Seismic Analysis of 3D Framed Building

Generally RC framed structures are designed without regards to structural action of masonry infill walls present. Masonry infill walls are widely used as partitions. These buildings are generally designed as framed structures without regard to structural action of masonry infill walls. They are considered as non- structural elements. RC frame building with open first storey is known as soft storey, which performs poorly during strong earthquake shaking. Past earthquakes are evident that collapses due to soft storeys are most often in RC buildings. In the soft storey, columns are severely stressed and unable to provide adequate shear resistance during the earthquake. Hence a combination of two structural system components i.e. Rigid frames and RC shear walls or Rigid frames and Bracings leads to a highly efficient system in which shear wall and bracings resist the majority of the lateral loads and the frame supports majority of the gravity loads.

Design Calculation for A (G +10) Building (Encode Steel)

The proposed steel building at Mumbai consisting of G+10 storeys, has a built-up area of about 165m2. The typical floor height is 3m above GL and the total height of the building above GL is 33m.Withreference to given plan, the architectural drawings and structural drawings showing plan, elevation, sectional views and connection drawings are drawn by using AUTOCAD 2017.Design calculations (Dead Load, Live Load, Wind Load, Seismic Load) are calculated manually-As per IS codes which are mentioned in technical details. The rolled steel sections for beam and column has been chosen from IS 12778:2004. High tensile steel grade-E350BR has been used for steel sections. And, the analysis of structure is done by using STAAD.Pro V8i SS5.Design of beam and column are manually calculated-As per IS: 800-2007. And, spread sheet has been created to check the beam and column, whether it is safe or not. The connection designs are calculated-As per IS codes by using Welding-As per IS 9595-1996 and Fasteners-As per IS 3757-1985. Bracings are provided in the ground floor between the column to avoid soft storey failure. The material requirements are mentioned based on the design calculations. The total estimation of the building is 1.11cr.

A survey of damage observed in Izmir due to 2020 Samos-Izmir earthquake

An earthquake of magnitude 6.9 hit the city of Izmir (Turkey) on 30 October 2020, resulting in 117 deaths (in Turkey) and considerable economic losses. The earthquake also triggered a tsunami. Following the earthquake, field surveys are being conducted in a Covid-secure way to study and document the damages caused. The earthquake caused significant damages to residential buildings mainly located in the district of Bayrakli and Bornova. However, no damages were observed in railway and roadway bridges or tunnels and that helped the rescue operations. The damages were mainly structural which included the so-called pancake collapse (where the entire building collapsed) and soft storey type collapse (weak storey characterised with weak columns collapsed), and in some cases, only the ground floor completely collapsed. Due to the proximity of the epicentre and the geology of the area, it seemed that the ground motions were amplified. This technical note provides a summary of the seismological and recorded ground characteristics of the earthquake together with the lessons learnt.

Seismic Retrofitting of a Structure with Soft Storey and Floating Column.

Tremors are called one in everything about preeminent erratic and annihilating of every cataclysmic event, be that as it may, the flighty idea of the incidence of those seismic tremors makes it inconvenient to hinder loss of living souls and annihilation of properties, if the constructions don’t seem to be designed to oppose such seismic tremor powers. During this paper, a shot has been made to review set up irregularities specifically torsional irregularity and re-entrant corners within the frame structure. These inconsistencies square measure made according to IS 1893:2016 (part1) code. Irregular model and regular model were considered which were analyzed exploitation ETABS 2018 to see the unstable reaction of the structure. The models were analyzed exploitation static and dynamic ways, parameters thought-about being displacement, storey drift, torsional irregularity.

Comparative analysis of vertical irregularities on high rise structure considering various parameters

Now, every day tall constructing structures constructed around the goal of residential and industrial cause etc. Layout of tall buildings both earthquake as well as wind loads got to be take into considered. An irregular structure, failure of structure starts at a point of its weakness and those weaknesses comesups withs separation of mass, stiffness and geometry of that models. The structures having this kinds of discontinuity are called Irregular structures. (H, J, & darshan, 2017) [2]. For example,Structures with the soft storey were the foremost remarkable fallen structures. Therefore, the impact of vertical alignment within the seismic structure of buildings is very significant. The changes in durability and size provide powerful features of those structures that are completely different from the standard structure. For this present evaluation ‘ETABS’ software package is employed. All Reinforced Concrete structural elements are follows as per ‘IS 456:2000 (Plane and Reinforce Concrete-Code of Practice, Bureau of Indian Standard)’. Seismic load follows with respect to IS 1893:2016 along with self-weight of modelles for analysis of the structure. Here 2 kinds of buildings of (G+15) were created one is regular structure and alternative one Mass irregular. To observe, Effect of lateral in both buildings using Seismic load and to check the results,most of maximum displacement for various models and various parameters.

Comparative Study of RC Multistorey Building with Floating Column and Shear Wall Subjected To Seismic Load

: In modern multistorey building construction, irregularities like the soft storey, vertical and plan irregularities, floating columns etc are very common. Building with an open ground storey for parking is a common feature that results in floating columns. Floating columns provide column free space and a good aesthetic architectural view of the building. floating column means the end of any vertical element that rests on the beam which leads to discontinuity of columns such that the path of load distribution in multi-storey buildings is disturbed. The use of a floating column also tends to increase the moment in the column, storey shear etc which highly undesirable in seismically active areas. So, the study of the best location where the floating column needs to be provided to reduce the impact due to seismic loads is of primordial importance. Shear wall is a vertical member which is provided from foundation to top storey. In this study shear wall is used in the direction of orientation so that it provides additional strength and stiffness to the buildings. In the present analysis, 8 models are studied. The first model considers a multi-storeyed building without any shear wall and floating column. Other models analysed are with shear wall and by varying the location of floating columns. The analysis and design are done by STAAD.pro V8i SS6 version software and the method used is response spectrum analysis in earthquake zone 4. The effect of floating column location on parameters such as Base shear, Displacement, Maximum moment, storey shear and percentage of steel reinforcement are discussed. The comparison of results of different models is also carried out in detail using graphs and bar charts in this study. The suitable location for providing a floating column with the shear wall is also discussed. Keywords: Floating column, Shear wall, Seismic load, STAAD.pro.v8i, Response Spectrum Analysis.

Behavioural Study of Infill’s Walls on Soft Story Building

Open ground storey or soft storey is a typical feature in multistory structures in urban areas. This open storey is provided to accommodate parking, reception lobbies, office, communication hall etc. Many of structure having soft storey suffered major damage and collapsed in recent earthquakes. During an earthquake, because of variation in stiffness in soft story and its adjacent floors the inter story drift can occur and the lateral forces cannot be well distributed along the height of building. Lateral forces concentrate on soft story causes large displacement. In this work, an attempt has been made to observe the behavior of gradual decrease in stiffness of building, by using different types of infill material. This work discusses Optimum Earthquake response of tall buildings by response spectrum method as per IS 1893:2002 (Part- I) in ETAB’S software. Seismic parameters like storey stiffness and storey displacement are checked out.

Evaluation of the period and soft story conditions of reinforced concrete buildings with and without infill walls

Since the ground floor of most of the buildings in our country is designed as a shop or ground floor (in the buildings created as a workplace), there is very little infill wall ratio on the ground floors due to architectural and functional reasons, and some of them do not even exist at all. However, infill walls significantly increase the horizontal rigidity and strength of the structure, thus causing a decrease in the period value that determines the earthquake loads that will affect the structure. However, the infill wall meets the first destructive forces of the earthquake, and during this time, it cracks and absorbs some of the earthquake energy. The structural system elements of the building (columns and shear walls) start to meet the earthquake forces only when the infill walls are damaged and fail. In this direction, the aim of this study is to investigate to what extent the amount of infill wall on the ground floor affects the period of the building, and whether there are soft storey irregularities in the building according to the change in the amount of infill wall on the ground floor. In this study, while there are infill walls on all floors and all axes of buildings of various heights (3, 6, 9 and 11 floors), the amount of infill walls in the x and y directions on the ground floors is reduced to a certain extent, and many models are created until the ground floor is completely without infill walls. All these models created were analyzed with the support of the SAP2000 program, and the period values were determined and examined according to the soft storey problems and compared with the case of the entire building with and without infill walls. In addition, it was examined whether the period formulas determined as a result of the studies and taking into account the infill wall give realistic results for the situation examined in this study.