CIVL4903/9903 ASSIGNMENT 1 Floor Systems

CIVL4903/9903 ASSIGNMENT 1
Floor Systems




By

Group 8
Kim Hien Le 440506838
Mufaro Ambrose Tumbare 430027060
Pik Wei Chng 450024890
Yisu Chen 460338299
Weichi Zhu 440077394


School of Civil Engineering

University of Sydney, NSW 2006 Australia

28 August 2017


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, TABLE OF CONTENTS
TYPICAL OFFICE FLOOR ....................................................................................................... 4

PART I – SCHEMATIC DESIGN AND PRESTRESSING ..................................................... 4
INTRODUCTION ...................................................................................................................... 4
1. COLUMN LAYOUT .............................................................................................................. 4
1.1. Schematic Diagrams of Two Main Options for Column Layout ..................................... 4
1.2. Likely Advantages and Disadvantages of Each Grid Option .......................................... 4
2. PRETRESSED BEAM AND ONE WAY SLAB – SCHEMATIC DESIGN OF BEAM AND
SLAB SIZE ................................................................................................................................. 6
2.1. Initial Beam and Slab Depth Calcuations ....................................................................... 6
2.1.1. Option 1 .................................................................................................................... 7
2.1.2. Option 2 .................................................................................................................... 7
2.2. Member Sizes in a Typical Bay Schematic Diagrams ..................................................... 7
2.3. Comparable Designs........................................................................................................ 7
2.3.1. Option 1 .................................................................................................................... 7
2.3.2. Option 2 .................................................................................................................... 7
3. CONCEPTUAL DESIGN OF THE AMOUNT OF PRESTRESS FOR TYPICAL SPANS .. 8
3.1. Total self-weight dead load (slab + beam) carried by an individual band beam ........... 8
3.2. AMOUNT OF PRE-STRESS FORCE ‘T’ REQUIRED ..................................................................... 8
3.3. NUMBER OF STRANDS REQUIRED ........................................................................................... 8
4. STRENGTH CALCULATIONS ............................................................................................ 8
5. COST ESTIMATES .............................................................................................................. 14
5.1. Option 1: ........................................................................................................................ 14
5.2. Option 2: ........................................................................................................................ 16

PART II – COMPOSITE STEEL ............................................................................................. 17
6. STEELWORK FLOOR DESIGN ......................................................................................... 17
6.1. Schematic Diagrams ...................................................................................................... 17
6.2. Beam Size Approximations ............................................................................................ 17
6.2.1. Option 1 .................................................................................................................. 17
6.2.1.1. TABULATED METHOD: .................................................................................................... 17
6.2.1.2. STRENGTH APPROXIMATION METHOD 1: ......................................................................... 20
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,6.2.1.3. STRENGTH APPROXIMATION METHOD 2: ......................................................................... 21
6.2.1.4. STRENGTH APPROXIMATION METHOD 3 – SPAN/DEPTH RATIO: ....................................... 22
6.2.2. Option 2 .................................................................................................................. 22
6.2.2.1. TABULATED METHOD: .................................................................................................... 22
6.2.2.2. STRENGTH APPROXIMATION METHOD 1: ......................................................................... 22
6.2.2.3. STRENGTH APPROXIMATION METHOD 1: ......................................................................... 23
6.2.2.4. STRENGTH APPROXIMATION METHOD 3 – SPAN/DEPTH RATIO: ....................................... 24
6.3. Beam Size Summary ....................................................................................................... 25
6.4. Cost Estimations ............................................................................................................ 25
6.4.1. Option 1 .................................................................................................................. 25
6.4.2. Option 2 .................................................................................................................. 26
7. PROVISION FOR BUILDING SERVICES ......................................................................... 27
8. CONCLUSION - P/T CONCRETE VS COMPOSITE STEEL DESIGNS .......................... 36
REFERENCES ......................................................................................................................... 40




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, TYPICAL OFFICE FLOOR
PART I – SCHEMATIC DESIGN AND PRESTRESSING
INTRODUCTION
This report covers the preliminary design process for a typical office floor, considering two
alternative options: post-tension (P/T) concrete and composite steel. Each design option will be
weighed on cost and constructability through thorough calculations and cost benefit analysis, so
the superior design can be recommended.


1. COLUMN LAYOUT
The floor system requires a best suited column layout that will achieve a good balance between
flexible open space, structural depth and economy. There are two column layouts to be
considered:
•! Option 1: Two internal columns per bay spaced at 15m with a cantilever zone at each
end and no perimeter columns.
•! Option 2: One internal column and two perimeter columns per bay to creat two 12m
spans, allowing or columns.


1.1. Schematic Diagrams of Two Main Options for Column Layout
See Appendix I


1.2. Likely Advantages and Disadvantages of Each Grid Option


Option 1 Option 2
•! There are less columns per bay (2 •! Ease of construction as the floor
columns compared to 3 columns system is simply supported.
in option 2). Assuming each •! Having only 1 row of internal
Advantages 900mm column can adequately column means obstruction to the
support the design load, design office open space is limited
option 1 saves one column worth •! Option 2 has two 12m span in the
of materials per bay. N/S direction, hence offers more



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