Effectiveness of Reinforced Concrete Shear Wall for Multi-storeyed Building

Effectiveness of Reinforced Concrete Shear Wall for Multi-storeyed Building

P. S. Kumbhare1, A. C. Saoji2

1-Post Graduate Student in Structural Engineering, 2-Associate Professor, Civil Engineering Department, Babasaheb Naik College of Engineering, Pusad- 445215, Maharashtra

Sant Gadge Baba Amravati University, Amravati, Maharashtra 444602

Abstract

Shear wall is one of the most commonly used lateral load resisting in high rise building. Shear wall has high in plane stiffness and strength which can be used to simultaneously resist large horizontal load and support gravity load. The scope of present work was to study investigates the effectiveness of RC shear wall in medium rise building. The residential medium rise building is analyzed for earthquake force by considering two type of structural system. i.e. Frame system and Dual system. Effectiveness of shear wall has been studied with the help of four different models. Model one is bare frame structural system and other four models are dual type structural system. Analysis is carried out by using standard package ETAB. The comparison of these models for different parameters like Shear force, Bending Moment, Displacement, Storey Drift and Story Shear has been presented by replacing column with shear wall.

Keywords: – Frame Structure, Effectiveness, Shear Wall, Structural System, Muilt-storyed Building.

1. INTRODUCTION

   Reinforced concrete shear walls are used in building to resist lateral force due to wind and earthquakes. They are usually provided between column lines, in stair wells, lift wells, in shafts that house other utilities. Shear wall provide lateral load resisting by transferring the wind or earthquake load to foundation. Besides, they impart lateral stiffness to the system and also carry gravity loads.

   Reinforced concrete framed buildings are adequate for resisting both the vertical and horizontal load. However, when buildings are tall, beam and column sizes are quite heavy. So there is lot of congestion at these joint and it is difficult to place and vibrate concrete at these place and displacement is quite heavy which induces heavy forces in member. Shear wall behave like flexural members. They are usually used in tall building to avoid collapse of buildings. Shear wall may become imperative from the point of view of economy and control of lateral deflection. When shear wall are situated in advantageous positions in the building, they can form an efficient lateral force resisting system. In this present paper one model for bar frame type residential building and fore models for dual type structural system are generated with the help of ETAB and effectiveness has been checked.

2. BUILDING DISCRIBTION

   A Building considered is the residential building having (G+11) stories. Height of each story is 3.1m. Other details are given below.

   Zone III

   Response Reduction Factor 5

   Importance Factor 1

   Soil Condition Medium

   Height of Building 38.7 m

   Depth Of foundation 1.5 m Thickness of shear wall

   Size of Column:-

   Interior column 700mm x 700mm

   Side column 650mm x650mm

   Corner column 600mm x600mm

   Size of Beam 500mm x 500mm Thickness of slab 150 mm

   Thickness of Shear wall 200 mm

   Live Load 3 KN / m2

   Floor Finish 1 KN / m2

   Material Properties Concrete Grade M20 Steel Grade Fe 415

   Figure.1 : Structural Plane

3. MODELLING AND ANALYSIS

   Building is modeled using stander package ETAB. Beams and columns are modeled as two noded beam elements with six DOF at each node. Shear wall are modeled using shell element. Equivalent static analysis

   or linear static analysis is performed on models. Based on analysis result parameters such as bending moment, shear force in column, displacement, storey drift and storey shear are compared for each model. The following models have been considered.

   Model I :- Bare frame without shear wall.

   Model II :- Dual type structural system with one wall on each side.

   Model III :- Dual type structural system with corner shear wall.

   Model IV :- Dual type structural system with interior shear wall.

   Model V :- Dual type structural system with all side (Exte) shear wall.

   Figure. 2: Model I

   Figure.3 : Model II

   Figure.4 : Model III

   Figure.5 : Model IV

   Figure. 6 : Model V

4. RESULT AND DISCUSSION

   1. Lateral Displacement

      II

      III

      1 2 3 4 5 6 7 8 9 10 11 R

      Storey

      I

      25

      20

      15

      10

      5

      0

      Displacement(mm)

      Lateral Displacement of models at each floor level is shown in Fig. 7

      DISPLACEMENT

      IV

      Figure 7: Lateral Displacement

      From result observed that the displacement of Model II, Model III and Model IV reduced up to 20-50 % as compared with bare frame model. Where as in model V maximum displacement up to 5 times as compared with bare frame.

   2. Storey Drift

      Storey Drift for different models as shown in figure. 8.

      0.8

      Storey Drift (mm)

      0.7

      0.6

      0.5

      0.4

      0.3

      0.2

      0.1

      0

      1 2 3 4 5 6 7 8 9 10 11 12

      Storey

      SHEAR FORCE

      70

      60

      50

      40

      30

      20

      10

      0

      Shear Force (KN)

      I

      I

      II III

      V

      II III

      IV

      C1 C2 C3 C4

      Column

      V

      Figure 8: Storey Drift

      From result observed that drift is increased as height of building increased and reduced at top floor.

      Figure 10: Shear Force

      Bending Moment

   3. Storey Shear

      STOREY SHEAR

      Bending Moment (KNm)

      Storey Shear for different models are as shown in figure.9

      2500

      2000

      1500

      1000

      500

      0

      STOREY SHEAR

      160

      140

      120

      100

      80

      60

      40

      20

      0

      BENDING MOMENT

      C1 C2 C3 C4

      Column

      Figure 11: Bending Moment

      I II III V

      I II III IV

      V

      121110 9 8 7 6 5 4 3 2 1

      STOREY

      Figure 9: Storey Shear

   4. Bending Moment And Shear Force in column

      Maximum Bending Moment and shear force in column as shown in Fig. It is observed that shear force decreases up to 50-80 % in model II, model III, model V as compared to the bare frame nd bending moment up to 60-90 % decreases is observed.

5. CONCLUSION

From above results it is clear that shear wall frame interaction systems are very effective in resisting lateral forces induced by earthquake. For residential building shear walls can be used as a primary vertical load carrying element, thus serving the load and dividing space. The frame type structural system become economical as compared to the dual type structural

system can be used for medium rise residential building situated in high seismic zone.

REFERENCES

1. Anshumn. S, Dipendu Bhunia, Bhavin Rmjiyani (2011), Solution of shear wall location in Multi-storey building. International Journal of Civil Engineering Vol. 9, No.2Pages 493-506.

2. M. Asharaf, Z. A. Siddiqi, M. A. Javed, Configuration of Multi-storey building subjected to lateral forces. Asian Journal of Civil Engineering (Building & Housing), Vol. 9, No. 5 Pages 525-537.

3. Manoj S., Medhekar Sudhir K. Jain, Seismic behaviour design and detailing of RC shear walls, Part1:- Bhaviour and Strength. Indian Concrete Journal July 1993.

4. R.Sudarshan Brahma, Kaustubh Dasgupta, Influence of structural wall area ratio on seismic design of reinforced concrete wall-frame building, International Journal of Earth Science and Engineering, ISSN 0974-5904, Volume 04, No.06 SPL, 2011, Pages 560-564.

5. R. S. Londhe, A. P. Chavan, Behaviour of building frames with steel plate shear walls. Asian Journal of civil Engineering, Vol.11, No.1 (2010), Pages 95-102.

6. Shrikhande Manish, Agrawal Pankaj (2010), Earthquake Resistant Design Structures. PHI Learning Private Limited New Delhi.

7. Duggal S. K.(2010), Earthquake Resistant Design Structues. Oxfored University press YMCA library building, Jai Singh road, New Delhi.

8. Breau of India Standard, Is-1893, Part 1 (2002), Criteria for earthquake resistant design of structures. Part 1 General Provision and building, New Delhi, India.

9. Bureau of Indian Standard, IS-456(2000), Plain and Reinforced Concrete Code of Practice.