Planning and Design of Engineering Systems

Graeme Dandy, David Walker, Trevor Daniell, Robert Warner, Bernadette Foley

• Publisher: CRC Press
• Year: 2017
• ISBN:
  9781351230674
• Edition: 3
• Topic: Technology & Engineering
• Subtopic: Civil Engineering
• Index: Technology & Engineering

This newly updated book offers a comprehensive introduction to the scope and nature of engineering work, taking a rigorous but common sense approach to the solution of engineering problems.

The text follows the planning, modelling and design phases of engineering projects through to implementation or construction, explaining the conceptual framework for undertaking projects, and then providing a range of techniques and tools for solutions. It focuses on engineering design and problem solving, but also involves economic, environmental, social and ethical considerations.

This third edition expands significantly on the economic evaluation of projects and also includes a new section on intractable problems and systems, involving a discussion of wicked problems and soft systems methodology as well as the approaches to software development. Further developments include an array of additional interest boxes, worked examples, problems and up-to date references.

Case studies and real-world examples are used to illustrate the role of the engineer and especially the methods employed in engineering practice. The examples are drawn particularly from the fields of civil and environmental engineering, but the approaches and techniques are more widely applicable to other branches of engineering.

The book is aimed at first-year engineering students, but contains material to suit more advanced undergraduates. It also functions as a professional handbook, covering some of the fundamentals of engineering planning and design in detail.

CHAPTER ONE

Engineering and Society

In this introductory chapter we discuss the nature, history, and scope of engineering work and the role of the engineer in society. In broad terms, engineers are responsible for designing, planning, constructing and maintaining the physical infrastructure that supports modern society and allows it to function effectively. Engineers make extensive use of scientific and mathematical knowledge, but their work is distinguished from the work of scientists and mathematicians by an emphasis on the use of all available relevant knowledge to solve real infrastructure problems as economically and efficiently as possible, in an environmentally and socially responsible way.

1.1 MODERN SOCIETY AND ITS ENGINEERED INFRASTRUCTURE

Modern society functions within the framework of a vast and complex engineered infrastructure that supports, and indeed makes possible, modern everyday life. For example, the large volumes of clean water that are used each day domestically, and by industry and agriculture, are supplied by a complex engineering system that is made up of remote rain catchment areas, reservoirs, pumping stations, pipelines, desalination plants, water treatment plants and local networks of reticulation pipes. The water supply system is one small part of the infrastructure. Another system generates and supplies the energy that is used to heat, cool and light the buildings that we live in, work in and relax in. Enormous amounts of additional energy are consumed by our factories and industries. Yet another part of the infrastructure enables communications over large distances and the sending and receiving of large quantities of information almost instantaneously. We use a transport system to move people and goods within and between our cities and urban regions and between countries. At home, at work and at leisure we have an array of low-cost manufactured goods available, including labour-saving devices, personal computers, smart phones and audio and TV devices that reduce our physical work load and entertain us. These are just a few examples of the component parts of the engineering infrastructure.

This engineering infrastructure is made up of large, separate, but interacting, parts, which we call “systems”. Each system has been designed to satisfy a specific set of goals that are related to community needs, and consists of many interacting components, or sub-systems. The built environment is a part of the engineering infrastructure. It consists of the many buildings, large and small, that provide shelter for us and for our belongings, and safe venues for our day-to-day activities. These buildings dominate the visual landscape of our cities and urban regions. They include high-rise and low-rise apartment buildings, houses, office buildings, factories, hospitals, schools, sports stadia, entertainment complexes and shopping complexes. They have been created by engineers, working with architects and builders. Of course, not all the engineering infrastructure is highly visible like the built infrastructure; much of it is unseen.

Although the engineering infrastructure has been created to satisfy community and individual needs, its functioning is not well understood or appreciated by many of the people who use it. When we want clean, fresh water we simply turn on a tap. We do not think about the many components and processes that bring the water to us. Likewise, by pulling the plug in a basin or by pressing a button on a toilet cistern we remove unwanted waste water and effluent without thinking of the complex disposal system and its many components that have been carefully planned, designed and constructed. Other disposal systems remove, treat and recycle the rubbish, garbage and other solid wastes that we generate. The processes of removal of liquid and solid wastes, of their transport, treatment, recycling and disposal, are out of sight and out of mind for most people. Lack of concern with, or understanding of, such details is perhaps a positive sign, that our engineering infrastructure is operating successfully.

This infrastructure has been developed progressively over many generations to meet the ongoing and expanding needs and demands of society, but there is also a feedback effect at play. The characteristics of the existing infrastructure, and especially its strengths and weaknesses, affect the way society itself develops and changes over time. A simple example is the way urban expansion is affected by the existing transport system. The transport system in a city develops in response to the need of the community to move people and goods efficiently, but there is inevitably a significant time delay before needed improvements are made to the existing transport corridors, and before new corridors can be constructed. New urban development therefore tends to cluster around the most efficient and most capacious existing transport corridors. The cost and efficiency of vertical construction and transport (in the form of fast elevators), as compared with the cost of land and horizontal transport, also influence the degree to which high-rise development will occur as well as, or as an alternative to, the continued outwards urban development.

In the past, major new steps forward in science and technology have resulted in enhancements to the infrastructure of our society. Over the last fifty or so years, developments have been particularly rapid, due in large part to the development of computer and Internet technologies. This development will continue into the foreseeable future and it will be complemented by the replacement of older parts of the infrastructure by newer and more efficient ones, because of the development of new, disruptive technologies.

It is the role of engineers to plan, design and create the systems, and their components, that constitute our physical infrastructure. They also have the task of managing, maintaining and expanding this infrastructure in response to developing societal needs.

Of course, the engineering infrastructure does not always operate perfectly, but for most of the time it is effective, efficient and economical. It is only on rare occasions, when for example there is a temporary interruption to the supply of water or electricity, or when the Internet is “down”, or when there are longer term water restrictions, that most people reflect on the engineering infrastructure that makes our modern life possible.

Unfortunately, there are many countries and regions in the world that are without adequate engineering infrastructure. This is a challenge to engineers, but it is an equal or even greater challenge to politicians and civil servants. There are always technical and organisational problems for engineers to solve, but poor infrastructure within a region or city or nation is usually indicative of broader issues and problems that do not have engineering solutions. It is too often a sign that fundamental social and political problems must be addressed by the people and their political representatives.

City growth and transport technology

In the past there has been a progressive increase in the size and population of cities around the world, which has resulted from the development of new transport technologies.

In ancient city states such as Athens, people relied on the muscle power of humans and animals for transport. Although heavy goods could be delivered using animal-drawn carriages, most citizens walked wherever they needed to go. The city size was thus limited by the ability of most people to walk to the various parts of their city, and home again, comfortably in a day. This limitation applied to ancient Rome, and to cities up to and beyond the middle ages.

It was not until the 17^th and 18^th Centuries that mass transport began, initially by means of large horse-drawn vehicles. Cities such as London and Paris then increased rapidly in size and population. Before this, the size and layout of a city were governed by the need for workers to be within walking distance of their places of work (Richards, 1969; White, 1978). With the invention of the steam engine and then the advent of city and suburban railways in the 19^th Century, large cities with a commuting workforce became possible.

In the 20^th Century, the internal combustion engine and the automobile, together with upgraded roads and freeways, allowed city conglomerates to develop with a very large population spread over an enormous urban area. The way of life in such cities is necessarily very different to that in a small traditional city, such as those still found in Europe.

In a discussion of the relative merits of compact cities, Gordon and Richardson (1997) state that in 1890 the effective radius of US cities was approximately 2 miles (3.2 km). By 1920 it had grown to 8 miles (12.9 km) following the development of public transport. By 1950 the figure had risen to 11 miles (17.7 km) with the widespread use of the automobile. By 1970, with the construction of urban freeways the average radius had increased to 20 to 24 miles (32.2 to 38.6 km).

1.2 HISTORICAL NOTE

In this short note, we can only provide a superficial view of engineering in history. However, society and its engineering infrastructure have developed together in step, and are closely interwoven. One practical lesson from history is that engineering work must be based on an understanding of society and how it functions, and on a careful and impartial evaluation of the sometimes-conflicting demands that come from individuals and from the community.

The first significant engineering works were probably undertaken around 10000 to 12000 years ago, when our human forebears started to live together in permanent settlements. This was a time of great change: humans were giving up the life of nomadic hunter-gatherers to adopt a more sedentary, agricultural-based way of life. The settlements needed basic infrastructure, such as permanent dwellings, all-weather pathways, and outer defensive walls to protect against wild animals and marauding humans. Archaeologists tell us that the agricultural revolution probably began in the river valleys of the Fertile Crescent in the Middle East, which includes parts of modern day Iraq, Turkey, Syria, Lebanon, Jordan, Israel, and Egypt.

This new communal way of life, based on agriculture and the domestication of animals, led to greater efficiency in the production of food, which in turn allowed the settlements to grow and to become more efficient. As the settlements grew, there was need for more complex infrastructure, for large, communal buildings and for permanent and reliable sources of water, both for domestic use and for agriculture. Archaeological evidence of early irrigation systems and large buildings abound in the Fertile Crescent. Ruins have been excavated in Turkey of monumental buildings that predate the Egyptian pyramids by millennia. Extensive engineering works were carried out by the Sumerians in present-day southern Iraq, in the period from the fifth to the second millennium BCE. According to Kramer (1963), the land they inhabited was “hot and dry, with soil that was arid and wind-swept and unproductive”. But by 3000 BCE the Sumerians had turned the land … “into a veritable Garden of Eden and developed what was probably the first high civilization in the history of man”. To transform their environment, they had to use both technological and organisational skills. As Kramer points out, “the construction of an intricate system of canals, dykes, weirs, and reservoirs demanded … engineering skill and knowledge. Surveys and plans had to be prepared which involved the use of levelling instruments, measuring rods, drawing, and mapping.” The creation of such buildings and irrigation canals required both the organisational and technological skills that are basic to engineering work.

Continuing improvements in the agricultural economy allowed people in larger settlements to specialise in their work, and, with increased leisure time, to put more effort into handicrafts and art forms. However, these developments also led to an ever more complicated way of life, and to a stratification of society with inequalities that are still with us. With everyday life and work becoming more and more complicated, it was necessary to create and maintain permanent records, and so the first systems of writing were developed, using the mediums of stone, wax, papyrus and, somewhat later, paper.

There was an increasing demand for engineering works as permanent settlements expanded into cities, supported by surrounding agricultural regions, and then as the cities and regions came together to become countries. Of course, these developments were not restricted to the Middle East. By the beginning of the common era, a little over 2000 years ago, the results of the agricultural revolution were to be seen in many parts of Europe, Asia and the Middle East. Engineering works of great complexity and magnitude had already been undertaken in ancient Egypt, the Roman Empire, India and China. Comparable developments in the Americas came somewhat later, because of the later migration of peoples into that part of the world.

The ever-increasing demands for an improved and expanded infrastructure led to increased efficiency and increased capacity in the irrigation systems for agriculture, the water supplies for cities, the roads for transport and for communication, and the walls and fortifications to protect cities against attack. In undertaking large, monumental engineering works, organisational skills were needed, as well as technological skills. As Rivers (2005) has pointed out, the Great Wall of China, which was started around the 6th or 7th Century BCE, “could not have been constructed solely with the technology of cutting stone from quarries and then transporting those stones to the designated sites. Unless an elaborate organisation existed in Chinese society, the Great Wall would never have been built, then or now.”

An ancient engineer’s life and its rewards

Sprague de Camp (1963) gives an account of an engineer who made good in ancient Egypt, a land of rigid class lines not easily crossed. However, engineers succeeded in crossing them, since engineering ability was not a common gift. The builder-engineer-architect Nekhebu (from 24^th Century BC) told on his tomb the story of his rise from humble beginnings:

“His Majesty found me a common builder; and His Majesty conferred upon me the offices of Inspector of Builders, then Overseer of Builders, and Superintendent of a Guild. And His Majesty conferred upon me the offices of King’s Architect and Builder, then Royal Architect and Builder under the King’s Supervision. And His Majesty conferred upon me the offices of Sole Companion, King’s Architect and Builder in the Two Houses.”

Nekhebu also received other titles and was rewarded with gold, bread and beer.

Early engineering was usually either military or non-military in nature. The term “civilian” engineering was used to distinguish between the two fields, and is now referred to as civil engineering. Armed conflict makes up a large part of human history; it seems that it has always been with us. Skirmishes surely occurred between small competing groups of hunter-gatherers. This would have escalated to conflict between permanent settlements, and out-and-out warfare between city stat...

Table of contents

• Cover
• Half Title
• Title Page
• Copyright Page
• Table of Contents
• PREFACE
• CHAPTER ONE ENGINEERING AND SOCIETY
• CHAPTER TWO ENGINEERING SYSTEMS CONCEPTS
• CHAPTER THREE ENGINEERING PLANNING AND DESIGN
• CHAPTER FOUR CREATIVITY AND CREATIVE THINKING
• CHAPTER FIVE PROJECT SCHEDULING TECHNIQUES
• CHAPTER SIX MANAGEMENT PROCESSES AND SKILLS
• CHAPTER SEVEN COMMUNICATION
• CHAPTER EIGHT ECONOMIC EVALUATION
• CHAPTER NINE SUSTAINABILITY, ENVIRONMENTAL AND SOCIAL CONSIDERATIONS
• CHAPTER TEN ETHICS AND LAW
• CHAPTER ELEVEN RISK AND RELIABILITY
• CHAPTER TWELVE ENGINEERING DECISION MAKING
• CHAPTER THIRTEEN OPTIMISATION
• CHAPTER FOURTEEN EPILOGUE