Design Of Multi-storey Buildings Research Articles

Optimum spanning for rectangular floor systems – part 2: an algorithm and practical applications

In practice, structural optimum geometric design consists of selecting the best combination of a finite number of structural elements and available parameters. It gives the optimum design procedure a combinatorial nature. In this paper, first a bi-objective combinatorial optimisation problem is formulated for the floor spanning design of multi-story buildings. The aim is to achieve an optimum spanning of rectangular reinforced concrete (RC) floor systems with the minimum cost and plan eccentricity. Two popular types of floor systems are studied: flat plates and beam-slab floor systems. Then a bi-objective Ant Colony Optimization approach, as a robust algorithm for discrete optimisation, is developed to solve the combinatorial optimisation arisen from the optimum geometric design of reinforced concrete floors. Numerical Examples are included to demonstrate the application of the methodology and robustness of the algorithm.

Cost efficiency analyses of steel frameworks for economical design of multi-storey buildings

In the present study cost efficiencies of various steel frameworks are investigated for economical design of multi-storey buildings. A total of thirteen steel frames that incorporate various types of beam-column connection and bracing configuration are considered for detailed and comparative cost analyses. The three multi-storey buildings consisting of 10, 20 and 30 floors are stiffened according to each of the thirteen steel frameworks to yield thirty-nine test frames for numerical applications. First design optimizations are carried out using an evolution strategy (ES) integrated parallel optimization algorithm to minimize the total member weight in each test frame. An extensive cost analysis is then carried out on the optimized design of each test frame to calculate its estimated construction cost using a cost model that itemizes costs of all production stages including material, manufacturing, erection and transportation. Cost-efficient frameworks are identified for the three steel buildings by comparing estimated costs of the test frames. Furthermore, the variations in cost efficiencies of the steel frameworks versus the storey number (or building height) are scrutinized. The results collected are utilized to reach certain recommendations regarding the selection of economically feasible frames for design of multi-storey steel buildings.

Bounded Disturbance Amplification for Mass Chains with Passive Interconnection

This paper introduces the problem of passive control of a chain of N identical masses in which there is an identical passive connection between neighbouring masses and a similar connection to a movable point. The problem arises in the design of multi-storey buildings which are subjected to earthquake disturbances, but applies in other situations, for example vehicle platoons. The paper studies the scalar transfer functions from the disturbance to a given intermass displacement. It is shown that these transfer functions can be conveniently represented in the form of complex iterative maps and that these maps provide a method to establish boundedness in N of the H-infinity norm of these transfer functions for certain choices of interconnection impedance.

DESIGN OF MULTI STOREY BUILDING RESTING ON SINGLE COLUMN

The aim of the project is to analyze and design of multi-storey building resting on the single column by using different code provisions. A lay out plan of the proposed building is drawn by using AUTO CADD 2010.The structure consist of ground floor plus five floors, each floor having the one house .Staircase must be provides separately. The planning is done as per Indian standard code provisions. The building frames are analyzed using the various text books. Using this so many standard books analysis of bending moment, shear force, deflection, end moments and foundation reactions are calculated. Detailed structural drawings for critical and typical R.C.C. members are also drawn. Co-ordinates for all structural members are tabulated for ready reference.

Building Design and Construction Process Influence in Construction Waste Generation

The amount of construction waste (CW) at building sites is highly variable, for instance the CW generation index ranges between 50-300 dm3 per square meters of gross floor area. Today there is still a lack of knowledge about variables (building design, construction process, construction technologies, etc.) affecting the CW generation. The objective of this paper is to analyse the influence of multi-storey building design and some construction processes on the CW generation indexes. The CW generation was analysed for two groups of buildings with two different construction processes; one with plumbing and electric services installed inside the masonry element and the other with plumbing and electric services installed onto the masonry element and covered with water-resistant drywall system (reducing the construction waste generation). The gross floor area directly affects the amount of executed construction works in a building site. Since the most important works (concrete, masonry and cladding) for CW generation is related to gross floor area, gross floor of buildings is also directly related to CW generation. For buildings with gross area varying from 20,000 to 80,000 m2, there is a reduction of approximately 18% of construction waste only changing the plumbing and electric services installation system, from embedded in the masonry element to installed onto the masonry element and covered with water-resistant drywall system.

Analysis of settlements of space frame-shear wall-soil system under seismic forces

The importance of considering soil-structure interaction effect in the analysis and design of RC frame buildings is increasingly recognized but still not penetrated to the grass root level owing to various complexities involved. It is well established fact that the soil-structure interaction effect considerably influence the design of multi-storey buildings subjected to lateral seismic loads. The shear walls are often provided in such buildings to increase the lateral stability to resist seismic lateral loads. In the present work, the linear soil-structure analysis of a G+5 storey RC shear wall building frame resting on isolated column footings and supported by deformable soil is presented. The finite element modelling and analysis is carried out using ANSYS software under normal loads as well as under seismic loads. Various load combinations are considered as per IS-1893 (Part-1):2002. The interaction analysis is carried out with and without shear wall to investigate the effect of inclusion of shear wall on the total and differential settlements in the footings due to deformations in the soil mass. The frame and soil mass both are considered to behave in linear elastic manner. It is observed that the soil-structure interaction effect causes significant total and differential settlements in the footings. Maximum total settlement in footings occurs under vertical loads and inner footings settle more than outer footings creating a saucer shaped settlement profile of the footings. Each combination of seismic loads causes maximum differential settlement in one or more footings. Presence of shear wall decreases pulling/pushing effect of seismic forces on footings resulting in more stability to the structures.

An experimental investigation on contact compression lap splice in circular columns

Due to the rapid development in design of multistory buildings and, because of the variation in stories height with the fixed length of the steel reinforcing bars, steel is usually wasted particularly in columns. Hence, compression lap splice may be used within the column height in order to avoid such waste in steel reinforcement which necessitates the optimization of this splice length.In the ACI 318-11 Provisions, the calculated compression lap splice in members with high strength concrete can be longer than tension splice. Hence, an optimization of compression lap splice would contribute to significant saving particularly in columns. This paper presents an experimental study to investigate the behavior of compression lap splice in circular reinforced concrete columns.The objective of the present investigation is to study the influence of splice length, volume of transverse reinforcement and end bearing condition on the behavior of compression lap splice. The conducted investigation included experimental tests of nine circular columns under uniaxial compression loads. All spliced bars were in contact with each other and with constant concrete cover. Based on the experimental investigation and test results, concluding remarks have been drawn, based on which a design simplified equation for splice length in compression has been developed. A correlation between the experimental and calculated results of the author specimens and other results available in literature, showed a good agreement. Also, the formulas adapted by different codes for predicting the compression lap splice length have been checked with the proposed equation.

Quantification and Assessment of Safety Risk in the Design of Multistory Buildings

Research has shown that construction worker safety and health is influenced by the design of the permanent structure being constructed. Architects and design engineers have the opportunity to positively affect construction worker safety and health through the choices they make in the design process. Lack of designer knowledge about construction processes and limited availability of tools to assist in assessing the safety risk associated with a design are considered as inhibitors to implementation of the design for construction safety (DfCS) concept. This paper presents research conducted to quantify the construction safety risk of each of the design elements present in typical multistory buildings in the United States. The major research efforts were (1) identification of the typical building design elements and associated construction activities; (2) quantification of the unit and cumulative risks of the design elements and construction activities; and (3) development of an online design risk-assessment tool. Absolute safety risks were quantified for 141 design elements and 683 construction activities using the survey-analytical research method. The risk factors developed were incorporated into an online tool titled Safety in Design Risk Evaluator (SliDeRulE). The research contributes to the construction industry body of knowledge by providing quantitative values that link specific design features to construction safety. The website is designed to assist building designers with assessing the level of construction safety risk associated with their designs and is intended for use by designers during the design phase to create buildings that are safer to construct.

Application of Bioclimatic Parameter as Sustainability Approach on Multi-story Building Design in Tropical Area

Abstract The main objective in construction of a physical facility is to provide a place for humans (bio) in order to achieve their goals. Building as built environment with a particular physical form at a particular location is affected by climate. If the building design process ignores the climate considerations, the influence of climate can lead to interference human activities. Bioclimatic design is a concept of sustainable approach that consider of climate and human relations in reviewing the feasibility of a design. At this time, a growing number of designers, especially young architects that interested in using bioclimatic concept as sustainable approach in their design process. However, the application of this concept in the design process has not shown significant results in building operation. This paper elaborates the bioclimatic concept, in order to obtain a good understanding of bioclimatic design that can be used as a reference, especially for novice designers, in the application of sustainability concepts in the design of multi-story buildings in the tropical area. This paper also suggests a design method that utilizes a sustainable approach which is expected to help novice designers in applying the bioclimatic design concept.

Seismic Isolation Design of Multistory Building

Design process and the nonlinear time history analysis for base isolation system is performed in this paper. The results show that the earthquake acceleration and displacement response of isolated structure can be significantly reduced. Application of the isolation system to improve the seismic capacity of the structure,can effectively reduce the response of upper structure of in earthquake.

Mitigation of Progressive Collapse in Multi-Storey Buildings

This paper describes recent developments in performance-based design of multi-storey buildings against progressive collapse, where particular emphasis is given to practical implementation within the structural design process. The benefits of sudden column loss as an event-independent scenario are highlighted, and its computational merits as well as its correlation with actual extreme dynamic events are emphasised. It is proposed that the robustness limit state should be based on avoidance of failure in the upper floors above the damaged column, where it is proposed that the design envelope should be stretched from the conventional strength limit to the ductility limit so as to achieve economic design for robustness. In addressing the dynamic effects of sudden column loss, load factor approaches that have been recently proposed for use with some new usa design codes are shown to have serious shortcomings, potentially leading to unsafe estimation of dynamic amplification. These shortcomings are effectively addressed by the ductility-centred approach recently developed at imperial college london, which offers a practical multi-level assessment framework for progressive collapse under sudden column loss. Key lessons are drawn from the application of the ductility-centred approach to steel-concrete composite multi-storey buildings, where the inadequacy of prescriptive and load factor approaches is clearly demonstrated, and where the benefits of such factors as connection ductility, additional connection reinforcement, axial restraint, infill panels and rate-sensitivity are highlighted.

Development of a wind tunnel model compared with results of method of initial parameters and BS6399 models for dynamic analysis of multi-storey building subjected to aerodynamic loadings

The research investigated the development of a wind tunnel model compared with results of method of initial parameters and BS6399 models for dynamic analysis of a multi-storey building subjected to aerodynamic loadings. The dimensional analysis which based its concept on the law of motion and energy conservation was used as wind tunnel experimental data assessment tool, for the determination of the aerodynamic loadings for a multi-storey building. Although, this problem was earlier solved using dimensional analysis with different approaches by many Scholars but such solutions did not include an important quantity; the influence of the structure’s deflection (δ) and foundation infinitesimal rotation. The study observed that, the non-stationary component is also dependent of the stationary component of the aero-dynamic force. It also explained how the product of the Strouhal number (St) and model relative displacement (Lo number), is equal to the Bernoulli universal constant, 0.5. Tests on most important parameters capable of influencing the assessment and design of multi-storey buildings with varying height-breadth ratio, basic wind speeds, relative displacement and aspect ratio increased with logarithmic laws as a function of model height; but the reduced frequency, decreased with polynomial and power laws respectively. It was therefore concluded that, aero-elastic damping property of the structure is influenced by the Lo number and in particular, λ. Finally, the cumulative base moment from the mathematical (method of initial parameters) model is 2.108% higher than the physical model result and the results from the BS6399 model was less by 1.732%. In general, a difference varying between ±2.1% is within acceptable level of deviation for most conventional engineering and scientific design results. Key words: Dimensional analysis, Strouhal number, Bernoulli universal constant, wind tunnels, initial parameters, BS6399, multi-storey buildings, aero-elastic damping, aero-dynamics loadings.

New visual languages supporting design of multi-storey buildings

This paper deals with designing multi-storey buildings with the use of a knowledge-based visual design support system. In this system two visual languages for creating design solutions by the designer are proposed. The first one allows the designer to design 2D floor layouts, while the second one is dedicated to creating 3D building structures. The generated design solutions in the form of drawings are internally represented as hierarchical hypergraphs gathering design knowledge on which reasoning about designs can be based. The approach is illustrated by example of designing a three-storey house.

Effect of Spans Length on Structural Design of Multi story Buildings

Effect of Spans Length on Structural Design of Multi story Buildings

Elastic and ductile design of multi-storey crosslam massive wooden buildings under seismic actions

The paper discusses the seismic design of multi-storey buildings made from cross-laminated timber panels (‘crosslam’). The use of seismic analysis methods such as the modal response spectrum and the non-linear static (push-over) analysis is discussed at length, including issues such as the modelling of crosslam walls and connections, the evaluation of the connection stiffness, and the schematization of floor panels. It was found that it is crucial to account for the flexibility of the connections (hold-downs and angle brackets) between upper and lower walls, since otherwise the vibration periods of the building would be underestimated. The basics of capacity design to ensure the attainment of ductile mechanisms in crosslam timber structures under seismic actions are presented. The ductile failure mechanism is characterized by plasticization of connectors (hold-downs, angle brackets and screws) between adjacent wall panels and between panels and foundations. The crosslam panels and the connections between adjacent floor panels must be designed for the overstrength of the connectors to ensure that they remain elastic during the earthquake and the ductile failure mechanism is attained. Based on the results of preliminary quasi-static cyclic tests, a value of 1.3 was found for the overstrength factors of hold-downs and angle brackets. A case study multi-storey crosslam massive wooden building was then analysed using the non-linear push-over analysis as implemented in the N2 method recommended by the Eurocode 8. The building was modelled using shell elements and non-linear links to schematize the hold-downs and angle brackets. The building ductility, calculated from the bilinear curve equivalent to the actual non-linear push-over curve, was then investigated. Such a quantity, defined as the ratio of the displacement at the near collapse state and the maximum elastic displacement of the top floor, was found to rise from 1.7 to 2.5 when ductile instead of brittle hold-downs and angle brackets are used. Furthermore, the maximum peak ground acceleration the building can resist raised from 0.2 g to 0.4 g , demonstrating the importance of using ductile connectors in seismic design.

Direct Displacement Based Seismic Design of High Rise Structures with Strengthened Stories (I) - Theory

High rise structures with strengthened stories are widely used nowadays. A rational seismic design procedure for this kind of structure is thus necessary. Based on mode theory and direct displacement based seismic design of multi-story buildings, this paper proposed a new direct displacement based seismic design procedure. In the proposed method, each mode of the high rise structure is equivalent to a single degree of freedom (SDOF) system. Seismic response of each mode is calculated and adds up to consider the contributions of higher modes. Considering the characteristic of strengthened stories, two stories above the strengthened stories are taken as the “key stories”, whose performance indicates the performance of the building. The proposed procedure is logical, simple and can serve for reference of actual design.

Dynamics of Structures—Theory and Applications to Earthquake Engineering, Third Edition

Previous editions of Anil Chopra’s Dynamics of Structures set the standard as textbook of choice for teaching structural dynamics with an eye to earthquake engineering. This third edition has come out nearly eleven years after the first hit the bookshelves, and what a fruitful decade this has been for earthquake engineering (see review of the second edition in Earthquake Spectra 17, 549). Performance-based earthquake engineering, which was in its infancy when the first edition of this book was published, is now entering its second generation. Application of nonlinear dynamics, which was limited to small academic circles and graduate studies, is now center stage for evaluation and design of major structures. Today, hardly any serious evaluation or retrofit of a substantial building is complete without at least considering either static or dynamic nonlinear analyses. The revisions included in the third edition of Dynamics of Structures reflect the changing characteristics of structural dynamics as applied in practice; as such, this book can be useful in teaching future engineers what they need to know to hit the ground running when they graduate. As previous editions did, the book can also serve as a comprehensive reference on the subject for practicing engineers who need to understand old as well as cutting-edge topics of structural dynamics. The major revisions to the book are reflected in Part III, the section that covers earthquake response and design of multistory buildings. In particular, Chapter 19, which deals with earthquake analysis and response of inelastic buildings, has been completely rewritten. In the second edition, this chapter contained only 23 pages; in this edition it has been expanded to 60 pages. Furthermore, the chapter has been divided into two separate parts. The first part covers what has been traditionally referred to as nonlinear time-history analysis, which is recently and more accurately referred to as nonlinear response-history analysis. The second part deals with approximate methods of nonlinear analysis consisting of various pushover analysis techniques, including modal pushover analysis, for which the author has been one of the leading pioneers. Based on structural dynamics theory, the modal pushover analysis procedure is developed and its accuracy evaluated. Chapter 21, which deals with various building code interpretations of structural dynamics principles, has also been significantly revised and enhanced, and now includes explanation and discussion of the relevant provisions of the 2006 International Building Code, 2005 National Building Code of Canada, 2004 Mexico Federal District Code, and 2004 Eurocode 8. New in the third edition, Chapter 22 discusses methods for estimating seismic demands promulgated in performance-based guidelines for evaluat-

A parametric natural fire model for the structural fire design of multi-storey buildings

A parametric natural fire model is presented, which is derived on the basis of simulations with heat balance models for realistic natural design fires, taking into account the boundary conditions of typical compartments in residential and office buildings. These so-called iBMB parametric fire curves are formulated with the help of simplified empirical equations which can easily be used for structural fire design as part of a performance-based natural fire design concept. The iBMB parametric fire curves are checked and validated by comparison with results of different heat balance models and with published fire tests from different fire research laboratories. In addition, a natural fire test in a test room with ordinary office room furnishings has been performed which supports the parametric natural fire model presented here. The application of the iBMB parametric fire curves is demonstrated by means of an example.

Application of the equivalent static force procedure for the seismic design of multistorey buildings with vertical mass irregularity

The seismic forces and deformations obtained from the equivalent static force procedure and the dynamic analysis method proposed for the 2005 National Building Code of Canada are compared for 4-, 8-, 12-, and 16-storey buildings with structural mass irregularity. Setbacks resulting in 200% and 300% mass discontinuities located at 25%, 50%, or 75% of the building height were considered. The buildings are located in Vancouver and Montréal, and lateral loads are resisted by concentrically braced steel frames. The storey shear forces, overturning moments, and storey drifts obtained from static analysis were found to exceed the values determined from dynamic analysis for all irregular structures except at the base of "podium-type" buildings located at the Vancouver site.Key words: mass, static, dynamic, seismic, shear, overturning moment, deflections, braced steel frames.

Review of Dynamics of structures: Theory and applications to earthquake engineering by Anil S. Chopra

I am most pleased to be asked to provide a review of the subject textbook. I have used both the first and second editions of this book over the past two years for classes in structural dynamics and in earthquake engineering. In my mind, this textbook is an excellent resource for the pedagogy of the graduate classroom, as well as a powerful aide to practicing structural engineers for their use in understanding the dynamics of structures and their response to ground motion. The book is organized into three parts: Part I deals with the fundamentals of undamped and damped single degree of freedom ~SDOF! systems; Part II, undamped and damped multidegree of freedom ~MDOF! systems; and Part III, earthquake response and design of multistory buildings. Each academic year I teach most of the material for a two-course graduate sequence from Chopra’s book. The first course is an introductory class in structural dynamics, and the second is a more advanced class in earthquake engineering. In my first class in structural dynamics, over the course of a 15-week semester, I use material from five of the eight chapters in Part I ~which cover SDOF equations of motion, free vibration with and without damping, response to harmonic and arbitrary loadings and ground motions, and response spectra methods!. I also use material from five of the nine chapters in Part II ~which cover MDOF equations of motion, free vibration with and without damping, and the very important topic of modal methods for linear systems!. In my second semester class in earthquake engineering, I use one chapter from Part I dealing with earthquake response of linear systems, two chapters from Part II of the book, which deal with earthquake analysis of linear systems and tuned-mass damping, and three of the four chapters in Part III of the book, which address topics in multistory buildings, elastic and inelastic response, and structural dynamics in building codes. The book provides numerous examples which illustrate the theory, and which are very useful as explanatory material for the classroom. Some of the exercises in the back of each chapter