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• The proposed tropical cyclone model is completely driven by a set of environmental variables. • This model reproduces the spatial and temporal characteristics of observed tropical cyclones. • The model achieves remarkable balance between computational complexity and efficiency. • This model will provide decision-makers with valuable information regarding potential wind-induced hazards. • When future climate data are fed into this model, the impact of climate change on tropical cyclones can be evaluated. This paper presents an environment-driven tropical cyclone (TC) model for the Western North Pacific basin, which comprises a revised Poisson regression genesis model, a tailored beta-advection track model, and a fast intensity model. The TC model reproduces the temporal and spatial distributions of genesis events, the motion pattern of tracks, as well as the intensity evolutions along tracks. Risk analyses for Hong Kong and along the southeast coastline of mainland China demonstrate that this model can simulate extreme TC events with high fidelity. And the Gaussian mixture model outperforms the Frank Copula in approximating the joint distributions of the annual maximum wind speeds and the corresponding wind directions. This model is driven by a set of environmental variables including relative vorticity, relative humidity, sea surface temperature, vertical wind shear, potential intensity, sub mixed layer depth stratification, mixture layer depth and so on. This enables the model to not only reproduce historical records, but also make predictions for future TC behaviors under climate change with combination of global climate models. Besides, the computational efficiency of the TC model is comparable to traditional purely statistical models. The proposed model can also be coupled with other natural hazard models to conduct multi-hazard analysis. [ABSTRACT FROM AUTHOR]

This paper presents the durability design of concrete structures in the Hong Kong–Zhuhai–Macau (HZM) sea link project for a design service life of 120 years. Among all the durability issues, this paper focuses on the model-based durability design of concrete structures in the project subject to the action of marine chlorides. The mechanism and modeling of chloride penetration into concrete are reviewed in depth and the applicability of models for durability design is evaluated. On the basis of long-term exposure tests and in-place structural investigations during the past 30 years in South-eastern China, the design model for concrete structures in the HZM project is established. The statistical properties of model parameters are analyzed in details and compared to other chloride ingress models. Using the established HZM model for chloride ingress and specified durability limit state (DLS), the design parameters are first evaluated through a fully probabilistic analysis in terms of service lives (50 years, 120 years) and target reliability levels ( β = 1.3, 1.5, 1.8). The partial factor format for durability design is then established and the partial factors are calibrated from the first order reliability method (FORM) from specified service life and specified reliability level. The design results from the partial factor design equation are given for different exposure zones, and the achieved reliability index is verified for each design through the full probabilistic method. Finally remarks are given on the HZM model and its application in durability design of RC elements. [ABSTRACT FROM AUTHOR]