Design of Flat bottom Overhead Water tank

1. DESIGN OF OVERHEAD
CIRCULAR WATER TANK
WITH FLAT BASE
PRESENTED BY,
SYEDA NUSRATH FATHIMA

2. INTRODUCTION TO WATER TANKS
TYPES OF ELEVATED WATER TANKS
SUPPORT SYSTEM OR STAGING
DESIGN PRINCIPLES
DESIGN EXAMPLE
2
CONTENTS

3. To study the Analysis and Design of
elevated water tanks.
To study the guidelines for the design of
liquid retaining structure according to IS
Code IS: 3370 part 2-2009 & IS: 456:2000.
To know about the design philosophy for
the safe and economical design of water
tanks.
3
OBJECTIVES

4.  For storage of large quantities of water, tanks are required.
INTRODUCTION
WATER TANK
BASED ON
PLACEMENT OF
TANK
BASED ON
SHAPE OF
TANK
1. UNDER GROUND
2.RESTING ON
GROUND
3. ELEVATED
1. RECTANGULAR
2. CIRCULAR
3. INTZE
4. SPHERICAL
5. CONICAL

5.  Tanks used to supply water through gravity are
termed as Elevated water tanks.
 Elevated tanks may have circular or rectangular
section with flat or Conical bottom.
 For small Storage capacity, tanks square in plan are
economical. Where as for large capacities circular
tanks prove economical.
They may be made of masonry,
steel, reinforced concrete and pre
stressed concrete.
RCC tanks are very popular as,
 Simplicity in construction and design
 Cheap
 monolithic in nature
 Can be made leak proof.

6. IntzeCircular
Spherical bottom Domed bottom Conical bottom
Rectangular

7. 7
COMPARISON OF TANKS
RECTANGULAR
TANK
CIRCULAR TANK INTZE TANK
PRESTRESSED
TANKS
For smaller
capacities
rectangular
(square)
tanks are
economical.
For large capacities
circular tanks are
economical.
For same capacity, circular
tanks requires less concrete
than rectangular tanks.
On account of circular
shape, it can be made
water tight easily as there
are no sharp corners.
Intze tank is
constructed
to reduce the
project cost
because
lower dome
in this
construction
resists
horizontal
thrust
For bigger
tanks,
prestressing
is the
superior
choice
resulting in
a saving of
up to 20%.

8. Elevated tanks are supported on staging
which may consist of Masonry Shaft, R.C.C
tower or R.C.C. column braced together
with tie beams.
SUPPORT SYSTEM FOR RECTANGULAR TANKS
•The simplest form is
Rectangular tanks
supported by beams and
four columns.
•With increase in plan
area, Internal beams and
columns are introduced
to limit the span.

9. SUPPORT SYSTEM FOR CIRCULAR TANKS
 Circular beam
Masonry tower
 4 beams mutually orthogonal
2 beams mutually orthogonal
Internal beams and Columns
Single Annular shaft

11. Design of Tank
• Cover slab or Top dome
• Top ring beam
• Side walls or Cylindrical wall
• Base slab
Design of Staging
Design of Foundation
DESIGN OF ELEVATED WATER TANKS