DESIGN & ANALYSIS OF RECTANGULAR RCC OVERHEAD WATER TANK

Data:

Size of water Tank 4.0m x4.0m x2.0m

Height of water tank from GL =8.0m

Water tank wall thickness =180mm

Size of column = 300 x 300 mm

Bracing beam =300 x 350mm

Concrete grade M30

Steel Fe 415 grade

1.Creation of Geometry :

File New Project Select Space Unit : Length =meters;

Force=KN; File Name=RCC overhead tank Next

Select Open Structure Wizard Finish.

Change to Frame Models from Truss models Select Bay frame and

double click on it.

Length X=4m No. bays =1

Height Y=10m No. of bays =3 click Bay 1=4m Bay2=4m Bay3=2m;

Width Z=4m No. bays=1

Apply Transfer model Click Yes Go to Front view icon (first view)

Select tank portion for surface modeling.

Isometric view Select surface meshing Quadrilateral meshing OK

Division=10 Apply . Do first bottom, side 1, side 2, side 3 and side 4. To

remove all beam elements, Select the tank portion except bottom of tank

Delete80 beams & associated Physical beams (if any) will be deletedOk.

Fig.1 Isometric view of the model

2. Member Properties :

Click General Define Rectangle YD=0.3m ZD=0.30m (column)

Add. YD=0.35m ZD=0.30m (Beams at top and bracing) Add Thickness Node

1 to 4 =0.18mAddClose.

High light column size 0.3 x 0.3 and select column portion by windowing

Assign to selected beam Assign Yes. High light beam size

0.35 x 0.30 and select tank bottom beam and tank middle bracing beam

Assign to selected beam Assign Yes. High light thickness and select tank

portion Assign to selected beam Assign Yes Close. De select the

member.

3.Supports :

Front view Click SupportCreate Fixed Add Click support 2 and bottom

most nodes of tank Assign to selected node AssignYes Close.

De select the nodes and change to beam cursor.

4. Loading :

Click Load & Definitions Click Load case details Add. Primary Number 1:

Loading type: none Title : load case 1 Add Close.

Click Load case 1Add.

For Bottom plate:

Click plate loads Pressure on full plate Pressure =-20 GYSelect

bottom plate of tank portion Assign to selected plates AssignYes .

Fig. 2 Bottom plate chosen

Fig. 3 Orientation of various sides of Plates

Left side wall:

Load case details Add.

Click plate loads Hydrostatic Select plates select left side plates

Done. W1 =-20 W2=-0.001 Y Local Z Add close.

Fig. 4 & 5 Left side plate chosen

Fig. 6 Left side plate load application

Fig. 7 Left side hydrostatic pressure diagram

Right side wall:

Load case details Add.

Click plate loads Hydrostatic Select plates Select right side plates Done.

W1 = 20 W2=0.001 Y Local Z Add Close.

Fig. 8 Right side plate chosen

Fig. 9 Rightside plate load application

Fig. 10 Rightside plate hydrostatic pressure application

Back side wall:

Load case details Add.

Click plate loads Hydrostatic Select plates select rear side wall plate Done.

W1 =- 20 W2= 0.001 Y Local Z Add Close.

Fig. 11 Back or rear side plate selection

Fig. 12 Rearside plate load application

Front side wall:

Load case details Add.

Click plate loads Hydrostatic Select plates Select front side wall plate

Done. W1=- 20 W2= 0.001 Y Local Z Add Close.

Fig. 13 Frontside plate selection in top view

Fig. 14 Frontside plate hydrostatic load application

5. Analysis Type :

Click Analysis/print No print Add. Click post print Define commands

Analysis Results Add Close. Save the file before run the Analysis.

6. Analysis :

From Main Menu ` Analysis Run Analysis Done.

7. Result :

Go to post processing mode.

Click deflection and see the deflection Diagram.

Fig.15 Deflection diagram in top view

Fig. 16 Deflection diagram

Fig. 17 Front view deflection diagram

ResultsPlate Stress contour Loads & Results Load case: Load case 1

Stress type: Mx (local) Ok.

Fig. 18 BMD Mx top view

ResultsPlate Stress contour Loads & Results Load case: Load case 1

Stress type: My(local) Ok.

Fig. 19 Stress contour My (local)

ResultsPlate Stress contour Loads & Results Load case: Load case 1

Stress type: Max. Von Mis.Ok.

Fig. 20 Max Von Mises

Fig. 21 Von mises Isometric view

ResultsPlate Stress contour Loads & Results Load case: Load case 1

Stress type: Max. Absolute Ok.

Fig. 22 Max Absolute

Fig. 23 Max Absolute top view

Fig. 24 Max BMD in plates

Maximum BMD Right click Plate stress contour Table.

Fig. 25 Max BMD

Fig. 26 Plate stress contour table

Fig. 27 Summary