Seismic Response of R.C. Structures with Different Steel Bracing Systems Considering Soil - Structure Interaction
Enhancing the seismic performance of R.C. structures through steel bracing and soil-structure interaction
by K. S. Patil*, Ajit K. Kakade,
- Published in Journal of Advances and Scholarly Researches in Allied Education, E-ISSN: 2230-7540
Volume 15, Issue No. 2, Apr 2018, Pages 411 - 413 (3)
Published by: Ignited Minds Journals
ABSTRACT
In this study the seismic response of reinforced concrete structure using steel bracing considering soil structure interaction to increase the horizontal stability of structure and rigidity of the structure. In which it is assumed that the building is fixed at it bases, but in reality the soil medium allows movement to some extent due to its property to deform. Therefore, this may decrease the stiffness of the structure and hence may increase the natural periods of the system. Thus, the process in which soil influences the movement of the structure and further this movement of structure influence the response of the soil is termed as Soil-Structure Interaction. Using different bracing X, V, Chevron bracings in different positions and with effect of SSI and without of SSI to strengthening the R.C. structure.
KEYWORD
seismic response, R.C. structures, steel bracing systems, soil-structure interaction, horizontal stability, rigidity, building, soil medium, deform, stiffness
1. INTRODUCTION
The purpose of the structure is to transfer vertical loads safely. vertical loads include dead load, live load, beside these loads building is also affected due to lateral loads formed because wind and seismic forces. Lateral load produces high stresses, results in movement and vibration of the structure. Therefore necessitate improving the stiffness along the lateral direction to resist the horizontal forces. Steel bracings are most economical method for resting the lateral forces and increasing the rigidity of the structure. Steel bracing has used to stabilise world‘s tallest buildings against the lateral loads and stiffness. Bracing is effective because it provides rigidity and strength against lateral shear. The seismic force transfer compressive and tensile forces in the bracings. a choice of bracing used along the height of frame. X, V bracing reduce the bending movement of frame. Earthquake is natural method in which there is movement. These produces surface waves produce surface vibration on which the structure stands. Therefore study is considered on soil structure soil.
2. LITERATURE REVIEW
A) Mohamed M. Ahmed (2015) [1]: Author has consider moment resisting frame carried out three different methods of seismic analysis i.e response spectrum analysis, and nonlinear time method with nine different time history inputs recorded during earthquake.
B) Dhanaraj M. Patil (2015)[2] : This study find out the seismic behavior of different bracings of steel frame used: MRFs, braced frame (CBFs), (VBFs),(XBFs) C) S. A. Halkude, S. M. Barelikar et al. (2014)[3]:
The author has studied the seismic response for R.C.C frame. Soil is modeled using elastic continuum approach dynamic analysis is carried out using response spectrum given in IS 1893 – 2002 in SAP 2000 software. Three buildings having 2 storeys, 5 storeys, and 8 storeys are considered
D) S.H. Kalyani et al (2014) [4] :
The author has considered the seismic response for R.C. frames with isolated footing Soil is modeled
E) Dr.Abhay Sharma et.al. (2014)[5]: In this study, seismic analysis for high rise RC building frames considering different types of bracing systems.In proposed problem G+10 story building frame is analysed for varying bracing system under seismic loading.
F) Dhiraj raj, Bharathi M.(2013)[6]
“Among all position and orientation of bracings, the buildings with inverted mid bracing has the least storey drift in Zones IV and V‖ G) H.R.Naseri et al. (2011)[7] : This author investigates the different steel braced structures placed on various types of soil with varying hardness.
3. METHODOLOGY
a) Selecting type of frame structure with different type of bracings and plan of building and height of building as shown in fig 1
Fig 1
b) Isolated type of footing is considered with different soil strata. c) Different position of bracings and structure including and excluding soil structure interaction are considered. As shown in fig 2
Fig 2
d) Properties of soil are taken through the IS 1893:2002.
4. CONCLUSION
1) According to this study, the position of braces to the middle of the frame reduces the drift much more than adding them to the ends 2) The stiffness characteristics depending on the dynamic soil properties and the dimensions of foundation. 3) Roof displacement increasing due to incorporation of SSI. For soft soil roof displacement is higher than fixed support condition. It increases up to 29%. 4) The performance quantities like displacements, acceleration and base shear are affected due to soil structure interaction. 5) Among all position of bracings the building with X bracing has minimum roof displacement. Therefore X bracing gives better performance during earthquake
5. REFERENCES
Dhanaraj M. Patil, Keshav K. Sangle (2015) ―Seismic Behaviour of Different Bracing Systems in High Rise 2-D Steel Building‖The institution of Structural Engineers,Elsevier.
Dhiraj raj, Bharathi M. (2013) “A four storied reinforced concrete (RC) building (without bracing and with bracing at different locations and orientation)International SymposiumNovember pp.20-21, 2014 Geohazards: Science, Engineering and Management
K. S. Patil1* Ajit K. Kakade2
nonlinear analysis has been conducted to evaluate the effect of distributing the bracings in different spans with different number of storeys and influence of different cross sections of the braces.IOSR Journal of Mechanical and Civil Engineering (IOSR-JMCE) e-ISSN: 2278-1684,p-ISSN: 2320-334X, Volume 11, Issue 3 Ver. III (May- Jun. 2014), PP 12-19 Dr. S. A. Halkude (2014) ―Soil Structure Interaction Effect on Seismic Response of R.C. Frames with Isolated Footing”International Journal of Engineering Research & Technology (IJERT),ISSN: 2278-0181,Vol. 3 Issue 1, January – 2014.
H. R. Naseri et. al. (2011) “This paper investigates the nonlinear behavior of various steel braced structures placed on different types of soil with varying hardness.
Mohamed M. Ahmed, Tarek M. A. Alazrak (2015) ―Evaluation of soil-foundation-structure interaction effects on seismic response demands of multi-story MRF buildings on raft foundations‖ International Journal of Advanced Structural Engineering (IJASE) ISSN 2008-3556 Volume 7 .
Rishi Mishra, Dr. Abhay Sharma ―Analysis of RC Building Frames for Seismic Forces Using Different Types of Bracing Systems‖, International Research Journal of Engineering and Technology (IRJET), ISSN: 2278-0181, Vol. 3 Issue 7, July – 2014
S. H. Kalyani et. al. (2014) ―seismic response of R.C. frames with isolated footing.Soil is modeled using elastic continuum approach.
Corresponding Author K. S. Patil*
Assistant Professor, Civil Engineering Department, JSPM‘s, ICOER, Wagholi, Pune
E-Mail – kuldeepseti@gmail.com
