Tall Buildings

This report presents the work I did as part of my graduation project. It consists of designing, studying and dimensioning the JW Marriott Tower in Casablanca Marina.
Being one of the largest cities in Africa, Casablanca plans to develop its international character by enriching its heritage of skyscrapers which are the symbol of power, energy and splendour of cities.
Having a unique architecture for the first time in Morocco, the tower presents enormous difficulties in terms of design and study since they work on the limits of current standards and regulations.
In this project I present initially a dossier about towers, their construction systems and their most used materials. Subsequently I explain the final design I have developed in accordance with the architectural plans and then I present the geotechnical context of the area and define the general hypothesis.
In the study and dimensioning phase, I study the structure in two approaches: a static approach and a dynamic approach. The static approach consists in studying the static behaviour of the tower vis-a-vis the permanent the exploitation loadings before dimensioning the structural elements outside the bracing system. In the dynamic approach I study the different horizontal and vibratory stresses, starting with the wind and then the seismic calculation.
After determining these stresses, I study the seismic design of the plates and shells as well as the foundations and the retaining walls and their stabilities and justifications in accordance to the ultimate, service and accidental states.

A new approach is demonstrated to approximate computational fluid dynamics (CFD) in urban tall building design contexts with complex wind interference. This is achieved by training an artificial neural network (ANN) on local shape and fluid features to return surface pressure on test model meshes of complex forms. This is as opposed to the use of global model parameters and Interference Factors (IF) commonly found in previous work. The ANN is trained using shape and fluid features extracted from a set of evaluated principal (design) models (PMs). The regression function is then used to predict results based on shape features from the PM and fluid features from a one-off obstruction model (OM), context only, simulation. For the application of early-stage generative design, the errors (against CFD validation) are less than 10% centred standard deviation σ, whilst the front-end prediction times for the test cases are around 20s (up to 500 times faster than the CFD).

In Brazil, structural masonry is widely used in the construction of tall buildings. As the country does not have its own standard for masonry in a fire situation, the Fire Department recommends that the design of masonry structures in a fire situation be carried out in accordance with the instructions of Eurocode or similar international standard. This article critically analyses the adoption of design procedures in use in the USA, Australia and Europe for a typical Brazilian masonry structure, verifying the applicability of these codes and taking into account the differences in aggregates used in blocks and finishes, aiming to support discussions on Brazilian standardisation, in addition to comparing the different ways of approaching each standard. The results showed that it is possible to use international codes, but their use will not always portray the real situation, requiring the sector and the technical-scientific community urgently unite to address this issue.

Chapter excerpted from Vertical City: A Solution For Sustainable Living by Kellogg Wong, FAIA & Kenneth King, AIA with others. Section Three - Sustainability - Maria Sevely. Discusses current practice regarding sustainable architectural design, construction, and planning, especially in New York City. Added historical context to better understand sustainability as a concept that has been with us in the past, now given a new name and more structured approach.

The construction industry has suffered for many years from productivity losses such as delays. The continual growth in complexity of construction projects such as highrise buildings in the 21st century further aggravates the issue. Thus, the construction industry continually seeks for smarter and intelligent ways to solve existing productivity issues. This study presents a comparison of an early model (Bromilow’s Time-Cost Model) to a more contemporary approach (k-Nearest Neighbors) in predicting the construction duration of high-rise buildings. The performance of both methods have been compared by means of the correlation coefficient, root mean squared error (RMSE) and mean absolute percentage error (MAPE). Interestingly, the results showed that the predictive capability of the BTC model was comparable to that of KNN. Though, KNN performed better with correlation coefficient (0.83), RMSE (3.45) and MAPE (22.04%) compared to the BTC model with correlation coefficient (0.81), RMSE (5.05) and MAPE (22.73%) respectively. Despite the predictive capabilities of the two techniques investigated in this study, future research may seek to explore the capabilities of more powerful machine learning techniques, as well as a variety of case studies.

High-rise buildings, which have become a significant part of the urban habitat, is particularly notorious for their delayed completion times. Though, there exists a plethora of studies on construction delays, the problem however is insufficient research on prescriptive methods to mitigate delays. Thus, this study sought to employ Machine Learning (ML) techniques to learn from historical data on high-rise construction to forecast potential delay times. An input data containing 9 features, and 12 cases was used. Initially five feature sets were built based on the recursive feature elimination process. Further to that was the classification process that employs the following ML techniques: Multi-Linear Regression Analysis (MLRA), k-Nearest Neighbors (KNN), Artificial Neural Networks (ANN), and Support Vector Machines (SVM) to determine delay times. The predictive performance of these techniques was measured using their correlation co-efficient (R2) and their Root Mean Squared Errors (RMSE). The best three models according to the ML techniques used was SVM with 2 features (R2 0.56, RMSE 1.6), ANN with 2 features (R2 0.49, RMSE 1.83), and KNN with all features (R2 0.46, RMSE 1.71). To seek improvement of the predictive performance of the models developed, the three best performing models were combined using fixed and trained rules. The results showed an improvement for a fixed rule based on the minimum values with (R2 0.59, RMSE 1.65). The study has significant implications in the risk management process of high-rise projects to avoid delays. The originality is evident in that this is the first study that employs ML in predicting construction delay times.

The Future of the Skyscraper is a collection of essays, edited by SOM architects, of people outside or obliquely related to the profession of architecture to think and reflect on skyscraper design.
This approach is appealing, since the consequences of building skyscrapers with respect to their ecological, material and energy footprints are so large that the decision of their construction ought to be a larger societal question and a shared, public responsibility. In the most positive scenario this building type can help to solve problems of an increasingly urbanised and overcrowded planet: they can make cities denser, function as carbon sinks, generate energy and be used for rainwater retention and urban agriculture. If their explosive, and largely unregulated, growth is left unchecked, however, they will continue to be used to reinforce inequality and class divisions by creating privatised, heavily secured havens for the few, will continue to deplete resources, will create micro climates and heat islands, and last, but not least, will remain a massive contributor to CO2 emissions and thus speed up the process of climate change.

Tall buildings are a common sight in contemporary cities, especially in those countries where land is scarce, as they offer a high ratio of floor space per area of land. Tall buildings are also, arguably, a sign of a city"s economic stature. Tubular frames are one of the common structural systems in designing tall buildings. Framed-tube and bracedtube are the famous structural systems among other tubular frames . Designs of these frames need precise analyses. Shear lag phenomenon as an unexpected behavior of these frames should be seriously considered. In this paper we are going to investigate the solutions of reducing shear lag. A computer program written in Matlab and OpenSees will be the analyzing program. All the models in this research are steel frames. Exact wind load distribution is calculated according to ASCE 7-10. Results are illustrated in graphical formats.

Amongst the innumerable constraints that the architect faces during the design of buildings, climate probably presents one of the major forces. The climate of a region presents a set of conditions, which need to be addressed adequately in order to produce contextual buildings.  Climate-responsiveness in buildings result in comfortable, energy-efficient, environmentally friendly buildings . . . qualities that can no longer be ignored in light of the present-day global energy crisis and heightened awareness of the environmental impacts of human intervention. Buildings constructed without regard to surrounding climate can, no doubt, operate given enough energy input to correct resulting problems, whether they concern over-heating, darkness or heat loss. However, such use of active energy is wasteful, and can harm the environment. Moreover access to such energy is beyond the reach of much of the population of developing countries.
Climate-responsive buildings are those where climate considerations are involved in the decision making process, from the initial design stage, to choice of building materials, etc, till the design of all details. The trend of recent development has shifted from low to high-rise buildings due to the pressures of population in much of the world, and Dhaka is no exception. The impacts of climate on high-rise buildings differ significantly from the low-rise urban situations of the past. There are major deviations from the regional radiation regime and wind patterns in the immediate vicinity of high-rise structures, resulting in characteristic localised site climates significantly different from regional averages.
This paper examines how the climatic forces can be manipulated to provide satisfactory solutions for interiors of tall structures in tropical situations. The study concentrates on residential architecture, as being representative of 24-hour use multi-functional buildings.

During these days, tall buildings have been widely used in semi-urban and urban areas of developed and developing countries, as they provide large space for commercial or residential use. The last two decades have seen a remarkable increase in construction of residential and commercial buildings. A significant number of these buildings have been constructed in the central region. There are a number of characteristics of buildings that can have a significant influence on foundation design, including such as the building weight increases non-linearly with increasing height, and thus the vertical load to be supported by the foundation, can be substantial by soil. Since the parameters are vary from place to place or different locality of earth crust. It is necessarily to evaluate and analysed this parameters The paper consist the study and prepared the summarised report based on different past research on analysis & design of foundation, assessment on soil bearing capacity and building design requirements. The research concluded that concern on foundation design is necessary due to soil strata are varying with zone and place to place. The type of foundation depends on the building capacity and soil strata. The stability of building can be achieved with respected the SBC and foundation strength of a particular construction place.

The research examines the conflict between heritage and development in the context of a UNESCO World Heritage site (WHS). Post-industrial cities frequently try to reinvent themselves with a new city image. However, historical assets such as listed buildings or conservation areas can seemingly restrict development. At Liverpool Waters this conflict has reached a climax with UNESCO threatening to remove Liverpool's status as a WHS. This research investigates the proposed image, why it is problematic for UNESCO and what development is possible in the context of heritage. A visual analysis of Liverpool Waters identifies a hegemonic motif symbolising economic prosperity apparent in the design and highlights how its presentation can exacerbate concerns of heritage professionals. Interviews with office tenants suggest that the exterior design of the building is of low importance and therefore this motif's significance lies elsewhere. Finally, interviews with heritage professionals indicate that the design, especially the building height, is not responsive to the context nor sympathetic to the heritage. Heritage professionals explain that development is possible amongst heritage if it is sympathetic in design. The dissertation recommends an independent design review panel be established in Liverpool to audit new developments and ensure they fit well into their surroundings. Specific to Liverpool Waters it recommends that the developers forego the full realisation of the motif and scale back the design to meet UNESCO's restrictions. Overall, this publication contributes to current heritage management research by clarifying how development is acceptable in a heritage context particularly in relation to tall buildings.

The construction industry is witnessing a rapid rise in tall building projects due to an anticipated urban population explosion. However, this building typology has been subject to time overruns and total abandonment due to an underestimation of the project duration. Consequently, this paper presents the development of a model to predict the construction duration of tall building projects. In developing the model, a suite of machine learning algorithms was adopted including Multi-Linear Regression Analysis (MLRA), k-Nearest Neighbors (KNN), Artificial Neural Networks (ANN), Support Vector Machines (SVM), and Ensemble Methods. Thus, twelve models were developed in the process, and the most efficient model was selected. The procedure described in this study presents researchers and practitioners with a strategy to enhance the time performance of tall building projects through the adoption of modern digital technologies such as machine learning. The proposed model was based on an ensemble method using ANN as the combiner, with a Correlation Coefficient (R 2) of 0.69, Root Mean Squared Error (RMSE) of 301.72, and Mean Absolute Percentage Error (MAPE) of 18%.

The optimum design of tall buildings, which have a proportionately huge quantity of structural elements and a variety of design code constraints, is a very computationally expensive process. In this paper, a novel strategy, with a combination of evolutionary algorithms and machine learning methods, is developed for achieving the optimal design of tall buildings. The most time-consuming part is the analysis of tall buildings and the control of design code constraints requiring long and frequent analyses. The main idea is to use machine learning methods for this purpose. In this study, a practical methodology for obtaining the optimal design of tall building structures, regarding the constraints imposed by typical building codes, is introduced. The optimization process will be performed by a novel evolutionary algorithm, named asymmetric genetic algorithm (AGA), and in each iteration that requires checking the constraints for a large number of different structural states, machine lear...

Architecture is a physical and technical science, however it is also a social science as well. From this point of view, in this study the development of high-rise residential buildings that are presumably typology of the future built environment, are evaluated in the sense of sociologic, technologic and economic context. Depending on the environmental, social and psychological issues, advantages and disadvantages of high-rise residential buildings are discussed and recommendations for a sustainable environment are put forward.

Accumulation of growing population especially in developing countries has resulted in an increased height of buildings, this need creating impact on structural development of tall building. As building increases in height there is effect of wind and earthquake forces, to increase stiffness of building against lateral load additional structural system such as belt truss and outriggers is required. This paper presents the review of various techniques and methods used to investigate uses of belt truss and outrigger system in a tall building. The various parameters like lateral displacement, storey drift, core moment and optimum position related to outrigger and belt truss are reviewed. The reviewed approach for the design and development of tall building using outrigger and belt truss is useful to provide a potential solution. The study in turn is useful for various research persons involved in design the tall buildings by using outrigger and belt truss system.

The author presents a methodology for the design of diagrid structures based upon the systematic analysis of major buildings constructed from 2004 to the present as documented in her recent book “Diagrid Structures: Systems, Connections, Details” published by Birkhäuser in 2014. The design of diagrid towers will be demonstrated as based upon primary choices in module size, member type, node design, function of the core and the desired expression in the façade system. These translate into additional concerns of constructability and customized fabrication. Fire control systems will impact the ability to architecturally expose or conceal the steel, leading to detailing decisions.

This Dissertation is structured as a major project of spatial planning at a strategic level. It sets out the issues in addressing to the London’s skyline development. The main topic is to analyse and understand the typology of polycentric tall buildings clusters and the possibilities for the future development of tall buildings in London.

London is facing the challenge of a continuously changing skyline. This trend appears to be slow, but is surely, becoming a trend worldwide. The analysis of the particularities of London’s skyline helped to develop a scientifically constructed critical knowledge on this topic, which will continue to be of a major interest for the planning and built environment profession. In the same time the research of approaches in other cities have taken in skyline forming will help understand the strength and weaknesses of skyline development they encompass.

The goal of this report is to analyse the different international planning strategies in the process of moulding city silhouettes. As part of this learning process a broad knowledge base was formed for the diverse concepts of the vertical growth of cities, which encompassed analysing several case studies: New York City, Vancouver, Houston, Paris, Rotterdam, Frankfurt, Shanghai and Singapore. This research is focused on London as a principle study case.

In the process of examining the urban skyline, the visual and spatial impacts of tall buildings was analysed, concentrating on the planning policy, heritage impact and transport influence on the planning strategy. The overall aim of this study is to validate whether the current tall buildings strategy of London is delivering the needed development for the urban skyline. The final conclusions will state the possible concepts in forming successful typology for the London’s urban skyline and make recommendations for future potential development.

This Steel Technical Information and Product Services (Steel TIPS) report provide information on blast resistance and protection of steel and composite building structures against an intentional or accidental explosion occurring close to the building.  Chapter 1 gives a background on the issues of blast-resistance and blast protection and introduces the reader to the current status of this important and rapidly developing field. Chapter 2 discusses the  blast effects on humans and structures and provides a summary of blast loads used in blast resistant design. Chapter 3 provides information on material properties of steel and concrete under a high strain rate of the blast. Chapter 4 focuses on the discussion of the performance of specific steel and composite members and connections with an emphasis on the primary members such as beams, columns, and floors as well as the connections directly subjected to blast pressures. The non-structural elements are not part of this report. In addition, Chapter 4 provides some suggestions on how to improve the detailing of steel and composite members to attain better performance under blast loads. There is a bibliography listing for further reading.

The first two decades of the twenty-first century represent a major milestone in skyscraper developments. By analyzing extensive data, the research presented here contrasts building activities of skyscrapers before and after the turn of the 21st century. It examines tall buildings in the world’s major continents (Asia, Europe, North America, Oceana, Middle East, South America, Central America, and Africa) and their respective cities including Shanghai, Beijing, Shenzhen, Bangkok, London, Moscow, New York, Chicago, Miami, San Francisco, Melbourne, Sydney, Dubai, Doha, Riyadh, Tel Aviv, São Paulo, Panama City, Mexico City, and Nairobi. By using nearly 40 tables and 80 maps, the paper highlights the rapid activities of building significant skyscrapers at greater heights, elucidates the changes in functions and services, and delineates shifts in spatial patterns and visual impact.

PEER has just published Report No. 2017/06 titled: “Guidelines for Performance-Based Seismic Design of Tall Buildings,” Version 2.03, prepared by a TBI Working Group led by co-chairs Ron Hamburger and Jack Moehle: Jack Baker, Jonathan Bray, C.B. Crouse, Greg Deierlein, John Hooper, Marshall Lew, Joe Maffei, Stephen Mahin, James Malley, Farzad Naeim, Jonathan Stewart, John Wallace.

In the time since the publication of the 2010 Guidelines, the profession has gained substantial experience in application of performance-based techniques to design buildings around the world, and, in particular, the western United States.

This second edition addresses lessons learned in application of the first edition on many projects and the conditions, knowledge, and state-of-practice that presently exist.

The turn of the last century saw a surge in the construction of high-rise buildings. The surge created a demand for performance-based approaches to enable construction using new framing systems rising to heights outside the range of building code prescriptive provisions. The Pacific Earthquake Engineering Research Center (PEER) responded to this need by leading an initiative to develop design criteria that will ensure safe and usable tall buildings following future earthquakes. Download the primary product of this initiative: Guidelines for Performance-Based Seismic Design of Tall Buildings.

Collectively known as the Tall Buildings Initiative, this project involves the Applied Technology Council, Federal Emergency Management Agency, Los Angeles Department of Building and Safety, Los Angeles Tall Buildings Structural Design Council, California Seismic Safety Commission, San Francisco Department of Building Inspection, Southern California Earthquake Center, Structural Engineers Association of California, U.S. Geological Survey, PEER, and several practicing professionals.

This article traces the holders of the superlative title “Tallest Building in The Bronx” from the late nineteenth century until the present day - 2018. After first establishing the criteria for defining what constitutes a “building” and how height is measured for this purpose, each of the holders of the title are identified, described, and placed into the broader historical context. In addition, since the definition of “tallest building” has not always been a matter of unanimous consensus, there are several Bronx buildings that have been described as being the borough’s tallest, but which based on the criteria outlined herein do not qualify for the accolade. Nevertheless, such “pretenders” to the title are also acknowledged given their presumptive status.

The Bronx has not been known for its tall buildings. This is especially true compared to neighboring Manhattan, which is celebrated the world over as one of the great skyscraper meccas. Little consideration has been given to The Bronx’s tall buildings. Indeed a primary purpose here is to fill in a gap in the literature -- while lists of the tallest buildings are readily available for not only Manhattan but many localities, no such tabulation seems to have been compiled for The Bronx. For the record, this study offers the definitive answer to the question: what have been the tallest buildings in The Bronx?

Finite Element Analysis of the tall slender RC structure with RC shear wall, Steel Plate Wall, Bracings And without any lateral force resisting system has been carried out to study. The behavior of tall RC structure in terms of time period, base shear, Mode shape, story displacement & story drift. Due to Application of various Time history Earthquake loading is studied. The three dimensional model has been considered and analyzed for the gravity loading, seismic loading, for seismic loading both Response spectra Method and Time history Method has been carried out IS 1893:2002 has been used for seismic loading calculation and analysis.

CASE STUDIES FOR SPECIAL INVESTIGATIONS

Lateral Loads

                      Seismic
                                      Site specific response spectra

                      Wind
                                        Wind tunnel report and TLD

Much of the anticipated future growth in North America will occur in suburbia. The critical challenge that we will face is how to accommodate this growth in a sustainable and resilient manner. While the past 50 years have been characterized by suburban sprawl and low-rise development, “suburban sustainability” is increasingly making its way into the planning and urban design policy realm. This research investigates the spatial patterns of tall buildings in 24 suburban communities of three different regions including, Washington, D.C., Miami, and Chicago. The study identifies 10 different spatial patterns that prevail in suburbia and provides a concise summary of these patterns and reflects on their spatial and urban design aspects. The research concludes that the Tall Buildings and Transit-Oriented-Development (TB-TOD) model, an urban design approach that refers to vertical mixed-use clusters centered on mass-transit nodes, is one of the sustainable options for large regions going forward. The paper also discusses the challenges to the TB-TOD model implementation, mainly
limited transit lines and community resistance. It ends by offering directions for future research.

Ante la cuestión de Cuáles son los mecanismos que nos permiten excluir lo que puede tornarse inconveniente en el ámbito de la cultura arquitectónica local surge la pregunta por la relación entre Arquitectura y Técnica en las revistas de arquitectura. Entendiendo a dichas publicaciones especializadas como un medio determinante de validación de la obra en el ámbito disciplinar.
¿Se aleja la técnica del ámbito de la concepción del proyecto de arquitectura a partir de los años 60? ¿Es posible reconocer este fenómeno en las publicaciones que dominan el paradigma del período mencionado?
¿Es la Revista Construcciones, la Revista de la Cámara Argentina de la Construcción(1), una revista marginal para la cultura arquitectónica?.
(La Cámara Argentina de la Construcción Surge en el año 1936 y la publicación en papel de la revista dura hasta fines de los años 80´s.)
Me propongo revisar la forma de mostrar los proyectos de arquitectura en altura, torres,  publicados entre el año 1960 y 1975 en dicha revista. 
¿Qué Arquitectura Muestra la Revista Construcción? ¿De que manera lo hace? ¿Es posible determinar un carácter propio y otra forma de ver la arquitectura en esta publicación secundaria?
¿Era esta revista leída por los arquitectos? ¿Cuál es la real difusión que tenía entre los arquitectos? Finalmente, ¿Podemos encontrar en la forma de mostrar estos proyectos un campo de trabajo que nos permita rever el campo de batalla del proyecto arquitectónico contemporáneo?

Buenos Aires’  First concrete skyscraper, the Galería Güemes, achieved several innovations. Inaugurated in December 1915, the Galería Güemes, by the Piedmontese Francesco Gianotti, combines the Parisian (or Milanese) commercial gallery type with a 14-story, multipurpose skyscraper. The structure of the complex—which includes pillars, vaults, suspended and pivotal  floors—is made of reinforced concrete, making it one of the early tall buildings using this technology, and the  first for the gallery-skyscraper building typology. However, the Galería Güemes is not only a pioneer in a technical respect, it also represents typological and functional innovations. The tower emerges from a 116-meter-long monumental galleria that opens to the city as public space. Reflecting both metropolitan life and European architectural aspirations, the building houses, among other elements, a cabaret, a theater, o ces, Roman baths, residential apartments, a restaurant, and an observation terrace.

The outrigger systems, which is widely used with shear wall-framed systems at the tall buildings, increase the lateral stiffness of the structural bearing system and reduce the lateral drift of the structure under lateral loads. However, the traditional outrigger systems, besides these positive contributions, also create some limitations and problems affecting the modeling of the structure. Some of these; more interior space occupying as an architect, problems arising in the connection of outrigger and center core (especially when a concrete shear-wall core is used). On the other hand, the belt trusses known as "Virtual Outriggers" which have recently been used to build high-rise structures, have removed these problems. Unlike the traditional outrigger systems, belt trusses are formed between the outer columns. In this way belt trusses eliminate the problems arising from the direct connection of the outriggers to the center core and other problems associated with using outriggers. Extensive studies have been carried out on the examination of outrigger and belt truss systems used in high-rise buildings under static and dynamic loads. In this study, the linear earthquake responses of three structural models, which are shear wall-framed system, shear wall-framed system with traditional outriggers and shear wall-framed system with belt trusses, were performed by using modal time history analysis method. Lateral displacements and drifts of the structure, internal forces of the structural elements were obtained. These results of three structural models were compared with each other and the effectiveness of outrigger and belt truss systems were assessed. For earthquake input, three real earthquake records were selected. These records were scaled in accordance with the DD2 level earthquake design spectrum defined in Turkish Building Earthquake Standards (2018) and used in the analyses.

El desarrollo de  de estructuras de hierro y acero significó el inicio de un progresivo proceso de crecimien-to en altura de las edificaciones. La especialización de zonas de las ciudades, particularmente en las ciudades americanas, como áreas reservadas a los negocios, y la apa-rición de edificios de oficinas, junto al crecimiento de los precios de los terrenos, prepararon las bases para el desarrollo de una nueva tipología de edificios altos: el rascacielos. Los nuevos conocimientos científicos, avances técnicos en la construcción, nuevos materiales, accesorios y equipos, así como los requerimien-tos derivados del desarrollo del aparato productivo, motorizarán el desarrollo de la tecnología de edi-ficios altos. Ese proceso de cambio técnico se revisa en este artículo. Tecnología y consTrucción. Vol. 15-2, 1999, pp. 7-24. recibido el 11/06/99-acepTado el 30/10/99 DESCRIPTORES: Construcción; Innovación; Rascacie-los; Cambio técnico. a b s T r a c T The development of iron and steel structures meant the beginning of a progressive process of growth in the height of the buildings. The specialization of areas of the cities, particularly in the American cities, as reserved areas to the business, and the appearance of the office building, just as the increment of the prices of urban land, prepared the bases for the development of a new type of high buildings: the skyscraper. The new scientific knowledge, the tecnical advances in construction, new materials , accesories and equipment, as well as the derived requirements of the development of the productive sector, will motorize the development of the tecnology of tall buildings. That process of technical change is revised in this article. e D i F i c i o s (m u y) a l T o s : los rascacielos alfredo cilento sarli T e c n o l o g í a y c o n s T r u c c i ó n 15 ii i n T r o D u c c i ó n La evolución en altura de las edificaciones, a partir de la introducción de las estructuras de acero, puede ilustrar cómo, a lo largo de la historia, el proceso de inno-vación en la construcción ha estado condicionado, por el lado de la oferta, por la aparición de nuevos conocimientos científicos y técnicos, nuevos materiales, nuevos equipos y artefactos; y, por el lado de la demanda, por las nuevas necesidades derivadas de la evolución del entorno socioeco-nómico y político, por los requerimientos del desarrollo del aparato productivo, por exigencias ambientales; y también por las ambiciones y vanidades de individuos e instituciones públicas y privadas, que llevaría a la competencia, que dura hasta hoy, por construir el "edificio más alto del mundo". El análisis del desarrollo del skyscraper-el rascacielos-es un buen ejemplo para ilustrar ese proceso de evolución tecnológica que permitió a los seres humanos alojarse, trabajar y divertirse, dentro de estructuras artifi-ciales, al nivel de las nubes: el sueño de L. S. Buffington. Éste era un joven arquitecto de Minneapolis, que había soñado con estructuras de esqueleto de acero desde 1880, inspirado en escritos de Violet le Duc, que varios años an-tes había señalado que "Un arquitecto práctico no podría concebir forzosamente la idea de erigir un gran edificio cuya estructura fuese enteramente de hierro, recubriendo y preservando ese esqueleto por medio de un envoltorio de piedra". Buffington, inspirado en esa lectura, soñó con edificios de veinte, treinta, cincuenta e incluso centenares de pisos, e hizo fantásticos croquis, de los que llamó cloud-scrapers, es decir, "rascanubes". Inclusive hizo "cálculos de IlustracIones del arq. ramón león

People often take building age as a proxy for building performance, and thus equate old buildings with decrepit buildings. In Hong Kong, a number of public policies also use building age as a criterion to screen off eligible applications for subsidies. The belief in the conveyance of information on building performance by building age rests on the traditional wisdom that building fabrics and building services will wear and tear and ultimately become obsolete over time. However, if building maintenance and management is in place, it is uncertain how much information building age can still convey. There has seldom been any empirical test in this regard, due to the lack of an objective method to quantify building performance. This paper aims to fill this gap by examining the relationship between building age and its performance in respect of health and safety based on results from a standardized assessment of the health and safety conditions of 134 residential buildings in Hong Kong. Our preliminary results confirmed that there was a significant negative relationship between building age and its health and safety conditions. However, the 20-year cutoff adopted in most public policies was not supported by the empirical results. In addition, we analytically show that the use of building age as a decision tool for resource allocation may lead to inefficiency, and accordingly propose three solutions.

This article examines recent high-rise developments in Tokyo that have reshaped the mega-city's identity,
and in particular denes the timeline of these drastic changes on the skyline. The research has focused on
buildings over 150 m tall in Central Tokyo, considering construction data in light of the city's historical
development, economic models, legal framework, and technological restrictions. The objective of this
research is to explain the processes that have led to the current skyline, and in particular explain the historical
reasons that have led to what is often described as Tokyo's chaotic morphology.

A probabilistic procedure for the Performance-Based Design of structures subject to wind action is illustrated. The central objective of the procedure is the assessment of the adequacy of the structure through the probabilistic description of a set of decision variables DVs. Each DV is a quantitative measure of a specific structural performance (no collapse, occupant safety, accessibility, full functionality, limited displacements or accelerations, etc.). The structural risk is conventionally measured by the probability of exceeding a relevant value of the corresponding DV; the probability is evaluated by taking into account the Aeolian hazard at the site, the calculated structural response and damage, and the correlation between the attained damage level and the relevant DV. The procedure is applied to an example case: the assessment of the comfort requirement for a high-rise building.

► A kind of Elastic Composite, Reinforced Lightweight Concrete (ECRL.C) with the mentioned specifics is a type of "Resilient Composite Systems (RCS)" in which, contrary to the basic geometrical assumption of the flexure theory in Solid Mechanics, "the strain changes in the beam height during bending" is typically "Nonlinear". (The RCS could be counted as "The Methodically Reinforced Nonlinear Porous Materials", also having the high specific modulus of resilience in flexure.)

♦ Through employing this integrated structure, with significantly high strain capability and modulus of resilience in bending, we can achieve the high bearing capacities in beams with the secure fracture pattern, in less weight.

♦ Due to the system particulars and its behavior in bending, the usual calculation of the necessary equilibrium steel amount to attain the low-steel bending sections with the secure fracture pattern in the beams and its related limitations do not become propounded. Thereby, the strategic deadlock of the high possibility of the brittle fracture pattern in the bending elements made of the usual reinforced lightweight concretes, especially about the low-thickness bending elements as slabs, is unlocked.

♦ This simple, applied technology and the related components and systems can have several applications in the road and building industries. (It can also be used in making the resilient pieces and constructions "with appropriate behavior and high resistance against severe blasts and shocks.)

♦ Regarding the "strategic importance of Lightweight and Integrated Construction in the practical increase of the resistance and safety against earthquake" and considering the appropriate behavior of this "resilient", durable structure against the dynamic loads, shakes, impacts, blasts, and shocks and the possibility of making some lightweight and insulating, non-brittle, reinforced sandwich panels and pieces, this resilient system and its components can especially be useful in the "seismic areas".

♦ This system can also be employed in constructing the vibration and impact absorber bearing pieces & slabs, which can be used in the "Railroad & Subway Structures" too.

♦ Here, the "Resilient Composite Systems (RCS)" and particularly, the ECRLC as a type of the RCS have been concisely presented. [By the way, an instance of the said new structure and its components and the results of some performed experiments (as bending loading and compressive loading of the slabs made of this structure, similar to ASTM E 72 Standard) have been shown in the related pictures & figures.]
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/ ● Key Words: Strength of materials (solid mechanics), Civil (construction), Materials, Earthquake (resistance and safety), Resilient concrete (flexible concrete, bendable concrete, elastic concrete), Composite concrete, Lightweight concrete, Reinforced concrete, Fibered concrete, Lightweight and integrated construction, Rail (railroad, railway), Subway, Road, Bridge, Resilience, Energy absorption, Fracture pattern, Non-linear, Strain changes, Beam, Ductility, Toughness, Insulating (insulation), Thin, Slab, Roof, Ceiling, Wall (partition), Building, Tower, Plan of mixture, Insulating reinforced lightweight pieces, 3d, Sandwich panel, Dry mix, Plaster, Foam, Expanded polystyrene (EPS), Polypropylene, Pozzolan, Porous matrix (Pored matrix), Mesh (lattice), Cement, RCS, ECRLC
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/ ► Contents:
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* ABSTRACT
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* I. INTRODUCTION
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* II. WHAT ARE THE RESILIENT COMPOSITE SYSTEMS
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- A. General Review
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- B. Components
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. - 1) Mesh or Lattice
. - 2) Fibers or Strands
. - 3) "Matrix" With the Suitable Hollow "Pores (Voids)" and/or "Lightweight Aggregates" in its Context
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- C. More Explanations About the RCS
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- D. Why Are These Systems Called "Composite"?
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- E. The General Structural Particulars and Functional Criteria as the Necessary Specifications of the Compound Materials Generally Called "Resilient Composite Systems"
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. - 1) General Structural Criteria
. - 2) Functional Criteria (Required Specifications)
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* III. "ELASTIC COMPOSITE REINFORCED LIGHTWEIGHT CONCRETE (ECRLC)" AS A TYPE OF THE RESILIENT COMPOSITE SYSTEMS (RCS)
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- An Instance of the Lightweight Concrete That Could be Used in Making the ECRLC
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* IV. REVIEW OF SOME EXPERIMENTS, AND MORE DESCRIPTION ABOUT ECRLC
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* V. SUPPLEMENTARY ELEMENTS
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* VI. APPLICATIONS
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* VII. FINAL REVIEW
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* ACKNOWLEDGEMENTS
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* REFERENCES 
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***
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/ ● General Review:
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• A kind of "Elastic Composite, Reinforced Lightweight Concrete" with the said specifics is a type of the "Resilient Composite Systems (R.C.S.)" in which, contrary to the basic geometrical assumption of flexure theory in the Solid Mechanics, the strain changes in the beam height during bending is typically "Non-linear".
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• Indeed, the RCS, as the Elastic Composite, Reinforced Lightweight Concrete (ECRLC), do not behave as most of the solid materials in bending.
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• In the "Resilient Composite Systems", distributed pores and/or appropriate lightweight aggregates or beads, accompanied by the reticular structure of the strengthened conjoined matrix, bring about the expedient internal shape changes during bending and continuing the elasticity in bending with the said nonlinearly pattern. This means better distribution of the stresses and strains and better utilizing the potential capacities of the employed reinforcements in bending and tension; whereas, in the usual lightweight concretes for instance, distributed hollow pores (such as the gas bulbs in the cellular concretes) or lightweight aggregates (such as Plastic, Rubber or polystyrene beads or any other kind of lightweight aggregates such as Perlite and Vermiculite) decrease the modulus of resilience in bending and could increase "the possibility of beam fracture of brittle and primary compressive type" in bending (compared to the concrete with higher density) according to the case.
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• In this way, by using the mentioned method to make the said particular composite systems, we could considerably increase the modulus of resilience and bearing capacity in bending "together with" significant decrease of the weight and also the possibility of beam fracture of primary compressive type. Through making these particular integrated functioning systems, for the first time, the said (paradoxical) properties have been concomitantly fulfilled in "one functioning unit" altogether.
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• Respect to the special pattern of the strain changes during bending in the particular Resilient Composite System termed ECRLC, this system as an integrated functioning unit with the reticular arrangement and texture has more strain capability (particularly within the elastic limit), energy absorption and load bearing capacities in bending compared to the usual reinforced concrete beams.
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• Thereby, through employing this applied structure, solving some of the main problems in lightweight concretes application, especially the deadlock of brittle and insecure being of fracture pattern in many of the usual reinforced lightweight concrete structures, is provided; reaching to the high bearing capacities in bending elements (even with low dimensions & weights) is to hand, and getting access to a simple and practical opportunity for "qualitative development of possibilities of using lightweight concretes" (especially with oven-dry densities of < 1350-1400kg/m3 and compressive strengths of <14-17mpa, and even with oven-dry densities of < 800kg/m3) is conceivable.
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• Naturally, by more studies in the field, these structures and their applications in various fields could be developed more.
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/ ► FULL TEXT (Open Access):
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- http://arxiv.org/abs/1510.03933 
( https://arxiv.org/ftp/arxiv/papers/1510/1510.03933.pdf ) ;
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. Kamyar Esmaeili: "Elastic Composite Reinforced Lightweight Concrete as a Type of Resilient Composite Systems";
The Internet Journal of Innovative Technology and Creative Engineering (IJITCE); 2012; 2(8): 1-22.
- http://ia800305.us.archive.org/34/items/IJITCE/vol2no801.pdf [Also archived at: http://www.webcitation.org/6B2pFPpBh ] ;
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- https://www.scribd.com/doc/11530978/Elastic-Composite-Reinforced-Lightweight-Concrete-ECRLC-as-a-type-of-Resilient-Composite-Systems-RCS-http-arxiv-org-abs-1510-03933 ; 
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- https://sites.google.com/site/NEWSTRUCTURE1 ;
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- https://sites.google.com/site/newstructure1/publications-page/ELASTIC%20COMPOSITE%2C%20REINFORCED%20LIGHTWEIGHT%20CONCRETE%20AS%20A%20TYPE%20OF%20RESILIENT%20COMPOSITE%20SYSTEMS.pdf ;
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- http://www.pdf-archive.com/2015/09/22/elasticcomposite-reinforcedlightweightconcreteasatypeofrcs/elasticcomposite-reinforcedlightweightconcreteasatypeofrcs.pdf ;
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- The link to the document in PDF format on this site:
file:///C:/Users/pc5/Downloads/ELASTIC_COMPOSITE_REINFORCED_LIGHTWEIGHT.pdf ;
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- ...

The present construction practice of high raise buildings, mostly adopting beam column slab (BCS) moment resistance framed system. From the observations of recent happenings, geographical changes are rapidly happening in India, causing high floods, cyclones and earthquakes which seriously influencing the performance of tall structures. Shear wall flat slab system (SWFS) is recent advancement in the construction of tall structures, where the system provides an efficient structural configuration to distribute lateral loads through shear walls and flat slab. Even the performance of SWFS system is well established in the design of tall buildings, a limited scope of studies are made against economic viability. This paper discussed about the relative cost-benefits and material consumption of SWFS system compared with BCS framed system, in a reinforced concrete multi storied buildings. The proposed 18 storied residential building located at Visakhapatnam (seismic zone-II) of Andhra Pradesh India and the design followed by ETABS software. The study concludes that SWFS system is economically viable than BCS frame system and the cost of construction and material consumption are relatively 3% less in SWFS system. Hence the designers need to promote SWFS system for better performance and economic viability of tall buildings.

A stiffness-based methodology for the preliminary sizing of the braces and support columns of a steel bracing system is discussed. The methodology applies to the case of tall earthquake-resistant buildings, whose dynamic response is significantly influenced by global flexural drifts and higher modes of vibration. The preliminary sizing of the structural members of several versions of a bracing system for a twenty four-story building is carried out. From the evaluation of the dynamic characteristics of the different versions of the bracing system, it is concluded that the proposed methodology results in adequate stiffness-based sizing during the performancebased preliminary design of tall braced buildings.

The performance of structures especially of buildings during strong earthquakes is a matter of great concern, both in terms of structural damage and public safety. The traditional methods of structural design specified in building codes are mostly prescriptive and implicit in nature. There is a general acceptance in the structural engineering profession that such prescriptive and implicit design need to be evaluated and augmented by more explicit and reliable methods that can determine the performance of specific structures for particular seismic hazards and compared against well defined and measurable objectives. This paper presents the overview of performance based design procedures including pushover methods and full nonlinear time history analysis approaches applicable to tall buildings. The paper also presents several case studies in which the seismic performance has been evaluated using site specific ground motion and nonlinear time history analysis both for Design Basis Earthquake (DBE) and Maximum Credible Earthquake (MCE). Some of performance evaluation is for existing buildings and some as part of the process for design of new buildings. Most of the buildings are located in the Philippines and are in the range of 19 to 70 storeys in height.

Tall buildings are subjected to horizontal movement or deflection under the impact of earthquake loads. To prevent lateral movement of the structure, the structure should be rigid enough to support the lateral load. The bracing system is a system provided to minimize the lateral deflection of the structure. The members of the braced frame are subjected to tension and compression, so they are provided to withstand these forces similar to a gantry. Different types of bracing approaches are applied according to the mechanism. The Articles deals with comparative study of different types of bracing using a G+15 Storey. The plinth area taken as 30m x 24 m (rectangular section pattern) i.e. 720m 2. The Structural parameters are used in three different stage levels which storey as per the need of the structure. The earthquake response can evaluate by using response spectrum method into it. The zone V. Etabs software mechanism is used for the modelling and analysed by Response Spectrum Analysis. To Analysis of structure based on varying the bracing types such X, V and combination of both are used in model 2 to 4. Model 1 taken as reference model as a rigid frame structure. Model 5 is Resisting Frame with shear wall System. The final conclusion made such that model 4 is the safest and most economical from the all the five models analyses Keywords: Tall Buildings, X, V Bracing, zone V, Response Spectrum Method, Etabs software I. INTRODUCTION During earthquake motions, deformations take position across the elements of the weight-bearing method as a result of the response of constructions to the ground motion. Because of these deformations, interior forces boost across the factors of the load-bearing approach and displacement behaviour seems across the building. The consequent displacement demand varies relying on the stiffness and mass of the constructing. As a rule, buildings with higher stiffness and diminish mass have smaller horizontal displacements demands. On the contrary, displacement needs are to increase. Then again, every building has a specific displacement potential. In different words, the quantity of horizontal displacement that a building can have the funds for without collapsing is restricted. The reason of strengthening ways is to ensure that the displacement demand of a constructing is to be kept beneath its displacement potential. It will most commonly be finished by means of decreasing anticipated displacement demand of the constitution for the period of the strong motion or improving the displacement ability of the constitution. To oppose lateral earthquake loads, shear dividers are normally utilized in RC confined structures, while, steel propping is the regularly utilized in steel structures. In the previous two decades, various reports have likewise demonstrated the compelling utilization of steel propping in RC outlines. A Bracing is a system that is provided to minimize the lateral deflection of structure. The members of a braced frame are subjected to tension and compression, so that they are provided to take these forces similar to a truss A braced frame is a structural system commonly used in structures subject to lateral loads such as wind and seismic pressure. The members in a braced frame are generally made of structural steel, which can work effectively both in tension and compression. The beams and columns that form the frame carry vertical loads, and the bracing system carries the lateral loads. The positioning of braces, however, can be problematic as they can interfere with the design of the façade and the position of openings. Buildings adopting high-tech or post-modernist styles have responded to this by expressing bracing as an internal or external design feature.

This paper presents a brief understanding of the concept of Outrigger system and explains its structural composition, Nowadays, in modern tall buildings, lateral loads induced by wind or earthquake forces are often resisted by a system of multi-outriggers. An outrigger is a stiff beam that connects the shear walls to exterior columns. When the structure is subjected to lateral forces, the outrigger and the columns resist the rotation of the core and thus significantly reduce the lateral deflection and base moment, which would have arisen in a free core. During the last three decades, numerous studies have been carried out on the analysis and behavior of outrigger structures. But this question is remained that how many outriggers system is needed in tall buildings, This paper deals with the comparison of core building without outrigger, with single outrigger and double outrigger

This research studies the interrelation between the integrated architectural design of high-rise buildings and the limitations addressed by the structural and auxiliary systems added to attain the safety regarding the resistance of lateral forces, and it aims to render an optimized solution of local high-rise buildings compatible with the climate and seismic regions of Damascus city.

Since land is scarce in metropolitan locations, it's common for tall building to be erected in C form. With the use of software ETABS 2019, this study examines the features of wind-induced story displacement and story drift operating on tall Cshaped models, with and without shear wall. Also, empirical formulae are used for manual calculations and to obtain the wind force and designed wind pressure on C-shaped tall building using codal provisions of IS 875 (Part 3) : 2015, also its applicability has been validated by a case study. For tall C-shaped buildings, this study gives a comparative result on the effect of wind load on building, with & without shear wall on behalf of maximum story displacement and story drift.

In response to the global drive towards sustainable construction, cross-laminated timber (CLT) has emerged as a competitive alternative to other construction materials. Despite the construction of CLT buildings up to 10 storeys in areas of low seismicity, few multi-storey CLT buildings have been constructed in areas of moderate to high seismicity due to lack of knowledge regarding their performance under lateral loading. Previous experimental studies of the behaviour of CLT wall systems under lateral loading have been limited to replicating the conditions within multi-storey buildings with approximately three storeys, and most wall systems tested replicated ground floor wall systems. To develop an understanding of how taller CLT buildings would behave under lateral loading, for the first time, testing of CLT wall systems replicating conditions within buildings taller than three storeys was undertaken. In this study, wall systems representative of those within a 10 storey CLT building were experimentally tested; an above ground floor wall system was subjected to monotonic lateral load and constant vertical load, with vertical loads replicating gravity loads at storeys within a 10 storey CLT building. The results obtained suggest variable behaviour of wall systems throughout multi-storey CLT buildings, with lateral movement becoming significant at higher storeys.