Standard-Handbook-for-Civil-Engineers, Building and Architecture

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Table of Contents
Contributors
Preface
About the Editors
Sect. 1 Systems Design
Sect. 2 Design Management
Sect. 3 Specifications
Sect. 4 Construction Management
Sect. 5 Construction Materials
Sect. 6 Structural Theory
Sect. 7 Geotechnical Engineering
Sect. 8 Concrete Design and Construction
Sect. 9 Structural Steel Design and Construction
Sect. 10 Cold-Formed-Steel Design and Construction
Sect. 11 Wood Design and Construction
Sect. 12 Surveying
Sect. 13 Earthwork
Sect. 14 Community and Regional Planning
Sect. 15 Building Engineering
Sect. 16 Highway Engineering
Sect. 17 Bridge Engineering
Sect. 18 Airport Engineering
Sect. 19 Rail-Transportation Engineering
Sect. 20 Tunnel Engineering
Sect. 21 Water Resources Engineering
Sect. 22 Environmental Engineering
Sect. 23 Coastal and Port Engineering
App Factors for Conversion to the Metric System (SI) of Units
Index
1
Source: Standard Handbook for Civil Engineers
Jonathan T. Ricketts*
Consulting Engineer
Palm Beach Gardens, Florida
S
YSTEMS
D
ESIGN
neering concerned with planning,
design and construction of natural
resource development, regional and
local water supply and stormwater facilities, waste
management facilities, transportation facilities, tun-
nels, buildings, bridges, and other structures for
the needs of people. Persons who are qualified by
education and experience and who meet state
requirements for practicing the profession of civil
engineering are called civil engineers.
5. Perform services only in areas of competence; in
other areas, engineers may engage or collabo-
rate with qualified associates, consultants, or
employees for performing assignments.
Accordingly, civil engineering projects should be
planned, designed, and constructed to satisfy the
following criteria:
1. They should serve the purposes specified by the
owner or client.
2. They should be constructable by known tech-
niques and with available labor and equipment
within a time acceptable to the owner or client.
3. They should be capable of withstanding the
elements and normal usage for a reasonable
period of time.
4. Projects when completed should be optimum—
lowest cost for the purposes intended or the best
for the money spent—as required by the owner
or client. Construction cost should not exceed
the client’s construction budget, and operation,
maintenance, and repair, when properly exe-
cuted, should not be excessively costly.
1.1 Performance Criteria for
Civil Engineers
As professionals, civil engineers should conform to
the following canons as they perform their duties:
1. Hold paramount the safety, health, and welfare
of the public. (Welfare of the public implies a
commitment to sustainable development which
is meeting the current needs and goals of the
project while protecting the natural resource
base for future generations.)
2. Act for every employer or client as faithful
agents or trustees and avoid conflict of interest.
3. Apply to the fullest extent their knowledge and
skill to every client’s project.
4. Maintain life-long learning, always willing to
participate in the professional exchange of ideas
and technical information.
5.
Projects should be designed and constructed to
meet pertinent legal requirements, conform
with generally accepted engineering standards,
and avoid endangering the health and safety of
construction workers, operators of the projects,
and the general public.
6.
Projects should be designed to meet the goals of
sustainable development which are meeting
project needs while conserving and protecting
environmental quality and the natural resource
base for future generations.
*Revised and updated from “System Design” by Frederick
S. Merritt.
1.1
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C
ivil engineering is that field of engi-
SYSTEMS DESIGN
1.2
n
Section One
7. Projects, when properly operated, should be
energy efficient.
8. To the extent possible, projects should display
aesthetic qualities.
For a project to be treated as a system, as required
in systems design, it is necessary to know what a
system is and what its basic characteristics are:
A system is an assemblage formed to satisfy specific
objectives and subject to constraints or restrictions and
consisting of two or more components that are inter-
related and compatible, each component being essential
to the required performance of the system.
Because the components are required to be
interrelated, the operation, or even the mere
existence, of one component affects in some way
the performance of other components. Also, the
required performance of the system as a whole and
the constraints on the system impose restrictions on
each component.
Examples of civil engineering systems include
buildings, highways, bridges, airports, railroads,
tunnels, water supply to meet human needs, and
wastewater collection, treatment, and disposal.
A building is a system because it is an as-
semblage constructed to serve specific purposes,
such as shelter for human activities or enclosure of
stored materials. It is subject to such restrictions as
building code limitations on height and floor area.
Constraints include ability to withstand loads from
human activities and from natural forces like wind
and earthquakes. The assemblage generally con-
sists of a roof, floors, walls, doors, windows,
structural framing for supporting the other com-
ponents, and means for heating, ventilating, and
cooling the interior.
A highway or a railroad is a system constructed
for the specific purpose of providing a suitable
surface, or road, for movement of vehicles.
The restrictions are imposed by the terrain to be
traversed by the highway or railroad, vehicle
characteristics, and volume of traffic. A highway is
used primarily by rubber-tired vehicles whose
velocity and direction of travel are controlled by
human drivers. A railroad is used by vehicles
equipped with steel wheels designed to ride on
rails that control direction of travel, while velocity is
controlled directly by a human driver or indirectly
by remote controls. Both highway and railroad
assemblages consist of a right-of-way and road
between points to be served, entrances and exits for
vehicles, traffic-control devices, safety devices,
bridges, tunnels, stations for refueling and
servicing vehicles, stations for embarking or
disembarking passengers or loading or unloading
freight, and convenience stations for drivers and
passengers.
The ultimate objective of design is to provide, in
precise, concise, easy-to-comprehend form, all the
information necessary for construction of the
project. Traditionally, designers provide this infor-
mation in drawings or plans that show what is to
be constructed and in specifications that describe
materials and equipment to be incorporated into
the project. Designers usually also prepare, with
legal assistance, a construction contract between
the client and a general contractor or two or more
prime contractors. In addition, designers generally
observe or inspect construction of the project. This
should be done not only to help the client ensure
that the project is constructed in accordance with
plans and specifications but to obtain information
that will be useful for designing future projects.
1.2 Systems
Systems design of a project comprises a rational,
orderly series of steps that leads to the best decision
for a given set of conditions (Art. 1.9). The pro-
cedure requires:
Analysis of a project as a system
Synthesis, or selection of components to form a
system that meets specific objectives
Appraisal of system performance, including com-
parisons with alternative systems
Feedback to analysis and synthesis of information
obtained in system evaluation, to improve the
design
The prime advantage of the procedure is that,
through comparisons of alternatives and data
feedback to the design process, system design
converges on an optimum, or best, system for the
given conditions. Another advantage is that the
procedure enables designers to clarify the require-
ments for the project being designed. Still another
advantage is that the procedure provides a
common basis of understanding and promotes
cooperation between the specialists in various
aspects of project design.
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SYSTEMS DESIGN
Systems Design
n
1.3
A tunnel is an underground system and a
bridge is an aboveground system constructed for
the specific purpose of providing passage for
pedestrians, vehicles, pipes, cables, or conveyors
past obstructions. A tunnel is subject to such
restrictions as exclusion of earth, rock, and
unwanted water from the passageway, whereas a
bridge must carry the passageway at required
distances above obstructions. A tunnel assemblage
consists primarily of the passageway and supports
or lining for housing the passageway. The
assemblage may also include drainage, ventilation,
and lighting provisions. A bridge assemblage
consists primarily of the passageway, structural
framing for supporting it, and piers and abutments
for holding the other components at suitable
heights above the obstructions.
Water supply is a system with the specific
purpose of providing water to meet human needs.
The restrictions on the system are generally criteria
for quantity and quality of water. The assemblage
usually consists of a water source; means for
extracting water in desired quantities from the
source and conveying it to points where it is needed;
a plant for treating the water to meet quality criteria;
pipes with diameters adequate for passing the
desired quantities without excessive loss of pres-
sure; valves; reservoirs; dams; and fixtures and other
devices for flow control at points of use.
Sewage collection, treatment, and disposal is a
system with the specific purpose of removing
wastewater from points where it is created and
discharging the wastes in such condition and in
such locations that human health and welfare are
not endangered and there is little or no adverse
effect on the environment. The restrictions on
the system generally are quantity and character-
istics of the wastes, quantity of water needed for
conveyance of the wastes, and criteria for the
products to be discharged from the system. The
assemblage consists of fixtures or other means for
collecting wastes at the source and removing them
with water; means for conveying the wastewater to
a treatment plant and then transporting the treated
products to points of disposal or reuse; the
treatment plant where the wastes are removed or
rendered innocuous; means for safe disposal or
reuse of the treated wastes and water; pipes;
valves; and various devices for flow control.
Note that in all the preceding examples the
system consists of two or more interrelated,
compatible components. Every component is
essential to the required performance of the
system. Also, every component affects the per-
formance of at least one other component, and the
required performance of the whole system imposes
restrictions on every component.
Subsystems
n
A group of components of a
system may also be a system called a subsystem. It
too may be designed as a system, but its goal must
be to assist the system of which it is a component to
meet the system objectives. Similarly, a group of
components of a subsystem may also be a system
called a subsubsystem.
For brevity, a project’s major subsystems often
are referred to as systems. For example, in a
building, such major subsystems as structural
framing, walls, or plumbing are called systems.
Their components that meet the definition of a
system are referred to as subsystems. For instance,
plumbing consists of water-supply, wastewater,
and gas-supply subsystems. The wastewater sub-
system in turn includes various fixtures for col-
lecting and discharging wastewater; soil and waste
pipes; pipe supports; traps; drains; sewers; and
vents. In a complex system, such as a building,
subsystems and other components may be com-
bined in various ways to form different systems.
1.3 Systems Analysis
In systems analysis, a system is resolved into its
basic components. Subsystems are determined,
and then the system is investigated to determine
the nature, interaction, and performance of the
system as a whole. The investigation should
answer such questions as:
What does each component (or subsystem) do?
What does the component do it to?
How does the component serve its function?
What else does the component do?
Why does the component do the things it does?
What must the component really do?
Can the component be eliminated because it is not
essential or because another component can
assume its tasks?
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