting with fish. Urban wetlands can support a diversity of dytiscids at the regional level, and the presence of ponds without predatory fish is beneficial for maintaining dytiscid diversity. We recommend maintaining a diverse range of ponds and wetland habitats for the maintenance of aquatic biodiversity in urban regions.

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