Civil Engineering Reference
In-Depth Information
Chapter 7
Key issues for multi-storey
buildings
John Roberts
Atkins, London, UK
doi: 10.1680/mosd.41448.0107
CONTENTS
7.1
Introduction
107
7.2
Managing the design
107
7.3
The building structure
as a system
112
7.4
Achieving the right
structure on plan
116
The success of multi-storey buildings must be judged across all design disciplines and be seen
through the client's and user's eyes. The structural engineer is a central member of a multi-
disciplinary team aiming to achieve the best answer to the brief. The design must develop
through an ordered series of stages, with appropriate options investigated, discussed, discarded
or adopted. Excellent communication is the key to shared understanding across the team.
7.5
Achieving the right
structural section
117
7.6
Accommodating other
components and issues
121
7.7
Tall buildings
124
7.8
Summary
126
Once the appropriate loads have been defined the building's structure should carry these to the
ground in a clear and straightforward way. The appropriate materials and structural form need
to be investigated and selected. On plan movement joints and stability systems are positioned,
and the columns laid out. The interrelationship of the different uses within the building must
be understood, the most direct vertical load paths through these being strongly preferred,
with any required transfer structures identified early in the design process. Within each floor
zone structure, services and architecture should be coordinated within the optimal depths. The
engineer will also have input into 'non-structural' issues including partitions and cladding, fire
and corrosion, plant and stairs, contributing to the success of the building as a whole.
7.9
Conclusions
126
7.10 Note
126
7.11 References
126
structure must work with 'non-structural' requirements and
Section 7.7 looks at how all these issues develop and drive our
design as we strive to build higher.
So when is a building 'multi-storey'?
Accommodation on just the ground floor with just a roof
and walls evidently isn't and anything more than that prob-
ably is. However, as more floors are added the vertical circu-
lation (stairs, lifts, escalators), service risers and horizontal
stability structures begin to increase in importance for the
design, and their impact on the relationship of the various
building functions increasingly needs to be coordinated in
three dimensions.
The building will be supported by a foundation and may sit
over a basement structure. The configuration and movement of
these may well influence the superstructure above. However,
discussion of these is beyond the limits of this chapter.
7.1 Introduction
A multi-storey building is much more than just a multi-storey
structure. It is a complex three-dimensional object with many
components, all contributing to its users' perception of its
success - architecture, building services, structure and fit-out.
Through its lifetime, which may be longer than planned, it
may evolve or even completely change in function. It requires
resources to put it together and will continue to consume these
throughout its life. It may be a blot on the landscape or bring
joy to the world.
Within this present and future complexity the engineer
needs to deliver a structural design that is efficient, safe, fulfils
the structural brief and enables all the other building elements
to perform as required. To achieve this wider definition of suc-
cess the structural engineer must proactively work as part of a
multi-disciplinary team achieving the client's needs.
This chapter starts with 'Managing the design' (Section 7.2).
Achieving a successful building requires a team to go through
a design life-cycle of ordered steps of analysis and decisions.
Throughout this time they need to test their proposals against
the client's brief, understand the needs of the other disciplines
and communicate the implications of their chosen structure.
Section 7.3 discusses how the structure works within the
building as a whole and the requirements the choice of struc-
ture must be tested against. The advantages and disadvantages
of some common structural systems are discussed. Section 7.4
discusses key considerations when choosing the layout of col-
umns, cores and movement joints. Section 7.5 looks at issues
that drive the design through the height of the building, both
overall and floor by floor. Section 7.6 discusses the way the
7.2 Managing the design
7.2.1 The design life-cycle
In order to deliver the optimal design of building when judged
against cost, quality, time or environmental impact, it is
important that the design team proceeds in an orderly series of
steps: the design life-cycle. First they need to understand the
brief, investigate and evaluate the available options and then
make the best choices. After that the information for costing,
tender and construction needs to be developed.
Terminology around the world varies but the work of all
building design teams should go through a series of generic
stages. The exact balance of work carried out and the split of
deliverables between the stages varies slightly across projects,
