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Current structural design codes usually treat multiple hazards separately, and probabilistic backbones are rare for extreme hazard combinations, e.g., earthquake and strong wind, which may cause unforeseen damage to engineering structures exposed to multiple extreme hazards during their lifecycles. This study presents an innovative copula-based approach to construct the joint cumulative distribution function (JCDF) of the peak ground acceleration (PGA) and strong wind speed ($V$). Six commonly used Archimedean copulas are applied to bond the JCDF with the corresponding marginal cumulative distribution functions (MCDFs) of PGA and $V$. A total of 76 low-probability-high-consequence extreme events with a simultaneously occurring earthquake and strong wind are abstracted from data recorded from 1971–2017 in Dali Prefecture, China. The statistical analysis results show that the Frechet and truncated Weibull distributions are the optimal expressions for the marginal distributions of PGA and $V$, respectively, while the Joe Archimedean copula can yield good JCDF estimation. Monte Carlo simulation is employed to establish a target dependent multihazard database that can be used for the performance-based design of engineering structures against multiple natural hazards. A high-rise building is used to study the performance under the multihazard of an earthquake and strong wind. The results show that the maximum inter-story drift ratio of the building under multiple hazards increases by 14.4–21.3% compared with the structural response induced by an earthquake alone.

For high-rise buildings subjected to ambient excitations such as typhoons and earthquake actions, their structural responses may include non-stationary features. Under such conditions, traditional modal identification methods may not be applicable due to the violation of the stationary assumption of the response signals. To deal with this issue, a novel modal identification method is presented in this paper based on combination of the variational mode decomposition (VMD) and direct interpolation (DI) techniques. Through numerical simulation study of a three-story frame structure, the effectiveness and accuracy of the combined VMD-DI method for modal identification of the structure are validated for the case of the structural responses containing non-stationary properties and high-level noise. Moreover, the novel method is further applied to the field measurements of acceleration responses of a 600m high skyscraper during a typhoon. The identified results verify the applicability and accuracy of the combined VMD-DI method in field measurements. This paper aims to provide an effective tool for modal identification from non-stationary structural responses of high-rise buildings.

The vortex shedding phenomenon caused by flow separation at windward corners of a high-rise building would lead to significant vortex-induced vibrations (VIVs). This paper proposes a novel and efficient two-way coupled fluid-structure interaction (FSI) method named as equivalent lumped mass system (ELMS) method to study the wind-induced responses of the Common Advisory Aeronautical Council (CAARC) building. The numerical results of ELMS are validated based on available data of aeroelastic tests. To verify the computational efficiency of ELMS method, this study also employs the other two two-way coupled FSI methods (free-form deformation (FFD) method and mapping interpolation algorithms in system coupling (MIASC) method) to simulate the response of the same high-rise building. Furthermore, the VIV mechanisms of the high-rise building are explicitly discussed based on the numerical results of the ELMS method combined with large eddy simulation (LES). The outcomes show that the ELMS method could well capture the significant amplification of cross-wind response and “lock-in” phenomenon at the range of the critical wind speed. Moreover, the computational efficiency of the ELMS method is much improved compared with the other two FSI methods. The spatial correlation and spectral coherence of the local loads at different heights of the building are increased significantly at the “lock-in” stage. The findings in this study would facility the comprehensive understanding of the VIV phenomena of the high-rise building and provide an efficient two-way coupled FSI method for engineers and researchers involved in the wind-resistant design of slender tall buildings.

Interference influence of the spacing and height ratio on the modal generalized force and wind-induced response of the low-rise building roof due to one adjacent high-rise building is investigated at three typical wind directions of 0^∘, 90^∘ and 180^∘, where the low-rise building was, respectively, located at the upstream, side-by-side and downstream of the high-rise building. The mean and standard deviation of the modal generalized force of the first vibration mode mainly exhibits reduction effects and amplification effects, respectively, at the wind direction of 0^∘ and 90^∘ at small building spacing, and first experiences shielding effects and then becomes amplification effects when the height ratio increases at the wind direction of 180^∘. The maximum displacement mainly presents reduction effects at the wind direction of 0^∘, the interference factor decreases with the increase of the reduced frequency in engineering range, and the minimum interference factor is close to 0.2. At the wind direction of 90^∘, the maximum displacement mainly presents amplification effects, these effects are obvious when the spacing ratio is small and the height ratio is large, and the maximum interference factor is close to 2.2 when the reduced frequency is larger than 0.3. At the wind direction of 180^∘, the maximum displacement shows significant amplification effects when the building spacing is small and the height ratio is large, the amplification effects gradually weaken and change into shielding effects as the building spacing increases or the height ratio decreases, and the minimum interference factor is close to 0.3. The minimum displacement experiences amplification effects at all three typical wind directions.

For high-rise buildings subjected to typhoon or earthquake actions, the excitations are likely non-stationary, which inevitably violates the stationary assumption that is generally adopted by conventional modal identification methods. Under such a condition, conventional modal identification methods may not be applicable, and their performances need to be evaluated. To this end, the performances of seven widely used modal identification algorithms for structural modal estimation under non-stationary excitations are evaluated via a numerical simulation study. Then, three methods with good performance are selected to evaluate their applicability and accuracy for field measurements involving non-stationary excitations. From the comparative study, a time–frequency domain method with the best performance among these seven methods is employed to investigate the structural dynamic properties of a 509-m-tall skyscraper under typhoon and earthquake excitations. Based on the reliable modal estimates, the relationships between the modal properties with response amplitude and environmental temperature are presented and discussed. This paper aims to identify the effective methods for accurate estimation of structural modal parameters based on non-stationary structural responses and investigate the structural dynamic properties of high-rise buildings under typhoon and earthquake excitations.

The base-isolation technology has been increasingly applied in high-rise buildings in recent years. Previous studies have shown that the unfavorable wind-induced response can be effectively reduced by a certain degree of hysteretic energy dissipation after the yielding of the isolation system under strong wind load. However, a large relative inelastic displacement at the isolation level will occur under this condition, which is likely to exceed the width of seismic gap, and cause a structural impact with the adjacent structures (i.e. retaining wall or other barriers). Such wind-induced impacts may have detrimental consequences on the structural performance and have not been investigated much before. This study prospectively investigated the wind-induced impact behavior of base-isolated high-rise buildings with adjacent structures. The multi-story superstructure is modeled as a linear elastic shear building, while the isolation system is represented by bilinear hysteresis restoring force model. An impact element combined with linear spring and damper is used. The story wind load is determined by its cross power spectral density (PSD). Responses for two kinds of typical impact including crosswind and along-wind impact are examined by time history analysis. The results demonstrate that the impact will increase the fluctuation components of superstructure displacement, shear force and bending moment to some extent compared with that of the base-isolated building without impact. The floor accelerations, especially floors close to the base, are significantly increased during impact. The impact has no effect on the mean component of each response. At last, a parametric analysis is carried out to explore the influences of various impact parameters on the inelastic impact response. The results of this study can help to better understand the impact behavior of base-isolated high-rise buildings under strong wind excitation and be useful for performance-based wind resistance design.

Seismic response spectra are amongst one of the most important tools for characterizing earthquake ground motions. In design practice, the response spectra are presented without including any load history, hence the nonlinear analysis of structures based solely on conventional earthquake response spectra is theoretically unsound, particularly for long-period or vertically irregular high-rise buildings. In this paper, a concept of seismic damage evolution is introduced and the method of analysis for characterizing the process of seismic damage to structures under earthquakes is presented. Seismic damage evolution spectra for analysis and design of high-rise buildings are then developed as an effective means of describing and simplifying earthquake ground motions. These spectra are shown to be very useful in selecting the ground motion-time history and, particularly, validating the equivalent static-load analysis and design of high-rise buildings under near-fault pulse-like ground motions. Case studies of the seismic inelastic performance of two vertically irregular, tall buildings are presented considering the seismic damage evolution spectra.

The seismic behavior of the structures equipped with ATMD is often investigated based on the rigid base assumption without considering soil-structure interaction (SSI) effects. The SSI effects significantly modify the dynamic characteristics of the structures, while these changes may be ignored in the design process of the controllers. The present paper aims to address the issue of the SSI effects on the seismic behavior of the structures and performance of the adopted controllers. For this purpose, a mathematical model is developed for the time domain analysis of tall building equipped with ATMD including SSI effects. Considering the fixed base case and three types of ground states, namely soft, medium and dense soil, the numerical studies are carried out on a 40-story structure subjected to different earthquake excitations. Two well-known controllers, proportional-integral-derivative (PID) and linear-quadratic regulator (LQR) controllers, are employed for tuning control force of ATMD in different conditions of ground state. A particle swarm optimization (PSO) algorithm is used for the optimum design of Tuned mass damper (TMD) parameter and the gain matrices of the controllers in both cases without and with SSI effects. It is found that TMDs are more effective for the higher soil stiffness and their efficiencies are degraded in soft soils. Furthermore, the SSI significantly affects on the optimum design of the PID and LQR controllers. The adopted controllers are significantly able to mitigate the peak top floor displacement of the tall building. In addition that the PID controller is a simple strategy with design variables much less than LQR controller, it performs better than the LQR controller in most earthquakes for different conditions of ground state. The performance of the controllers decreases with increasing soil softness, so that ignoring the SSI effects may result in incorrect and unrealistic results of the seismic behavior of the structures.

With the characteristics of high-speed transportation, the elevator has an overwhelmingly crucial meaning footnote in an auxiliary evacuation high-rise building with more than 30 floors causing the time to be the deciding factor under the emergency condition. The study shows that using the stairway or elevator separately cannot achieve the best effect. The elevator’s evacuation time depends on the number of occupants on each floor and the elevator’s carrying capacity. This paper discusses how to use the stair and elevator to optimize the hybrid evacuation in high-rise buildings and proposes two goals for the evacuation model of high-rise buildings under emergency conditions. One is that both the last occupant to use the stairway and the last occupant to use the elevator reach the safe place simultaneously. The other is that we fine-tune the evacuation destinations of the occupants to balance the utilization of each evacuation path as much as possible. We present the optimization method with three steps, and the evacuation time shrunk by up to 57% according to the baseline. Finally, we compare the optimized hybrid evacuation and the single evacuation method to the previous work and give the results of the experiments.

Building Integrated Photovoltaic (BIPV) is a resort to save energy and reduce heat gain of buildings, utilize new and renewable energy, solve environment problems and alleviate electricity shortage in large cities. The area needed to generate power makes facade integrated photovoltaic panel a superb choice, especially in high-rise buildings. Numerous scholars have hitherto explored Building Facade Integrated Photovoltaic, however, focusing mainly on thermal performance, which fails to ensure seismic safety of high-rise buildings integrated photovoltaic. Based on connecting forms of the glass curtain wall, a connector jointing photovoltaic panel and facade was designed, which underwent loading position and size optimization. Static loading scenarios were conducted to test and verify the connector's mechanical properties under gravity and wind loading by means of HyperWorks. Compared to the unoptimized design, the optimized one saved material and managed to reduce maximum deflection by 74.64%.

The current situation of groundwater post-processing produced by High-rise building foundation pit construction in Xuchang city was studied by field investigation, which certified that the present situation and problems of groundwater waste was very serious, the post-processing system of groundwater was put forward based on existing problems correspondingly. This paper put forward suggestions and measures for protection of limited groundwater resources, accelerate the sustainable development of Xuchang city, improve the Xuchang natural ecological environment, accelerate the construction of ecological civilization and social civilization has important guiding significance.