일본은 지진이 상당히 많은 나라로 그중에서도 목조건물이 1300년간 계속해서
 바람.지진 등에 견디면서도 지금까지 남아있는 것은 인간의 위대한 힘의 결과라고
 안다. 이와 같이 과학과 기술은 상당한 차이의 내용을 갖고 있다. 이것이 18C에
 들어서면서 근대과학과 기술과의 관계가 생기게 되었다.

구조물의 내진설계 ( Earthquake-Resistant Design of Structures )

Open Ground Storey (OGS) framed buildings in which the ground storey is kept open without providing any infill walls and mainly used for parking, are increasingly common in urban areas. Vulnerability of this type of buildings has been exposed in the past earthquakes.
OGS buildings are conventionally designed considering a bare frame analysis, ignoring the stiffness of the infill walls present in the upper storeys, which under-estimates the inter-storey drift and the force demand in the ground storey columns. To compensate this, a multiplication
factor (MF) is introduced by various international codes while calculating the design forces (bending moments and shear forces) in the ground storey columns. Present study focuses on the evaluation of seismic performances of OGS buildings designed with alternative MFs through performance-based design approach using a probabilistic
framework. The probabilistic seismic demand models and corresponding fragility curves for all the selected OGS buildings are developed for different performance levels. Reliability curves are developed for the OGS building frames against the seismic hazard associated with
maximum seismic zone of India (Zone-V of IS 1893, 2002). Similar analyses are also carried out on bare frames and fully infilled frames for reference. It is found from the present study that the application of MF only in ground storey, as suggested by many literatures and design codes (including Indian standards), is not an appropriate solution for design of OGS buildings as it leads to vulnerable adjacent storey. This study proposes an effective scheme of MF for design of OGS buildings that yields acceptable levels of reliability index.

Reliability Based Seismic Design of Open Ground Storey Framed Buildings

From the last few decades the construction of tall stacks increases due to increase in air pollution. Here in this paper, the “Self supporting steel chimney” of height 60m was considered and analysed for the prevailing wind forces and seismic forces considering chimney in four different earthquake zones and bending moments, shear forces were calculated using IS 6533 (part1&2):1989 and were also plotted. Also the chimney was modelled using STAAD PRO Vi8 software. And in the next part, is to justify the code criteria with regard to basic dimensions of industrial steel chimney. A total of 66 numbers self supporting steel flared unlined chimneys with different top-to-base diameter ratio and height-to-base diameter ratio were considered for this study. The thickness of the chimney was kept constant for all the cases. Maximum bending moments and stresses for all the chimneys were calculated for wind load using MSExcel sheets and were plotted as a function of top-to-base diameter ratio and height-to-base diameter ratio.

https://www.ijraset.com/fileserve.php?FID=6673

Analysis of Self Supported Steel Chimney

Seismic pounding between closely spaced building structures is one among the main causes of severe building damages observed in seismically proven regions. Due to the earthquake-induced vibrations, the buildings which are adjacent to each other with dissimilar dynamic characteristics will move out of phase resulting in the collision as there would be no energy dissipation system to accommodate the relative motions. Seismic pounding can be prevented by passive structural control of energy dissipation systems, i.e., dampers. The current study aims to mitigate the seismic pounding observed in the adjacent buildings connected with fluid viscous dampers (FVDs). G+14 and G+9 multistoried adjacent buildings are modeled and analyzed using ETABS 2017. Two stories are connected with one viscous damper. Adjacent buildings with similar height (G+14 storied) and varying height (G+14 & G+9 storied) connected with FVDs subjected to El Centro earthquake are studied. Nonlinear time history analysis is carried out. Considering displacement and seismic gap as the main parameters, adjacent buildings with similar and different height connected with and without FVDs are compared.

Mitigation of Seismic Pounding Observed in Adjacent Buildings with Fluid Viscous Damper

Due to urbanization and industrialization, which paved the door for the development of tall, multi-story structures on mountainous terrain, land is scarce in emerging nations like India. Buildings built on hilly terrain differ from those built on flat terrain due of their uneven and asymmetrical vertical and horizontal structures. These buildings are also significantly more vulnerable to earthquake pressures when located in mountainous terrain. The primary goal of the current endeavor is to investigate how structures behave on level and sloping terrain. Hilly places require different construction configurations than level areas. Hill structures vary from those on lowlands in that they are torsionally linked, highly irregular, and asymmetrical in both the horizontal and vertical planes. As a result, they are vulnerable to severe damage when an earthquake strikes. The behavior of a multi-story structure with two distinct slope angles was attempted to be studied in this paper, and a comparison with flat ground was made. by taking Earthquake Zone II into account. Buildings on level ground and buildings on slanted ground are compared. The models are created with the aid of the structural analysis program ETABS. Response spectrum analysis is used for analysis. The analysis’s findings, including storey shear, storey drifts, moments, and displacement, are tabulated and examined.

Seismic analysis of Multi storey Building on Sloping Ground and Flat Ground by using ETABS

Each structure is to be designed for strength, limiting deflection, and durability. The function and aesthetics of structures should keep in consideration during achieving this strength, deformation and durability. It may possible when the structural engineer had quite knowledge about architectural requirements. In case of high-rise structure, certain failures may occur due to lateral loads. The lateral loads are almost wind and earthquake, whose main horizontal force component acting on the different members of structure. The lateral force effects due to wind and earthquake loads are usually analyzed as an equivalent static load in most type of high-rise structure. These structures are designed in such a way that its every component must resist two types of loads like vertical Load due to gravity and lateral load due to earthquake and wind. The reinforced concrete chimney shell, which transfer vertical load and lateral load to the foundation. The present study is on the analysis of cantilever reinforced concrete chimney with variation in geometry and different orientation, when they are subjected to the lateral loads. 
This report shows the certain design values for different configurations of chimney structures which may take consideration for foundation designing work. The effects of lateral force due to wind and earthquake loads are analyzed by an equivalent static load method and dynamic analysis by response spectrum method. The present study is carried for the region Nashik, district of Maharashtra state in India. According to which wind load and earthquake load parameters were considered as per IS code such as IS 4998(part-1):1992, IS 1893 (part-4):2005 and IS 875(part-3). The present study is carried only to study the merits and demerits of these types of chimney configuration based on the analysis, for such terrain conditions.

/pdf/analysis-of-self-supporting-steel-chimney-4hcfgv8ur0.pdf

Analysis of self supporting steel chimney

In this paper enlightening the problem Parking space for residential apartments in populated cities is a matter of major concern. Hence the trend has been to utilize the ground storey of the building itself for parking. “Open Ground Storey” (OGS) buildings are those types of buildings in which the ground storey is free of any infill masonry walls. These types of buildings are very common in India for parking provisions. The strength and stiffness of infill walls in infilled frame buildings are ignored in the structural modeling in conventional design practice.

/pdf/analysis-of-major-international-codal-design-provisions-for-kb7050h8pu.pdf

Analysis of major international codal design provisions for open ground storey buildings

Major seismic events during the past decade such as those that have occurred in Northridge, Imperial Valley (May 18, 1940), California (1994), Kobe, Japan (1995), Turkey (1999), Taiwan (1999) and Bhuj, Central Western India (2001) have continued to demonstrate the destructive power of earthquakes, with destruction of engineered buildings, bridges, industrial and port facilities as well as giving rise to great economic losses. Among the possible structural damages, seismic induced pounding has been commonly observed in several earthquakes. As a result, a parametric study on buildings pounding response as well as proper seismic hazard mitigation practice for adjacent buildings is carried out. Therefore, the needs to improve seismic performance of the built environment through the development of performance-oriented procedures have been developed. To estimate the seismic demands, linearity of the structure is to be considered during devastating earthquakes. Despite the increase in the accuracy and efficiency of the computational tools related to dynamic analysis, engineers tend to adopt simplified solution oriented procedures instead of doing rigorous analysis when evaluating seismic demands. This is due to the problems related to its complexities and suitability for practical design applications. This project entitled “Study of Seismic Pounding Effects Between Adjacent Buildings” aims at studying seismic gap between adjacent buildings by linear dynamic analysis in ETABS .A parametric study is conducted to investigate the minimum seismic pounding gap between two adjacent structures by response Spectrum analysis for hard soil and Earthquake recorded excitation are used for input in the dynamic analysis on different models. Pounding produces acceleration and shear at various story levels that are greater than those obtained from the no pounding case, while the peak drift depends on the input excitation characteristics. Also, increasing gap width is likely to be effective when the separation is sufficiently wide practically to eliminate contact.

https://ijariie.com/AdminUploadPdf/“STUDY_OF_SEISMIC_POUNDING_EFFECTS_BETWEEN_______________________________________________ADJACENT_STRUCTURES”_ijariie5933.pdf

Study of seismic pounding effects between adjacent structures

The buildings situated on hill slopes in earthquake prone areas are generally irregular, torsionally coupled and hence, susceptible to serve damage when affected by earthquake ground motion. Such buildings have mass and stiffness varying along the vertical and horizontal planes, result the center of mass and center of rigidity do not coincide on various floors. The dynamic analysis is carried out using response spectrum method. The dynamic response that is fundamental time period, storey displacement and base shear action induced in columns has been studied for buildings of different heights. These results show that the performance of step back and set back building frames are more suitable in comparison with step back building frames. But after considering bracings to the step back building frames, a better performance can be observed when compared with step back and set back building frames. Three dimensional space frame analysis is carried out for four different configurations of buildings ranging from eight, ten and twelve storey resting on sloping ground. Building models are analyzed by ETABS software to study the effect of time period, storey displacement and base shear.

https://ijariie.com/AdminUploadPdf/“ANALYSIS_OF_SEISMIC_BEHAVIOUR_OF_MULTI_STORIED_R_C_C__BUILDINGS_RESTING_ON_SLOPING_GROUND_AND__BRACING_SYSTEM”_ijariie6008.pdf

“analysis of seismic behaviour of multi-storied r.c.c. buildings resting on sloping ground and bracing system”

The present study attempts to estimate typical variations in magnification factor of a mid rise open ground storey building accounting for the variability of compressive strength and modulus of elasticity of infill walls with various infill arrangements so that it can help designers facing trouble with heavy designs for a structure of mid-size, with the given material properties, geometry and loadings in particular. For the present study Equivalent static analysis (ESA) and Response spectrum analysis (RSA) is considered for the comparative study. The building will be analyzed for two different cases: i) Considering infill mass but without considering infill stiffness. ii) Considering both infill mass and infill stiffness. From the present results it is found that building with soft storey will exhibit poor performance during a strong shaking. But the open ground storey is an important functional requirement of almost all the urban multi-storey buildings and hence cannot be eliminated. Alternative measures need to be adopted for this specific situation. The under-lying principle of any solution to this problem is in i) increasing the stiffness of the ground storey; ii) provide adequate lateral strength in the ground storey. The possible schemes to avoid the vulnerability of open ground storey buildings under earthquake forces can be by providing stiff columns in open ground storey buildings or by providing adjacent infill walls at each corner of soft ground storey buildings.

http://www.ijariie.com/AdminUploadPdf/Analysis_of_Multi_Story_Buildings_Infill_and_Without_Infill_Walls_by_Simulation_Tool_ijariie7383.pdf

dr.ajay swarup

Papers

Analysis of self supporting steel chimney

Analysis of major international codal design provisions for open ground storey buildings

Study of seismic pounding effects between adjacent structures

“analysis of seismic behaviour of multi-storied r.c.c. buildings resting on sloping ground and bracing system”

Analysis of Multi-Story Buildings Infill and Without Infill Walls by Simulation Tool