scholarly journals Implementing Different Tubular Framings on High-Rise Structures and Optimizing their Cost and Drift Control with an Optimum Column Spacing

2020 ◽  
Vol 16 (2) ◽  
pp. 320-328
Author(s):  
Saadat Malik ◽  
Syed Ikram Ul Haq ◽  
Safdar Abbas Zaidi ◽  
Ataullah Maher

AbstractThis paper presents the results of variation in column spacing of a tube in its outer periphery concerning structural drift and cost optimization. For high rise structures, tubular framing and outrigger braced frames are considered as the most appropriate solution economically. In recent past not must study has been focused on the tubular frame in its columns spacing and span length. In this research, a simple square plan structure has been considered with different heights of 30, 40, and 50 story buildings. Six different framing systems of the tubular structure have been developed with different column spacing in each and employed to each high-rise structure. Concrete strength and steel yield strength has been taken as a fixed value for every model. Several models were developed with these combinations and the drift and structural safety have been optimized by reducing the cross-section sizes in each system. Seismic analysis has been carried out to evaluate the effects of varying column spacing in each tube. The comparison of all the employed systems was carried out and cost analysis has been made. Observations have been taken from drift, base shear, and cost analysis of each framing system of the tube, and certain results were concluded for structures with different height.

Seismic analysis of structural systems with floor diaphragms has been a requisite in the recent past. The duty of a structural engineer is to be prudent about the behavior of every structural system adopted. Amongst the structural systems that are adopted world over, diaphragm with rigid and semi-rigid floor plate are adopted widely in the analysis. This research focuses on the backstay effect i.e. podium structural interaction with the tower area and consideration of retaining wall as increment of lateral stiffness as specified in latest tall building code IS6700:2016 for low and high rise structures. In the current study models were prepared with low to high rise storeys with rigid and flexible diaphragms considering backstay diaphragm placing tower at center and corner. The models were subjected to seismic forces; response spectrum along with the combination of the gravity loads. The structural responses like natural periods, base shear, displacement and inter storey drift were also studied.


2019 ◽  
Vol 2 (1) ◽  
pp. 153-164
Author(s):  
Umesh Jung Thapa ◽  
Ramesh Karki

In this paper, study of the response (base shear, time period, storey drift, storey displacement) of a structure is done for the tall building including basement with fixed base and with pile foundation considering Soil Structure Interaction (SSI). Finite element based program ETABS2016 v16.1.0 is used for the analysis of the superstructure. Seismic analysis is done to get the dynamic response of superstructure for two types of model,one model is with fixed baseand second is Model with Winkler spring for Chhaya Center, Thamel, a high rise building with 14 story including double basements. Itisobserved with the consideration of Soil Structure Interaction (SSI). The soil is replaced by spring and assigned at joints. El Centro earthquake (1940) is used for time history analysis. The response obtained due to SSI effect is compared with fixed based model. Results of analysis presented include the comparison of natural periods, base shears, displacements and overturning moment. It is observed that the natural periods increase and the base shears decrease as the base become more flexible.


Author(s):  
Mr. Suryakant Pandey

Abstract: In this day and age of urbanization, there is a strong need for a large-scale high-rise apartment building in every city but high-rise construction systems are extremely difficult to construct in any seismic region due to the intense and disruptive nature of seismic forces. Seismic forces have the highest risk of causing the most harm to high-rise buildings. To meet this need, the Civil Engineering industry is constantly developing new groundbreaking techniques. To solve this problem RCC or steel bracings are provided in high-rise buildings which help to the low down the effect of seismic and wind forces. The main objective of this paper is to locate an effective position and pattern of the RCC X-bracing system in the L- shape multi-storey building which is subjected to seismic forces. According to a previous reference paper, X-bracing produces better results than other bracing systems. Analysis the seven types of frame models are taken – (1) Normal L-shape building without bracing, (2) Xbracing are provided at the face of L-shape building, (3) X-bracing are provided alternative pattern at the face of L-shape building from bottom to top floor, (4) X- bracing are provided zig-zag pattern at the face of L-shape building, (5) X-bracing are provided at the corner of L-shape building, (6) X-bracing are provided alternative pattern at the corner of L-shape building from bottom to the top floor, (7) X-bracing are provided zig-zag pattern at the corner of L-shape building. Developed and evaluated by response spectrum analysis method (Linear dynamic analysis) as per IS 1893-2000 using STAAD PRO V8i. In the present work G+12 storey, the L-shape frame structure is analyzed by using X-bracing. It is analyzed and the results of the Following Parameters are taken - (1) Peak storey shear, (2) Base shear, (3) Nodal displacement, (4) Maximum bending moment, (5) Total quantity of steel in the whole structure, (6) Total volume of concrete in the whole structure are evaluated and compared. Keywords: RCC Bracing, Seismic Behavior, Seismic Analysis, Peak Storey Shear, Base shear, Nodal Displacements, Maximum Bending Moment, The Total Quantity of Steel, The Total Volume of Concrete


2010 ◽  
Vol 163-167 ◽  
pp. 3918-3924
Author(s):  
Jun Teng ◽  
Hu Bing Tu ◽  
Huan Lin Mao ◽  
Ying Liang Qiu

As an important seismic analysis method, Pushover is widely used in high-rise buildings, while there is still lack of investigation on applicability of Pushover analysis on diagonal grid structural system. Two structures with height 144 and 288 meters are respectively built, and then Pushover analysis and Incremental dynamic analysis are conducted. Results calculated by two different methods are compared, including top displacement vs. base shear curve, inter-story drift vs. inter-story shear curve, distribution of inter-story drift angle along the building height and plastic developing sequence of structural weak positions. Meanwhile, influence of three lateral load patterns (uniform pattern,inverted triangle pattern and SRSS pattern) on the results is investigated. Analysis results demonstrate that Pushover analysis can in some extent reflect seismic performance of structures and SRSS load pattern can better capture global and local information of structures compared with other two patterns.


Due to gradual development of metros and small towns and increasing population in India, the high rise buildings are constructed at a larger scale due to land scarcity and the commercial or cultural importance of a particular area. A high rise building should be architecturally viable and should have good light and air ventilation. In this project we compare and analyze the high rise buildings in three configurations.A high rise building is a structure which is more than 30m in height. In this project we consider a high rise building with story configuration of G+20. The three configurations of the high rise building are designed, configured and seismically analysed using ETABS software. Earthquake analysis in ETABS is carried out on Model (a)-Structure without a shear wall, Model (b)-Structure with shear walls and Model (c)-Structure with openings in shear walls resting in Type II soil and Type III seismic zone. The soil type and seismic zone considered for this project is specific for Amaravati the capital of Andhra Pradesh. Seismic analysis results for each configuration of the high rise building such as Base Shear, Time Period, Storey Drifts and Displacements are compiled and compared to find the suitable configuration of high rise structure.


In the present Era escalation of multi-storey high rise building is very common because of rapid urbanization in the entire world also innovation in the field of Engineering, science and Technology. Also Engineers have sophisticated designing software. As height of the building increases building response to the wind and seismic load increases. It means that forces and displacement of the structure is directly proportional to the height of the structure. Many research studiesare going on to reduce the structural instability due to high speed winds and earthquakes. During the earthquake the multi-storey high rise structures are failed to resist the seismic loads and it become the catastrophic disaster for human life’s and for the country. It is most important that structure should be able to withstand against external excitation forces. This can be achieved by building structure more flexible.During the time of earthquake multistorey structures are swing and large deformation is occurred and vibrations are transferred in the structure through the ground which causes instability in structure. Thus the use of damper is resists lateral forces (wind load, earthquake load) and providing stability to the structure. Dampers are the mechanical devices which dissipate energy which is facilitate in multi-storey structure to reduce the displacement, buckling of beams and columns and increases the structural stiffness. There is lot of various types of dampers are used in RC multi-storey building. This study deals with performance and selection of suitable type of damper which will be more resistant to earthquake for the selected multi-storey building and different seismic parameters like time period, story stiffness, story displacement, story drift and base shear are checked out. In this study seismic behavior of multi-story RCC building with various types of dampers like fluid viscous damper, friction damper and tuned mass damper is carried out.


Author(s):  
Ankur Verma

Abstract: Today, larger part of designs around us are built up concrete cement (RCC) outlined constructions. To forestall harm because of quake there is a need to foster powerful procedure to expand the strength and flexibility of elevated structures. Shear wall are steadier and more pliable and thus can bear more even loads. In this paper, we have proposed a relative report between block facade, shear divider and uncovered casing by using ETABS programming. This review is essentially centered around seismic conduct of G+12 building. The outcomes are talked about as far as base shear, sidelong relocation, story float, story solidness and normal period for every one of the three models. We find that shear wall has least parallel uprooting and least time span when contrasted and block facade and uncovered edge. Likewise, we track down that the shear divider model is more adaptable because of lesser float when contrasted and different models. The upsides of removal and float for shear wall is likewise not as much as block facade since the tallness of the structure increments. Keywords: shear wall, bare frame, Response spectrum, Earthquake, ETABS


CONSTRUCTION ◽  
2021 ◽  
Vol 1 (2) ◽  
pp. 93-101
Author(s):  
Saffuan Wan Ahmad ◽  
Muhammad Aimran Amzar Kamarudin ◽  
Wan Aniq Ridhwan Wan Ariffin

On the 5th June 2015, an earthquake hit Ranau, Sabah with a magnitude of 6.0 that caused 18 casualties and several injuries are one of the examples that show Malaysia is not safe from any seismic event. Most of the structure in Malaysia was designed not to include seismic action.  Furthermore, an area that has a high density of population such as in the central region (Klang valley) and several main cities in Malaysia has less available land to build landed housing and uses high-rise apartments as an alternative. High-rise buildings that are normally having problems with soft story mechanisms and plan irregularity which could lead to severe damage when earthquakes happen. This study aims to observe the response of high-rise buildings when under different earthquakes in the presence of shear walls. To achieve this objective two models were modelled and analyzed by using ETABS software, the one with a shear wall and the one with no shear wall. The methods used in this study were the response spectrum method and time-history analysis. In the end, the parameters observed were base shear, story stiffness, story drift, and story displacement. The observations highlighted that the effect of earthquake intensities shows a significant effect. The acquired results indicated that the building with the shear wall is more resistant and strong structures as compared to buildings without shear wall when undergoing seismic analysis.


Mathematics ◽  
2021 ◽  
Vol 9 (15) ◽  
pp. 1758
Author(s):  
Koji Tsuchimoto ◽  
Yasutaka Narazaki ◽  
Billie F. Spencer

After a major seismic event, structural safety inspections by qualified experts are required prior to reoccupying a building and resuming operation. Such manual inspections are generally performed by teams of two or more experts and are time consuming, labor intensive, subjective in nature, and potentially put the lives of the inspectors in danger. The authors reported previously on the system for a rapid post-earthquake safety assessment of buildings using sparse acceleration data. The proposed framework was demonstrated using simulation of a five-story steel building modeled with three-dimensional nonlinear analysis subjected to historical earthquakes. The results confirmed the potential of the proposed approach for rapid safety evaluation of buildings after seismic events. However, experimental validation on large-scale structures is required prior to field implementation. Moreover, an extension to the assessment of high-rise buildings, such as those commonly used for residences and offices in modern cities, is needed. To this end, a 1/3-scale 18-story experimental steel building tested on the shaking table at E-Defense in Japan is considered. The importance of online model updating of the linear building model used to calculate the Damage Sensitive Features (DSFs) during the operation is also discussed. Experimental results confirm the efficacy of the proposed approach for rapid post-earthquake safety evaluation for high-rise buildings. Finally, a cost-benefit analysis with respect to the number of sensors used is presented.


2012 ◽  
Vol 39 (8) ◽  
pp. 867-877 ◽  
Author(s):  
Damien Gilles ◽  
Ghyslaine McClure

Structural engineers routinely use rational dynamic analysis methods for the seismic analysis of buildings. In linear analysis based on modal superposition or response spectrum approaches, the overall response of a structure (for instance, base shear or inter-storey drift) is obtained by combining the responses in several vibration modes. These modal responses depend on the input load, but also on the dynamic characteristics of the building, such as its natural periods, mode shapes, and damping. At the design stage, engineers can only predict the natural periods using eigenvalue analysis of structural models or empirical equations provided in building codes. However, once a building is constructed, it is possible to measure more precisely its dynamic properties using a variety of in situ dynamic tests. In this paper, we use ambient motions recorded in 27 reinforced concrete shear wall (RCSW) buildings in Montréal to examine how various empirical models to predict the natural periods of RCSW buildings compare to the periods measured in actual buildings under ambient loading conditions. We show that a model in which the fundamental period of RCSW buildings varies linearly with building height would be a significant improvement over the period equation proposed in the 2010 National Building Code of Canada. Models to predict the natural periods of the first two torsion modes and second sway modes are also presented, along with their uncertainty.


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