High-rise Structures Research Articles

Effect of outrigger-belt truss system on the storey drift and maximum displacement of high-rise building

High-rise structures are becoming more common around the world, posing new challenges that necessitate ongoing technological foresight. When a structure’s height rises, it’s anticipated to have a lateral load-resisting system other than shear walls in place to negate the effect of lateral loads. However, advances in structural design and engineering have enabled building systems to withstand lateral forces such as wind and seismic stresses. There are numerous structural solutions tailored to resist lateral forces in the structure without adding to the plan area of the building to stabilize it against lateral load. The Outrigger-belt truss system is a common structural solution for successfully managing excessive drift caused by the lateral load. Hence, in this project, an attempt is made to investigate the characteristics of an Outrigger-Belt truss system. The seismic analysis is limited to the linear static method. A comparative analysis is done using STAAD Pro V8i SS6. Finally, the storey drift and maximum displacements obtained are calculated and the results are compared with the moment-resisting frame and the values are tabulated.

Seismic Comparison of Diagrid and X-Bracing System in Highrise Building

Abstract: The diagrid (diagonal grid) structural design is one of the fascinating structural design ideas for sturdy tall constructions. Diagrid, a new design style for tall, intricate structures, has emerged due to its aesthetic appeal and structural effectiveness. Diagrid's façade structural system resists both lateral loads and gravity loads by utilizing a small grid of diagonal components. As it uses less structural steel than a conventional steel frame, making the structure more environmentally friendly. This study makes use of ETABS to assess tall structures built of Diagrid steel and tall structures using different bracing techniques. Being thin makes high-rise structures extremely vulnerable to lateral forces, thus they must be constructed to provide safety and comfort in accordancewith user needs. In order to combat the lateral stresses that are most common in high-rise structures, diagrid and X-bracing systems have been created. In this study, the seismic behaviors of diagrid and X-braced systems are compared.

The correction factor of Monterey No. 0/30 sample with fines content liquefaction resistance between cyclic triaxial and cyclic hollow cylinder tests

Soil liquefaction is one of the most detrimental forms of earthquake-induced ground failure that can result in catastrophic damage to engineering structures. For the seismic safety evaluation of foundations and high-rise structures, it is the most critical way to assess liquefaction resistance. In this paper, an array number of isotropically consolidated undrained cyclic triaxial tests (CTT) and cyclic hollow cylinder tests (CHCT) have been performed to evaluate soil liquefaction resistance. Thirty-seven isotopically consolidated undrained cyclic triaxial tests and thirty-seven cyclic hollow cylinder tests were run on the uniform medium Monterey No. 0/30 sand and it is with four different percentages of fine content. By using cyclic triaxial and cyclic hollow cylinder tests for evaluating liquefaction resistance, it helps us better understand the relationship between two types of tests on uniform clean Monterey No. 0/30 sand and soil sample with five different percentages of fines content. Four different relative densities of 30%, 45%, 50%, and 60%, two confining pressure of 103 kpa and 207 kpa, and five cyclic stress ratios (0.15, 0.2, 0.25, 0.3, and 0.4) have been used for a series of cyclic triaxial tests and cyclic hollow cylinder tests. At the same relative densities of 30% and 60%, the correction factor between CTT and CHCT evaluated ranged from 0.46 to 0.63 on the uniform clean Monterey No. 0/30 sand. Statistical analyses were performed to formulate functional relationships for predicting the correction factor of soil liquefaction resistance between CTT and CHCT tests.

Seismic and damping performance of frame-distributed rocking tubes-core tube structure

In order to improve the economical deficiency of the traditional frame-core tube (FCT) structure due to the large tube area proportion, a new high-rise structure of the frame-distributed tubes-core tube (FDCT) is proposed based on the design concept of the distributed tube. Combining the distributed tubes with the rocking system, the frame-distributed rocking tubes-core tube (FDRCT) is further proposed, which aims to solve the problem of insufficient seismic capacity of the FDCT structure due to the decrease of structural stiffness. Simplified dynamic models and equations of FDCT structure and FDRCT structure are established. Frequency domain dynamic analysis and ground motion random analysis are performed based on dynamics principles, which prove that the FDRCT structure can reduce the structural dynamic response. The elastic and elastoplastic time history analysis of the FCT structure, FDCT structure and FDRCT structure are carried out by finite element simulation. FDRCT structure can make the structure deformation uniform and reduce the acceleration response, but the top displacement increases. Compared with the beam ends hinged in the FDRCT structure, the inter-story drift ratio of the structure with the beam ends fixed decreases but the acceleration increases. Increasing the mass of the distributed rocking tubes can effectively improve the seismic and damping capacity of the FDRCT structure. According to the shaking table test and the economic analysis, it is evident that the FDRCT structure can not only improve the economy of the structure, but also have better seismic and damping performance.

Practical optimal design method for multi-outrigger building structures under inter-story drift constraints

This study proposes a practical optimal design method (PODM) for high-rise multi-outrigger structures subjected to inter-story drift constraints based on the optimality criteria method. The problem is solved through two-step calculations, which avoids time-consuming iterations owing to internal-force redistribution caused by member-section modifications, multiple inter-story drift constraints and multiple outriggers. Three parameters, namely the target virtual strain energy density (VSED), section-correction factor, and structural magnification factor, are established to relate the member-section sizes to the structural inter-story drift. The influence of internal-force redistribution is considered by adjusting the target VSED and section-correction factor based on the first trial calculation results to ensure precision. The multiple local inter-story drift constraints are converted to the unforced inter-story drift constraint, whereas the optimal design problem of the structures with multiple outriggers is solved by transforming it into the optimal design problem of the key module with the strictest demand by introducing the most critical constraint criteria. Finally, the effectiveness and accuracy of the PODM are validated using a 56-story structure and 50-story seven-bay framework.

Seismic Performance of Super High-Rise Building Structure with Dual Lines of Defense Based on Response Surface Optimization Algorithm

In order to improve the safety performance of supertall buildings under earthquake, a seismic performance analysis method of double lines of supertall buildings based on a response surface optimization algorithm is proposed. Firstly, the structural performance indexes of super high-rise buildings are selected, and on this basis, the material constitutive model is constructed by the structural elastic-plastic analysis method to complete the seismic design of the first line of defense. Then, the response surface method is used to optimize the material constitutive model and complete the seismic design of the second line. Finally, the anticollapse limit state analysis method is used to determine the seismic performance of the double line of super high-rise building structures. The experimental results show that the proposed analysis method has high seismic performance, and the axial compression ratio of wall and column is always stable, in which the column is always at about 0.5 and the wall is always at about 0.26, which lays a foundation for the safety performance of super high-rise building structures under earthquake.

Experimental assessment on aseismic capacity of a perimeter diagrid concrete core structure: Shake table tests

Perimeter diagrid concrete core (PDCC) is a structural system used for high-rise building applications. Quantifying their seismic safety is of interest to owners and decision makers due to the lack of the comprehensive understanding of the seismic performance of the high-rise PDCC structure. To systematically evaluate the seismic performance, a 36-story PDCC structure has been assessed using 1/20 scaled shake table tests. In addition, a detailed nonlinear finite element model (FEM) of the PDCC structure was built for comparison and analysis with the shaking table test. The damage to the perimeter diagrid bracings, the RC structural walls, the diagonal beam, under earthquake excitations have been assessed and discussed systematically based on the experimental and numerical results. The analysis result shows that the PDCC structure has a high performance under the earthquake load that can be used as an efficient seismic force-resisting system. Under the action of horizontal earthquakes, the axial force of the diagonal braces on the same floor varies greatly, and the axial force of the diagonal brace is related to the number of other diagonal braces on its axis. In terms of seismic damage to the perimeter diagonal braces, the most severe seismic damage is concentrated in the diagonal braces with higher axial forces, while the damage to other diagonal braces with smaller axial forces is less severe. And the seismic damage of diagonal bracing has a tendency to expand to other surrounding diagonal braces.

Methodology for Predicting the Structural Response of RPC-Filled Steel Tubular Columns under Blast Loading

Reactive powder concrete-filled steel tube (RPC-FST) is a critical supporting component of large-span, high-rise, and heavy-load structures. The collapse of RPC-FST may occur under explosive load. Therefore, investigation of the dynamic response is essential for understanding the mechanisms of collapse. In this article, the numerical simulation of reactive powder concrete (RPC) adopted the modified Holmquist–Johnson–Cook (HJC) model and the modified Karagozian and Case (K&C) model. The dynamic response of RPC-FST columns under explosive load is analyzed based on arbitrary Lagrange–Euler (ALE) method. The proposed model is verified by experimental results. Results show that the modified HJC model and modified K&C model can be applied to simulate the dynamic response of RPC-FST columns under explosive load. As compared with the modified HJC model, the modified K&C model has more accurate results. This phenomenon mainly accounts for the lack of ultimate strain of RPC (EFMIN). To analyze the reliability sensitivity of RPC-FST, an efficient probability analysis method is proposed based on the Kriging model and Monte Carlo simulation (MCS). The proposed method considers five nonlinear factors, including weight and distance of TNT, height and section diameter of RPC-FST, and steel tube thickness. Finally, the sensitivity of each factor is evaluated. Results show that TNT weight greatly influences the reliability of the RPC-FST, followed by TNT distance, RPC-FST height, RPC-FST section diameter, and steel tube thickness. In addition, the RPC-FST dynamic response analysis method based on the Kriging model and MCS can improve the calculation efficiency by more than 200 times compared with the ALE method.

Establishment of deformation and subsidence monitoring baseline in the coastal environment: A case study of University of Lagos

Deformation and subsidence measurements are very vital for stability of structures and buildings. Deformation and subsidence monitoring are easily carried out with the aid of established baselines. This study focuses on the establishment of baseline for monitoring deformation and subsidence within university of Lagos. Geodetic method of control establishment was adopted, where five (5) control stations were established on stable grounds across the university of Lagos main campus with Differential GPS observation carried out on them and data obtained were processed and analysed statistically. The result of the findings shows that the baseline established is very reliable, given that the vertical controls have their relative redundancy number rij ranging between 0.1<rij<1.0 and the standard deviations ranges from 0.002 to 0.005. Also, the relative precision of the established baselines fell within the range of 7.36e-06ppm-2.54e-05ppm. From the findings of this research, deformation and subsidence studies can be reliably monitored within the University of Lagos and its environ using the baseline established through this research in order to safeguard lives and properties – including high rise structures within the university’s main campus.

Comparison of Seismic Analysis of Multi storey Buildings with RCC columns and CFST columns by Varying Heights

As there is an increase in population day by day, there is more requirement for land. But the availability of land on Earth’s surface is 29 % which should be used for various purposes and hence, there would be difficulty in providing accommodation to all the citizens. There comes the idea of vertical development of the structures i.e., multi-story structures. Usage of Reinforced Cement Concrete (RCC) for high rise structures with large spans would be very complex as it requires high grade concrete and steel and hence becomes risky. In that case, the composite structures give effective results due to the co-action of materials. Providing Concrete Filled Steel Tube (CFST) columns will reduce the requirement of formwork and will increase the functional area as the steel tube acts both as longitudinal as well as transverse reinforcement which gives mere resistance to tensile stresses. In this thesis, Multi Storied Structures of G+10, G + 20 and G + 30 were taken and variation was considered in the columns, the rest of the structural elements have been taken of RCC only. The seismic analysis of the structures has been carried out for both the type of structures for each height by using Response Spectrum analysis in Zone II following the guidelines of IS 1893:2016 code using ETABS software. The comparison of the structures has been shown in terms of earthquake response parameters such as story drift, story displacement, story shear etc. It has been concluded that structures with CFST columns have shown better seismic performance with increasing height compared to RCC structures.

Design of Earthquake Resistant Structure Using Cabkoma Strands: A Review

Abstract: Earthquakes are the indication for transformation of earth internal surface. The Indian subcontinent has suffered some of the greatest earthquakes in the world. Many research studies have been focusing on decreasing the impact of seismic waves on structures. For this initially there were many passive techniques introduced to reduce the damage caused due to earthquakes which are based on decreasing the lateral loads on structures. But since the late twentieth century the focus has shifted to introduce active earthquake techniques which are meant to absorb the seismic waves or do not let the waves propagate through the building. Though it is not possible to prevent an earthquake, the least that can be achieved in reducing the damage is to make the buildings earthquake resistant with the advancements in earthquake resistant techniques. The major goal of this dissertation is to use CABKOMA strands to create a novel earthquake-resistant technology. In this study, CABKOMA strands are used to examine the seismic response of ordinary moment resisting steel framed structures of high rise, mid-rise, and low rise analyzed with and without strands to determine the workability of cabkoma strands. To determine how well the intended structures function against earthquake motions, a comparative examination is done between them. Additionally, this work shows a comparative analysis of the seismic behavior of high-rise, mid-rise, and low-rise steel structures designed utilizing CABKOMA strands with the seismic behavior of high-rise steel structures designed using bracings an existing earthquake technique, by varying the arrangement of strands at the corner, Centre, and both centre and edge of the structures. Eventually, this work presents cabkoma strand optimization for effective strand utilization by varying strand to strand spacing from 0.5m to 1m while maintaining the same strand positioning.

Comparative Study of Shear Wall at Two Different Position by Response Spectrum Method

Abstract: Structural engineers are mainly concerned with how a structure responds to horizontal forces, and suitable stiffness is required for high-rise structures to resist horizontal forces induced by wind and earthquakes. Shear walls, which are placed to the interior of the proposed structure, are used to counteract horizontal forces such as lateral stresses caused by earthquakes and to increase the structure's stiffness. The aim of this study to compare the behaviour of shear wall at Central Internal shear wall and Outer Shear wall at the corner of G+25 high rise residential building and the nature of the building exposed to earthquakes. For obtaining result we perform response spectrum analysis on G+25 high rise building to obtain following results: storey drift, storey displacement, and storey stiffness are explored. The whole structure is analysed and modelled in seismic zone 4 for a stable structure using the programme ETABs.

Investigation of Building having Shear Wall and Bracings using Linear Dynamic Analysis

Abstract: The design and analysis of earthquake resistant structures play importance factor all over the world. Hilly regions such as Ambikapur, Koriya, Dantewada & Jagdalpur district as a part of Chhattisgarh are more vulnerable in terms of seismic collapse structure in recent years and demand of high-rise structures with irregularity as given below is increasing now day due to high land cost & infrastructure there is much need or require of earthquake stability check. The paper is about analysis of different RCC Frames along with different cases of shear wall and X-bracing. The objectives of this paper are to model the asymmetry frame with different cases in respect to location of retrofitting, to examine seismic parameters such as story shear, displacement, compressive stress, story drift in order to check stability and to validate the best suitable location for asymmetry building and finding out their limitation.

AUTOMATION OF GEODESIC MONITORING HIGH-RISE STRUCTURES

The article considers the existing methods used in the problem of geodetic monitoring of structures, analyzes the possibilities and gives a preliminary assessment of the accuracy of their use in monitoring high-rise structures. Methods have been identified that allow obtaining measurement results with a high sampling rate and have the potential for automation. Methods have been identified that allow solving the problem of calculating the daily fluctuations of a structure from the effects of solar radiation and wind load separately from the values of heel and draft.

PARAMETRIC STUDY ON TORSIONAL EFFECTS OF IRREGULAR BUILDING WITH STIFFNESS AND MASS IRREGULARITY UNDER SEISMIC ZONE

Due to the expanding population all throughout the world, there is an enormous need for the construction of high-rise structures. One of the most crucial ways to prevent damage from future earthquakes is the construction of engineering structures that are earthquake- resistant. Earthquake forces are irregular forces that may or may not cause structural damage. Failure starts in the weakest area during an earthquake. This weakness might be brought on by the structure's discontinuity in mass, stiffness, and shape. According to (IS: 18933, 2002), a story inside a building is considered to have mass irregularity only if its mass is greater than 200% of the story next to it. Average lateral stiffness or less than 70% of the stiffness in the level above. This paper presents the analysis conducted on the G+10 RC frame structure from zones II to V with mass and stiffness irregularities (response spectrum). The results show that the mass at the top floor was critical compared to other floors, whereas the stiffness at the ground floor was critical compared to other floors. Key Words: Earthquake, Response Spectrum, Mass and Stiffness Irregularity.

Общая и локальная устойчивость многоэтажных зданий при динамических и сейсмических воздействиях

The issues of general and local stability of multi-storey buildings and high-rise structures under emergency (explosions, earthquakes) loads are considered. Differential equations describing three-dimensional translational and three-dimensional rotational oscillations are given. Dependences of local and general stability estimation are obtained. A numerical example is given that takes into account local stability in higher forms of oscillation. At the same time, the behavior of a real 16-storey frame building in Leninakan during the earthquake in Spitak on December 7, 1988 is analyzed. The main causes of loss of stability and destruction are carried out.

Study of High-Rise Building with Oblique Column using ETABS

Now a days we are facing everywhere a large number of new type structural system. The oblique column is used to give an aesthetic appearance to the structure and also to determine, the effects of oblique column to the structure. It is possible with the software ETABS (Extended 3-Dimensional Analysis of Building System) to modelled and analyse the high-rise structure with oblique column. In the present study, linear static and Response Spectrum Analysis were conducted, by applying outer columns of the structure as oblique column. The plan is prepared in the software AutoCAD and modelled in the software ETABS. After Analysing, the results of the Analysis parameters such as Time period, Base shear, Storey Displacement and Storey Drift of normal column or 00 inclined column are compared with the 30, 60 and 90 inclinations of oblique column. The variation of the Results of different models are shown by the graphs.

MEMD-Based Hybrid Modal Identification for High-Rise Structures with Multi-Sensor Vibration Measurements

Although widely used in various fields due to its powerful capability of signal processing, empirical mode decomposition has to decompose signals separately, which limits its application for multivariate data such as the structural monitoring data recorded by multiple sensors. In order to avoid this shortcoming, a multivariate extension of empirical mode decomposition is proposed to deal with the multidimensional signals synchronously by employing a real-valued projection on hyperspheres. This study presents a hybrid modal identification method combining the multivariate empirical mode decomposition with stochastic subspace identification and fast Bayesian FFT methods to more conveniently and accurately identify structural dynamic parameters from multi-sensor vibration measurements. Deployed as a preprocessing tool, the multivariate signals are decomposed into several aligned intrinsic mode functions, which contain only a dominant component in the frequency domain. Then, the modal parameters can be identified by advanced fast Bayesian FFT and stochastic subspace identification directly. The combined method is first validated by a numerical illustration of a frame structure and then is applied in a shaking table test and a full-scale measurement under nonstationary earthquake excitation. Compared with the finite element method, the peak–pick, the half-power bandwidth methods, and Hilbert–Huang transform method, the results show that this hybrid method is more robust and reliable in the modal parameters identification. The main contribution of this paper is to develop a more effective integrated approach for accurate modal identification with the output-only multi-dimensional nonstationary signal.

Towards optimal design of photovoltaic/thermal facades: Module-based assessment of thermo-electrical performance, exergy efficiency and wind loads

A remarkable amount of solar energy can be harnessed for generating renewable energy by applying giant photovoltaic/thermal systems to the façades of structures. However, the applicability of these systems is overshadowed by two key parameters of building geometry and complex wind behavior. This study aims to present a clear benchmark for the applicability assessment of these systems by predicting wind complexity and identifying the position of modules with critical temperatures and wind loads prone to jeopardy and destruction. For this purpose, four hundred integrated photovoltaic modules are applied to the façade of a high-rise and a mid-rise tower with the same capacity (12000 m3) and photovoltaic façade area (600 m2), and the temperature, wind load, and thermal/electrical efficiency are studied for one by one of them. The evaluation is conducted for various wind speeds using state-of-the-art computational fluid dynamics models. The results reveal that each module undergoes different wind loads and temperatures relative to its neighboring modules and has an exclusive thermoelectrical performance in the entire system. The temperature difference among the modules exceeds 55 °C, and some modules experience operating temperatures higher than 100 °C. Based on the results, both mid-rise and high-rise structures have almost the same potential for power supply, with a maximum of 70 kW obtained at the highest wind speed, while the high-rise structure is more suitable for heating production, with a maximum of 115 kW obtained at the lowest wind speed. Therefore, more energy is produced in the high-rise tower compared to the mid-rise one. Moreover, the maximum total energy and exergy efficiencies of the system reach 33.28 % and 21.2 % in the mid-rise building and 37.05 % and 20.9 % in the high-rise building, respectively. Overall, the findings of this study give a guideline for future sustainable constructions and optimal designs of façade-based photovoltaic/thermal systems.

Parking by the bay: The supply and implications of parking infrastructure in the San Francisco Bay Area

The San Francisco Bay Area is one of the most progressive transportation regions in the deployment of high-capacity transit and the use of policies to encourage active transportation. Yet, there remains a dearth of knowledge on the abundance and location of parking infrastructure. The extent and location of parking supply, including on-street and off-street spaces, are estimated for the nine-county Bay Area by creating a federated database that joins land use, transportation, parcel, building, and parking code layers to estimate the number and characteristics of parking spaces at the census block scale. This bottom-up parking space inventory results in an estimated 15 million parking spaces in the region: 8.6 million on-street and 6.4 million off-street. Residential parking dominates the share of supply at 70%, followed by commercial at 9.4%. Space density is greatest in downtown San Francisco, Oakland, and San Jose—largely attributed to high-rise structures. On-street parking is dominant in the North Bay, commanding 78% of total parking in Napa, 75% in Solano, 68% in Sonoma, and 67% in Marin County. Parking area constitutes 7.9% of the total incorporated area. Notably, when compared to other southwest cities (Phoenix Metropolitan Area and Los Angeles County), the Bay Area parking supply appears better utilized considering spaces per person, per car, and per job. The density and quantity of parking spaces in the Bay Area are critical insights toward developing targeted policies that encourage active mobility and support affordable housing.