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Due to the advantages of Laplace domain in both time and frequency domains, the dynamic analysis and control tools in engineering software like MATLAB and Python have been designed based on it. Dynamic analysis of structures requires determination of the overall transfer matrix, which is obtained by multiplying the structure's transfer matrix (TM) with the load TM. With the input vector of unit intensity white-noise processes and the overall TM, the structural responses can be obtained. Furthermore, having the load TM is crucial for implementation of active control systems. In this article, the TM of along-wind loads was estimated for a tall building using the proper orthogonal decomposition (POD) method and the genetic algorithm (GA). To evaluate the effectiveness of the proposed approach, an example of a tall building was provided. The wind load cross-power spectral matrix (XPSD) was decomposed using POD technique, followed by the truncation of higher loading modes. Subsequently, the loading TM was derived by estimating the target non-linear functions with linear transfer functions through GA technique. Then, the responses of the structure were computed using the loading TM. The results demonstrated the efficacy of the proposed method in acquiring the loading TM and predicting wind-induced responses. [ABSTRACT FROM AUTHOR]

International Energy Agency (IEA) predicts India's AC stock will reach 1144 million units by 2050, making it the second largest ACs holder globally. Studies on the effect of building geometry on cooling load reduction are primarily focused on material and envelope specifications. However, studies on building morphological parameters in the Indian context are scarce. Therefore, this research quantifies the effect of four morphology predictors, namely, FL (floor number), ESA (exposed surface area), CZB (conditioned zones per building), and CZF (conditioned zones per floor) on cooling load in 75 dominant residential built forms of Navi Mumbai. The selected buildings are simulated using the Rhinoceros 6 tool with the energy plus plugin. Despite having the same simulation inputs, envelope parameters, and conditioned volume, the results indicated a 90% variation between the compact and loosely designed forms. Multiple Linear Regression shows that the four predictors explain 78% (R² = 0.78) of variation in the cooling load. It is observed that tall buildings show greater efficiency in cooling load reduction due to lesser CZF values. Also, an increase in CZB and a decrease in ESA significantly reduce the mean cooling load due to compactness and wall sharing, respectively. [ABSTRACT FROM AUTHOR]

Tuned mass dampers (TMDs) are a useful control of vibrations for tall buildings and can be considered equal to burdens such as breezes and earthquakes. The better limits for TMD are to reduce the earthquake vibrations of tall buildings including soil–structure interaction (SSI) influences. This study proposes the multi-objective Black Widow Optimization (BWO) with Elman neural network (ENN) computation that is brought on to find the optimal limits of TMD. Considering that this proposed model analyzed the mass, stiffness, and damping ratio of TMD to get the maximum accelerations and displacement of 40 story building model, from the execution results, starting from this proposed BWO–Elman model to the expected methodology, the most outrageous TMD limits are better, likewise, the reduction of acceleration and displacement are 25% and 19.86% in the proposed study. This study assists the researchers with a better understanding of earthquake vibration and leads the fashioners to achieve superior TMD for tall designs. The impact of vibration control on the displacements and accelerations of both controlled and uncontrolled buildings is investigated in this work. It uses a MATLAB software technique to analyze their modal replies, moreover, this proposed optimal TMD model is compared with conventional techniques by acceleration and stiffness parameters. [ABSTRACT FROM AUTHOR]

Space efficiency in Singaporean tall buildings results from a complex interplay of historical, architectural, engineering, technological, socioeconomic, and environmental factors. The city-state's innovative and adaptive approach has enabled it to overcome the challenges associated with skyscraper construction, leading to the development of some of the most advanced and sustainable high-rise structures in the world. However, there is currently a lack of detailed analysis on space utilization in Singaporean high-rise buildings. This study addresses this gap by examining 63 cases. The main findings of this research: 1. Residential functions, central core layouts, and prismatic shapes are the most frequent. 2. Concrete material with a shear-walled frame system is the preferred structural choice. 3. Average spatial efficiency is 80%, and the core-to-GFA (Gross Floor Area) ratio averages 17%. These metrics vary from a minimum of 68% and 5% to a maximum of 91% and 32%, respectively. These insights offer valuable guidance for Singaporean construction professionals, particularly architects, helping them make informed design decisions for high-rise projects. [ABSTRACT FROM AUTHOR]

A settlement analysis of a new high-rise building, the Nivy Tower, in Bratislava, Slovakia, is presented in this paper. A 3D finite element model was prepared. A non-linear elasto-plastic material model with double hardening and increased stiffness in a small-to-very-small strain range was adopted for the Tertiary (Neogene) subsoils. Due to the lack of an appropriate in-situ test, the results from a 1D compression test were used for the calibration of the soil input parameters. However, the results from these tests, especially in the primary loading, are often biased due to the effects of soil disturbance during the preparation of the sample. Therefore, a different procedure has been proposed, in which the stiffness parameters were obtained from unloading-reloading branches of 1D compression tests. It could be concluded that the predicted and measured settlements are in a reasonable match for all the points measured. The computed distributions of the vertical displacements and those measured by sliding micrometres show greater differences from a depth of twenty meters beneath the foundation slab. [ABSTRACT FROM AUTHOR]

This study focuses on the vibration control effect of the spring vibration isolation system (SVIS) on a super high-rise building located on the subway (BLS) and the transmission mechanism of vibration in super high-rise BLS. Firstly, the 1:35 scale shaking table test model of super high-rise BLS is designed, the rationality of the shaking table test model is verified, and the shaking table test is implemented. Secondly, the finite element model (FEM) is established and verified based on the results of the shaking table test. Finally, based on verified FEM, the vibration control effect of SVIS on super high-rise BLS and the vibration transmission mechanism of super high-rise BLS is analyzed. The results show that the vibration response of the BLS show amplification trend along the height direction. The amplification of vibration response of BLS is effectively controlled by SVIS. The higher the floor, the greater the reduction coefficient, and the better the control effect. The reduction coefficient above 10F is mainly distributed above 0.80 due to the SVIS. The BLS equipped with the SVIS maintains the degree of Z -direction vibration and 1/3 octave vibration acceleration level that is within the limits stipulated by the specifications. The first-order vertical frequency of BLS equipped with the SVIS is adjusted from 65 Hz to 8 Hz, far from the favorable frequency range of the subway wave. [ABSTRACT FROM AUTHOR]

The existing theories for along-wind loads on slender structures, based on the "strip assumption" overlook the three-dimensionality of turbulence. However, numerous experimental phenomena contradicting the "strip assumption" highlight the need to consider the effects of three-dimensional turbulence (3D effect). This study develops an analysis model that considers the three-dimensionality of turbulence and derives a function containing the section-shape-dependent characteristic parameters to represent the 3D effect. A method for identifying the parameters through a wind tunnel test is proposed to solve this function. The parameters for the square cross section are then identified in two different turbulence fields, revealing that the identification parameters of both cases are nearly identical. This similarity indicates that the parameters are independent of the turbulence validating the proposed theories. Finally, the 3D effect on square cross-sectional structures with different aspect ratios under various turbulence integral scales is analyzed. The results showed that as the ratio of the turbulence integral scale to the windward width of the structures increases, the 3D effect reduces, but the rate of reduction slows down. In addition, increasing the aspect ratios of structures further mitigates the 3D effect, enhancing the accuracy of the "strip assumption." These results can be a reference for evaluating the accuracy of the "strip assumption" theory for square cross-sectional high-rise buildings in atmospheric boundary layer turbulence. The proposed method can be applied to investigate the 3D effect on along-wind loads of slender structures with various cross-sectional shapes. [ABSTRACT FROM AUTHOR]

The manuscript introduces a new structural system called the reinforced concrete (RC) space grid cassette multi-tube structure for high-rise buildings. A case study building is analyzed using this system and compared to a conventional RC frame-core tube structure. Through modal analysis in the software "Midas Gen", the torsional effect and control indices like inter-story displacement ratio, maximum displacement, etc. are compared between the two structural systems. The results show that the space grid cassette system has smaller displacement ratios, displacements, inter-story torsion angles, and thus better torsional resistance compared to the conventional frame-core tube system. Based on these analyses, the manuscript concludes that the RC space grid cassette multi-tube structural system has superior seismic performance and is more suitable for irregularly shaped high-rise residential buildings. [ABSTRACT FROM AUTHOR]

The rapid progress of development in the Surabaya area, especially in areas crossed by the Waru segmentation fault, Wiyung District, and Lakarsantri, is marked by the number of residential developments and tall buildings which will certainly contribute to the value of natural disaster vulnerability, earthquakes. So, to reduce the risk value of loss to casualties and material losses from potential earthquakes, further mitigation is needed. The aim of this study is to determine the dominant factors for building vulnerability and earthquake natural disaster mitigation in the Waru segmentation fault area. One of the analytical methods used is the Importance Index (IMPI) method, this analysis method is carried out to determine the most dominant risk level from existing risks and bowtie analysis is used to manage, reduce and mitigate the most dominant risks. Based on the results of research and risk assessment, the most dominant risk level variable for building vulnerability due to Waru segmentation faults is variable 2 c (finishing with heavy loads such as concrete or precast panels that are not firmly attached to the structure) with an IMPI value of 83.13 %. The presence of finishing with heavy loads such as concrete or precast panels that are not firmly attached to the structure in the event of an earthquake disaster in the Waru Fault will endanger and can bring down people around the building. To reduce the risk of casualties due to earthquakes in the Waru Fault, it is necessary to prevent by providing an additional number of dynabol bolts, enlarging the reinforcement at the façade and canopy joints, locking concrete cavities with special concrete stucco additives and conducting surveillance monitoring during construction. [ABSTRACT FROM AUTHOR]

This research proposes an innovative method to convert the modeling of three-dimensional structures to the modeling of two-dimensional structures for the stability analysis of long tubular buildings. The process of the proposed method is in the form of modeling the equivalent frame and then modeling the reduced frame using the equivalent moment of inertia for beams and columns. The second-order elastic analysis has been performed considering the effects of P-Δ and P-δ. Framed-tube and frame tube-in-tube systems have been used for modeling. Newton's Raphson and Crisfield's Arc Length methods have also been used for nonlinear analysis. The accuracy and speed of analysis of the new method have been checked by comparing the displacements and drifts in the modeled systems for 40 and 50 stories tall buildings. For each structure, two framed-tube and tube-in-tube systems are considered. In the presented method, the number of nodes and elements in the reduced model is much less. The method presented in this research can reduce the amount of calculating the response of tall structures and the duration of the analysis. One of the advantages of the presented method is the acceptable accuracy of the analysis along with the high speed of the analysis. The results show that the proposed method has reduced the amount of calculations by 80% along with a 5% reduction in the accuracy of structural responses. [ABSTRACT FROM AUTHOR]

This study employs a combination of theoretical analysis, Similarity simulation, and computational fluid dynamics (CFD) to examine the airflow caused by the stack effect under different leakage conditions in high-rise buildings and the transport of fire smoke. Building on previous research, we quantify the leakage area using a formula and classify it into two categories, "tight" and "leaky." Based on the analysis results, we conduct a similarity simulation experiment in a small-scale high-rise building experimental platform with a height of 5.2 m to create a certain size of leakage area at the bottom and record carbon monoxide concentration at different locations and times. The obtained result is then compared with the numerical simulation result, and the similarity simulation results match well with the numerical simulation results. The findings demonstrate that increasing the leakage area accelerates the transport of smoke due to the stack effect, particularly at higher floors. This paper also discusses strategies to impede smoke diffusion, providing valuable references for the safety design of high-rise buildings. [ABSTRACT FROM AUTHOR]

Urban vitality is a core feature of sustainable cities and neighborhoods. Acknowledging the significant role of the spatial and physical attributes of built urban landscapes in influencing urban vitality, scholars and planners in the field of urban studies have meticulously examined the relationship between urban morphology and variations in urban vitality. While most previous studies have primarily focused on a narrow range of factors when analyzing urban form, often neglecting its multifaceted nature, this study utilizes urban morphometrics using Python's Momepy library to offer a comprehensive typology. It integrates diverse urban components from individual buildings and streets to entire neighborhoods into a unified, holistic framework, providing a more integrated understanding of urban form's influence on urban vitality. Our spatial econometric models identified higher building floor areas, taller and narrower streetside buildings, diversely aged buildings, and higher building coverings on lots as favorable urban form settings for urban vitality. Measuring urban morphology with advanced methods and identifying their relationship to urban vitality provides insightful implications for urban planners and designers for creating vibrant cities and neighborhoods. Practical Applications: This study utilizes advanced methods to assess the design and layout of cities and neighborhoods and analyzes their effects on urban vitality. The Momepy Python package is used in this study to capture urban form in terms of size, density, layout, diversity, and connectedness. This study measures how diverse urban morphologies affect the variation of urban vitality captured by mobile phone data. This study introduces an integrated approach that identifies spatial relationships between buildings and street networks into a comprehensive framework. This holistic approach can suggest effective strategies for decision-making by urban planners and policymakers to create livable and sustainable cities and neighborhoods. Moreover, this study reveals how the effects of the urban morphology on urban vitality vary depending on the time of day and day of the week. The core findings suggest that urban planners and designers should consider spatial configurations of buildings and streets as well as residents' behavior over time. [ABSTRACT FROM AUTHOR]

The interflat cross-contamination of air pollutants such as coronavirus disease 2019 (COVID-19) in built environments has become a growing concern. This study investigates the effect of the geometrical details of building facades on wind-induced airborne pollutant transmission routes in high-rise buildings. Parametric studies of different external-shading elements of buildings, wind speeds, and wind directionality are considered. A high-resolution computational fluid dynamics (CFD) using a realizable k-epsilon turbulence closure model is employed to analyze the airflow field. For the windward single-sided ventilation case, the reentry ratio from the source room to the other unit under prevailing, 45°, and 90° wind directions are quantified, and the possible interflat cross-contamination routes are simulated. The transmission route is highly dependent on a building's architectural features, wind speed, wind directionality, and location of the source room. The result shows that external shading plays a crucial role in mitigating or accelerating airborne pollutant transmissions. A building with horizontal shadings restricts vertical cross-contamination between flats, but it allows horizontal interflat cross-contamination. However, buildings with vertical shadings reduce the risk of horizontal cross-contamination but increase the probability of vertical cross-contamination. The egg-crate shading minimizes the risk of both horizontal and vertical cross-contamination. A smooth facade building is highly susceptible to cross-contamination for a wide range of wind directionality. Therefore, this study is helpful for architecture and building science for the analysis of airborne pollutants, for tracing the routes of cross-contamination in residential buildings, and for reducing the risk of transmission of respiratory diseases such as COVID-19. [ABSTRACT FROM AUTHOR]

Designing a fully modular building, which is without the support of any separate lateral resisting elements, has the advantage of rapid site assembly, but runs the risk of a brittle style of connection failures in a rare earthquake event. Thus, this form of construction is currently limited to low-rise buildings. Isolating the building from its base and allowing the rocking motion to occur has been proven to be effective in dissipating energy and prolonging the natural periods by the lifting of the structure, thereby alleviating high strength demand on the building itself. To avert overturning, the amount of the rotation of the building needs to be controlled, and the use of superelastic tendons as a restraint is a promising solution. Previous studies into the seismic performance with this novel form of construction have been limited to experimenting with a rigid block or a single lumped mass system. In this study, this approach of seismic isolation is extended to a high-rise modular building with distributed mass and stiffness. A scaled-down model of a 19-story fully modular building, which was partially restrained by superelastic tendons, was tested on a shaking table. The key objective was to study the deflection profile and distribution of internal forces up the height of the superelastic tendon–restrained building and examine the contributions by the higher modes. The internal forces predicted by the analytical model developed in the study are shown to be in good agreement with experimental measurements. Practical Applications: Modular construction shortens construction time and reduces environmental impacts. Currently, fully modular buildings, which have a high degree of prefabrication, are limited to low-rise constructions because of concerns over the overturning risk in major earthquake events. A new seismic safe design employing a superelastic tendon is introduced in this article to extend fully modular construction to high-rise buildings. The building is designed to rotate about its base when subjected to high intensity ground shaking. The amount of rotation is controlled by the superelastic tendon in order to avoid overturning from occurring. Meanwhile, internal forces taken up by the structural elements within the building were kept much lower than a conventional fixed base building. The dynamic testing of the miniature model of a 19-story building on the shaking table was featured in the study, which laid down principles that are essential for the formulation of effective guidelines for the structural design of this type of building. [ABSTRACT FROM AUTHOR]

High-rise structures with large aspect ratios are subjected to unexpected motions under wind excitation. Structural vibrations induced by vortices in the wake were captured by aeroelastic real-time hybrid simulation (aeroRTHS) in the companion paper. An effective and practical method is critical for explaining the mitigation of adverse wind loading impact upon these structures. Analyzing the performance of structural control devices against wind excitation in an aeroelastic wind tunnel test often is time- and cost-intensive. In this paper, aeroRTHS testing is extended to include (1) a vibration control device numerically added to the numerical substructures and tested to mitigate the cross-wind oscillation in the aeroRTHS framework; and (2) the use of 128 pressure sensors installed on two side faces of a physical building model in a boundary layer wind tunnel (BLWT) at the University of Florida Natural Hazards Engineering Research Infrastructure Equipment Facility (UF NHERI EF) to provide a more complete description of the wind-force distributions imparted on nine building configurations both with and without a tuned mass damper (TMD) at various constant wind speeds. Wind-force distribution was characterized in the time domain in terms of time histories of equivalent forces and displacements, and envelopes of wind forces. Frequency response analysis was conducted based on power spectral densities of input equivalent wind forces and output structural dynamic response. Results from the aeroRTHS tests demonstrated that the aeroRTHS method is capable of investigating aeroelastic structures with passive mitigation devices. The aeroRTHS tests in the wind tunnel demonstrated that the augmentation of buildings with TMDs is an effective way to attenuate the cross-wind vibration in tall buildings. [ABSTRACT FROM AUTHOR]

Research on design rules and methods for architectural heritage is an important aspect of conservation practice. Nevertheless, efforts to recover and divulge design methods for Modern Heritage remain limited. This paper is related to the recent structural assessment of a 15-storey heritage building built in 1950, during which a document describing the original seismic analysis of this structure was identified. The methodology employed is of particular interest, as it involves the application of pioneer concepts of dynamic analysis in the design of the first tall buildings in Mexico. The primary aim of this paper is to review the seismic design criteria for the case under study in order to contribute to the state of the art in Modern Heritage. The review includes a comparison between the dynamic characteristics estimated during the design and the results of recent ambient vibration tests and numerical modeling. Several sources of error among the design criteria were identified. Notably, the fundamental period estimated during the design was 38% larger than the experimental value due to an underestimation in stiffness, which introduces significant uncertainty into the design. Overall, the review shows the evolution of seismic analysis over time and provide valuable insights for the study of similar buildings. [ABSTRACT FROM AUTHOR]

Based on the Guangzhou Business Center project, a typical super high-rise building with an asymmetric plan, taking the construction speed, closure time of mega braces and belt trusses as influencing factors, a parametric analysis on its lateral and vertical deformations, as well as the maximum stress of key structural members was conducted. The analysis results indicated that the construction speed had a relatively small impact on the deformation and the maximum stress of key members. However, synchronous closure of belt truss compared with the delayed closure would result in smaller horizontal and vertical deformation differences, as well as the stress of belt truss. Meanwhile, the closure timing of the mega braces had little influence on the vertical deformation difference and the stress of belt truss. And the earlier the closure, the smaller the horizontal drift ratio, the greater the maximum stress of the mega braces. Further, deformation control measurements were brought forward. On the one hand, FEM simulation was carried out according to the above construction suggestions. On the other hand, real-time monitoring was also used. Finally, by comparing both results, proposed construction deformation control measures and simulation methods were verified. [ABSTRACT FROM AUTHOR]

Previous research has indicated that buckling-restrained braces (BRBs) increase the lateral story stiffness, resulting in a shortening of the natural period, which leads to an increase in the seismic input into the buildings, especially in high-rise buildings. Additionally, research has also revealed that the long-period seismic motions with a long duration possibly induce a difficulty to ensure the toughness of the BRB members, owing to the large cumulative strains caused by the repeated axial forces. To overcome these issues, this paper proposed a displacement-restraint buckling-restrained brace (DR-BRB) in which no axial force appears initially, and the axial force occurs with a delay under the designated vibration amplitude. Therefore, the natural period can maintain the same level as the moment frame. This study performed five cyclic loading tests to reveal the delayed-action mechanism of BRBs, using gusset plates with multiple slot holes. The test results confirmed that the designated starting point of the brace action is accurate, and the hysteretic behavior of the brace is good. Furthermore, the design equations of the joints were formulated and verified through the test results. Finally, the joint behavior and validity of the proposed design equations were verified by finite element analyses for the single bolt model and the overall joint model. [ABSTRACT FROM AUTHOR]

Summary: The regular operation of the subway negatively impacts the occupants of super high‐rise multi‐tower buildings located on over‐depot (MBLO), causing undesirable vibrations. To save engineers time and computational cost, an improved one‐dimensional impedance model of super high‐rise MBLO is established to predict undesirable vibration in the design phase and devise measures to enhance human comfort. The stiffness factor of the thick plate of a large chassis is introduced, and the impedance relationships of coupled beam and floor based on the equivalence of mass and bending stiffness are considered for an improved one‐dimensional impedance model. The vibration response of multi‐story buildings and super high‐rise MBLO is predicted by an improved one‐dimensional impedance model and compared with field measurements and experimental results, respectively. The results show that the vibration transmission law of super high‐rise MBLO can be more accurately predicted when the stiffness factor of thick plates and the impedance relationships of coupled beam and floor are adopted in an improved one‐dimensional impedance model of super high‐rise MBLO. [ABSTRACT FROM AUTHOR]

Summary: Cracks can develop in high‐rise buildings because of long‐term environmental changes and extreme loading events such as strong winds or earthquakes. Although deep learning‐based identification methods can efficiently identify cracks, the accuracy of crack identification in high‐rise buildings needs to be improved due to the lack of crack datasets specifically related to high‐rise structures. Moreover, the number of available images of cracks in high‐rise is limited. To this end, this paper establishes an intelligent crack identification method based on a photorealistic synthetic modeling technique. First, a computer graphics (CG) model of a high‐rise building with assumed damage is constructed. Subsequently, the CG model is utilized to generate a dataset that includes photorealistic images of the high‐rise building as well as corresponding labels for various components and types of damage. The generated dataset is then used to train a DeepLabv3 + neural network for structural component and damage identification, followed by validation by employing images of both synthetic and full‐scale high‐rise buildings. The trained network can accurately identify different components in images of the full‐scale, high‐rise building and identify cracks that are intentionally synthesized in those images. The results show that the synthetic dataset generated by the CG model not only allows for fast and efficient labeling for the purpose of neural network training but also outperforms methods that do not consider any application‐specific context in crack identification. [ABSTRACT FROM AUTHOR]

In order to reasonably determine the advanced closing time of the post-subsidence pouring belt, the research on the closing time of the post-subsidence pouring belt was carried out considering the effect of pile bottom sediment. Based on the results of model test and in-situ pile test results of Qinwang Square complex project, a single pile settlement model considering the effect of pile bottom sediment was proposed. Based on the settlement model of single pile, the earliest sealing time of the post-subsidence pouring belt was calculated according to the common combination of working conditions during construction, and the change of the stiffness of single pile under floating load was considered. The results show these as follows. When the sediment thickness meets the design requirements, the differential settlement caused by the combined conditions of dead load, live load and floating load is the largest, but when the sediment thickness is large, the combined conditions of dead load and live load will change to the control condition. When the sediment thickness is small, the differential settlement develops linearly under all working conditions. In this case, the late deformation can be predicted by the observed sedimentation value in the early stage. When the sediment thickness is large, the closing time of the post-subsidence pouring belt is significantly delayed, or even cannot be closed in advance. [ABSTRACT FROM AUTHOR]

Urbanization has led to a significant increase in the construction of tall buildings in Canada. The design of tall buildings must ensure structural integrity in withstanding lateral loads, such as wind and earthquakes. The tendency for a specific lateral load to govern building design varies based on the building characteristics, building height, and location of the building. There is a need to identify the governing lateral load (i.e., wind or earthquake) for use in the preliminary design and city-scale assessment. This study examines the governing lateral loads for tall buildings across different Canadian regions through a parametric analysis of a typical high-rise building based on the Commonwealth Advisory Aeronautical Council (CAARC) building. This research evaluates varying building heights, structural systems, and geographic locations under the guidelines of the National Building Code of Canada (NBCC). The analysis identifies the dominant lateral load, providing insights into assessing the existing infrastructure and optimal design strategies for enhancing building sustainability and resilience. Our findings highlight the critical role of geographic location in determining lateral load impacts and the necessity of context-specific design to promote long-term structural performance and environmental sustainability. [ABSTRACT FROM AUTHOR]

Summary: Acceleration measurements are often used for model updating of civil engineering structures, especially in the case of seismic monitoring. It is yet unclear if accelerations alone would generate an accurate and robust finite‐element (FE) model. This study examines this notion and analyzes the possibility of using other vibration monitoring data for model updating of shear‐wall tall buildings. This study compares the accuracy and robustness of the FE models being optimized via accelerations, roof displacement, wall rotations, interstory drift ratios, and the linear combination of these measurements. A numerical case study is analyzed using Timoshenko beams for modeling the lateral vibration of a benchmark 42‐story building under seismic excitations. Results show that the acceleration response of the examined building is mostly governed by its higher vibration modes. Depending on the characteristics of ground motions, using accelerations alone may generate an FE model biased towards higher‐order modes without effectively capturing the lower‐order modes. For instance, the first modal frequency of the updated FE model could be 12.0% lower than the true value, and the reconstructed displacement and rotation responses are noticeably inaccurate. Employing multi‐source monitoring data for model updating, for example, the combinations of roof displacement and acceleration measurements, could reduce the normalized root‐mean‐square errors in displacements by more than 70%. This study also quantifies the robustness of the FE model under various measurement noise levels and 50 pairs of earthquake records. Finally, the effects of multi‐source data on FE model updating are validated via experiments on a 7‐story shear wall building. Analysis reveals that a more accurate and robust FE model can be determined via a combination of accelerations and top displacement than via acceleration alone. [ABSTRACT FROM AUTHOR]

Wind resistance performance research on the influence of the exterior features of high-rise buildings is an essential part of structure design. In this paper, the wind resistance tests of three high-rise building models with different concavity shapes on the horizontal plane were investigated using the wind tunnel experiment. The CAARC (Commonwealth Advisory Aeronautical Research Council) standard high-rise model was adopted as the background model (BG model for short), and the other two comparison groups with different planar configurations were designed, one with concave corners around the building (T1 model) and the other with concavity in the middle of the long side of the building (T2 model). The distribution laws of the average wind pressure coefficients of the building facades and roofs under the whole wind azimuths were analyzed comprehensively. The results show that the external shape plays a certain role in wind pressure distribution. Among the three high-rise building models, the most unfavorable positive wind pressure coefficient on the facades occurs in the T2 model (a 4.7% increment compared with the BG model), while the most unfavorable negative wind pressure coefficient appears in the T1 model (a 25% increment compared with BG model). Furthermore, it is noted that the architectural appearance of the T1 model makes the flow field around the building more streamlined, reflecting more favorable wind-resistance performance, including a maximum reduction of 47.2% in the least stresses per unit area on the roof. The research in this paper can provide some references for the design of different exterior features of high-rise buildings. [ABSTRACT FROM AUTHOR]

In recent years, coupled shear walls have been used more often because they provide a significant percentage of the total stiffness of a tall building total horizontal bracing system. This article presents an analytical procedure for the static and dynamic analysis of coupled shear walls of a bay using a continuous model type – CTB of three fields. The coupled shear wall is modeled as a continuous structure consisting of the parallel coupling of a Timoshenko extensible beam and a shear beam. Using a variational approach, the equilibrium equations, constitutive laws, and boundary conditions are derived by applying Hamilton's principle to the relevant Lagrangian function. Closed-form solutions are provided for the static deflection of the coupled shear wall under general profile lateral loads and the periods of vibration of the coupled shear wall under vertical loads uniformly distributed along its height. A validation of the static analysis was carried out, and to find the range of validity of the continuous model and proposed solution methods, a parametric analysis was carried out. The results are encouraging and show that the proposed analytical solutions have excellent correspondence with respect to the finite element method; they are accurate, reliable and involve low computational cost at a preliminary stage, and can be used as a verification method at the final stage of structural analysis and design. [ABSTRACT FROM AUTHOR]

In the present study, the principal objective is to investigate the role of multiple tuned mass damper (MTMD) to reduce aerodynamic effect of wind force on "V" plan-shaped high-rise buildings with the various internal limb angle. Distinct cases have been made by considering the angle between the limbs is 90° which is gradually increased from 90° to 150° with 15° regular interval and decreased from 90° to 40° with 10° regular interval maintaining same plan area and limb width subjected from 0° to 180° wind incidence angle with 30° regular interval. Computational fluid dynamics (CFD) is adopted to determine the aerodynamic coefficients by numerical simulation. A polynomial expression has been proposed to compute force, moment, and torsional coefficient along X, Y, and Z direction from the entire result for avoiding rigorous calculation. Dynamic wind time history in along and crosswind is obtained using maximum force coefficient. The dynamic response analysis such as peak displacement, acceleration is obtained for selected models with MTMD and effectiveness of MTMD is computed. Finally, the influence of MTMD and internal angle variation on the wind-induced response of "V" plan-shaped buildings have been observed to determine suitability of internal angle variation based on the numerical result. [ABSTRACT FROM AUTHOR]

An experiment was carried out using a scale model of a tall building, with the goal of investigating the role of individual buildings in the dispersion of air pollution. Pollutant dispersion around an isolated building with a height-to-length aspect ratio of 1.4 is investigated using simultaneous particle image velocimetry and planar laser induced fluorescence. Dye is released from a ground-level point source five building heights upstream of the tall building. It was found that in this case the scalar plume was dispersed laterally strongly by the building, but only slightly vertically. It is hypothesized that this is due to 94% of the plume impinging below the stagnation point on the front of the building and being drawn into the horseshoe vortex. We expect this fraction would be lower in a case in which the building is in an array of smaller buildings, and that this would lead to more vertical dispersion. [ABSTRACT FROM AUTHOR]

To reduce the risk of unexpected cost of rework (COR), a variety of predictive models have been developed in the construction management literature. However, they primarily focus on prediction accuracy, and rather less attention has been paid to the trustworthiness of prediction models. This increases operational risk and hinders its integration in related decision-making. Aiming to reduce the utilization risk and increase the reliability of COR prediction models, this study exploits the graph convolutional network (GCN) model, which enhances representativeness by accommodating interrelationships among the root causes of nonconformances. The GCN can process a more representative input network that provides COR records while factoring in the shared root causes of nonconformance in the resulting COR. The proposed approach achieved a COR prediction accuracy as high as 85%, which is significantly higher than that of any existing cost prediction model. The demonstrated accuracy and lower risk of the proposed GCN model thus enhance the reliability of the prediction and trust in its outcome, facilitating its integration into developing rework prevention strategies and relevant resource allocation for construction professionals. The study contributes to construction project management by proposing a novel COR prediction model that embodies accuracy, representativeness, and interpretability. Whereas we tailored the GCN model to predict COR with a focus on nonconformance root causes, it is noted that rework costs can also be influenced by other project factors, such as site safety. Practical Applications: Managing rework costs is a critical challenge in the construction sector, necessitating predictive models that are not only accurate but also trustworthy. This study leverages graph convolutional network (GCN) to offer a prediction model that is both accurate and reliably interpretable. The GCN model enriches cost of rework (COR) predictions by analyzing how different project elements, such as design flaws or material issues, are interconnected, providing a more holistic view of potential rework triggers. The customization of the GCN model is crucial, requiring specific adjustments based on individual project requirements and decision-making goals, and remains relevant across diverse construction projects. The proposed predictive tool processes complex data and provides insight into how various project factors interplay to affect rework costs. By providing a clear rationale behind its predictions, it supports more informed decision-making in allocating resources and developing strategies to prevent rework, ultimately leading to more efficient and cost-effective project management. Having COR prediction based on a comprehensive understanding of all related project factors equips professionals with insight about the predicted COR impact on the overall construction budget and its related root causes. This, in turn, fosters greater confidence among project stakeholders and sets a stronger basis for strategic planning, resource allocation, and risk management. [ABSTRACT FROM AUTHOR]

The São Paulo Metro is expanding its network in the São Paulo Metropolitan Area inhabited by 21 million people. Metro Line 6 connects the north of the city to the existing metro network further South. The construction of Line 6 currently represents the largest infrastructure project in Latin America, combining the excavation of tunnel boring machine (TBM) and conventional tunnels, cut‐and‐cover stations and a number of deep emergency exit shafts. This paper presents the main features of the TBM tunnel excavated in the South stretch through the Tertiary soils of the São Paulo Basin and through the challenging Embu Complex, which consists of a mixture of fractured rock, saprolite and residual soils. The alignment runs under the dense urban grid of São Paulo under high‐rise buildings and other infrastructure, such as existing Metro lines. [ABSTRACT FROM AUTHOR]

High-rise buildings are sensitive to multihazard loads from both short and long-term perspectives. Adding tuned mass dampers (TMDs) is a well-established method to improve the performance of tall buildings, but the cost-benefit of adding TMDs is still a research question to be tackled. To answer this question, a methodology for optimal simultaneous design of reinforced concrete components and TMDs in high-rise buildings is developed for the first time. A cost-benefit focused optimization problem is defined, adopting a monetary cost function that includes direct and indirect costs and the multihazard long-term repair costs. Design variables related to the primary structure and the dampers are selected, as well as a set of constraints. The shear wall rigidities and capacities are included by generating a database of moment-curvature relations, followed by a curve-fitting procedure. An efficient gradient-based algorithm is developed to solve these challenging problems. Using this algorithm, 35 problems are solved, considering three building heights and three metropolitan areas in Israel, with their specific hazard and cost inputs. The results show that for 40-story buildings, adding TMDs is not profitable. For 50-story buildings, this is profitable for Jerusalem, marginally profitable for Tel-Aviv and not practical for Haifa. For 60-story buildings, adding TMDs is profitable for all the locations, with the greatest benefit being detected for Jerusalem, and then for Tel-Aviv in second place. The results are explained by the different building heights, wind load magnitudes and surface selling prices. The framework is shown to be flexible and appropriate for a preliminary TMD profitability assessment. [ABSTRACT FROM AUTHOR]

FOUR FRANKFURT – New high‐rise buildings in Frankfurt am Main On the former Deutsche Bank site in Frankfurt's city centre, an impressive new ensemble of four high‐rise buildings and a shared six‐storey base building with underground car park is being built.The shell of the building is now largely complete and the topping‐out ceremony was held in September 2023. The high‐rise buildings are 233 metres (T1), 178 metres (T2), 125 metres (T3) and 105 metres (T4) high. Office use is planned for the T1 and T4 towers, and residential use and a hotel are planned for T2 and T3. The office space on the top floors of T1 will be the highest in Germany. The inner‐city location poses particular challenges for the project. For example, the excavation pit was constructed using the down method. The different requirements for the use of the towers led to different construction methods for the typical storeys: while the shell of the residential towers was made of in‐situ concrete, prefabricated elements proved to be the optimized construction method for the office towers. The report is divided into three parts. The first part presents the project and provides overviews of the components. The second part deals with the bracing system of the towers, including measures to increase stiffness. Finally, the third part describes special construction methods. [ABSTRACT FROM AUTHOR]

Piled rafts and pile groups are the common types of deep foundations for tall buildings subjected to combined loading. Their complex behavior made their design and analysis very complex and sometimes uneconomical. This paper explores the distribution of lateral load on piles within a piled raft and pile group under a constant vertical load. The study utilized experiments with small-scale models of piles and rafts to observe the behavior. The response of each pile was recorded and analyzed with respect to lateral displacement. The results indicated that in the case of piled rafts under lateral load, the rear piles are resisting more load than the front piles, unlike in pile groups where front piles carry more load than rear piles. This behavior continued until the number of piles reaches nine, thereafter the load-carrying behavior shifted, and front piles began to carry more lateral load. The reason behind this shift is that as the number of piles increases, the raft contact pressure decreases and subsequently decreases the stiffness of soil below raft and hence the piled raft starts behaving as a pile group, where front piles carry more lateral load. [ABSTRACT FROM AUTHOR]

In high-rise buildings with large indoor and outdoor temperature difference, neglecting the effect of stack effect in smoke exhaust shafts may cause calculation error of the fluid network model. In this paper, the mathematical model of kitchen smoke exhaust system considering the influence of stack effect was put forward and it can be inserted different range hood sub-models. Compared with the results of six working conditions of the model without considering the stack effect, the error of the proposed model were reduced by 7.6%, 4.3%, 4.1%, 2.8%, 2.4%, and 2.1%. While the indoor and outdoor temperature difference varies from - 5 °C to 49 °C, the effect of stack effect on the pressure in the flue and the flow rate for each user was studied for six operating rates s. The results show that under the combined effect of stack effect and flue resistance, the static pressure of the kitchen smoke exhaust system showed a low-high-low distribution, and the maximum static pressure in the flue moved toward the bottom with the increase of temperature difference. User flow rates exhibit a low-high-low-high distribution, with an increased flow rate in the bottom users and the largest flow rate in the top users. [ABSTRACT FROM AUTHOR]

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In the construction of super high-rise buildings, building machines (BMs) are increasingly replacing traditional climbing frames. Building machine jacking operation (BMJO) is a high-difficulty and high-risk stage in the construction of the top mold system. To guarantee the operational safety of the BMJO and to enhance its intelligent control level, a digital twin (DT)-based monitoring method for the operation status of the BMJO is proposed. Firstly, a DT framework for monitoring the operation status of the BMJO is presented, taking into account the operational characteristics of the BM and the requirements of real-time monitoring. The functions of each part are then elaborated in detail. Secondly, the virtual twin model is created using Blender's geometric node group function; artificial neural network technology is used to enable online prediction of the structural performance of the BMJO and a motion model is established to realize a real-time state mapping of the BMJO. Finally, taking a BM project as an example, the DT system is established in conjunction with the project to verify the feasibility of the DT framework for monitoring the state of the BMJO. It is proved that the prediction results have high accuracy and fast analysis speed, thus providing a new way of thinking for monitoring and controlling the safe operation of the BMJO. [ABSTRACT FROM AUTHOR]

It has been challenging to predict the peak spatial accelerations of tall buildings experiencing wind-induced motion. Frequency domain solution techniques using modal analysis are typically employed for wind tunnel studies, in which it is necessary to combine the modal responses statistically to estimate the peak spatial responses. An improved solution technique is presented that treats the determination of the peak accelerations as an optimization problem with a closed-form solution. The peak X, Y, and torsional accelerations are solved using matrix multiplication of the modal response covariance matrix and mode shapes. The peak resultant acceleration is determined by solving an eigenvalue problem. The proposed solution method accommodates correlation between modal responses, which existing methodologies have neglected. A case study is presented in which significant correlation exists between a building's modal responses due to a strong across-wind loading exciting two modes simultaneously. A tuned mass damper (TMD) is incorporated into the building design to reduce wind-induced motions. The TMD transfers energy between structural modes of vibration and increases the correlation between modes considerably. Neglecting modal correlation effects results in a considerable overestimation of some spatial responses and a considerable underestimation of other spatial responses. While a bidirectional TMD decreased the modal responses by a similar amount, due to the strengthened modal correlation not all directions of motion were decreased as much as would be expected if the correlation was not present. It is therefore necessary that DVA systems designed for tall buildings properly account for modal correlation. [ABSTRACT FROM AUTHOR]

The immediate vicinity of buildings of different floors causes damages of the smoke and ventilation channels work of the low-rise buildings. This is dangerous for the resident's health and lives. To determine the impact of high-rise buildings on the operation of air channels of a nearby two-story building, experimental research has been carried out in a wind tunnel. Charts and analytical formulas have been designed for determining the buildings aerodynamic coefficients depending on wind directions and the channels height. An increase of the channel height results in an increase in static rarefaction in smoke and ventilation channels. Increasing rarefaction increases the efficiency of the natural ventilation system and ensures the residents health and life. [ABSTRACT FROM AUTHOR]