ACKNOWLEDGEMENT

First of all we would like to thank the Almighty God, ALLAH, who enables us to do this project.
Then it gives us great pleasure to express our deepest gratitude to our advisors Mr.V.S.Ravi
Kumar and Ato Kabtamu Getachaw. Their humble and continuous advice based on their
professional knowledge and experience, with much closely approach makes us very much
indebted to them.

We also would like to thank the project coordinator Ato Robel for finding us the architectural
plan of the building. Here it is also important to mention the collaboration of the head of
engineering and general service department for providing the architectural plan as requested by
the department.

Next our great fullness should go to Ato Jemal Jibril for his continuous advice from his
experience and knowledge, and also to Ato Mamuye Buser for giving us reading materials for
the project.

Finally, it is unforgettable for the support we received from our parents, relatives and friends.
Our special thanks go to the head and members of civil engineering department for they were
with us throughout the project time.
 OBJECTIVE
Final year project has a lot of aims (objectives) some of them are:

 To help the students in order to revised what have learnt in their time of study.

 To indicate for the students what qualifications should fulfilled to be a good engineer.

 It develops the habit of working together or in team.

 It introduces the real world designing processes and situation.

 INTRODUCTION
This project is structural design of G+ 4 offices and auditorium building with basement. The
building is curved in shape. It is located in Jimma University in front of the previous community
school. The plan area of the building is about 750m2 and the total height is 18.8m above the
reference level (0 levels).

The limit state design method is used for the entire structure. The Ethiopian building code of
standards (EBCS -1995) is solely used in the design with some books and lecture notes as a
reference. SAP 2000 version 9.0 computer software was used for all the analysis part of the
project.

For the design part, the output for each frame is obtained from different load combinations. For
foundation design the data for required parameters were assumed.
 ABSTRACT
This report consists of the structural design of a G+4 Office and auditorium building with a
basement. The function of the building is mainly for Office and auditorium. Contents of this
report have been divided into different chapters.

The first chapter deals with the structural planning. The positioning and orientation of columns,
positioning of beams and lay out of stairs are discussed in the chapter.

The major part of this report is chapter two, the analysis and design of roof and floor slabs.
Within this chapter the design of RCC water tank and the design of roof slabs from roof to the
ground floor is included. Due to the curved shape of the building the panels of each slab are
trapezoidal. Hence it requires modeling for analysis using EBCS-1995. They are changed to
equivalent rectangular form and the adequacy is checked by using yield line analysis method.
Detailed calculation and each step is shown during the roof slab design and for the rest the slabs,
we use excel design template which is developed by the Team itself. At the end of each slab
design the structural detail is done.

The design of staircase is included in the report. Six stairs, three at the middle and three at side
are designed. Like slabs, the details of all the six stairs are done.

The lateral loads from wind and earth quake are calculated. Since the earth quake load is the
governing load the frame analysis is done using the earth quake load.

Finally the design of beam, column, foundation and retaining wall with their structural details is
included in this project.
TABLE OF CONTENTS
CHAPTER ONE ..............................................................................................................................................
1. STRUCTURAL PLANING .............................................................................................................................
1.1 POSITIONING AND ORIENTATION OF COLUMNS ............................................................................................
1.2 POSITION OF BEAMS ......................................................................................................................................
1.3 LAYOUT OF STAIRS ..........................................................................................................................................
1.4 SPANING OF THE SLAB ....................................................................................................................................
1.5 SELECTING PROPER TYPES OF FOUNDATION..................................................................................................
CHAPTER TWO .............................................................................................................................................
2. ANALYSIS AND DESIGN OF ROOF SLAB .....................................................................................................
2.1. MODELING ...................................................................................................................................................
2.2 WIND LOAD ANALYSIS.....................................................................................................................................
2.3 DESIGN OF RCC WATER TANK .........................................................................................................................
2.3.1. DESIGN OF VERTICAL WALL OF WATER TANK ........................................................................................
2.3.2 DESIGN OF ROOF AND FLOOR SLAB OF WATER TANK .............................................................................
2.3.2 REINFORCEMENT FOR FLOOR AND ROOF SLAB AND VERTICAL WALL OF WATER TANK ........................
2.4 ROOF SLABS ....................................................................................................................................................
2.4.1 INTRODUCTION ........................................................................................................................................
2.5 ANALYSIS AND DESIGN OF 3RD AND 4TH FLOOR SLAB .............................................................................
2.5.1 INTRODUCTION ............................................................................................................................................
2.5.2 ANALYSIS AND DESIGN OF JOISTS ............................................................................................................
2.6 ANALYSIS AND DESIGN OF SECOND FLOOR SLAB ...........................................................................................
2.7. FIRST FLOOR SLAB ..........................................................................................................................................
2.8 GROUND FLOOR SLAB .....................................................................................................................................
2.9 BASEMENT FLOOR...........................................................................................................................................
CHAPTER THREE ...........................................................................................................................................
3.DESIGN OF STAIRCASE ...............................................................................................................................
3.1. SIDE STAIRCASE ..............................................................................................................................................
3.1.1 GROUND FLOOR STAIR.............................................................................................................................
3.1.2. TYPICAL FLOOR STAIR FOR SOLID SLAB...................................................................................................
3.1.3. TYPICAL FLOOR STAIR FOR RIBBED SLAB ................................................................................................
3.2. MIDDLE STAIRCASE ...................................................................................................................................
 3.2.1. GROUND FLOOR STAIR......................................................................................................................
3.2.2 TYPICAL FLOOR STAIR FOR SOLID SLAB....................................................................................................
3.2.3. TYPICAL FLOOR STAIR FOR RIBBED SLAB ................................................................................................
3.3 DESIGN OF RAMP ............................................................................................................................................
CHAPTER FOUR ............................................................................................................................................
4. LATERAL LOAD ANALYSIS ..........................................................................................................................
4.1.1 DETERMINATION OF SEISMIC LOAD ............................................................................................................
4.1.2. DETERMINATION OF CENTER OF MASS ......................................................................................................
4.1.2. Determination of center of stiffness .......................................................................................................
CHAPTER FIVE ..............................................................................................................................................
5. FRAME ANALYSIS .....................................................................................................................................
CHAPTER SIX ................................................................................................................................................
6. BEAM DESIGN ..........................................................................................................................................
CHAPTER SEVEN ...........................................................................................................................................
7. COLUMN DESIGN .....................................................................................................................................
CHAPTER EIGHT ...........................................................................................................................................
8. DESIGN OF FOUNDATION .................................................................................................................................
8.1 DESIGN OF ISOLATED FOOTINGS ....................................................................................................................
8.2 DESIGN OF COMBINED FOOTING....................................................................................................................
CHAPTER NINE .............................................................................................................................................
9.DESIGN OF RETAINING WALL .....................................................................................................................
CONCLUSION ...............................................................................................................................................
LIMITATION .................................................................................................................................................
RECOMMENDATION ....................................................................................................................................
REFERANCES ................................................................................................................................................
 GENERAL

CONCRETE:

i. Unit weight = 25KN/m2

ii. Concrete class = class 1 work,
iii. Grade = C-25
iv. Factor of safety γc = 1.50
v. Characteristics strength

fck = 0.8 * 25 = 20Mpa

fctk = 0.21*fck2/3 = 1.506Mpa

vi. Design strength

Fcd = 0.85fck/ γc = 11.33Mpa
Fctd = 0.21* fck2/3/1.5 = 1.031Mpa
M = fyd/ 0.8fcd = 28.78
C1 = 2.5/m = 0.0869
C2 = 0.32m2fcd = 3003
max = 0.6Ecu*fcd/(Ecu+Eyd)*fyd = 0.019

STEEL:

i. Grade = S-300
ii. Fyd = fyk/ γs = 260.87Mpa

DESIGN METHOD USED:

Limit state design