• Wind and Structures
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• v.30 no.4
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• pp.423-432
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• 2020

A steel high-rise building (HRB) with 15 stories was analyzed under the dynamic load of wind or four different earthquakes taking into consideration the effect of soil-structure interaction (SSI) and using tuned mass damper (TMD) devices to resist these types of dynamic loads. The behavior of the steel HRB as a lightweight structure subjected to dynamic loads is critical especially for wind load with effect maximum at the top of the building and reduced until the base of the building, while on the contrary for seismic load with effect maximum at the base and reduced until the top of the building. The TMDs as a successful passive resistance method against the effect of wind or earthquakes is used to mitigate their effects on the steel high-rise building. Lateral displacements, top accelerations and straining actions were computed to judge the effectiveness of the TMDs on the response of the steel HRB subjected to wind or earthquakes.

• Structural Engineering and Mechanics
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• v.30 no.6
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• pp.651-664
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• 2008

The purpose of this study is to develop a rehabilitation technique for heavily earthquake damaged masonry buildings. A full scale one storey masonry building with window and door openings was manufactured and tested on the shock table by applying increased amplitude free vibration up to the point where heavy earthquake damage was observed. Damaged test building was rehabilitated with vertical and diagonal steel straps and then tested again. The effectiveness of improvements obtained by the rehabilitation technique was investigated. Steel straps improved the lateral strength and stiffness of masonry walls and limited the lateral displacement of building. Stability of the masonry walls were also improved by the steel straps. Steel straps reduced the natural period of the earthquake damaged masonry building and prevented the failure of the building at the same amplitude of free vibration.

• Steel and Composite Structures
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• v.22 no.3
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• pp.647-662
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• 2016

This study aims to monitor the variation of modal frequencies of steel buildings during their construction sequence. In this respect, construction of a steel building is followed by vibration based measurements. The monitored building is a three-story educational building within a building group whose structural system consists of steel moment resisting steel frames and eccentric braces. Five different acceleration measurements in two perpendicular directions are taken on five different construction stages, starting from the erection of the columns and beams ending with the completion of the construction. The recorded measurements are transferred into frequency domain and the dominant frequencies for each case have been determined. The change in the dominant frequencies is evaluated with the existing construction stages and performed constructional works between the stages. The last measurement, performed on the building in service, revealed the first two dominant frequencies as mutual in X and Y direction, showing that these dynamic modes are torsional modes. This result is investigated by numerical analysis performed with finite element model of the building constructed for design purpose. Lower frequencies and different mode shapes are determined from numerical analysis. The reason of lower frequencies is discussed and the vibration survey is extended to determine the effects of an adjacent building. The results showed that the building is in strong relation with an adjoining building in spite of a designed construction joint.

• Earthquakes and Structures
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• v.12 no.3
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• pp.263-270
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• 2017

In this study, two geometrically identical multi-storey steel buildings with different lateral load resisting systems are structurally analyzed under same earthquake conditions and they are compared with respect to their construction costs of their structural systems. One of the systems is a steel structure with eccentrically steel braced frames. The other one is a RC wall-steel frame system, that is a steel framed structure in combination with a reinforced concrete core and shear walls of minimum thickness that the national code allows. As earthquake resisting systems, steel braced frames and reinforced concrete shear walls, for both cases are located on identical places in either building. Floors of both buildings will be of reinforced concrete slabs of same thickness resting on composite beams. The façades are assumed to be covered identically with light-weight aluminum cladding with insulation. Purpose of use for both buildings is an office building of eight stories. When two systems are structurally analyzed by FEM (finite element method) and dimensionally compared, the dual one comes up with almost 34% less cost of construction with respect to their structural systems. This in turn means that, by using a dual system in earthquake zones such as Turkey, for multi-storey steel buildings with RC floors, more economical solutions can be achieved. In addition, slender steel columns and beams will add to that and consequently more space in rooms is achieved.

• Steel and Composite Structures
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• v.16 no.3
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• pp.289-303
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• 2014

In recent, development of construction and design technology gives taller, larger and heavier steel framed structures. With the tendency of increasing high-rise building, this study is strongly related to structural system, one of significant components in structural design. This study presents an innovative structural system, with high performance steel material, diagrid. Its detail, structural analysis, and structural experiments are all included for the development of new structures.

• Computers and Concrete
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• v.27 no.4
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• pp.343-353
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• 2021

In this study, in order to improve the seismic performance of existing reinforced concrete (RC) framed structures, various external attachment of corner steel frame configurations was considered as a user-friendly retrofitting method. The external steel frame is designed to contribute to the lateral stiffness and load carrying capacity of the existing RC structure. A six-story building was taken into account. Four different external corner steel frame configurations were suggested in order to strengthen the building. The 3D models of the building with suggested retrofitting steel frames were developed within ABAQUS environment using solid finite elements and analyzed under horizontal loadings nonlinearly. Horizontal top displacement vs loading curves were obtained to determine the overall performance of the building. Contributions of steel and RC frames to the carried loads were computed individually. Load/capacity ratios for the ground floor columns were presented. In the study, 3D rendered images of the building with the suggested retrofits are created to better visualize the real effect of the retrofit on the final appearance of the façade of the building. The analysis results have shown that the proposed external steel frame retrofit configurations increased the lateral load carrying capacity and lateral stiffness and can be used to improve the seismic performance of RC framed buildings.

• International journal of steel structures
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• v.18 no.4
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• pp.1431-1439
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• 2018

For floating buildings may fl oat on the water for a long time, they are constantly affected by various environmental loads such as wind and wave loads. In this study to find the wave effect on the floating building, five models are designed using steel moment resisting frame. It is assumed that the lower part of the floating building is a reinforced concrete pontoon, while the upper part is a three-story steel frame. To analyze floating buildings affected by wind and wave loads, hydro-dynamic and substructure analysis are performed. As input loads, this study set limits that the mean wind velocity is 35 m/s and the significant wave height is 0.5 m for the residential building. From the hydrodynamic analysis, the time-history acceleration of building is obtained and transformed into a base ground input for a substructure analysis of the superstructure of the building. Finally the mean of the maximum from 30 dynamic analysis of the floating buildings are used to be compared with the results of the same model on the ground. It was shown that the dynamic results with wind and wave loads are not always lesser than the static results which are calculated with static equivalent wind load for a building that is located on the ground.

• Steel and Composite Structures
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• v.20 no.2
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• pp.399-412
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• 2016

This paper evaluates the seismic response of three dimensional steel space buildings using the spread plastic hinge approach. A numerical study was carried out in which a sample steel space building was selected for pushover analysis and incremental nonlinear dynamic time history analysis. For the nonlinear analysis, three earthquake acceleration records were selected to ensure compatibility with the design spectrum defined in the Turkish Earthquake Code. The interstorey drift, capacity curve, maximum responses and dynamic pushover curves of the building were obtained. The analysis results were compared and good correlation was obtained between the idealized dynamic analyses envelopes with and static pushover curves for the selected building. As a result to more accurately account response of steel buildings, dynamic pushover envelopes can be obtained and compared with static pushover curve of the building.

• Steel and Composite Structures
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• v.5 no.5
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• pp.395-405
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• 2005

This work introduces to the international scientific community the Chinese Code on fire safety design of steel building structures. The aim of the Code is to prevent the structure of a steel building subjected to fire from collapsing, ensure safe evacuation of building occupants, and reduce the cost for repairing the damages of the structure caused by fire. The main contents of the Code is presented in this paper, including the fire duration requirements of structural components, fundamental requirements on fire safety design of steel components, temperature increasing of atmosphere and components in fire, loading effect and capacity of various components in fire, and procedure for fire-resistant design of steel components. The analytical approach is employed in the Code and the effectiveness of the Code is validated through experiments.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2001.11a
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• pp.148-156
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• 2001

The korean Standard of the length of steel bar is 6m and 8m for building structures. This paper is to investigate the length of steel bar to reduce the loss of steel bar comparing with the steel length(6m, 8m) using today. This research shows that using of the others length of steel bar(7m, 9m) is able to reduce the loss up to 2.27%.