Review on Seismic Analysis of Multistoried Building in Hilly Region

Due to sloping land and high seismically active zones, designing and construction of multistory buildings in hilly regions is always a challenge for structural engineers. This review paper focuses to establish a review study on the Possible Types of building frame configuration in the hilly region and he behavior of Such building frames under seismic loading conditions, and (3) The recent research and developments to make such frames less vulnerable to earthquakes. This paper concludes that the dynamics characteristics of such buildings are significantly different in both horizontal and vertical directions, resulting in the center of mass and center of stiffness having eccentricity at point of action and not vertically aligned for different floors. When such frames are subjected to lateral loads, due to eccentricity it generates torsion in the frame. Most of the studies agree that the buildings resting on slanting ground have higher displacement and base shear compared to buildings resting on plain ground and the shorter column attracts more forces and undergoes damage when subjected to earthquake. Keywords: Building frame configuration, Seismic behavior, Dynamic characteristics, Response spectrum analysis, time history analysis.

Parametric modeling compressed ellipsoid of rotation as the analytic surface

The article deals with the shaping of the analytical surface in the form of a compressed ellipsoid of rotation. In the process of research, the principle of the golden section was applied, an ellipsoid of rotation with optimal parameters for the design of a large-span unique building of the exhibition complex was obtained. To solve the problem of choosing a rational analytical surface in the Lira-CAD software package, three variants of constructive solutions for the frame of the exhibition complex have been developed. The finite element method is used, the most popular numerical calculation method for studying the stress-strain state of large-span buildings and structures. The analysis of the calculation results made it possible to choose the optimal variant of the structural solutions of the building frame. The check of the dynamic characteristics of the proposed structural solution of the building frame is carried out. The obtained results of the dynamic calculation showed the correctness and efficiency of the adopted structural solutions of the building frame.

Digital models of parametric structures

Formation of parametric structure digital model are considered. Investigation was based on the analysis of the shaping evolution of the analytical surface in the form of a hyperboloid of rotation. Finite element frame represents a spatial plate-rod system has been developed during creation of the digital model. This scheme allows to study the effectiveness of constructive solutions under dynamic influence at the design stage. Dynamic characteristics of various design solutions are considered in process of choosing a rational variant of the building frame. The influence of the inclusion of outrigger floor in the model of the frame at various levels of the building are investigated. The proposed method of research and application of the possibilities of the shaping evolution allows to proceed to the modernization of BIM technologies in the design of unique buildings. Recommendations for refining the algorithm for studying parametric object digital models were developed.

Comparative Study of Seismic Analysis of Vertically Irregular R.C. Frame using INDIAN and EURO Code

This research article carried out on comparison of codes (Indian and Euro) for seismic behaviour of R.C building frame. The main cause for the earthquake occurred in the R.C. building, if there is any irregularity in the structure and, if the structure is not constructed with proper strength, and not appropriately designed, which causes the structures to completely collapse. It is critical to understand seismic analysis and construct earthquake resistance structures for the safety of a multi-story building against seismic forces. It has been observed that the Gulf countries’ construction requirements are primarily based on EURO standards. So that we analyse an R.C building frame of G+22 with vertical geometry irregularity using comparison with EURO standards and INDIAN standards. The response of the building is being calculated by the Response Spectrum approach with the help of ETABS software. The calculated results of an irregular building are then characterized graphically and in tabular form. This research paper concentrated on the variations in outcomes found by using these codes i.e., Indian & Euro code. This comparative result is performed in the form of Storey Drifts, Overturning moment, Storey shear, and Storey Displacement in the X, and Y direction.

Dynamic response of the building construction system with a finite degree of freedom under a special action

Introduction. In the normative documents of a number of countries on the standardization of the protection of buildings and structures from progressive collapse, for the calculation analysis under special impact, such a concept as a “zone of possible local destruction” of a structural system is used, outlined by a fragment of the building frame in places of hypothetically removed structural elements. The purpose of identifying such most stressed zones in the form of substructures is engineering visibility of the consequences of an emergency impact with an assessment of the stress-strain state of elements falling into such a zone. In this regard, in the work under consideration, a variant of modeling the dynamic additional loading of the reinforced concrete frame of a multi-storey building caused by its structural restructuring is proposed, which makes it possible to determine the parameters of the dynamic response of the substructure in the form of a two-span continuous beam with a finite number of degrees of freedom and to model in more detail the zone of possible local destruction of the elements of the building frame at the sudden removal of one of the structural structures in this area. Materials and methods. The zone of possible local destruction of the building frame is modeled by a fragment of the structural system adjacent to this zone. The process of removing a column was simulated by applying a load P(t) in the opposite direction, equal to the force in the removed column, calculated when calculating the entire frame of the building. To solve the system of equations of motion of the substructure, we use the method of expansion in terms of natural vibration modes, which is well known in the dynamics of structures. Results. The results of theoretical studies of the dynamic effect of a reinforced concrete structural system of a building with a finite number of degrees of freedom during its sudden restructuring caused by a special emergency impact in the form of a hypothetical removal of one of the load-bearing structures are presented. Conclusions. The equations of motion of a substructure in the form of a two-span continuous beam with a finite number of degrees of freedom constructed on the basis of the theory of the dynamics of structures can be used to analyze the special limiting state of reinforced concrete elements of structural systems of frames of buildings and structures.

Analysis of Retrofitted Cold Formed Steel Multistory Building Frame

The cold formed steel section are increasingly used as a structural elements in low rise buildings in recent times, due to the advantages like economic production, easy transportation, low labor cost and high strength to weight ratio. In the current work a G+3 storied building frame is studied for seismic and wind load using Staad-pro software. Light gauge section is taken for beam and slab elements. The seismic analysis is carried out by Equivalent static method. After analysis the results such as story displacement, story drift, Base shear and time period are compared for different models. The building frame is also analyzed for wind load. In the current work cross bracing using Light gauge element used as a retrofitting technique. The retrofitted building frame is analyzed for wind and seismic loads and results obtained for time period, storey displacement, storey drift and base shear values are compared with the corresponding values of base frame. The results of retrofitted frame showed shortening in time period, storey displacement and story drift values in X&Z directions indicating the increased ductility, Stiffness and strength of structure. Hence the proposed retrofitting technique could be believed to achieve success results in increased strength and ductility values required by wind and seismic loading.

Construction Sequence Analysis and Conventional Lumped Analysis considering P-Delta Effect by Using Etabs

While analyzing a multistorey building frame, conventionally all the probable loads are applied after modeling the entire building frame. But in practice the frame is constructed in various stages. Accordingly, the stability of frame varies at every construction stage. Even during construction freshly placed concrete floor is supported by previously cast floor by formwork. Thus, the loads assumed in conventional analysis will vary in transient situation. Obviously, results obtained by the traditional analysis will be unsuitable. Therefore, the frame should be analyzed at every construction stage taking into account variation in loads. The phenomenon known as Construction Sequence Analysis considers these uncertainties precisely. Therefore, the building structure should be analysed at every stage of construction taking into account the load variations. In this project two cases have been considered. Whereas in Case 1 the multistoried building (G+22 storied) with floating columns and transfer girder will be analysed by response spectrum method and considering P-delta effect as a whole for the subjected loading and in Case 2 the multistoried building (G+22storied) with floating columns and transfer girder will be analysed by response spectrum method with reference to the construction sequence or staged construction and considering P-delta effect. In the present study a G+22 storey multistoried R.C.C building model is modelled using Etabs 2019 software. Response spectrum analysis is made by considering building situated in zone III.Building models are analyzed by Etabs 2019 software to study the effect of maximum positive moment, maximum negative moment, maximum shear forces, maximum deflection, maximum torsion moment of transfer girder beam and total axial load under transfer girder and floating column etc

STABILITY OF THE METAL FRAME ELEMENTS WHEN WORKING IN CRAMPED CONDITIONS

The static operation of the building frame elements formed from thin-walled open profiles located in a monolithic foam concrete array is considered. This arrangement increases the overall stability and fire resistance of the floor beams.

IMPROVING THE STABILITY OF METAL FRAME ELEMENTS WHEN WORKING TOGETHER WITH FOAM CONCRETE

The static operation of building frame elements is considered. A comparison of the load-bearing capacity of floor beams made of rolled steel and beams made of thin-walled curved pro files is given