SEISMIC PERFORMANCE OF HIGH-RISE BUILDING USING …
Transcript of SEISMIC PERFORMANCE OF HIGH-RISE BUILDING USING …
www.tjprc.org SCOPUS Indexed Journal [email protected]
SEISMIC PERFORMANCE OF HIGH-RISE BUILDING USING OUTRIGGER AND
DIAGRID STRUCTURAL SYSTEM
MUSTAFA HUSSAINI1 & SANDEEP NASIER2
1Structural Engineering, Department of Civil Engineering, Chandigarh University, Punjab, India
2Assistant Professor, Department of Civil Engineering, Chandigarh University, Punjab, India
ABSTRACT
From ancient times humans were interested in building structures high, and this was grown by revaluation of
technology in 19th century. After revaluation of technology peoples tried to move from urban lives towards cities for
seeking jobs and life opportunities, in this way cities were over populated and the need for high-rise building was
growing day by day because of lack of available land. But as height of structures increases lateral loads govern the
design of structure. To tackle lateral loads in high-rise buildings there are number of lateral load resisting system
without adding to the tonnage of the building or increase its plan dimension. Outrigger is one of the lateral load
resisting structural systems that can be used. Outrigger system build by a core shear wall and belt truss and outrigger
trusses in order to build the structure laterally stiff and increase its strength. Diagrid is another lateral load resisting
that is newly developed mechanism. Diagrid system attracted the interest from both architects and designers because of
its ability to resist lateral load and gravity load at the same time. Diagrid system gives a good aesthetic view to the
building because of its unique geometry. In this paper a 24 storey building is considered using outrigger and diagrid
system, and it is analyzed by response spectrum analysis, that is a linear dynamic analysis by the use of ETABS
software. The objective of this paper is to do response spectrum analysis and compare performance of 6 different
models with same height but different structure geometry. To find out the effect of different outrigger and diagrid on
seismic performance of the structure.
KEYWORDS: Outrigger, Diagrid, Lateral load resisting system, High-rise building & Response spectrum analysis
Received: May 25, 2020; Accepted: Jun 27, 2020; Published: Aug 07, 2020; Paper Id.: IJMPERDJUN2020686
1. INTRODUCTION
Construction of high-rise building is a big asset for human life as well as wild life, as it can be observed that
deforestation is going on around the world and destroying the habitats of wild life and more importantly the main
source of oxygen on earth (forests). But as the height of structures increases design of the structure will be a big
challenge for engineers because of lateral loads that act drastically on the building, to tackle this challenges there
are number of structural system to resist lateral loads without adding to plan dimension or tonnage of the building.
Outrigger is one of these systems that is commonly used as lateral load resisting system in high-rise and super
high-rise buildings. Another system that is newly developed mechanism for resisting lateral load is diagrid
system. These two systems were modeled and analyzed by ETABS software to compare their performance.
2. LATERAL LOAD RESISTING SYSTEMS
Before structure members were considered to carry only gravity loads, but after advancement in structural system
lateral loads (wind and earthquake) was also taken into account especially in high-rise buildings, as slenderness
and flexibility increases the building will be affected mostly by lateral loads. There no of lateral load resisting
Orig
ina
l Article
International Journal of Mechanical and Production
Engineering Research and Development (IJMPERD)
ISSN (P): 2249–6890; ISSN (E): 2249–8001
Vol. 10, Issue 3, Jun 2020, 7257-7266
© TJPR Pvt. Ltd.
7258 Mustafa Hussaini & Sandeep Nasier
Impact Factor (JCC): 8.8746 SCOPUS Indexed Journal NAAS Rating: 3.11
system that are highly effective against lateral load and a stable building can be designed with. It is important to
find an adequate system depending on height of the structure. Following are some of lateral load resisting
systems:
Rigid frame system
Braced frame system
Shear wall system
Disgrid system
Outrigger system
Tube system
Bundled tube system
3. OUTRIGGER SYSTEM
In order to effectively control the excessive lateral deflection due to lateral loads outrigger system can be used as
lateral load resisting structural system. This system can be used in high seismic zone and wind load dominant.
This system comprises a centrally located core shear wall, belt truss and outriggers that connects the core shear
wall with outer columns so that structure can act as a unit against lateral loads. The configuration of bracing
system can be different in outriggers. The further rotation of outriggers can be resist by outer columns (columns at
the periphery) of the structure. The induced tension and compression forces on these columns can create moment
resisting to the horizontal loading. Analysis of will complicated with braced frame and outriggers because
outriggers will be forced to deflect with braced frame that will be subjected to bending and racking shear
deformation. The same assumption that neglect shear deformation in concrete “plane section remain plane” does
not stand for braced frame. Concrete walls will be assumed as simple wide column and its behavior will be
applied on it but this will not work for trusses.
Figure 1: Behavior of Frames with Outrigger
Seismic Performance of High-Rise Building using Outrigger and Diagrid Structural System 7259
www.tjprc.org SCOPUS Indexed Journal [email protected]
3. DIAGRID SYSTEM
Diagrid is a specific form of space truss. The diagonal are provide at the perimeter of the structure made up of
series of triangulated truss system. There are number of famous structures that are built by diagrid structural
system around the world; Swiss Re in London, Hearst Tower in New York, Capital Gate Tower in Abu Dhabi etc.
(a) (b) (c)
Figure 2: a) Swiss Tower in London b) Hearst Tower in New York c) Capital Gate Tower in Abu Dhabi
Diagrid system has a good aesthetic view and easily recognized. It provide a clear view to the outside the
building and less obstruction. Diagrid structural system provides significant flexibility with floor plan because it
avoids interior and corner columns. Diagrid structural system saves almost 20% of structural steel weight as
compare conventional rigid frame structure. The diagonal members of diagrid structural system can carry both
gravity as well as lateral loads due to its triangulated configuration. Diagrid system minimize shear deformation as
diagonal members carry lateral shear by axial action.
4. MODELING AND ANALYSIS OF 24 STOREY BUILDING
4.1 Modeling of 24 Storey Building
The 24 storey building has (40x40)m plan dimension. The height of each storey is 3.5m. the angle of inclination is
kept the same through the height for diagrid structure. The inclined columns for diagrid structure is provided at
10m spacing. The design dead load and live loads are shown in the table 1. Seismic parameters are given as below
in table 2. Modeling and analysis of all models are carried out using ETABS software. For linear static and linear
dynamic analysis the beams and columns are modeled by beam element, and braces are modeled by truss element.
Table 1: Loading Parameter
S. No Live load in KN/m2 Imposed dead load in KN/m2
1 3 1
Table 2: Seismic parameter
S. No Importance
factor I
Zone Factor
Z
Response Reduction
Factor R
Type of Soil Damping Ratio
1 1 0.24 5 II 5%
7260 Mustafa Hussaini & Sandeep Nasier
Impact Factor (JCC): 8.8746 SCOPUS Indexed Journal NAAS Rating: 3.11
Table 3: Diagrid parameters
S. No Column size in
mm
Beam size in
mm
Bracing size in
mm
Slab thickness in
mm
Angle
Degree
1 700x700 450x450 450x450 200 54
Table 4: Outrigger Parameter
S. No Column size in
mm Beam size in mm
Bracing size in
mm
Core shear wall & slab
thickness in mm
1 700x700 450x450 450x450 200
(a) (b)
Figure 1: (a) Diagrid with an angle of 54o (b) Diagrid in Diagrid with angle of 54o
(a) (b)
Seismic Performance of High-Rise Building using Outrigger and Diagrid Structural System 7261
www.tjprc.org SCOPUS Indexed Journal [email protected]
Figure 2: (a) Diagrid in diagrid (b) Outrigger with X-bracing
(a) (b)
Figure 3: (a) Outrigger with K-bracing (b) Outrigger with E-bracing
4.2 Analysis Results of 24 Storey Building
The analysis result will be shown in terms of time period, base share, dispalcement and overturning moment. The
time period of the models will be shown in table 4 and fig 4. Base share of the building will be shown in table 5
and fig 5. Displacement will be displayed in table 6 and fig 6, and overturning moment will be shown in table 7
and fig 7.
Table 4: Time period
7262 Mustafa Hussaini & Sandeep Nasier
Impact Factor (JCC): 8.8746 SCOPUS Indexed Journal NAAS Rating: 3.11
Figure 4: Time period in sec
Table 5: Base shear in KN
Figure 5: Base shear in KN
Table 6: Displacement in mm
Seismic Performance of High-Rise Building using Outrigger and Diagrid Structural System 7263
www.tjprc.org SCOPUS Indexed Journal [email protected]
Figure 6: Displacement in mm
Table 7: Overturning Moment
7264 Mustafa Hussaini & Sandeep Nasier
Impact Factor (JCC): 8.8746 SCOPUS Indexed Journal NAAS Rating: 3.11
Figure 7: Overturning Moment
5. CONCLUSIONS
In this paper modeling and analysis of 24 storey building with outrigger and diagrid system is presented in details.
A regular floor paln of 40x40 m has been considered for modeling and analysis purpose. All seismic parameters
were drawn from IS 1893:2016 considering all load combinations.
In diagrid system it was observed that all lateral loads are resisted by diagonal memnbers and gravity
loads were resisted by both diagonal members and vertical members as well.
Because of increase in lever arm of diagonal members, this system is very effective in resisting lateral
load.
Outrigger system is also very effective in resisting lateral loads as it can be observed in the results we
obtained but it make disturbance in planning interior and façade of the building. In this paper an attempt has been
made to reduce this disturbance by providing K and E bracing instead of X-bracing, that the result were satisfying
without lose of strenght and stiffness.
But diagrid system provide much more flexibility in terms of planning interior and façade of the
building.
REFRENCES
1. Akshat, & Singh, G. (2018). Dynamic analysis of diagrid structural system in high rise steel buildings. International
Journal of Civil Engineering and Technology, 9(8), 71–79.
2. Chavan, A. V, & Shelar, P. V. V. (2017). Pushover Analysis of High Rise Building and Outrigger System With or
Without In-Filled Walls. International Research Journal of Engineering and Technology(IRJET), 4(7), 1439–1445.
3. Etemad, A. H., & Kumar Tiwary, A. (2019). Article ID: IJCIET_10_03_196 Cite this Article: Abdul Halim Etemad
and Aditya Kumar Tiwary, Comparison of Tubular, Outrigger and Bracing System for Stabilization of High-Rise
Buildings. International Journal of Civil Engineering and Technology (IJCIET), 10(03), 1968–1977.
4. Jani, K., & Patel, P. V. (2013). Analysis and design of diagrid structural system for high rise steel buildings.
Procedia Engineering, 51, 92–100. https://doi.org/10.1016/j.proeng.2013.01.015
5. Kala, A., Mangulkar, M., & Jain, I. (2017). The use of outrigger and belt truss system for high-rise RCC building.
Seismic Performance of High-Rise Building using Outrigger and Diagrid Structural System 7265
www.tjprc.org SCOPUS Indexed Journal [email protected]
International Journal of Civil Engineering and Technology, 8(7), 1125–1129.
6. Kumar, R., & Sharma, P. (2019). Comparative Study of Diagrid Structure System in High Rise Buildings With
Braced Frame Structure. International Journal of Civil Engineering and Technology (IJCIET), 10(3), 1826–1831.
7. Naik, S. R., Desai, S. N., & Naik, M. P. (2018). Article ID: IJCIET_09_13_154 Ratio Considering Seismic Non-
Linear Time History Analysis. International Journal of Civil Engineering and Technology (IJCIET), 9(13), 1532–
1539.
http://www.iaeme.com/IJCIET/index.asp1532http://www.iaeme.com/ijciet/issues.asp?JType=IJCIET&VType=9&IT
ype=13http://www.iaeme.com/IJCIET/issues.asp?JType=IJCIET&VType=9&IType=13http://www.iaeme.com/IJCI
ET/index.asp1533
8. Sapkota, B., Surumi, R. S., & Jeyashree, T. M. (2017). Comparative study on seismic performance of high-rise
building with energy dissipation and outrigger belt truss system. International Journal of Civil Engineering and
Technology, 8(4), 1539–1545.
9. Shadhan, K. K. (2015). Optimal Diagrid Angle To Minimize Drift in High-Rise Steel Buildings. 6(11), 1–10.
10. Sharma, P., & Singh, G. (2018). Dynamic analysis of outrigger systems in high rise building against lateral loading.
International Journal of Civil Engineering and Technology, 9(8), 61–70.