Design of underground rectangular concrete water tank PDF

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DESIGN OF UNDER GROUND
RECTANGULAR CONCTERE WATER TANK DESIGN OF UNDERGROUND RECTANGULAR
CONCRETE WATER TANK
DESIGN OF UNDERGROUND RECTANGULAR
CONCRETE WATER TANK
DESIGN OF UNDERGROUND RECTANGULAR
CONCRETE WATER TANK
DESIGN OF UNDERGROUND RECTANGULAR
C...

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DESIGN OF UNDERGROUND RECTANGULAR CONCRETE WATER TANK PROJECT REPORT

Submitted by

ANIRUDHA.B

714013103004

PALANIAPPAN.RM

714013103029

REVANTH KUMAR.S

714013103037

SRIRAM.S

714013103045

in partial fulfillment for the award of the degree of

BACHELOR OF ENGINEERING in

CIVIL ENGINEERING

SRI SHAKTHI INSTITUTE OF ENGINEERING AND TECHNOLOGY COIMBATORE - 641062

ANNA UNIVERSITY: CHENNAI 600 025 OCTOBER 2016

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BONAFIDE CERTIFICATE Certified that this project report “DESIGN OF UNDER GROUND RECTANGULAR CONCTERE WATER TANK” is the bonafide work of “ANIRUDHA.B, PALANIAPPAN.RM, REVANTH KUMAR.S, SRIRAM.S” who carried out the project work under my supervision.

SIGNATURE

SIGNATURE

Er. M. Ravichandran

Dr. D. Karunanidhi

HEAD OF THE DEPARTMENT

SUPERVISOR

DEPARTMENT OF CIVIL

ASSISTANT PROFESSOR

ENGINEERING,

DEPARTMENT OF CIVIL

SRI SHAKTHI INSTITUTE OF

ENGINEERING,

ENGINEERING AND TECHNOLOG,

SRI SHAKTHI INSTITUTE OF

COIMBATORE-62.

ENGINEERING AND TECHNOLOGY, COIMBATORE-62

Submitted for the design project viva voce examination held on ……….at Sri Shakthi Institute of Engineering and Technology, Coimbatore-62.

Internal Examiner

External Examine

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ACKNOWLEDGEMENT First and foremost, we place this design project work on the feet of GOD ALMIGHTY who is the power of strength in each step of progress towards the successful completion of my project. We express deepest gratitude to our Chairman Dr. S. Thangavelu, for his invaluable guidance and blessings. We are very grateful to our Principal Dr. C. Natarajan, for providing us with an environment to complete this project successfully. We are very grateful to our Joint Secretary Mr. T. Sheelan and Director Dr. R. Manian, for the encouragement to complete our project successfully. We are deeply indebted to our Head of the Department Mr. S. Ravichandran, who molded us both technically and morally for achieving greater success in life. We are very grateful to our Supervisor Dr. D. Karunanithi, for being instrumental in the completion of my project with his valuable guidance. We are very thankful to our Project Coordinator Er. S. Ravichandran, who helped me in the completion of the project with his valuable guidance. We are also thankful to all the staff members of our college and technicians for their help in making this project a successful one. Finally, we take this opportunity to extend our deep appreciation to our Family and Friends, for all that meant to us during the crucial times of the completion of our project. ANIRUDHA.B PALANIAPPAN.RM REVANTH KUMAR.S SRIRAM.S

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TABLE OF CONTANTS CHAPTER NO

1.

TITLE

PAGE NO

LIST OF TABLE

vi

LIST OF FIGURES

vii

LIST OF SYMBOLS

viii

INTRODUCTION

1

1.1 UNDERGROUND WATER TANK

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1.2 IMPORTANCE OF UNDERGROUND

2

WATER TANK 1.3 DIFFERENT TYPES OF WATER TANKS

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DEPENDING ON ITS LOCATION 1.4 DIFFERENCE BETWEEN CIRCULAR AND

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RECTANGULAR WATER TANK 1.5 DIFFERENT TYPES OF WATER TANKS

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BASED ON MATERIALS 1.5.1 PLASTIC

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1.5.2 STEEL TANK

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1.5.3 FIBRE GLASS

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1.5.4 CONCRTE TANK

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1.6 ADVANTAGES OF CONCRETE WATER TANK

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1.6.1 COST

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1.6.2 DETERIORATION/LIFESPAN/

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DURABILITY 1.6.3 SIZE AND SHAPE

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1.6.4 ENVIRONMENT CREDENTIALS 8 1.6.5 MERITS OF CONCRETE WATER 9 TANK 1.6.6 DEMERITS OF CONCRETE

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WATER TANK 1.6.7 SITE PREPARATIONS 1.7 OBJECTIVES

2.

GENERAL DESIGN REQUIREMENTS

9 9

10

2.1 DESIGN REQUIREMENT OF WATER TANK 13 2.2 JOINTS IN LIQUID RETAINING

15

STRUCTURES 2.2.1 MOVEMENT JOINTS

15

2.2.2 CONTRACTION JOINTS

17

2.2.3 TEMPORARY JOINTS

18

2.2.4 SPACING OF JOINTS

18

2.3 FLOORS

20

2.4 WALLS

22

2.5 ROOF

24

2.6 MINIMUM REINFORCEMENT

25

2.7 FLEXIBLE BASE WATER TANK

26

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2.8 RIGID BASE TANK

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2.9 DESIGN REQUIREMENTS FOR UNDER

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GROUND WATER TANK

3.

ANALYSIS AND DESIGN

31

3.1 DETERMINATION OF FIELD DENSITY OF

31

SOIL BY CORE CUTTER 3.2 FIXED FUNNEL TEST

33

3.3 DESIGN OF RECTANGULAR

35

UNDERGROUND CONCRETE TANK

4.

CONCLUSION

49

5.

REFERENCE

50

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ABSTRACT Water tanks and reservoirs are used to store liquids like water, petroleum or chemicals. For any domestic and commercial purposes, water tanks are very basic need to meet their day to day use. In this project an attempt is made to design the rectangular underground tank, the tank is to maintain atmospheric temperature and provided optimum height for easy pumping of water to overhead tank. Since it is underground water tank the lateral earth pressure and water pressure also considered for the design calculations, so the design is to be carried out as per IS code norms. This project deals with analysis and design of under ground water tank of 2lakh liter capacity. The design in this project comprises of side walls, base slab and roof slab. The analysis and design of underground water tank is done using AutoCad. For this design project limit state method is used.

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LIST OF TABLES

TABLE NO.

TITLE

PAGE

2.1

PERMISSIBLE CONCRETE STRESS

12

3.1

FIXED FUNNEL TEST

34

3.2

BENDING MOMENT ON WATER FACE AND EARTH FACE

3.3

38

BENDING MOMENT AT CENTER AND SUPPORT

45

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LIST OF FIGURES FIGURE NO.

TITLE

PAGE NO

2.1

MOVEMENT JOINT

16

2.2

EXPANSION JOINT

17

2.3

SLIDING JOINT

18

2.4

CONTRACTION JOINT

18

2.5

TEMPORARY JOINT

19

2.6

SPACING OF JOINT

19

3.1

REINFORCEMENT OF PLAN

46

3.2

REINFORCEMNT OF SHORT AND LONG WALL

47

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LIST OF SYMBOLS φ - Angle of repose σcbc – Permissible stress in concrete in bending σst – Permissible stress in steel in tension jd – Lever arm depth m – Modular ratio d – Overall depth de – Effective depth b – Breadth W – Load at the structure M – Bending moment Mv – Bending moment at vertical direction Mh – Bending moment at horizontal direction At – Area of tensile steel L – Length of the tank B – Width of the tank H – Overall height of the tank

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CHAPTER 1 INTRODUCTION 1.1 UNDERGROUND WATER TANK Underground water tanks are structures which act as a reservoir for small domestic or commercial buildings. Basic components of underground water tanks are Base slab, Side walls, And Roof slab. Tanks are very ductile, enabling to withstand seismic forces and varying water backfill. Tanks utilize material efficiently – steel in tension, concrete in compression. Underground water tanks have Low maintenance throughout the life as these are built with concrete, durable material that never corrodes and does not require coatings when in contact with water or the environment. The main advantage of underground water tank is that the temperature is lower than the overhead tanks, which will reduce evaporation inside water tank. Underground water tank faces different type of loads compared to other structures, they mainly face horizontal or lateral loads due to earth pressure and water pressure or any liquid pressure which is been stored in the tank. The side walls of the underground water tank will face greater load at the bottom and the load linearly decreases towards the top. The underground water tank not only faces loads inside the tank it also has to bear the surcharge above the ground level. So the roof slab of the underground tank should have enough strength to with stand the surcharge.

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1.2 IMPORTANCE OF UNDERGROUND WATER TANK • Seepage It is very important to store water and not to lose it. The tank should have a durable, watertight, opaque exterior and a clean, smooth interior. Below ground tanks must also be plastered well and correctly installed, otherwise they can collapse.

• Evaporation All storage tanks should have a roof made from locally available materials. A tight fitting top cover prevents evaporation.

• Safety We should prevent mosquito breeding and keeps insects, rodents, birds and children out of the tank. A suitable overflow outlet(s) and access for cleaning are also important.

• Storage of water It is very imperative for all tanks to store water because the main process of the tank is to store water due to lack of running fresh water in all areas.

• Emergency Underground tanks are used as reservoirs where water is pumped to overhead tanks. When water is not available it will help us store and use water.

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1.3 DIFFERENT TYPES OF WATER TANKS DEPENDING ON ITS LOCATION (i)RESTING ON GROUND • Deals with normal pressure of gravity and corresponding outward pressure of water stored in water tank (Internal hydrostatic pressure) • Pipes can be attached directly for irrigation purpose. • Pumps can be attached depending on the usage. • More economical than other type of tanks. • No need for excavation. (ii)OVERHEAD • The water pressure to all the processes being supplied is held at a relatively constant level. • In power failure or pump failure pressure remains constant. • At work any pipe can be taken for maintenance. • If all the pumps are failed water pressure will be still for fire suppression and other critical needs. • Gravity plays an important role for the flow of water. • Columns are provided for the support of tank. (iii)UNDERGROUND • Used as water reservoir for irrigation purpose. • Used for rainwater harvesting. • Difficulty in installation.

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• It is protected from animals in forest areas. • Pumps are needed for supply of water. • Expensive compared to tanks resting on the ground. • In case of fire the water will be safe underground. 1.4 DIFFERENCE BETWEEN CIRCULAR AND RECTANGULAR WATER TANK. 1.4.1CIRCULAR: It is the simplest form of water tank. For the same amount of storage circular water tank requires less amount of materials compared to rectangular water tank. It has no corner and can be made water tight easily. It is economical for smaller storage of water up to 200000000 lits and with dia 5 to 8 m. Depth of the storage is between 3 to 4 m. The side walls are designed for hoop tension and bending moment. Round tanks is really a cylinder holding the water. Water exerts pressure equally in all directions. When place in cylinder round water vessels can be constructed using minimum thickness of wall. Circular water tanks can be transported and installed easily. Merits: Structural strength, Economic, Constant heat level, Clean and hygienic. 1.4.2RECTANGULAR: Rectangular tanks are modular, fit in most yards. Large tanks of high capacity can be constructed. It occupies less space compared to circular tanks. Multiple units of water storage can be constructed using rectangular type tanks. Merits: Occupy less space when multiple units used.

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Provide longer travel distance for settling to occur. 1.5 DIFFERENT TYPES WATER TANKS BASED ON MATERIAL: 1.5.1 PLASTIC TANK: Poly (plastic) water tanks are made from polyethylene; a UV stabilized food grade plastic. The tanks are light, you only need a sand base to place them on, and they come in a wide variety of colours and have a long serviceable life. Many poly tanks carrying a 25 year warranty, although many claim 15 years is a very realistic lifespan. They are also usually the second cheapest. One of the major disadvantages of polyethylene is the material is made from petrochemicals. Even after their serviceable life has ended, there's still a great big hunk of plastic that will take generations to break down and will release toxins as it does so. However, polyethylene tanks can still be easily recycled after 15 years, so it's just a matter of breaking the tank up and then carting it away rather than trying to squeeze a few more years out of one. Some poly tanks are made with a vertical seam - this is a weak point that may cause splitting and subsequent water loss. Polyethylene water tanks and fire don't really mix either - they'll just melt. This can be a real problem if you're in a rural area and you need that water to fight a fire. The other issue is the long term effects of drinking water stored for such a long time in this material. Polyethylene tanks are relatively new on the market, it is not known if there are any credible serviceable life studies that have been done in relation to these issues. Some people do note a bit of an odd taste to the water if the tank is placed in full sun. Just on that point - before purchasing a poly tank, check the warranty for temperature stipulations as some manufacturers will void the warranty if conditions where the tank is installed can get extremely hot.

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1.5.2 STEEL TANKS: Steel tanks Galvanized tanks have been around for over 150 years and are usually the cheapest type of tank. Hot-dip galvanizing is a process used to coat steel or iron with zinc. The Zinc helps slow down corrosion, but depending on environmental factors, a galvanized tank may last well under 5 years. This is due to electrolysis. Some metal tanks now also have polyethylene linings to further help retard corrosion - escaping plastic altogether can be a difficult thing to do these days. With a steel based tank, seriously consider the composition of the water you are storing and its potential to accelerate corrosion in any exposed metals. 1.5.3 FIBRE GLASS: Fibre glass, this is another long-lasting option that can be installed above or below ground. Fiberglass tanks resist corrosion and are not generally affected by chemicals. As fiberglass tanks tend to allow more light in than other types of tank materials, this can encourage the growth of algae, so they should be painted. Fiberglass can also tend to be brittle, leaving it prone to cracks - something you don't want, particularly in an in-ground situation. 1.5.4 CONCRETE TANK: Concrete water storage tanks can be built above grade or mostly hidden from view. They are built on site because of the material’s weight. Concrete is a porous material and needs to be sealed to prevent minerals leaching into the water. With proper sealing and construction techniques, this is can be addressed. Mining production and delivery of concrete is energy intensive. The advantage is achieved

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by its long life and its ability to be simply recycled. Choosing a tank material Choice is wonderful, but as you can see, there are advantages and disadvantages with each type of tank, particularly when it comes to environmental impact - so it's really a matter of gagging your needs and budget and then choosing the lesser of the evils. In regards to the financial side of things, bear in mind not just the initial cost, but how many times the tank will need replacing over X years. This also plays a role in the Concrete tanks have been used in rural areas for many years but are becoming more common in the city, particularly pre-cast underground concrete tanks that can be placed under driveways or front and back yards. The advantage of underground concrete tanks is that they can collect large volumes of water in properties tight for space that could not otherwise accommodate above-ground tanks. Houses with small gardens still consume large volumes of water internally through laundries, toilets and showers and could benefit from using underground concrete tanks for 'whole of house' water supply. 1.6 ADVANTAGES OF CONCRETE WATER TANK 1.6.1 COST: The actual concrete tank itself is generally only slightly more expensive than some steel options, however it becomes more expensive per litre when placing concrete tanks underground as excavation, transport and crane hire (for larger tanks) can be quite expensive. However, with rising land and water prices it may be a wise long-term investment for inner-city and small blocks, as an underground tank does not take up any valuable space on the property. See the Price Comparison for price estimates.

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1.6.2 DETERIORATION/LIFESPAN/DURABILITY: Concrete tanks are extremely durable and most purpose-built concrete rainwater tanks have plasticizers added for strength and are poured into a seamless mould to prevent leaks. Most manufacturers offer warranties of between 20 and 30 years, however a good quality concrete tank can last several decades. While not as easy to repair as steel or fiberglass tanks, leaking concrete tanks can be fixed with various sealants depending on the size of the crack and the position.

1.6.3 SIZE AND SHAPE: There are more and more companies producing pre-cast concrete tanks in many shapes and sizes including rectangular ones that fit neatly under driveways. Underground concrete tanks can also be cast on site (in situ). Most concrete tanks, whether pre-cast or built on site, are designed to be load bearing and are therefore ideal for placing under driveways. Water quality: Some older concrete tanks may leach lime, increasing the pH of water and affecting its taste. However, in most cases the water quality from concrete tanks is very good. Concrete tanks tend to keep the water cooler than most other tanks, reducing the likelihood of bacterial growth.

1.6.4 ENVIRONMENTAL CREDENTIALS: Concrete tanks have high embodied energy; however a good quality concrete tank will have a long life-span and can be recycled at the end of its life.

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1.6.5 SITE PREPARATION: Concrete tanks are extremely heavy and therefore some settling tends to occur once put in place. The use of packing sand or cracker dust is recommended and it may be worth rolling or compacting the sand before installing the tank to reduce initial movement. It is advisable to allow the tank to settle for a number of weeks before connecting fixed plumbing. Of resources used.

1.6.6 MERITS OF CONCRETE WATER TANK • When rain water is stored it reduces its acidity. • Concrete water tanks can with stand bush fire. • Keeps water cool. • Free from algae up to 100 years. • Lasts longer.

1.6.7 DEMERITS OF CONCRETE WATER TANK • Leakage • Leaching • Expensive

1.7 OBJECTIVES The objective of this project is to plan and design a underground concrete water tank for 2,00,000 liter capacity for Sri Shakthi institute of engineering and technology.

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