STABILITY ANALYSIS OF STEEL FRAME STRUCTURES: P-DELTA ANALYSIS (original) (raw)
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Stability of a six storey steel frame structure
2011
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IJERT-A Study On Bracing Systems On High Rise Steel Structures
International Journal of Engineering Research and Technology (IJERT), 2013
https://www.ijert.org/a-study-on-bracing-systems-on-high-rise-steel-structures https://www.ijert.org/research/a-study-on-bracing-systems-on-high-rise-steel-structures-IJERTV2IS70765.pdf The major concern in the design of multi-storeyed steel building is to have good lateral load resisting system along with gravity load system because it also governs the design. This paper is presented to show the effect of different types of bracing systems in multi storied steel buildings. For this purpose the G+15 stories steel building models is used with same configuration and different bracing systems such as Single-Diagonal, X bracing, Double X bracing, K bracing, V bracing is used. A commercial software package STAAD.Pro V8i is used for the analysis of steel buildings and different parameters are compared. The property of the section is used as per IS 800:2007 which incorporates Limit State Design philosophy.
Study of P-Delta Effect on Tall Steel Structure
The high rise buildings require high frame structure stability for safety and design purposes. This research focused on Pdelta effect on the Tall Steel Structures and compared with linear static analysis. In this study, a 40 storey steel frame structure with m has been modelled by using SAP2000 structural analysis software with the consideration of P-delta effect. At the same time the influence of different bracing patterns has been investigated. For this reason five types of bracing systems including X, V, Single Diagonal, Inverted V , with unbraced model of same configuration are modelled and analysed. The framed structure is analysed for Earthquake load . After analysis, results showed that displacement due to P-Delta effect is 40% more compared to linear analysis and increase in the Axial force is about 8% for bare frame. The X bracing proved to be more stiff and effective with respect to linear analysis and P-Delta analysis. The decrease in the displacement is about 47.5% and 47.9% for linear and second order analysis.
Study on Dynamic Analysis of Steel Structure with Different Types of Bracings
The structure in high seismic areas may be susceptible to the severe damage. Now a days steel bracings in steel structure are most popular system to resist lateral load due to earthquake. Braced frame resist seismic excitation with comparatively less deformations than gravity load resisting system as they form a stiff system. Steel bracing is economical, easy to erect, occupies less space and has flexibility for meeting the required strength and stiffness. In the present work it is exposed, effect of seismic loading in 15 storey regular bare building using ETABS software. This buildings adapted different types of bracings such as diagonal, braced diagonal, X, K, K with bracing, chevron, braced chevron, V, eccentric diagonal and Knee bracings. The seismic response are evaluated by using equivalent static analysis, response spectrum analysis and linear time history analysis for bhuj earthquake data on Zone-V. Finally analysis results are carried out such as maximum storey displacement, inter storey drift, storey shear and natural time period. Based on the results regular braced buildings are compared and studied best braced structure to resist lateral loads. In three methods of analysis results in regular braced models, X bracings and chevron bracings system showed better resistance to seismic forces than the other specified bracing systems. The bracings provide adequate stiffness and continuous load path.
Comparative Study of Different Bracing Systems for Irregular High Rise Steel Structure
The civil Engineering industry particularly in India has taken a new mode in construction of high rise structures. High rise structures became a need and new trend to accommodate the people’s requirements. As steel structures can be fabricated and erected in no-time compared to R.C.C structures, modern technologies and construction industries are focusing towards the construction of high rise structures using steel. In designing the high rise structures, the effect of lateral loads like wind and earthquake forces are attaining increasing importance and stability against lateral loads because of high height of buildings. For this reason in0recent years wind and earthquake loads have become0determining factors in designing tall structures To attain the resistance against these lateral loads, bracing system is used with different patterns. Bracing system are such structural system which0form an integral part0of frame. The structure has to0be analysed before0arriving the best type0or effective arrangement0of bracing. A 20 storied, irregular 3D framed structure with 3m each story depth is selected for the present study. The columns and beams are designed0to withstand dead load and live load0adequately. The bracings are designed to withstand against lateral load coming in that particular stories. For better results, the various forms of bracing systems are analysed using STAAD Pro software. An attempt has been made to study the behaviour of high rise steel structures for lateral loads by considering Knee and Y bracing systems and also for other bracing systems like X brace, V brace and combination of X and Y braces. Various models thus generated were analysed for different zones, different wind speeds and compared with unbraced0reference model with respect0to criteria’s like base shear, axial force, bending moment, shear force, drift index,0inter story drift and also to have maximum0reduction in inter storey0drift and drift index0per unit quantity0of steel consumed for0bracing configuration which0improves the lateral load0resisting capacity of the tall structures.
A Study On Bracing Systems On High Rise Steel Structures
2013
The major concern in the design of multi-storeyed steel building is to have good lateral load resisting system along with gravity load system because it also governs the design. This paper is presented to show the effect of different types of bracing systems in multi storied steel buildings. For this purpose the G+15 stories steel building models is used with same configuration and different bracing systems such as Single-Diagonal, X bracing, Double X bracing, K bracing, V bracing is used. A commercial software package STAAD.Pro V8i is used for the analysis of steel buildings and different parameters are compared. The property of the section is used as per IS 800:2007 which incorporates Limit State Design philosophy.
Analysis of Various Steel Bracing Systems using Steel Sections for High Rise Structures.pdf
Steel structures can be strengthened in various types, to resist the lateral forces coming on the structure. In steel buildings, the most widely used method of constructing lateral load resisting system is using braced frames. These systems help the structure to reduce the buckling of columns and beams and the stiffness of the structure is increased. Hence, the main concern while analyzing steel structure is to select the appropriate bracing model and to decide the suitable connection type. The steel bracings are also used in retrofitting to give maximum strength to the structure. In this study, the behavior of the bracing system is analyze for parameters like displacement, weight etc by using different types of bracing systems e.g. X bracing, V bracing, Inverted V bracings, Knee bracings. These bracings are analyzed and designed by using STAAD Pro V8i software. For this analysis the G+9 storey building with different bracing system has been analyzed and designed as per Indian Standard Code 800-2007 by using UC and UB (British) sections for the wind, earthquake and gravity loads also their combinations.
Analysis of Various Steel Bracing Systems using Steel Sections for High Rise Structures
2016
Steel structures can be strengthened in various types, to resist the lateral forces coming on the structure. In steel buildings, the most widely used method of constructing lateral load resisting system is using braced frames. These systems help the structure to reduce the buckling of columns and beams and the stiffness of the structure is increased. Hence, the main concern while analyzing steel structure is to select the appropriate bracing model and to decide the suitable connection type. The steel bracings are also used in retrofitting to give maximum strength to the structure. In this study, the behavior of the bracing system is analyze for parameters like displacement, weight etc by using different types of bracing systems e.g. X bracing, V bracing, Inverted V bracings, Knee bracings. These bracings are analyzed and designed by using STAAD Pro V8i software. For this analysis the G+9 storey building with different bracing system has been analyzed and designed as per Indian Stand...
ANALYSIS OF STEEL FRAMES WITH BRACINGS FOR SEISMIC LOADS
IAEME, 2019
In recent decants steel structure had played an important role in construction industry. Providing strength, stability, ductility for buildings designed for seismic loads. It is necessary to design a structure that can withstand under seismic loads. Providing steel knee braces is one of the structural systems used to resist earthquake forces on structures. Steel bracing is economical, easy to erect and occupies less space which is flexible to design to meet the required strength and stiffness. There are various types of steel bracing (X, knee bracing). In knee brace frame system (KBFS) the non-buckling diagonal bracing provide most of the lateral stiffness, the flexural yielding of knee element. In our project a 6 storey steel frame building with knee bracing system with floor plan of 9 m x 9m is considered. We studied the performance of a 6 storied steel frame building with knee bracing system and compared with bare frame. Pushover analysis, equivalent static analysis, Response Spectrum analysis, Time history analysis is performed in ETABS based on IS 1893:2002 (part 1) guidelines. The manual calculation was done on the basis of Equivalent static analysis and Response spectrum analysis to find out base shear for foundation and lateral force for each storey deck slab and compared the values with bare frame. Depending on the complexity in the problem for bracing models, we had used Etabs software in order to analysis the Base shear and lateral shear. The results were plotted in the form of graphs and tables for their inter storey drift and inter storey displacement.
Natural disasters question the intelligence of humans. Cyclones and earthquakes are the most devastating disasters. Recently Hudhud cyclone and moderate earthquakes in Indian sub-continent have shown that there is no safe zone on this earth which is free from natural disasters. An attempt was made to improve the lateral strength of the building by incorporating both shear walls and bracings in the same structure. A total of ten models were selected and analyzed for both wind and seismic loads. The static and dynamic analysis was carried out for seismic loads. Both X and inverted V-bracings were used in the selected steel framed building. The response of these models for different loading conditions was observed. Results showed that performance of model 3 was good based on displacements and bending moments, whereas model 2 showed better performance based on axial and shear forces in case of both X and inverted V-bracings.