A

PROJECT REPORT
ON
DESIGN, SEISMIC ANALYSIS AND ESTIMATE OF
RESIDENTIAL BUILDING WITH RAINWATER
HARVESTING
Submitted for the partial fulfillment of the Degree of Bachelor of
Engineering in Civil Engineering awarded by Pokhara University

SUBMITTED BY
Binaya Lal Lamichhane (11520124)
Khagendra Bohara (11520137)
Mahesh Paudel (11520142)
Mohan Raj Neupane (11520143)

SUPERVISOR
Er. DEEPAK THAPA

DEPARTMENT OF CIVIL ENGINEERING

POKHARA ENGINEERING COLLEGE
Phirke, Pokhara 8
2014

CERTIFICATE
Date: January 26,
2015
This is to certify that the project entitled Design, Seismic Analysis and
Estimate of Residential Building with Rainwater Harvesting has been
carried out by BINAYA LAL LAMICHHANE (11520124), KHAGENDRA
BOHARA (11520137), MAHESH PAUDEL (11520142), MOHAN RAJ NEUPANE
(11520143), in partial fulfillment of the degree of Bachelor of Engineering in Civil
engineering of Pokhara University during the academic year 2010. To the best of our
knowledge and belief, this work has not been submitted elsewhere for the of any other
degree and thus has been accepted.

------------------------------Er. Binod Prasad Dhakal

External Examiner
------------------------------Er. Deepak Thapa
Supervisor

------------------------------Er. Yam Bahadur Thapa

Head of the Department, Civil Engineering

-----------------------Er. Saroj Giri

Chef. Research and Development

ACKNOWLEDGEMENT
We, the final year BE students, are highly obliged to Pokhara Engineering
College for providing us such a great opportunity to the research in our related field
and build a project of our own interest. The duration of completing this project has
been a great opportunity for us to explore the possibilities of different ideas in our
field.
First of all we would like to thank Department of Civil Engineering and
creditable teachers who were invaluable for our project. We would also like to convey
our deep sense of gratitude to HOD of civil department Er. Yam bahadur Thapa and
R&D Chief Er. Saroj Giri for their great support and guidance during the project
We are genuinely grateful to our project supervisor Er. Deepak Thapa for his
co-operation and guidance throughout the project and reviewing our project from time
to time. We are indebted to our teachers who helped us with our project by sharing
their precious suggestion, instructions and experiences.
Our strength was the support of the friends who have directly and indirectly
encouraged and assisted us in carrying out this work. Their constructive criticism and
motivation is the key to our success.

Team members:
Binaya Lal Lamichhane (11520124)
Khagendra Bohara (11520137)
Mahesh Paudel (11520142)
Mohan Raj Neupane (11520143)

PREFACE
A course entitled "Civil Engineering Project" is prescribed by the Pokhara
University as a practicing of case study and helping tool to get familiar with the
practical problems that every professional has to face in their Professional life.
This project is the practical use of the theoretical knowledge that we acquire during
the four years, of Civil Engineering course with application of knowledge we gained
from our respectable teachers and supervisor.
To fulfill the requirement of the course we have chosen the Project Design ,seismic
Analysis

and

Estimate

of

Residental

Building

with

Rainwater

Harvestingin Kaski District. Besides loads like live load, dead load, consideration
for earthquake load is the distinguishing feature of this report. The report to various
books like Reinforced concrete: A.K.Jain and Design aids for Reinforced concrete to
IS: 456 2000.The analysis is done by using computer program SAP2000 and Limit
state method. This course really helped us while designing the structure and provides
us the knowledge to design safe, economic, stable and efficient structure.
During the project work we got to know thoroughly that how to analyze the
problem and get the optimal result which will safe guard the lives of the people and
structure itself in the state of seismic disasters.
This project work also helped us to work with Team spirit and coordination for the
long-term work and getting through the problems effectively.
In gist, it was a real enthusiasm and self satisfaction to work under the guidance of
our project advisor Er. Deepak Thapa who always guided us with valuable tips while
tackling the problem and gave in-depth knowledge of Structural & Earthquake
Engineering. We believe that his valuable guidance will always help us in our future
professional life.

ABSTRACT
This project work was intended to learn the structural analysis and seismic resistant
design of residential building with rainwater harvesting to be located at Pokhara. This
report includes all the works regarding analysis, design, drawing and structural
detailing of earthquake resistance residential building. We are focused on structural
analysis and design of four storey framed structure. Material properties are assumed
as per the common practice and similarly the soil bearing capacity is also assumed
suitably. It was mainly based on the manual design of all structural elements for the
analyzed computer output using different design codes as per requirement. In case of
Rainwater Harvesting feasibility was studied and designed in detail.
The analysis, design and detailing of all structural member is required to complete the
entire design but due to unavailability of time only calculation for the design of
critical member is presented here.

TABLE OF CONTENT
TITLE

PAGE NO

Acknowledgement
Preface
Abstract
CHAPTER 1 INTRODUCTION
1.1 Background

1.2 Statement of Problem

1.3 Literature Review

1.4 Objectives of Project

1.5 Significance of Project

1.6 Limitation of Project

1.7 Methodology
1.7.1 Requirement
1.7.2 Site Visit

4
4

1.7.3 Preliminary Design

1.7.4 Analysis

4
4

1.7.5 Design

1.7.6 Drawing and Design

1.7.7 Rainwater Harvesting System

1.8 Time Schedule

CHAPTER 2 PRILIMINARY DESIGN

2.1 Development of Architectural Plan

2.2 Assessment of load

2.2.1 Dead loads

2.2.2 Live loads

2.2.3 Eccentricity of Vertical load

2.2.4 Lateral load

2.2.5 Estimation of Earthquake load

2.2.6 Load Combination

10

2.3 Loading Pattern

11

2.4 Determination of Preliminary thickness of Slab

12

2.5 Determination of Preliminary size of Beam

13

2.6 Determination of Preliminary size of Column

13
4

CHAPTER 3 ANALYSIS OF BUILDING

3.0 Method of Analysis
3.1 Earthquake Analysis
3.1.1

Seismic Coefficient Method

3.1.1.1 Horizontal Seismic Base Shear

3.2 Load Calculation
3.3 Design
3.4 Detailing
CHAPTER 4 RAINWATER HARVESTING
4.1 Introduction
4.2 Why Rainwater Harvesting
4.3 Application Areas
18
4.4 Criteria of Selection of Rainwater Harvesting Technologies
4.5 Components of Rooftop Rainwater Harvesting System
4.6 Basis of Concrete Water Tank design
4.7 Storage Tank for reservoir
4.8 First flush and filter screens
4.9 Rainwater Harvesting Efficiency
CHAPTER 5 DETAILED DESIGN
5.1 Slab
5.2 Beam
5.3 Column
5.4 Footing
5.5 Staircase
5.6 Rainwater Harvesting
5.6.1 Base for floor slab
5.6.2 Minimum Reinforcement for Water Tank
CHAPTER 6 CONCLUSION
CHAPTER 7 BIBLIOGRAPHY
APPENDIX-B DRAWINGS

14
14
14
14
15
15
15
17
18
19
19
22
22
23
23
25
31
33
39
42
47
52
52
53
54

SAP output Drawing

Archectural Drawing
Detailing of RCC members

NOTIFICATIONS
Symbols Description
Ac = Area of concrete
Ag = Gross area of the section
Ast = Area of the tensile section
Ast1 = Area of balanced tensile steel
Ast2 = Area of tensile steel in excess of the balanced steel
Asc = Area of compression steel
Asv = Area of vertical stirrups
5

BM = Bending moment
B = Breadth of beam or shorter dimension of rectangular column
bf = Effective width of flange section
bw = Breadth of the web in T or L section
c = Coefficient depending upon the flexibility of the structures that depend on number
of storey and time period (t)
D = Overall depth of the beam or slab longer dimension of column
DL = Dead load
LL = Live load
= Diameter of the bar
d = Effective depth of the bar
d= Effective cover
Df =Thickness of the flange T or L section
emin=Minimum eccentricity
ex, ey=Eccentricity about X and Y axis respectively
EL= Earthquake load
Ec= Youngs modulus of elasticity of concrete
Es =Youngs modulus of elasticity of steel
max= Maximum stress
min=Minimum stress
ck= Characteristics compressive strength of concrete
y= Characteristics yield strength of steel
sc =Design stress in compression steel at the level of centroid of compression steel
cc=Design stress in concrete at the level of centroid of compression
I =Importance factor of the structure
Ix, Iy= Moment of inertia about X and Y axis respectively
hi= Height of the first floor above base of the frame
K = Performance factor depending upon the structural framing system and for
brittleness or ductility of the construction
leff=Effective length of element
lx=Span of the slab in the shorter direction
ly =Span of the slab in the longer direction
l = Unsupported length or clear span of elements
Lo= Distance between points of inflection
LL = Live load
6

Mu =Factored moment, designed moment for limit state design

Mu,lim=Maximum uni-axial moment capacity of the section with axial load
Mux = Factored moment axis about X-X axis
Muy= Factored moment axis about Y-Y axis
Mux1= Maximum uni-axial moment capacity of the section with axial load, bending
about maximum uni-axial moment capacity of the section with axial load, bending
about X-axis
Muy1= Maximum uni-axial moment capacity of the section with axial load, bending
about maximum uni-axial moment capacity of the section with axial load, bending
about Y- axis
P = Axial load in the element
Pu= factored axial load, designed axial load for the limit state design
Pc = Percentage of compression reinforcement
Pt=Percentage of tension reinforcement
Qi =Base shear distributed in the ith floor
Sv= Spacing of stirrup
S = Spacing of the main bar
T =Estimated natural or fundamental time period of the building in seconds
V = Shear force
Vu =Design shear force for limit state, factored shear force
Vus=Strength of shear reinforcement in the limit state design
Vb=Total base shear
Wi=Lump load on the ith floor
Xu=Depth of the natural axis at the limit state of the collapse
Xu,max=Maximum depth of the neutral axis in the limit state design
Zx, Zy= Section modulus along respective axis
h=Design horizontal seismic coefficient
o=Basic horizontal seismic coefficient
x, y =Coefficient for moment in slab
bd=Design bond stress
c=Shear strength of concrete
c =Maximum shear strength of concrete with shear reinforcement
v= Nominal shear stress
Ast= Area of Reinforcement
MOR= Moment of Resistance
7

BM= Bending Moment

CHAPTER 1
INTRODUCTION
1.1
Background
Today, Pokhara is one of the most urbanizing city of Nepal with building construction.
Nowadays, with the awareness level of the building owners increasing than in the
past, the trend of having a building analyzed scientifically before it is actually
constructed , which is a good thing because such practice helps construction of more
safer buildings which can eventually lead to avoidance of loss of lives and property in
case of a structural failure.

Our site is located in the north east side of Pokhara valley, within mixed
populated. It is near Janapriya Multiple College; Ratna Chowk. It
enhances the better chances of our project to be implemented in the field
without any rejection. Also the place is in windward direction so our site could
be beneficial with better air circulation. People near the building site are
literate and many of them own a business or are engaged in government jobs.
For the water supply system pipes are distributed by Nepal water supply
Corporation available over there. The site is linked with the highway so
locally available materials are easily transported to the site.

Types of residential buildings (American Standard)

-Apartment block
-Asylum
-Condominium
-Dormitory
-Duplex
-villa
-Bungalow
-Micro house

Our building falls under micro house. It is a dwelling that fulfills all the
requirements of habitations (shelter, sleep, and cooking, heating, toilet) in a very
compact space. These are quit common in densely populated cities in Asia.
Structural Analysis deals with analyzing these internal forces in the members of the
structures. Structural Design deals with sizing various members of the structures to
resist the internal forces to which they are subjected during their effective life span.
Unless the proper Structural Detailing method is adopted the structural design will be
no more effective. The Indian Standard Code of Practice should be thoroughly
adopted for proper analysis, design and detailing with respect to safety, economy,
stability and strength.
This project work has been undertaken as a partial requirement for Bachelors Degree
in Civil Engineering (B.E.). This project work contains structural analysis, design and
detailing of a residential building with Rainwater Harvesting system, located in Kaski
District. All the theoretical knowledge on analysis and design acquired on the course
work are utilized with practical application. The main objective of the project is to
acquaint in the practical aspects of Civil Engineering. We, being the budding
engineers, are interested in such analysis and design of structures will help us in
similar jobs that might be in our hands in the future.
Due to above mention circumstances we are enthusiastic to choose such a topic.
1.2
-

Statement of Problem
Due to the rapid urbanization and increase of construction work in the valley,
the design engineers are unable to supervise in the field in during construction
work, which degrades the desired quality.

The structural design of earthquake resistive building is difficult to implement

as per designed.

Nepal government is unable to provide adequate water supply. About 30%

water demand is covered by boring. Besides rainfall water is also not used.

1.3 Literature Review

For the literature review we are familiar with building design, foundation engineering,
estimating, survey and experience from survey camping which built confidence to
drive this project.
2

Besides this project is made with reference to the national building code (NBC
2060) , IS-SP16, IS 456-2000 and for Earthquake resistant Design of structure (IS
1893-2002). Loads like live load, dead load, consideration for earthquake load is the
distinguishing feature of this report. The report to various books like Reinforced
concrete: A.K.Jain and Design aids for Reinforced concrete to IS: 456 2000.The
analysis is done by using computer program SAP2000 and Limit state method. This
course really helped us while designing the structure and provides us the knowledge
to design safe, economic, stable and efficient structure According to IS 1893:2002,
Pokhara lies on Vth Zone, the severest one. Hence the effect of earthquake is predominant than the wind load. So, the building is analyzed for Earthquake as lateral
Load. The seismic coefficient design method as stipulated in IS 1893:2002 is applied
to analyze the building for earthquake. Special reinforced concrete moment resisting
frame is considered as the main structural system of the building.
The project report has been prepared in complete conformity with various stipulations
in Indian Standards, Code of Practice for Plain and Reinforced Concrete IS 456-2000,
Design Aids for Reinforced Concrete to IS 456-2000(SP-16), Criteria Earthquake
Resistant Design Structures IS 1893-2000, Ductile Detailing of Reinforced Concrete
Structures Subjected to Seismic Forces- Code of Practice IS 13920-1993, Handbook
on Concrete Reinforcement and Detailing SP-34. Use of these codes have emphasized
on providing sufficient safety, economy, strength and ductility besides satisfactory
serviceability requirements of cracking and deflection in concrete structures. These
codes are based on principles of Limit State of Design.For Rainwater Harvesting BC
Punima and Rainwater Tank Design and installation hand book 2008 was referred.

1.4 Objectives
The main objectives of our project are to:

1.5

Designing of earthquake resistive residential building.

Design of Rainwater Harvesting System.

Significance of the Project

The major significance of the project is to learn & develop the skill of structural
analysis, design and develop the self-confident. We think this project will strengthen
our knowledge of the structure design, design of rainwater harvesting system and it
3

will ease us to work in future. It covers the development of architectural plan,

structural analysis, detail design and design of rain water harvesting system.
1.6

Limitation of the Project

Due to lack of instrument and lab soil test and additional test were not
conducted.

Due to unavailability of rainfall data of 10 years, we have designed the

rainfall water collection of 1 year only.

1.7
1.7.1

Rainwater harvesting water treatment system is not designed.

Methodology
Requirement

A serious discussion is carried out with the client about all the requirements ( size and
placement of room ). Blue print of the land is studied in detail.
1.7.2

Site Visit
The buildings designed in the locality are considered. The availability of land

is also analyzed for the design of the residential building.

1.7.3

Preliminary Design

Loading pattern from slab to beam is obtained by drawing 45 0 offset lines from each
corner. Then obtained trapezoidal as well as triangular loading are converted into
equivalent UDL as described in respective section.
In case of beam the ratio of breadth and depth should be greater than 0.6 where,
depth is obtained from the load acted upon per meter length .
Thickness of column is 50 mm greater than that of breadth of beam. Loads are
considered as per codes.
1.7.4

Analysis

Structural grids are analyzed from different load combinations. The entire grids are
for the calculation manually also analysis is done using SAP 2000.

1.7.5 Design

The building structure has following important components like footing, column,
beam and slab. Each of these components can be designed by using various methods:

Working stress method

Ultimate load method

Limit state method

The working stress design method is based on the consideration of

combine elastic limit of steel and concrete and the factor of safety is provided in
stresses of steel and concrete. Since, there is more strength of materials beyond elastic
limit i.e. the strength exists up to ultimate strength, so the full strength is not utilized,
thus requiring more material. The factor of safety in stress of steel and concrete is
taken more. Hence, this method seems uneconomical. Also the consideration of elastic
behavior of concrete is incorrect.
However in ultimate strength, the section is designed up to the ultimate
strength of material (concrete and steel). Here the factor of safety is provided on
working load (1.5 for dead load and 2.2 for live load). In this method thus the full
strength of material is utilized making the design uneconomical. Utilizing the full
strength of material is utilized making the design economical. Utilizing the strength of
material results in smaller of structural members making them slender and hence there
is more chances of deflection.
The limit state of design is done to overcome the drawbacks of both working
stress method and ultimate strength method. The design is based on considering the
full strength of material, thus providing FOS for both stress as well as load. The FOS
for the stress of steel is 1.15 and that for the concrete are 1.5 respectively and FOS for
working load is 1.5. This method there by seems economical as it utilizes full strength
of material and also considers for deflection of structural members section
1.7.6

Drawing and detailing

Auto CAD 2007 is used for the drawing design and detailing of various
components(beam, slab, column staircase) of the proposed building.
1.7.7

Rainwater Harvesting System

Rainfall data is collected from Department of Hydrology & Meteorology, and water
tank is designed accordingly.
5

1.8 Time Schedule

Task

SN
1

Preliminary survey

& site selection

Planning &

preliminary design
Structure analysis &

detail design
Prepare architectural

drawing
Detail estimating &

2 3

Weeks
3 4 1 2

rate analysis
6

Design of Rainwater
Harvesting

7
8

Prepared final report

Presentation of final
project
TOTAL TURATION

CHAPTER - 2
PRELIMINARY DESIGN
2.1 Development of Architectural Plan
For slab preliminary design is done according to deflection criteria. Thumb
rule basis is adopted to consider the preliminary design of beam section. Preliminary
design of column is done considering an interior column. For load acting in the
column, live load decrease according to IS 456:2000. However the rectangular
column is generally preferred in the building structure, hence rectangular column
section is adopted in this building project. Preliminary design of column is done
considering an interior column. Preliminary criteria for a building to be earthquake
resistive are: plan should be regular, mass distribution should be regular, adjacent
building should have same floor height. Similarly, the position of the pillar is
considered according to the length of the room and aviability of space. The space of
the room is designed according to the requirement of the client.

2.2 Assessment of Loads

2.2.1 Dead Loads
These are choosing by IS 456. The correct assessment and calculation of dead loads
is the most important first step. This can be done precisely if the architectural
drawings are complete and include the roof, ceiling, floor and wall finishes, parapets
and railings, overhead water storage tanks place on the roof: position, thickness and
specification of fixed partitions, panel walls, cladding walls etc. Often after-thoughts
alterations and additions result in the overloading of certain 10 components or the redesign of the structure. Such situations should be avoided by careful initial planning.
The correct sizes of structural member i.e. slab beams and columns, cannot be
ascertained before the structural the structural analysis and design are finalized. Thus,
some sizes need to be assigned by experience and architectural to begin with, checked
and modified during preliminary design and finalized during detailed analysis and
checking.

2.2.2 Live Loads

These are to chosen from the cods such as IS: 875(part 2) for various occupancies and
IS: 875 (part 4) for snow load conditions were required. These codes permit certain
modifications in the load intensities where vary large contributory areas are involved
or when the building consist of large number of storey. For economy design such
reduction should be utilized. Lateral and vertical loads on parapets and railings and
higher load intensities on entrance halls, stairs must be duly considered. It will be
useful to mark the design load classes for intensities on small plans of the building to
begin with.
2.2.3 Eccentricity of Vertical Loads
When transferring the loads from the parapets, partition wall, cladding walls etc. to
the supporting beams and columns, the eccentricity associated with this loads should
be properly considered. In the case of rigid frames of reinforced concrete, such
eccentricities will produce externally applied joint moments similar to those arising
from projecting cantilevers and this should be included in the frame analysis.
2.2.4. Lateral Loads
Lateral load acting in the building is earthquake load and wind load. But in the
context of this building project, wind load is not severing, hence only seismic load is
carried out.
2.2.5 Estimation of Earthquake Loads
At the preliminary stage, the design seismic lateral forces may be worked out
based on pseudo-seismic coefficients of design response spectra using an approximate
fundamental natural period of the building using simple empirical expression (refer to
IS : 1893-1894 sections 3,4 and clause 4.2.1.1 notes 1,2). Seismic coefficient method
considers the calculation of base shear of the building considering different factors. It
also considers each storey as lumped mass system and distributes the base shear to all
lumped mass systems.
According to IS 1893 (Part I): 2002 Cl. No. 6.4.2 the design horizontal seismic
coefficient Ah for a structure shall be determined by the following expression:
Ah

Z I Sa
2R g

Where,
Z = Zone factor given by IS 1893 (Part I): 2002 Table 2, Here for Zone V, Z =
0.36
I = Importance Factor, I = 1 for commercial building
R = Response reduction factor given by IS 1893 (Part I): 2002 Table 7, R = 5.0
Sa/g = Average response acceleration coefficient which depends on
Fundamental natural period of vibration (Ta)= 0.09.
According to IS 1893 (Part I): 2002 Cl. No. 7.4.2
Ta

0.09 h
d

Where,
h = height of building in m, h = 11.75 m
d = Base dimension of the building at the plinth level in m along the considered
direction of the lateral force.
Now, calculating natural time period of vibration
Ta=0.09h/d
Tx=0.0911.75/(13.386)^0.5= 0.289038

Ty=0.0911.75/(12.17)^0.5=

0.303134

For soil type III (Soft Soil) Sa/g = 0.36

Now,
Ah

0.36 x 1 x 2.5
2x5

0.09

10

According to IS 1893 (Part I) : 2002 Cl. No. 7.5.3 the total design lateral force or
design seismic base shear (VB) along any principle direction is given by
VB = Ah x W
Where, W = Seismic weight of the building
According to IS 1893 (Part I): 2002 Cl. No. 7.7.1 the design base shear (V B)
computed above shall be distributed along the height of the building as per the
following expression:
Qi VB

Wi h i2
n

Wj h 2j

j1

Where,Qi = Design lateral force at floor i

Wi = Seismic weight of floor i
hi = Height of floor I measured from base
n = No. of storeys in the building
2.2.6 Load Combination
For limit state design in RCC structure and pre-stressed concrete the possible
load combinations taken for analysis and design are given below:

Dead Load (DL)

11

Live Load (LL)

Earthquake load in X (EQx) static

Earthquake load in Y (EQy) static

Following load combination as per IS 1893(Part I):2002 are adopted:

i.

1.5(DL + LL)

ii.

1.2(DL + LL + EQx)

iii.

1.2(DL + LL - EQx)

iv.

1.2(DL + LL + EQy)

v.

1.2(DL + LL - EQy)

vi.

1.5(DL + EQx)

vii.

1.5(DL - EQx)

viii.

1.5(DL + EQy)

ix.

1.5(DL - EQy)

x.

0.9DL+1.5EQx

xi.

0.9DL-1.5EQx

xii.

0.9DL+1.5EQy

xiii.

0.9DL-1.5EQy

2.3 Loading pattern

Loading pattern from slab to beam is obtained by drawing bisecting angle from each
corner. The obtained triangular or trapezoidal loadings are converted into equivalent
uniformly distributed load in the following way:
D

Cr crack

Pattern

A
A

B
B

12

L
Loading intensity per unit length, w = DL or LL of slab peHere ABCD is a Slab and
AB, BC, CD, DA are beams respectively.
w

Trapezoidal Loading pattern in Beam AB

r sq. unit * h
w

Triangular Loading Pattern on Beam B

2.4 Determination of Preliminary thickness of Slab
Slabs are plate elements forming floors and roofs of building and carrying
distributed loads primarily by flexure. Inclined slabs may be used as ramps for
multistory car parks .Staircases can be considered as inclined slabs. A slab may be
supported by beams or walls or continuous over one or more supports. One-way Slabs
are those in which the length is more than twice the breadth. A one way slab can be
simply supported or continuous. When slabs are those supported on four sides, two
way spanning action occurs. Such slabs may be simply supported or continuous on
any or all sides. The deflections and bending moments in a two way slab are
considerably reduced as compared to those in a one way slab. A two way slab may be
considered to consist of a series of interconnected beams. We have designed the two
edges discontinuous side two slab for the thickness using mathematical relation
L

d
Slab
Maximum ly

= 4325mm
13

Adopt effective depth d = 100mm

Overall Depth D

=125mm

2.5 Determination of Preliminary size of Beam

All the required internal forces obtained analysis was compared and analyzed to
design the required safe section. To make easy workmanship during construction and
to make the design more practical, we have considered a ling continuous beam in a
grid. All the positive and negative maximum moments for all design combinations
were taken for a complete continuous beam in a grid. Maximum of those positive and
negative moments in all combinations were compared to get the maximum positive
and negative moments. The required reinforcement was calculated from those
moments.
Along Length of Building
Longest span

= 4325 mm

Depth

= 450 mm

Width

= 300 mm

Size of beam

= 450 mm x 300 mm

2.6 Determination of Preliminary size of Column

Column is a structural element that supports axial loading but a compressive member
subjected to pure axial loading occurs rare in practice. So, all columns are subjected to
axial as well as moments occurred due to eccentricity or (due to end restraints
imposed by monolithically placed beams or slabs). The strength of columns of
materials shape and size of cross-section length and degree of positional and linear
directional restraints at ends.The column size is designed considering the column
which has maximum stress (axial load, positive moment and negative moment).
Column
Size

= 350mm*350mm,

P%

= (0.8 4)%,

Cover

= 35mm

14

CHAPTER - 3
ANALYSIS OF BUILDING
3.0 Method of Analysis
SAP 2000 Non Linear is adopted as the basic tool for the analysis of the
structure and this program is based on finite element method. The stresses and
displacement of various structural elements of the building are obtained using this
program which is used for the design of the members. Staircases are analyzed
separately. IS 1893-2002 (part 1) is followed for the seismic analysis of the building.
The fundamental time period of the structure is calculated as specified in code.

3.1 Earthquake Analysis

The earthquake forces are mainly calculated by two methods

Seismic coefficient method

Modal response spectrum method

3.1.1 Seismic Coefficient Method

Seismic coefficient method is further classified into two categories:
3.1.1.1 Horizontal Seismic Base Shear
The total design lateral force or design seismic base shear VB along any
principal direction shall be determine by following expression
VB = Ah x W
Where, W = Seismic weight of the building
Ah

Z I Sa
2R g

Where,
Z = Zone factor given by IS 1893 (Part I): 2002 Table 2, Here for Zone V, Z =
0.36
I = Importance Factor, I = 1 for commercial building
R = Response reduction factor given by IS 1893 (Part I): 2002 Table 7, R =
15

5.0
Sa/g = Average response acceleration coefficient which depends on
Fundamental natural period of vibration (Ta)= 0.09.

3.2 Load Calculation

Earthquake Load Calculation:

3.3 Design
16

Limit state method is used for the design of RC elements. The design is used
based on IS 456-2000, IS SP-16, IS SP-34 etc. The following materials are adopted
for the design of elements
Ordinary Portland Cement (OPC)
Grade of concrete M20 for all concrete structures.
Grade of reinforced steel Fe415 for longitudinal and lateral bar.
3.4 Detailing
The detailing of the reinforcement and its presentation on drawing is an art. The
drawing should show all shape and dimensions clearly without any ambiguity (see SP
34-1987 section 4). The seemingly inconspicuous hooks, bends overlaps and
anchorage length of bars are actually extremely important for the safety of the
members and must be shown meticulously where required. Splices of the bars are
particularly weak spots and should be clearly specified and detailed on the drawings.
When specifying large diameter main bars of long members, it will be preferable to
use more positive means of connection such as welding, bolt nut system rather than
lap splices.
A bar bending schedule (SP: 34, section 5) is an important piece of information on the
drawings which will avoid misunderstanding of the reinforcement drawings and
ensure the accurate and complete installation of the specified bars. Certain special
reinforcing with controlled spacing and bar bending details are required from the
ductility point of view in seismic zones over and above those required by IS 456:2000
for general purposes. Structural layout should be simple, symmetrical regular (mass,
stiffness, geometry). Change in stiffness from floor to floor should be gradual. There
will be minimum offset of beam and columns. Amount of tensile reinforcement in
beam should be restricted and more compression reinforcement should be provided.
Stirrups should be provided at close interval to prevent buckling of rods and to ensure
confinement of concrete.

17

18

CHAPTER - 4
RAINWATER HARVESTING
4.1 Introduction
Rainwater harvesting is a technology used to collect, convey and store rain for later
use from relatively clean surfaces such as a roof, land surface or rock catchment. The
water is generally stored in a rainwater tank or directed to recharge groundwater.
Rainwater infiltration is another aspect of rainwater harvesting playing an important
role in storm water management and in the replenishment of the groundwater levels.
Today, rainwater harvesting has gained much on significance as a modern, watersaving and simple technology.
The practice of collecting rainwater from rainfall events can be classified into two
broad categories: land-based and roof-based. Land-based rainwater harvesting occurs
when runoff from land surfaces is collected in furrow dikes, ponds, tanks and
reservoirs. Roof-based rainwater harvesting refers to collecting rainwater runoff from
roof surfaces which usually provides a much cleaner source of water that can be also
used for drinking.
Gould and Nissen-Petersen (1999) categorized rainwater harvesting according to the
type of catchment surface used and the scale of activity (Figure 1).

Fig. 1. Small-scale rainwater harvesting systems and uses (adapted from Gould
and Nissen-Petersen, 1999).
19

Rooftop rainwater harvesting at the household level is most commonly used

for domestic purposes. Pokhara is the city with highest rainfall intensity in the
country. Due to the rapid urbanization population has been increasing day by day
which has caused the scarcity of water. To overcome this scarcity of water rainwater
harvesting can be the milestone for people living in Pokhara. It will definitely help in
fulfilling the adequate need of water. It is popular as a household option as the water
source is close to people and thus requires a minimum of energy to collect it. An
added advantage is that users own, maintain and control their system without the need
to rely on other community members.
4.2 Why rainwater harvesting?
In many regions of the world, clean drinking water is not always available and
this is only possible with tremendous investment costs and expenditure. Rainwater is
a free source and relatively clean and with proper treatment it can be even used as a
potable water source. Rainwater harvesting saves high-quality drinking water sources
and relieves the pressure on sewers and the environment by mitigating floods, soil
erosions and replenishing groundwater levels. In addition, rainwater harvesting
reduces the potable water consumption and consequently, the volume of generated
wastewater.
4.3 Application areas
Rainwater harvesting systems can be installed in both new and existing
buildings and harvested rainwater used for different applications that do not require
drinking water quality such as toilet flushing, garden watering, irrigation, cleaning
and laundry washing. Harvested rainwater is also used in many parts of the world as a
drinking water source. As rainwater is very soft there is also less consumption of
washing and cleaning powder. With rainwater harvesting, the savings in potable water
could amount up to 50% of the total household consumption.

20

4.4 Criteria for selection of rainwater harvesting technologies

Several factors should be considered when selecting rainwater harvesting systems for
domestic use:
type and size of catchment area
local rainfall data and weather patterns
family size
length of the drought period
alternative water sources
cost of the rainwater harvesting system.
4.5 Components of a rooftop rainwater harvesting system
Although rainwater can be harvested from many surfaces, rooftop harvesting
systems are most commonly used as the quality of harvested rainwater is usually
clean following proper installation and maintenance. The effective roof area and the
material used in constructing the roof largely influence the efficiency of collection
and the water quality.
Rainwater harvesting systems generally consist of four basic elements:
(1) a collection (catchment) area
(2) a conveyance system consisting of pipes and gutters
(3) a storage facility, and
(4) a delivery system consisting of a tap or pump.
Figure 2 shows a simple schematic diagram of a rooftop rainwater harvesting system
including conveyance and storage facilities.

21

Fig. 2: A schematic diagram of a rooftop rainwater harvesting system.

(1) A collection or catchment system is generally a simple structure such as roofs
and/or gutters that direct rainwater into the storage facility. Roofs are ideal as
catchment areas as they easily collect large volumes of rainwater.
The amount and quality of rainwater collected from a catchment area depends upon
the rain intensity, roof surface area, type of roofing material and the surrounding
environment. Roofing materials that are well suited include slates, clay tiles and
concrete tiles. Generally, unpainted and uncoated surface areas are most suitable. If
paint is used, it should be non-toxic (no lead-based paints).
(2) A conveyance system is required to transfer the rainwater from the roof
catchment area to the storage system by connecting roof drains (drain pipes) and
piping from the roof top to one or more downspouts that transport the rainwater
through a filter system to the storage tanks. Materials suitable for the pipework
include polyethylene (PE), polypropylene (PP) or stainless steel.
Before water is stored in a storage tank or cistern, and prior to use, it should be
filtered to remove particles and debris. The choice of the filtering system depends on
22

the construction conditions. Low-maintenance filters with a good filter output and
high water flow should be preferred. First flush systems which filter out the first
rain and diverts it away from the storage tank should be also installed. This will
remove the contaminants in rainwater which are highest in the first rain shower.
(3) Storage tank or cistern to store harvested rainwater for use when needed.
Depending on the space available these tanks can be constructed above grade, partly
underground, or below grade. They may be constructed as part of the building, or may
be built as a separate unit located some distance away from the building.
The storage tank should be also constructed of an inert material such as reinforced
concrete, ferrocement (reinforced steel and concrete), fibreglass, polyethylene, or
stainless steel, or they could be made of wood, metal, or earth. The choice of material
depends on local availability and affordability. Various types can be used including
cylindrical ferrocement tanks, mortar jars (large jar shaped vessels constructed from
wire reinforced mortar) and single and battery (interconnected) tanks. Polyethylene
tanks are the most common and easiest to clean and connect to the piping system.
Storage tanks must be opaque to inhibit algal growth and should be located near to the
supply and demand points to reduce the distance water is conveyed.
Water flow into the storage tank or cistern is also decisive for the quality of the cistern
water. Calm rainwater inlet will prevent the stirring up of the sediment. Upon leaving
the cistern, the stored water is extracted from the cleanest part of the tank, just below
the surface of the water, using a floating extraction filter. A sloping overflow trap is
necessary to drain away any floating matter and to protect from sewer gases. Storage
tanks should be also kept closed to prevent the entry of insects and other animals.
(4) Delivery system which delivers rainwater and it usually includes a small pump, a
pressure tank and a tap, if delivery by means of simple gravity on site is not feasible.
Disinfection of the harvested rainwater, which includes filtration and/or ozone or UV
disinfection, is necessary if rainwater is to be used as a potable water source.

23

4.6 BASIS OF CONCRETE WATER TANK DESIGN

One of the vital considerations for design of tanks is that the structure has
adequate resistance to cracking and has adequate strength. For achieving these
following assumptions are made:

Concrete is capable of resisting limited tensile stresses the full section of

concrete including cover and reinforcement is taken into account in this
assumption.

To guard against structural failure in strength calculation the tensile strength of

concrete is ignored.

Reduced values of permissible stresses in steel are adopted in steel are adopted
in design.

4.7 Storage tanks or reservoirs

The storage reservoir is usually the most expensive part of the rainwater harvesting
system such that a careful design and construction is needed. The reservoir must be
constructed in such a way that it is durable and watertight and the collected water
does not become contaminated.
All rainwater tank designs should include as a minimum requirement:
- a solid secure cover - a coarse inlet filter
4 - an overflow pipe - a manhole, sump, and drain to facilitate cleaning - an extraction
system that does not contaminate the water, e.g. a tap or pump.
Storage reservoirs for domestic rainwater harvesting are classified in two categories:
1. surface or above-ground tanks, most common for roof collection, and
2. sub-surface or underground tanks, common for ground catchment systems.
Materials and design for the walls of sub-surface tanks or cisterns must be able to
resist the soil and soil water pressures from outside when the tank is empty. Tree roots
can also damage the structure below ground.
The size of the storage tank needed for a particular application is mainly determined
by the amount of water available for storage (a function of roof size and local average

24

rainfall), the amount of water likely to be used (a function of occupancy and use
purpose) and the projected length of time without rain (drought period).

25

4.8 First flush and filter screens

The first rain drains the dust, bird droppings, leaves, etc. which are found on the roof
surface. To prevent these pollutants from entering the storage tank, the first rainwater
containing the debris should be diverted or flushed. Automatic devices that prevent
the first 20-25 litres (20%) of runoff from being collected in the storage tank are
recommended.

Screens to retain larger debris such as leaves can be installed in the down-pipe or at
the tank inlet. The same applies to the collection of rain runoff from a hard ground
surface. In this case, simple gravel-sand filters can be installed at the entrance of the
storage tank to filter the first rain.
4.9 Rainwater harvesting efficiency
26

The efficiency of rainwater harvesting depends on the materials used, design and
construction, maintenance and the total amount of rainfall. A commonly used
efficiency figure, runoff coefficient, which is the percentage of precipitation that
appears as runoff, is 1.
For comparison, if cement tiles are used as a roofing material, the year-round roof
runoff coefficient is about 75%, whereas clay tiles collect usually less than 50%
depending on the harvesting technology. Plastic and metal sheets are best with an
efficiency of 80-90%.
For effective operation of a rainwater harvesting system, a well designed and carefully
constructed gutter system is also crucial. 90% or more of the rainwater collected on
the roof will be drained to the storage tank if the gutter and down-pipe system is
properly fitted and maintained. Common materials for gutters and down-pipes are
metal and plastic.

27

CHAPTER - 5
DETAIL DESIGN
5.1 Slab
Panal A ( Two Edges Discontinuous Side)
Ly = 4325mm

Ly 4325
=
=1.0740
LX 4050

Lx= 4050mm
2

So, two way slab.

Thickness of Slab
L

d
,

4050

d

4050
d
26 1 1.4

, d=

4050
36.4
d=11.263 mm

Load Calculation
Assume thickness of slab = 125 mm
Dead load of slab = 25 0.125 1 = 3.125 KN
Live load for slab = 3 KN/m2
Floor Finish = 1 KN/m2
Partition Wall = 1 KN/m2
Total Load = 3.125 + 3 +1 +1 = 8.125 KN/m2
Factored load (W) = 1.5 8.125 = 12.1875 KN/m2
From Table 26 , ( IS 456: 2000)
For Two edge Discontinuous Side,
x+ 0.0385
x 0.0419

y+ 0.035
y 0.047

Mx+ = w lx2 x+
= 12.1875 (4.050)2 0.0385
28

= 7.696 KN-mm
Mx- = w lx2 x= 12.1875 (4.050)2 0.0419
= 7.696 KN-mm
My+ = w ly2 y+
= 12.1875 (4.325)2 0.035
= 7.97 KN-mm
My- = w ly2 y= 12.1875 (4.325)2 0.047
= 10.714 KN-mm
Mmax = 10.714 KN-mm
Check of Depth
Mmax = 0.138 fck b d2
Or, 10.714 106 = 0.138 20 1000 d2
Or, 3881.88 = d2
d = 62.30 mm

111.263 mm

Hence, ok

Therefore, adopt thickness of slab D = 125 mm

Reinforcement Calculation
Y direction
fy Ast
Mu = 0.87 fy Ast d [1- fck b d ]
415 Ast
Or, 10.714 106 = 0.87 415Ast 125 [1- 20 1000 125 ]
Or,

10.714 10 6
41531.26

= Ast 0.000166Ast2

Or, 0.000166Ast2 - Ast + 237.396 = 0

Ast = 247.57 mm2
Check for Minimum Ast
Ast min = 0.12%bD
0.12

= 100
1000 125
= 150 mm2
Provide 8mm diameter bar giving area
D2
.ast =
4

29

3.14 8 8
4

= 50.24 mm2

ast
Spacing ( Sv) = 1000 Ast
=

1000 50.24
247.57

= 202.93mm 210 mm
1000 50.24
Provided Ast =
210
= 239.23 mm2

30

Ve reinforcement in X direction at edge strips

415 Ast

6
Or, 8.376
10 = 0.87
415
Ast
125
[1- 20 1000 125 ]
8.376 10 6
41531.26

Or,

= Ast 0.000166Ast2

Or, 0.000166Ast2 - Ast + 185.59 = 0

Ast = 191.68 mm2
Provide 8mm diameter bar giving area
D2
.ast =
4
=

3.14 8 8
4

= 50.24 mm2

ast
Spacing ( Sv) = 1000 Ast
=

1000 50.24
191.68

= 262.10mm 270 mm
1000 50.24
Provided Ast =
270
= 186.07 mm2
Reinforcement in mid stirrups span of X direction

415 Ast
Or, 7.696 106 = 0.87 415 Ast 125 [1- 20 1000 125 ]
7.696 106
41531.26

Or,

= Ast 0.000166Ast2

Or, 0.000166Ast2 - Ast + 170.52 = 0

Ast = 175.64 mm2
Provide 8mm diameter bar giving area
D2
.ast =
4
=

3.14 8 8
4

= 50.24 mm2
31

ast
Spacing ( Sv) = 1000 Ast
=

1000 50.24
175.64

= 286.03mm 290 mm
1000 50.24
Provided Ast =
290
= 173.24 mm2
Reinforcement in mid stirrups of Y direction
415 Ast
Or, 7.97106 = 0.87415Ast125[1- 20 1000 125 ]
7.97 106
41531.26

Or,

= Ast 0.000166Ast2

Or, 0.000166Ast2 - Ast + 176.59 = 0

Ast = 182.09 mm2
Provide 8mm diameter bar giving area
D2
.ast =
4
=

3.14 8 8
4

= 50.24 mm2

ast
Spacing ( Sv) = 1000 Ast
=

1000 50.24
182.09

= 175.90mm 180 mm
1000 50.24
Provided Ast =
180
= 279.11 mm2
Check for Shear
Shear force at the face of support
w lx
V=
2
=

12.1875 4.050
2

= 24. 678 KN/m

32

Nominal Shear (

v =

V
bd

24.769
1000 125

= 0.000197 KN/mm2
= 0.197 N/mm2
Percentage of Tensile Steel
1000 Ast
P =
b D

1000 125

1000 150

= 0.12%
Shear Strength of M20 concrete for 0.12% steel
c = 0.24 N/mm2
c = k c
= 1.30.28

= 0.364 N/mm2

Hence , ok

Therefore the slab is safe in shear.

Check for Development Length

Ld=

s
4 b d

0.87 415
4 1.6 1.2

= 47
Also,
Ld

1.3 M 1
+ L0
V

If 50% bars are curtail o.15L from centre A.

50 100
=50
Ast=
mm2
100
33

fy Ast
M1 = 0.87fyAstd[1- fck b d ]
415 50
M1 = 0.8741550125[1- 20 1000 125 ]

M1 = 22.37106 N-mm
w lx
V=
2
=

12.1875 4.050
2

= 24. 678 KN/m

= 24670 N/m
Assume L0= 200 mm
1.3 M 1

+ L0
Ld
V
47

1.3 22.37 10 6
+200
24670

=29.33

10 mm
Hence, Safe ok

5.2 Design of Beam

Let us take:
Member: - Beam 30

(location co-ordinate

X = 6.81 , y=0 , z= 3.25)

Grade of concrete: M20

Grade of steel: Fe 415
Factored moment (Mu) = 242.59 KN-m
Mu = 242.59KN-m @ A negative moment
M = 0.87yAstd
242.59106 = 0.87415Ast475
Ast = 1414.53 mm2
Astmin = 0.87bd/y
= 0.87300475/415
= 298.73 mm2< 1343.8 mm2
Therefore,
No. of bars = 6 20mm dia
34

This reinforcement is provided distance 1/6 in left hand side

Astactual = 1884 mm2
At section B positive moment
M = 0.87y Astd
41.180106 = 0.87415Ast475
Ast = 240.12 mm2
No. of bars = 1 20mm dia
Ast(actual) = 314mm2
This reinforcement is provided up to distance in left hand side
At end negative moment
M = 0.87y Astd
229.47106 = 0.87415Ast475
Ast = 1338.03mm2
Astmin = 298.73 mm2 < 1338.03 mm2
No. bars bar = 6 20mm
Astactual = 1884 mm2
Check development length
Ld = 47m
Ld M1/V + Lo
Ld 242.5914106/52.63103 + 0
Ld 98.1mm
Hence provided dia. is 20mm which is less than 98.1mm
Hence the section is safe in development length.
Check for maximum reinforcement
Astmax = 4% of bD
= 0.04300500
= 6000mm2
Maximum Ast provided = 1884mm2< 6000mm2
Hence the section is safe.
5.4 Column Design
5.4.1 Column Design(COMBO 1)
CASE 1 (Pmax)

35

Maxiumum stress at column no . 21

Size = 350350
Axial Load PU =862.288 KN

(max)

M ux=1.107 KN m
M uy=4.5281 KN m
L = 2.7432+0.125 = 2.8682m
Leff 2868.2
=
350
350
e

= 8.19 < 12 Short Column

Leff D
+
= 500 30

e min x

2868.2 350
+
500
30

= 17.40 mm

e min y

2868.2 350
+
500
30

= 17.40mm

M ux

= Pe
= 862.2880.0174 = 15KN-m

M uy

= Pe
= 862.2880.0174 = 15KN-m
M ux

= 15KN-m

M uy

= 15KN-m

Assume , P=2

P
2
= =0.1
ck 20
Assume

d ' 35
=
=0.1
D 350

36

Pu
862.288 103
=
= 0.35
F ck bd 20 350 350

Pu 2
= =0.1
F ck 20
Now from chart 44, Sp-16

M ux
F ck b D2

=0.13

uy 1= f ck ck b d2
M ux 1 =M
0.13 20 350 350 2
111.475 KN m

Puz=0.45 F ck A c + 0.75 F y A sc
Puz=0.45 20 ( 35020.02 3502 ) +(0.75 415 0.02 3 502)
1843012.5 N
= 1843.0125KN
Pu
862.288
=
=0.46
Puz 1843.0125
n

M
M
( ux ) +( uy ) 1
M ux 1
M uy 1
For value of

Pu
=0.46 chart we get n =0.43(interpolating)
Puz

Check,

37

 ,(

0.43
0.43
15
15
) +(
) 1
111.475
111.475

0.84 1 Ok
Since, Manual calculation accepts 2 % area of steel without eccentricity, But SAP
2000 calculated with eccentricity so, so we prefer the SAP analysis.
According To SAP 2000;

Section = 350350

% of Steel =2%
2
Area of Steel = 0.02 350 350=2450 = mm

8no. Bar 20,

P= 2513.27 mm2 >2450 mm2

Ast

5.4.2 Column Design(COMBO 1)

CASE 2(Mxmax)
Maxiumum stress at column no .21

Size = 350350
Axial Load PU =660.497 KN
M ux=89.6679 KN m
M uy=24.9818 KN m
L = 2.7432+0.125 = 2.8682m
Leff 2868.2
=
350
350
e

= 8.19 < 12 Short Column

Leff D
+
= 500 30

e min x

2868.2 350
+
500
30

= 17.40 mm

38

e min y
M ux

2868.2 350
+
500
30

= 17.40mm

= Pe
=660.4970.0174 = 11.49KN-m

M uy

= Pe
=660.4970.0174 = 11.49KN-m
M ux

= 89.6679KN-m

M uy

= 24.9818KN-m

Assume P=2
P
2
= =0.1
ck 20
d ' 35
=
=0.1
D 350

Assume

Pu
660.497 10
=
= 0.26
F ck bd 20 350 350
Pu
F ck =

2
20 =0.1

Now from chart 44, Sp-16

M ux
F ck b D2

0.16

When b = D,
uy 1= f ck b d
M ux 1=M

0.16 20 350 350 2

137.2 KN m

39

Puz =0.45 F ck A c + 0.75 F y A sc

Puz=0.45 20 ( 35020.02 3502 ) +(0.75 415 0.02 3 502)

= 1843.0125KN
Pu
660.497
=
=0.35
Puz 1843.0125

M ux
M
) +( uy ) 1
M ux 1
M uy 1

For value of

Pu
=0.35 chart we get n=1.1
Puz

Check,
,(

89.6674 1.1 24.9818 1.1

) +(
) =0.78 1
137.2
137.2

0.78 1Ok
Since, Manual calculation accepts 2 % area of steel without eccentricity, But
SAP 2000 calculated with eccentricity so, so we prefer the SAP analysis.
According To SAP 2000;

Section = 350350

% of Steel =2%
2
Area of Steel = 0.02 3 50 3 50 = 2450 mm
2

8no. Bar 20,

P= 2513.27 mm >2450 mm
Ast

Maxiumum stress at column no .21

CASE 3(My max)
Size = 350350
Axial Load PU =607.188 KN

40

M ux=17.3363 KN m
M uy=82.5954 KN m
L = 2.7432+0.125 = 2.8682m
Leff 2868.2
=
350
350
e

= 8.19 < 12 Short Column

Leff D
+
= 500 30

e min x

2868.2 350
+
500
30

= 17.40 mm

e min y

2868.2 350
+
500
30

= 17.40mm

M ux

= Pe
=607.1880.0174 = 10.56KN-m

M uy

= Pe
=607.1880.0174 = 10.56KN-m
M ux

= 17.3363KN-m

M uy

= 82.5954KN-m

Assume P=2
P
2
= =0.1
ck 20
Assume

d ' 35
=
=0.1
D 350

Pu
607.188
=
=
0.24
F ck bd 20 350 350
Pu
F ck =

2
20 =0.12

41

Now from chart 44, Sp-16

M ux
F ck b D2

0.16

When b = D,
uy 1= f ck b d
M ux 1=M

0.12 20 350 3502

102.9 KN m
Puz=0.45 F ck A c + 0.75 F y A sc
Puz=0.45 20 ( 35020.02 3502 ) +(0.75 415 0.02 3 502)
= 1843.0125KN
Pu
607.188
=
=0.32
Puz 1843.0125

M
M
( ux ) +( uy ) 1
M ux 1
M uy 1
For value of

Pu
=0.35 chart we get n=1.1
Puz

Check,

,(

17.3363 1.1 82.5954 1.1

) +(
) =0.92 1
102.9
102.9
0.78 1Ok

Since, Manual calculation accepts 2 % area of steel without eccentricity, But SAP
2000 calculated with eccentricity so, so we prefer the SAP analysis.
42

According To SAP 2000;

Section = 350350

% of Steel =2%
2
Area of Steel = 0.02 3 50 3 50 = 2450 mm

8no. Bar 20,

P= 2513.27 mm2 >2450 mm2

Ast

5.4 Foundation Design

Foundations are structural members/ elements that transfer loads from the building to
the earth. Loads are to be properly transmitted and foundations must be designed to
prevent excessive settlement or rotation, to minimize differential settlement and to
provide adequate sliding and overturning reaction forces for the stability.
For the choice of footing, comparative study was done of different designs to identify
the most economical and safe foundation. Following factors were considered for the
purpose:

Type of Structure

Type of Load

Bearing Capacity of Soil

Economy

5.4. ISOLATED SQUARE FOOTING

Bearing capacity of soil =200kN/mm2 (from soil investigation report)
Column size

=350mm x 350mm

M20 and Fe415

Step 1
43

Calculating of footing area

P=862.288 (axial load)
So factored load=862.288/1.5=574.85KN
Area of footing

= P / BCS

P = service load + 10% of sevice load.

=1.1 574.85
= 632.335=640KN
AF= 640 / 200
= 3.2m2

AF

Size of footing =

3.8

= 1.78

1.8 m

Provide 1.8m x 1.8m footing

Area of footing = 1.8 x 1.8 = 3.24 m2 > 3.20 m2
Net pressure acting upward due to factored load,
B C S = Factored load / Area of footing
=
=
1.

(574.85)/ 3.24
177.42KN /m2

Calculation of bending moment,

In case of isolated footing maximum bending moment occues at face of column
(x-x),
Mmax= BCS B ( L/2 l/2)2 1/2
= (177.42 1.8)(1.8 /2 - 0.35/2)2 1/2
= 83.93=85KN m

2.

Thickness of footing :-

Mmax = 0.36 fck b xm (d - 0.42xm)

85 106 = 0.362018000.48d(d- 0.420.48d)
d = 130.82 mm (Increased by 1.5 to 2times)
Adopt d = 200, clear cover =50 mm
Overall depth (D) = 200+50=250 mm
3.

Calculation of reinforcement:-

Mu = 0.87 fyAst (d Ast fy /Fck B)

44

85 106 = 0.87 415 Ast (250 415Ast / 20 1800)

Ast = 986.57 mm2
Provide 12 mm bar;
At1 =( 122) / 4 = 113.09 mm2
Spacing (S) = (1800 113.09) / 986.57
= 207.87 mm
Provide 12 bar @ 200 c/c
Ast provided = (1800113.09) / 200
= 1017.81mm2>Ast provided (ok)
4. Check for one way shear:Maxm SF occurs at a distance dfrom face of column,
Vu = 177.42 2 [1.8/2-0.35/2-0.25]
=168.55 KN
Nominal shear stress (

) = Vu / Bd

=(168.55 1000)/ (1800250)

=0.37 N/ mm2
Pt = 100 Ast / bd
= (100 1017.81 ) /(1800250) = 0.22
For, Pt 0.22 and M20,

0.336

c=

For depth, d=250, K = 1.1

' = K

= 1.10.336 =

'>

'=0.36 N/mm2

OK)

5. Check For Two Way Shear:Critical section for two way shear is at d/2 from face of column.
Vu = 177.42 [1.81.8-(0.35+0.25)2]
= 510.96KN
Nominal Shear Stress:-

45

= Vu / 4bd

=[ (510.96 1000) / 4(0.35+ 0.25)250 1000] = 0.85N/mm2

'

= Ks

Ks = (0.5 + Bc)>1,

= 0.25 Fck

{clause 31.6.3.1 pg no-58)

Bc= length of shorter side/length of larger side =1

Ks = (0.5 +1) = 1.5>1
So, Ks =1

6.

= 0.2520 = 1.12N/mm2

' =1 1.12 = 1.12N/mm2

' >

c ,

so OK.

Check For Development Length:-

Ld. = (0.87 fy) / (4 bd)

= (0.8712415) / (41.61.2)

[clause 26.2.1,pg no-42]

=564 mm
Provided embedded length = L-l / 2 clear cover
= [(1.8-0.35)/2] 0.05
= 0.675 =675 mm >Ld.

Hence OK.

5.5 Staircase
The purpose of the staircase is to provide pedestrian access between two
vertical floors of a building. The geometrical shapes and forms of staircase may be
different depending upon the requirement.

Staircase Design
Superimposed load = 5 KN/m2
ck =20 N/mm2
y =415 N/mm2
Solution;
Thickness waist slab =0.125m
Dead load of Flight
Step Section =1/20.1750.250 =0.0218 m2
46

Inclined section

= 0.3050.125 = 0.038 m2

Total area

= 0.0218+0.038 =0.0598m2

Density of Concrete = 25KN/m2

DL of step section 1m in width and 250mm in plan length
=0.059825

= 1.495 KN/m

DL per m2 on plan =1.495/0.250

= 5.98 KN/m2

Floor Finish per m2on plan

=1.2KN/m2

Live Load per m2 on plan

=3KN/m2

Total Load = 10.18 KN/m2

Factored Load

=15.27 KN/m2

=1.5 10.18

Taking 1.150m width of slab load = 1.15015.27 = 17.56 KN/m

For Loading: A
Self weight of Slab

= 0.125 25

Floor finish

= 1.2KN/m2

= 3.125 KN/m2

Live Load

= 3 KN/m2

Total Load

=7.325 KN/m2

Factored Load

= 1.57.325 =10.98 KN/m2

Taking 1.150m width of slab; load = 1.15010.98 =12.627 KN/m

For Loading :B
In a distance of 150mm from the wall and effective breadth of the section
increased by 75mm for purpose of design; there will be no live load in accordance
with code clues no: 33.2
Dead load of distance (150mm+75mm) =3.125 KN/m2
Floor Finish

=1.2 KN/m2

Total factor load= 1.5(3.125+1.2)1.150 = 7.46 KN/m

Design of stair flight
The entire loading on the flight is shown in above fig
Reaction at support B
RB3.35

= 12.6270.1250.125/2+17.562(0.125+1)+12.6271(0.125+2+1/2)
+7.460.225 (0.125+2+1+0.225/2)
47

=78.18
RB=23.337 KN
RA3.35= 7.460.2250.225/2+12.62710.725+17.5622.225+
12.6270.125 3.2875
=92.67
RA = 27.66 KN
Let, point of zero SF occurs at distance x from A.
27.6612.6270.12517.56(X-0.125) = 0
or,
Therefore,

X =1.60 m
Maximum BM occurs at X =1.60 m from A

Therefore,
Maximum BM = 27.661.60 12.627 0.125(1.60 0.125/2) 17.561.4751.475/2
=22.727KNm
Effective Depth of slab is given as;
BM = 0.138 ckbd2
d=

22.727 106 /( 0.138 20 1150)

d = 84.618 mm
Adopt effective depth as 110mm and overall depth as 125mm.

Calculation of Reinforcement:Area of tension steel is given as;

BM = 0.87yAst (d - 0.42 xm)
Or,

22.727106 = 0.87 415Ast (110 -

Ast 415
20 1150 )

Ast= 636.28mm2
Use 9_10mm bar equally spaced (=125) in 1.150m width
(Ast provided=706.8mm2) ok.
Check for Shear

48

Nominal Shear Stress v =

Vu
b*d

Percentage tensile Stress =

27.66 1000
1150 110
= 0.218 N/mm2

100 Ast
b*d

100 706.8
1150 110
=

= 0.56%

Shear Strength of M20 Concrete for 0.56% steel, (from Table 19)
Interpolating;
c = 0.50 N/mm2
Shear stress for slab

c = K c

Adopt,
K=1.3 for less than150mm thick slab
=1.3 0.50 = 0.65> v

Ok

Check for development Length for 10mm bar.

0.87 y

0.87 * 415
4 * (1.6 *1.2)

4 bd
Ld =

= 47 =4710 =470mm

From the point C as shown in fig. development length of 470mm should be available
in either direction to top as well as bottom bar.
Moment of resistance of 9_10mm bars
706
M1 =22.727 636

= 25.228 KN-m

V = 23.337KN

49

Let,

L0 = 0

Ld 1.3

M1
V

+L0
6

Or,

25.228 10
47 1.3 23.337 103
29.85mm

Since bar diameter provided is 10mm

Ok

Temperature reinforcement:
In the waist slab provide 0.12% steel as temperature reinforcement
=

0.12
2
100 1251000= 150 mm /m

Provide 8mm bar @ 330mm c/c spacing as shown in fig.

Design of Landing Slab A:

Effective Span =1.150+0.300+1.150+0.110 = 2.71m
Width = 1.150m

12.627 KN/m

17.56KN/m

12.63 KN/m

7.46KN/m

RB

RA
Fig: Loading on staircase

Factored load per m2 = 10.98 KN/m2

Therefore total load =10.981.1502.71 =34.22 KN
50

51

Reaction from one flight:

{17.5622.225+12.62710.725+7.460.2252/2}/3.35
= 26.12 KN
Reaction from two flights = 226.12 =52.24 KN
Maximum BM = wl2 /8 = (52.24+34.22)2.712/8 =79.39 KN m
Maximum SF = wl /2= (52.24+34.22)2.71/2=117.15 KN
Effective depth = 110mm
Calculation of reinforcement:
MOR of steel = 0.87fyAst(d-

fyAst
fckb )

Or, 79.39106 =0.87415Ast (110-415Ast/(201150)

Ast =1998.96 mm2
Provide area of steel is 2042mm2
Use 26-10mm bar at a distance 100mm c/c spacing.
Use temperature reinforcement as 0.12% of cross-section;
=0.121251000/100
=150 mm2/m@330mm c/c spacing.
Check For Shear:
Nominal shear stress (v ) = Vu/ bd
=117.151000/(1000110) =1.065 N/mm2
Percentage of steel (pt% ) =100Ast/bd
=1002042/(1000110)
=1.85%
Shear strength of concrete for 1.85% of steel is c =0.78
Shear strength for concrete slab: (c ) = c
=1.30.78
=1.014 N/mm2
Design shear stress (vs )= 1.065-1.014
=0.051 N/mm2
Use temperature reinforcement as shear reinforcement@0.12% of the section:
= 0.121000125/100
52

=150mm2 @330mm c/c spacing.

53

5.6 Designing a rainwater harvesting system

For the design of a rainwater harvesting system, rainfall data is required
preferably for a period of at least 10 years. The more reliable and specific the data is
for the location, the better the design will be. But we have taken data of the one years
only. Data for a given area was obtained at the Department of Hydrology amd
Meteorology Pokhara Ratna chowk.
Method of determining the required storage volume, and consequently the
size of the storage tank, is shown below:
Designing a Rainwater Harvesting System
Estimated Water Consumption = 20 l/c d
= 20 438
= 87,600 liters per year
= 87.6 m3 per year
= 7.3 m3 per year
= 7,300 liters per month
= 243.33 liters per day
Where water demand (d) = n 365 l/year

[ n = number of people ]

= 12 365
= 438
For dry period of four month,
Water demand = 7300 4 = 29200 liters
Amount of Rain water that can be collected = rainfall (mm/year) area run off
coefficient
Where,
-

Rainfall

(mm/

year)

(5.6+11.1+24.7+0+149.8+309.1+527
.1+803.7+580.4+115.4+3)

54

= 2529.9mm

Harvestable rainwater in calculated

area = slab area+slop area+ thatched
slab area
= 17,09,86,475 mm2

Run off coefficient for concrete

pavement, taken as 1
= 2529.9 170986475 mm3

= 2.5294 170.98 m3
= 432.57 m3 per year
= 36.04 m3 per month
Therefore volume of water collected ( V) = 36.04 m3 per month
= 1.2 m3 per month
= 1200 liters per day

55

Rainfall Data

Month

Jan.
Feb.
Mar.
Apr.
May.
Jun.
Jul.
Aug.
Sep.
Oct.
Nov.
Dec.
Total

Monthly Rainfall
(mm)

Harvestable

Rainwater in
calculated area (m3)

5.6
11.1
24.7
0
149.8
309.1
527.1
803.7
580.4
115.4
0
3
2529.9

Cumulative

Harvestable

0.975
1.897
4.22
0
25.61
52.64
90.12
137.41
99.23
19.73
0
0.51294
432.32

Rainwater in
calculated area (m3)
0.975
2.854
7.074
7.074
32.684
85.324
175.44
321.854
412.080
431.81
431.81
432.32
432.32

Volume of first flush and filter screen = 432.56 20%432.56

= 346.046 m3 per year
= 28.83 per month

Maximum rainwater collection = ( 36.04 28.83) = 7.2 m3 per month

So, volume of water to be collected is designed as 10 m3 per month
Let us adopt depth of rainwater tank = 4 m
56

Volume ( V )= BLd
10
4 = BL
2.5 = BL
Also,
L
B

2
1

L= 2B
We have ,
BL= 2.5
Or, 2B2 = 2.5
B= 1.1m

1.5 m

And ,
L = 2B = 21.5 = 3 m
Overall depth of tank = d + FB( Free Board)
= 4 + 0.5
= 4.5 m
Volume of designed tank (V) = BLD
= 1.534.5
= 20.25 m3
= 20,250 liters
Volume of water that can be collected (V1) = BLD
= 1.534
= 18 m3
= 18,000 liters
57

Graphical method to determine the required storage volume for a rainwater cistern

412.08431.81431.81432.32
cub-m

321.85

175.44
0.98 2.85 7.07 7.07

32.68

85.32

58

3
Figure 3 demonstrates the cumulative roof runoff (m ) over a one-year period and the
3
cumulative water demand (m ). The greatest distance between these two lines gives
3
the required storage volume (m ) to minimize the loss of rainwater.
Fig. 3: Graphical method to determine the required storage volume for a
rainwater cistern (adapted from Gould and Nissan-Petersen, 1999).

5.6.1 BASE FOR FLOOR SLAB

The floor slab should be strong enough to transmit the load from the liquid and the
structure itself to the ground without subsidence. The floor slab is usually 150 to 200
mm thick and is reinforced with nominal reinforcement, which may be provided in the
form of mesh both at top and bottom face of the slab. Before laying the slab the bed
has to be rammed and leveled then a 75 mm thick layer of lean concrete of M 100
grade should be laid and cured. This layer should be covered with tar to enable the
floor slab act independently on the bottom layer. In water logged soils the bottom
layer of concrete should preferably be of M 15 grade.
5.6.2 MINIMUM REINFORCEMENT FOR WATER TANK
Minimum reinforcement required for 199mm thick sections is 0.3 % of the area of
concrete section which reduced linearly to 0.2% for 450 mm thick sections. In case of
floor slab for tank resting on ground the minimum reinforcement from practical
consideration should not be less than 0.3% of the gross sectional area of the floor slab.
If the thickness of the section (wall, floor or roof slab of the tank) works out to be 225
mm and above two layers of reinforcing steel shall be placed, one near each of the
section to make up the minimum reinforcement requirements.

59

CHAPTER - 6
CONCLUSION
Structural analysis with reference to earthquake loads has been the main
objective of this report. The analysis is done using software program SAP 2000. The
project report is supplemented with loading drawings.
However, physical practice differs from design practice that was observed
during this project design period. For example the reinforcement design for structural
member beam has been changed for fabrication and placing convenience. Similarly
the general practice regarding some footing size under all columns also corrected in
footing design.
The feasibility of rainwater harvesting in a particular locality is highly
dependent on the amount and intensity of rainfall. As rainfall is usually unevenly
distributed throughout the year. Rainwater harvesting can usually serve as a
supplementary of household water. The demand of water may not be sufficient.

60

CHAPTER - 7
BIBLIOGRAPHY
1. Ashok K. Jain Reinforced Concrete, India: New chand& Bros, Civil lines, Roorkee
247 667,
2. SN Sinha Reinforced Concrete Design,New Delhi :Tata McGraw- Hill
3. Ramamrutha R. Narayan Reinforced Concrete Structure, Delhi-Jallandhar:
J.C.Kapur for DhanpotRai and Sons
4. SushilKunwar Treasure and R.C.C Design, India: S Chand & Ltd
5. S. Unnikerishna, Pillai& Devdas Menon Reinforced Concrete Design 3rd Edition,
India: Tata McGraw-Hill Education Pvt. Ltd
6. Design Aids for Reinforced Concrete to IS: 456-1978,Bahadurr Shah Zafarmarg,
New Delhi 110 002: Bureau of Indian Standard
7. Earthquake Resistance Design and construction of Building-Code of Practice
IS:4326-1993,ManakBhawan, Bahadur Shah ZafarMarg, New Delhi 110 002 :
Bureau of Indian Standards
8. Indian Standard Plain & Reinforced Concrete-Code of Practice, Bahadur Shah
ZafarMarg, New Delhi 110 002 : Bureau of Indian Standards
9. Structural Handbook, New Delhi, India: Bureau of Indian Standards
10. Water supply, BC Punima
11. Rainwater Harvesting, GUIDANCE TOWARD A SUSTAINABLE WATER
FUTURE, V1 | 3.6.2012
12. Rainwater Tank Design and Installation Handbook November 2008
13. Rainwater Harvesting by Norma Khoury- Nolde

61

ANNEX
Architectural Plan
Section and Elevation
Detailed Structure

62