Effect of Wind on RC Structure Resting on Sloping Ground and Analysis Done using ETABS

Effect of Wind on RC Structure Resting on Sloping Ground and Analysis Done using ETABS

Details for Structure Report and Analysis

Jiss Treesa Gijo

Department of Structural & Construction Management Mangalam College of Engineering

Kottayam, Kerala

Gokul P V

Assistant Professor

Department of Structural & Construction Management Mangalam College of Engineering

Kottayam, Kerala

Abstract In this paper , effect of wind on RC structures is considered which are resting on sloping grounds with different inclinations and analysis is done using ETABS. Wind loads are considered . Here 5 different wind speeds are considered along with 3 different sloping ground and analysis is done .Results are formed in terms of shear force

,moment, displacement which are mainly analysed to quantify various impacts of sloping ground.

The project work examines the structural behavouir of building in sloping geometery .In this study a G+8 storey building is analysed on varying sloping angles with degrees 0,10,15.

KeywordSloping ,inclinations, RC structure

1. INTRODUCTION

   Wind load is considered to be one of the important design load structures .Therefore it is important to study the behaviour of wind in buildings and this should be included in academic study. Structural are design to resist earthquake, wind load and stable the structure and the damage in the structure. In GIS (Graphical Information Systems) applications, calculation of ground slope is considered to be a traditional application. There are many methods for calculating slope. In military,scientific and civilian analysis slope is an important component. Manual slope generation, based upon contour line information and is one of the established and generally accepted method.The paper deals the analysis, design is done by using the software called as E-TABS. E-TABS is 3D structural software. E- TABS is the abbreviation of Extended 3D Analysis of Building System. In IS 875: part 3- 1987 analytical method is given. This method is usually acceptable for regular buildings and is almost based on the geometrical properties of the building and does not depend on others.

2. MATERIAL AND GEOMETRICAL

   PRROPERTIES

   1. Material Properties

      Following are the material properties taken in modelling Density of RCC : 25 KN/m³ Density of

      Masonry : 18.5KN/m³

      The typical storey height floor to floor is 3m .The sections of columns are considered 350*350 mm with section beam size of 350*350

   2. Loading Conditions

      1. Dead Load : self wt.of slab considering 150 mm thick

         Floor finish load = 1 KN/m³

         Infill Load : 0.10*3*1805=5.55 kN/m

         1. Live loads : live load on typical floors

            =3 KN/m^2

         2. Wind load : calculation of wind load as per IS-CODE- 875 (PART 3)1987

   3. Equations

   The design wind pressure can be calculated by, Pd = Kd+Ka+Kc+Pz.

   Kd = wind directionality factor Ka

   =Area averaging factor Kc= Combination Factor .

   While Kd, Kc ,Pz can be calculated with the help of table created in excel sheets

   F = Cf+Ae+P ( As per IS 875 part 3:1987)

   Effective area calculations ,A1 =3*3=9m^2 A2=3*1.05=4.5m^2

   ISSN: 2278-0181

   ICART – 2022 Conference Proceedings

3. SCOPE AND OBJECTIVE

   The scope of the present study is to design and analysis of G+8 building for finding the effect of wind on the structure on different sloping ground and to find the results.

4. MODELLING

   9m*9m in plan area and 8 storeys high

   • TYPE A: 24 meter building height model , 0 degree inclined footing level

   • TYPE B: 24 meter building height model , 5 degree inclined footing level

   • TYPE C: 24 meter building height model , 10 degree inclined footing level

     FIG 1 :0 Degree sloping

     FIG 2: 5 Degree sloping

     FIG 3 : 10 Degree sloping

     Table 1: max shear force in columns

     Slop e	Velocity
     	33	39	44	47	55
     0	27	38.9 6	49.5	56	77.2
     5	40.1 2	53.9 8	66.8 9	74.9 5	100
     10	52.9 5	70.9 8	89	101	136.0 1

     FIG 4 : Typical wall loads

     Slope	Velocity
     	33	39	44	47	55
     0	40	55.65	71.01	80.98	109. 96
     5	41.98	56.32	71.96	82.42	112
     10	51.96	73.01	91.86	104.32	144. 65

     FIG 5 : Slab finishes

     Table 2: max moment in columns

     Slope	Velocity
     	33	39	44	47	55
     0	21.65	29.72	38	43	59.2
     5	21.65	29.72	38.12	43.98	60.21
     10	21.65	29.72	38.98	44.32	61.2

     Graph 1: shear force Vs velocity

     Shear Force Vs Velocity

     150

     100

     50

     0

     0

     5

     velocity

     10

     Shear Foce

     Table 3 : max displacment in columns

     velocity at 33

     velocity at 44

     velocity at 55

     velocity at 39

     velocity at 47

     Moment

     Graph 2 : Moment Vs Velocity

     Moment Vs Velocity

     160

     140

     120

     100

     80

     60

     40

     20

     0

     0

     5 10

     velocity

     velocity at 33

     velocity at 44

     velocity at 55

     velocity at 39

     veelocity at 47

     Storey displacement Ve- locity

     70

     60

     50

     40

     30

     20

     10

     0

     0

     velocity at 33

     velocity at 44

     velovity at 55

     Displacement

     Graph 3 : displacement Vs velocity

     FIG 6 : 33 Wind 5D Drift

5. RESULT

   • Maximum shear force in building increases with increase in wind velocity and least effect by the influence of shear force for increase the ground slope

   • Maximum shear force in column increases with increase in ground slope.

   • Maximum moments in beam does not get affected by increase in ground slope or sloping angle.

     5

     Velocity

     10

   • Maximum moments in column increases with increase in wind velocity as well as ground slope

   velocity at 39

   velocity at 47

6. REFERENCES

[1] Umesh R Biradar, Shivraj Mangalgi, Seismic Response of Reinforced ConcreteStructure by Using Different Bracing System, Internatioal journal of research and technology, vol 3, Issue 09, 2014.

[2] G Ajay Kumar ,A.G (2019) Seismic Analysis of RC High Rise Building with Shear Walls at Diverse Locations .International Journal of Innovative Technology anfd Engineering ,7,9113-9117

[3] Apurva Arjun Gaikwad ,D.A.B .P(2019). Sesimic Analysis of Low Rise ,High Rise,Mid Rise Rcc structure on Sloping Ground International Research Journal Of Engineering and Technology.

[4] Eurocode -8 Design of Structures for Earthquake Resistance.

[5] IS:1893 -2016 Criteria for earthquake resist design and of structure [6] spectrum analysis of a G+4 building with mass irregularity on a sloped surface. IOP Conference Series: Materials Science and

Engineering,1070(1).

[7] IS 875 Part-2Code of practice for design loads (other than earthquake) for buildings andstructures.