High-rise Structures Research Articles

Tornado-induced instability assessment of super large hyperbolic reinforced concrete cooling towers

Cooling towers are typical high-rise thin-walled structures which are of hyperbolic rotating shell structure type and significantly sensitive to wind loads. Wind-related local instability is the key control factor in the design of structural geometric shape and tower shell thickness optimization. In fact, this kind of stability analysis has only conducted aiming at normal climate (such as monsoon, etc.) under the guideline of series of national Codes. In order to deal with the issues under disaster climate, physical and numerical investigation to evaluate local stability performance of a super large cooling tower (SLCT) under tornado environments based on Buckling Stress State (BSS) method is implemented. Besides, whole process elastic–plastic collapse simulation of the SLCT exposed to the tornados was also carried out to study the failure mechanism and re-evaluated the reasonability of the well-accepted BSS method for structural wind-resistant design. The results revealed that the tornados would have obvious adverse effects on the structural local stability when the SLCT is located at the tornado vortex core radius compared with those under traditional synoptic winds. The swirl ratios and the central distances between the SLCT and the tornado vortex core have significant effects on the local instability of the SLCT. The extended elastic–plastic collapse simulation discovered that the position of the first crack during SLCT collapse process is basically consistent with the critical position from the elastic local stability analysis of the SLCT, indicating that strengthening measures can be carried out in advance at the critical position for structural local stability improvement under tornado conditions. Besides, the extended elastic–plastic collapse numerical simulation of the SLCT could be as the effective supplement to the structural elastic stability assessment (such as BSS method) in the wind-resistant design of the SLCT.

Improved lumped parameter model for shear wall–frame structures with geometric and material nonlinearities

Lumped parameter macroscopic structural models, such as those consisting of springs and rigid sticks, are useful for parametric studies and probabilistic analyses of individual building structures as well as for regional-level assessments on building stock. The existing lumped parameter models (LPMs) for shear wall–frame dual systems exhibit some drawbacks. There is a discrepancy in their arrangement of springs. They are calibrated to match only two modal periods of the original multi-story or even high-rise building structure. The existing models also have limitations when confronted with the P-Δ effect. After a careful investigation, this paper developed new schemes of spring-stick assemblies that accurately reproduce the elastic stiffness matrix of a two-dimensional Euler–Bernoulli or Timoshenko beam–column element and cope with geometric and material nonlinearities. The developed assemblies, which are essentially lumped parameter substitutes for beam–column elements, can be used to build LPMs for moment frames and shear walls. For moment frames, the traditional fishbone model is converted into a LPM that not only reflects the beam-to-column stiffness ratio and strength ratio but also captures the P-Δ effect. Combining the LPM for shear wall with the lumped parameter fishbone model results in an improved LPM for wall–frame dual systems. Together with lumped floor masses, the improved LPM is able to accurately predict all the global vibration modes and nonlinear seismic responses of a dual system. The proposed LPM possesses distinct advantages when simplified macroscopic models are preferred for building structures.

Analysis of Space Efficiency in High-Rise Timber Residential Towers

High-rise timber residential towers (≥eight-stories) represent a burgeoning and auspicious sector, predominantly due to their capability to provide significant ecological and financial advantages throughout their lifecycle. Like numerous other building types, spatial optimization in high-rise timber residential structures stands as a pivotal design factor essential for project viability. Presently, there exists no comprehensive investigation on space efficiency in such towers. This study analyzed data from 51 case studies to enhance understanding of the design considerations influencing space efficiency in high-rise timber residential towers. Key findings included (1) the average space efficiency within the examined cases was recorded at 83%, exhibiting variances ranging from 70% to 93% across different cases, (2) the average percentage of core area to gross floor area (GFA) was calculated at 10%, demonstrating fluctuations within the range of 4% to 21% across diverse scenarios, and (3) no notable distinction was observed in the effect of various core planning strategies on spatial efficiency when properly designed, and similar conclusions were drawn regarding building forms and structural materials. This research will aid in formulating design guidelines tailored for various stakeholders such as architectural designers involved in high-rise residential timber building developments.

Enhancing Tower Crane Safety: A UAV-Based Intelligent Inspection Approach

Tower cranes play a crucial role in the construction industry, facilitating the vertical and horizontal movement of materials and aiding in building construction, especially for high-rise structures. However, tower crane accidents can lead to severe consequences, highlighting the importance of effective safety management and inspection. This paper presents a novel approach to tower crane safety inspections using Unmanned Aerial Vehicles (UAVs) equipped with high-definition cameras and an intelligent inspection APP system. The system utilizes real-time kinematic (RTK) positioning and digital image processing to perform efficient and comprehensive inspections, reducing the reliance on manual labor and associated risks. A case study demonstrated the method’s practicality and effectiveness, with the UAV inspections capable of identifying 76.3% of major hazards, 64.8% of significant hazards, and 76.2% of general hazards within a 30-minute timeframe. Preliminary identification rates were also promising. Despite the initial requirement for manual drone piloting and the current manual review of images, the approach shows significant potential for enhancing safety in the construction industry. Future work will focus on integrating AI for hazard recognition and automating the inspection process further. The proposed method marks a step forward in tower crane safety management, offering a more efficient and accurate alternative to traditional inspection methods.

Innovative Brace Damper System for Mitigating Seismic Response in High-Rise Steel Structures

This study investigates the seismic response of a G+14 steel frame building with composite columns using fluid viscous dampers. The effectiveness of these dampers is assessed through analysis employing the Equivalent Static Method, Response Spectrum Method, and Time History Analysis in ETABS. Results indicate a significant 40–60% reduction in displacement and storey drift, underscoring the efficacy of fluid viscous dampers in enhancing structural resilience. This research underscores the importance of innovative damping systems in mitigating seismic risks in tall steel buildings.

Comparison of mass timber structure and RC structure with regard to sustainability by life cycle assessment

Since the 18th-century Industrial Revolution, high-rise have played a crucial role in addressing urbanization challenges, remaining a primary solution for urban living. However, this architectural advancement has also contributed to environmental decline. Presently, steel and concrete stand out as the predominant materials for high-rise construction, with well-documented significant carbon emissions. This paper delves into the potential of timber as an environmentally friendly alternative in high-rise construction to address such environmental concerns. Furthermore, it examines the impact of these structures on land load. The paper conducts a comprehensive review of life cycle assessment (LCA) studies and offers a comparative analysis of the climate change impacts associated with timber versus conventional materials like reinforced concrete (RC), underscoring the urgent need for sustainable development in the vertical expansion of our cities. The findings demonstrate that both the mass and carbon emissions of high-rise timber structures, in comparison to RC structures, can be reduced by approximately half. The paper aims to underscore the benefits of timber in comparison to conventional reinforced concrete methods, thereby informing material selection in favor of sustainable urban development.

Topology optimization of the flat steel shear wall based on the volume constraint and strain energy assumptions under the seismic loading conditions

In structural engineering systems, shear walls are two-dimensional vertical elements designed to endure lateral forces acting in-plane, most frequently seismic and wind loads. Shear walls come in a variety of materials and are typically found in high-rise structures. Because steel shear walls are lighter, more ductile, and stronger than other concrete shear walls, they are advised for usage in steel constructions. It is important to remember that the steel shear wall has an infill plate, which can be produced in a variety of forms. The critical zones in flat steel shear walls are the joints and corners where the infill plate and frame meet. The flat infill plate can be modified to improve the strength and weight performance of the steel shear walls. One of these procedures is Topology Optimization (TO) and this method can reduce the weight and also, increase the strength against the cyclic loading sequences. In the current research paper, the TO of the infill steel plate was considered based on the two methods of volume constraint and maximization of strain energy. Four different volumes (i.e., 60%, 70%, 80%, and 90%) were assumed for the mentioned element in the steel shear wall. The obtained results revealed that the topology configuration of CCSSW with 90% volume constraint presented the highest seismic loading performance. The cumulated energy for this type of SSW was around 700 kJ while it was around 600 kJ for other topology optimization configurations.

Performance evaluation and FRP strengthening of concrete-filled steel tubular columns subjected to vehicle impact

Concrete-filled steel tubular (CFST) columns have been widely used in multi-story and high-rise frame structures. During the service period, they may suffer vehicle impact due to traffic accidents or terrorist attacks. This paper numerically evaluates the performance of CFST columns under vehicle impact and investigates the effects of carbon FRP (CFRP) wrapping arrangements on performance improvement of the columns. Before that, a numerical model was developed to simulate the responses of CFST columns without and with FRP wrapping under vehicle impact and post-impact axial compression, and then calibrated by reported tests. Evaluation results show that the performance of CSFT columns under vehicle impact is divided into five levels, i.e., no repair required, rapid repair required, minor repair needed, major repair needed, and replacement needed. The performance level decreases with the increase in the vehicle weight or speed and increases with the increase in the column diameter or steel tube thickness. The column height has little effects on the performance level. A higher axial load ratio, e.g., 0.5, might reduce the performance level. Besides, a CFST column tends to fail in flexure mode when hit by F800 medium truck, while it may fail in flexure & shear mode when hit by C2500 pickup truck. Investigation results indicate that FRP wrapping with each layer orientation of 90° (i.e., in the longitudinal direction) and 0° (i.e., in the hoop direction) present the best performance improvement for a CFST column possibly undergoing flexure & shear and flexure failure, respectively. The increase of the number of FRP layers effectively improves the performance levels of CFST columns but the excessive demand may be not economical. It is not necessary to employ an FRP wrapping range of 100% for improving the vehicular impact performance level of a CFST column to the expected one.

A Comprehensive Study on Net Zero Energy Buildings and Sustainable Construction Materials with Low Carbon Contents

One-third of the world's greenhouse gas emissions come from the building industry, with embodied carbon from the manufacture of building materials accounting for a sizable portion of these emissions. Prior research has mostly focused on examining the carbon emissions of low-rise structures, but it has failed to consider the significant influence that high-rise buildings have on a city's overall carbon emissions. Net-zero energy buildings (NZEBs) combine intelligent energy management strategies with conventional design knowledge to facilitate a sustainable and eco-friendly transition. The NZEB building revolution has the potential to become a long-term structural pillar for structures to come. The purpose of this study is to assess how various design factors and the embodied carbon in high-rise structures relate to one another. Additionally, the goal of this research is to keep annual consumer energy comfort in a home NZEB at its highest level without using any electricity from the electrical grid. In order to achieve long-term climate goals, our work emphasises the socio-economic advantages of adopting NZE buildings and further empowers consumer participation to minimise energy waste and carbon emissions. The findings provide a foundation for constructing high-rise structures in a more ecologically conscious manner to lower the structure's carbon emissions. The evaluation and comparison of the embedded carbon values takes into account the carbon emissions from the transportation and material manufacturing processes.

Shaking Table Tests and Numerical Simulation Study on the Eccentricity of the Center of Mass of Full-Frame-Supported High-Rise Building Structure with Thick Plate Transfer

Shaking Table Tests and Numerical Simulation Study on the Eccentricity of the Center of Mass of Full-Frame-Supported High-Rise Building Structure with Thick Plate Transfer

The Wind Profile Characteristics of Super Typhoon Lekima Based on Field Measurement

Many cities in coastal areas are prone to typhoon disasters due to their location on the Pacific storm path, and the direct effect of catastrophic winds can lead to the destruction of low-rise buildings and severe damage to high-rise structures. The purpose of this study was to enhance the understanding of boundary layer wind profiles of strong typhoons in coastal areas and reduce property losses and casualties caused by wind disasters. Based on the field measurements of wind profile acoustic radar in coastal areas, the variation characteristics of the boundary layer wind profile during the passage of super typhoon Lekima were first studied in depth, and the evolution law of the typhoon boundary layer profile was summarized. Then, the effects of typhoon horizontal structure, topography, wind speed, and time distance on the characteristics of the typhoon profile were discussed, respectively. Finally, the evolution characteristics of wind profile parameters were obtained by fitting three wind profile theoretical models. Due to the strong variability of typhoon profile morphology, the theoretical model of wind profile is only applicable to the wind profile from the bottom to the low-level jet height of typhoons, while wind parameters are closely related to the spatial location of the typhoon wind field.

Modelling and analysis of strength and durability properties of internal curing concrete using PEG 400 and artificial neural network

The traditional curing processes necessitate a large amount of water. This is especially difficult in locations where there is a lack of water and for construction of high-rise structures. In this research article, we provide a remedy by inventing concrete that will not require additional water for curing. In the present work, polyethylene glycol was utilized as an internal curing agent in varying percentages. The internally cured concrete with polyethylene glycol was cured at ambient conditions, whereas the conventional concrete without polyethylene glycol was kept in water for curing. Fresh and hardened characteristics of concrete with and without polyethylene glycol are compared. The results revealed that 1.5% polyethylene glycol is an optimum percentage where maximum strength and durable properties are achieved. The microstructure of internal curing concrete indicates that the pore sizes are small compared to conventional concrete. The crystallite size is smaller in internal curing compared to conventional concrete mixtures, resulting in an acceleration of the hydration process in concrete with smaller crystallites.Further experimental results are compared with ANN. Predicted results are very close to experimental values.

Analysis of the influence of external factors on the deformation of high-rise buildings in the process of their construction and operation

During the construction and operation of high-rise buildings, their vertical axis changes its position in space. The greater the height of the structure, the greater the amplitude of oscillations. This causes problems of geodetic construction support and the need to monitor deformations during the operation of high-rise structures. In real conditions, part of the structures will be in the shade and their temperature will be lower than the structures that will be under the influence of solar radiation, the temperature of which will be much higher. Thus, the building will deform as a result of uneven thermal expansion, that is, it will bend. From DBN B.1.3-2:2010 "Geodesic works in construction". Also, during the geodetic provision of the construction and operation of high-rise buildings, changes in the temperature regime of building structures should be taken into account in connection with significant absolute values of changes in the geometric dimensions of the building as a result of thermal expansion, which significantly exceed the accuracy regulated by the regulatory document. The article examines and analyzes the influence of external forces on changes in the geometry of high-rise structures and focuses attention on solving the scientific problem of geodetic support for the construction and operation of modern high-rise structures under dynamic loads.

A comprehensive review on scour and scour protections for complex bottom-fixed offshore and marine renewable energy foundations

Due to the marine environment's complexity, optimising offshore foundations' design is still a major focus of the scientific and industrial community, since foundations represent a large portion of the total investment. Scour is one of the main causes that lead to ultimate, and service limit states, impacting design optimization and costs. Scour at monopile foundations has been extensively studied. However, advances in scour protections for hybrid structures, and other bottom-fixed foundations for offshore renewable energy harvesting technologies are often kept confidential by stakeholders, and knowledge gaps must be covered. Thus, the present paper provides a summary of the most recent physical and numerical studies related to scour and riprap scour protections for complex bottom-fixed foundations, such as jackets, tripods, gravity-based foundations (GBF), high-rise structure foundations (HRSF), and suction buckets, while covering other marine energy harvesting technologies as well, including wave energy converters (WEC) and tidal energy converters (TEC). This manuscript presents knowledge gaps, recent improvements, and potential studies on hybrid foundations – offshore wind turbine foundations combined with WECs or TECs. It is shown that offshore scour protection is a study field with a wide margin of development, but crucial for the future of the offshore renewable energy sector, thus pointing out key challenges and major opportunities for future research.

Modal-based fragility analysis of high-rise tubular structures: A methodology for vulnerability assessment

This study addresses the limitations of current vulnerability assessment processes for tall buildings, which fail to incorporate the effects of higher modes and the resulting structural vulnerability to seismic hazards. Additionally, the extensive computational resources required for assessing tubular high-rise buildings make vulnerability assessments almost impossible. This study proposes a new methodology for assessing the modal-based structural vulnerability of high-rise reinforced concrete (RC) tubular buildings by incorporating nonlinear response and reducing computational effort. The proposed methodology discreetly develops the vulnerability information of each structural vibrational mode separately using nonlinear time history analysis rather than the linear Modal Response Spectrum Analysis (MRSA). The methodology includes steps for establishing vulnerability information for high-rise tubular buildings, and a case study of a 55-story RC building with core wall is presented to demonstrate the methodology. The vibrational modes of the building were decoupled and analyzed separately using single degree of freedom (SDOF) systems, and fragility curves were developed for three different limit states using various intensity measures. The obtained fragility relationships were compared with the curves of another structure of similar class. The results indicated good compatibility and significance of incorporating higher vibrational modes in assessment of structural vulnerability, thus, proposed methodology can be extended to any structural configuration of tubular buildings.

Building Structural Design Innovation and Code Development

In recent years, Some new structural systems and design difficulties of high-rise and super high-rise buildings were emerged in Shenzhen, such as forced displacement and non-forced displacement, story lateral stiffness calculation method, frame-core wall structures with partial perimeter frame beams missing, super high-rise structure with great height-width ratio, high-rise less shear walls in one direction structure, conjoined tower structures, high-rise structure with inclined column, mega structure with belt truss, rare earthquake design method etc. The emergence and solution of these problems reflect the innovation of the structural design of high-rise buildings. Meanwhile, Structural design has encountered many difficulties and new problems. The solutions to these problems sometimes conflict with the current Chinese code, or there are no relevant provisions in the Chinese code. The current Chinese code is the basis for designing of high-rise buildings, which is the crystallization of the wisdom of previous generations, but the emergence of various new types of building structures has brought about numerous difficulties in structural design. Therefore, during the design process, it is necessary to conduct research, innovation, supplementation, and development of the current code. In view of this situation, this paper combines the previous engineering practical experience and introduces some structural design points of complex super high-rise buildings located in Shenzhen. It is for designers' reference, which also provides content for the revision of the specification.

Research on Design and Analysis of Multi-Story Building by using AutoCAD and STAAD-Pro

“The population of India is the second highest in the world as per the 2022 report” [1]. In order to live well, there is an increasing demand for adequate infrastructure. People are migrating from rural to urban regions. Problems will rise due to the high population in urban areas. Due to a lack of available land for construction in metropolitan areas, high-rise building structures are becoming more necessary to address the population density issue. High-rise structures are in high demand, and their construction must be completed without compromising any of the three criteria of cost, timeliness, and safety. AutoCAD design software enables the production of both 2D and 3D drawings for use in constructing multi-story buildings. This study aims to utilize the software package STAAD-Pro to analyze and design a multi-story building, following the production of 2D and 3D drawings using AutoCAD. STAAD-Pro offers a far quicker method of structural analysis and planning for the likelihood of the fewest faults. The design involves load calculations and analyzing the whole structure by STAAD Pro. “The method used in STAAD Pro analysis is Limit State Design followed by Indian Standard Codes. The loads considered for designing the building are dead loads, live loads, and Wind loads. For analyzing a multi-storied building, one has to consider all the possible loadings and see that the structure is safe against all possible loading conditions” [2]. The aim of this study is to analyze the structural behavior of the building and ensure that it meets the necessary design standards and codes. To remain competitive in the constantly expanding market, it is crucial for structural engineers to optimize their time management. This study highlights the importance of using advanced software tools in the design and analysis of complex structures to ensure their safety and stability.

Исследования математических моделей процессов деформаций зданий и сооружений

Purpose. The article is aimed at analyzing changes in the dynamic characteristics of a building and establishing the dependence of shear deformation accelerations on the building's storey to predict the effect of seismic vibrations on the technical condition of the building, taking into account the engineering and geological properties of the foundation. Methodology. A number of instrumental observations using geodetic devices, automated monitoring systems and engineering seismic stations were made to study the issues of assessing changes in the dynamic characteristics of high-rise buildings and structures. To create mathematical models of deformation processes of buildings and structures, the study of interaction of structural elements of the building with the engineering-geological structure of the ground in the upper and lower parts of the megapolis was proposed. Findings. The results on ground shaking intensity acceleration, effective duration, spectral coefficients and periods of spectrum maximum are obtained. The results of measurements of vibrations on different floors of a high-rise building based on instrumental records of seismic station of local and distant earthquake have been obtained. Dependences of accelerations of shear deformations on the floor of the building with regard to engineering-geological properties of the base have been established. Predictive models of deformation processes of the building taking into account dynamic characteristics of ground vibrations and energy class of earth crust movements have been proposed. Originality. The analytical technique of correlation analysis of random variables is proposed, by means of which normally distributed linear and nonlinear processes are studied to create a mathematical model of deformation processes of buildings of different storeys. Practical value. The obtained results of the study of deformation processes of buildings and their structural elements allow to predict the dynamic model of the process of displacements of points of the structure taking into account the dynamic characteristics of ground vibrations and energy class movements of the Earth's crust

Wind-resistant reliability assessment of a super-high tower crane considering the randomness and correlation of turbulent spectral parameters

The need for wind-sensitive super-high tower cranes during the construction of high-rise structures has been growing, which makes it critical to assess the wind-resistant reliability of cranes. The accuracy of assessment is dominated by the refined simulation of real stochastic wind fields, which is usually based on the deterministic turbulent spectra including fixed spectral parameters. However, it might cause significant errors to estimate extreme responses of structures. Therefore, a simulation method for stochastic wind fields considering the randomness and correlation of turbulent spectral parameters is proposed in this study. The random functions of correlated spectral parameters are constructed based on several independent elementary random variables. A novel simulation method for stochastic wind fields involving the established random turbulent spectral functions is utilized to generate fluctuating wind samples at the Ma'anshan Yangtze River (MYR) Bridge site. In combination with the probability density evolution method, the stochastic response analysis and reliability assessment of wind-induced vibration of the crane are addressed. Results prove the effectiveness of the proposed approach in depicting probabilistic properties of real wind fields. Meanwhile, the wind-resistant comfort reliability of the tower crane is higher when considering the randomness and correlation of turbulent spectral parameters.

Research on Key Problems and Optimization Based on Structural Design of Super High-rise Buildings

At present, complex super high-rise buildings and super high-rise buildings are emerging all over China, but there are still many problems to be solved in the design of super high-rise structures. For example, the wind pressure and earthquake risk of high-rise buildings, fire safety issues and personnel evacuation issues, earthquake will produce greater inertia force and bending force in high-rise buildings, wind load and wind pressure effect will be more significant, these are the parts that need to be carefully considered to ensure the safety and stability of the building structure. Therefore, it is necessary to analyze and optimize the problem of high-rise buildings. Taking a super high-rise building in Luohu District of Shenzhen City as an example, this paper analyzes the basic structure of super high-rise building, analyzes the key problems of structural design, and discusses the optimization method. This paper puts forward the optimization design method of building structure for seismic problem of super high-rise building structure, puts forward the solution to wind resistance problem, and puts forward the optimization layout method of building fire protection.