全新工程系统规划与设计指南第三版：严谨解决实践问题

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Engineering and Society 3

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

and 18

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

Century, large cities with a

commuting workforce became possible.

In the 20

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.

Engineering and Society 4

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.

Engineering and Society 5

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

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

states, and then between countries and even civilisations.

Two important aspects of military engineering are defence and attack. The

engineering works used in the defence of ancient cities included high outer walls

and fortifications, and large underground cisterns within the city to store water. To

attack and besiege a city, military engineers could attempt to undermine the outer

walls and fortifications, and use mechanical catapults to bombard the walls and the

interior of the city with large rocks. Movable towered structures with protective

armour assisted in the breaching of walls. Catapults and cranes were used by the

defenders to bombard the attacking army and to drop rocks and burning oil on those

attempting to scale the walls. There were also non-engineering options for the

besieging army: to attempt to poison the water supply and to cut off the supply lines

to the city that brought food and other essential goods.

Engineering and Society 6

Early American civilisations and their engineering infrastructure

When Juan de Grijalva set sail from Havana on April 8, 1518, he was in search of

an ancient civilisation, one that Spanish sailors had discovered quite by accident

the previous year. Three sailing ships, blown off course by a severe storm, had

happened upon ancient ruins of a splendid city. There, according to Gallenkamp

(1960) “an astonishing sight was visible in the distance: rising up as though an

outgrowth of the native limestone were a high wall enclosing a series of terraced

pyramids and palace-like buildings constructed of carefully fitted stones”.

The constructions were more than just the work of skilled stonemasons: they

showed a high level of planning, design and organization, and the Spaniards were

convinced they had found a lost civilisation. This assessment came well before they

saw any of its population, before they had studied its language, its art, and its legal

and political systems. The evidence of technological expertise, engineering skill

and organisation on a significant scale was all that was required.

The Maya civilisation was not unique. There were also the Incas in South

America and the Aztecs in central and southern Mexico. In each case an advanced

civilisation could be recognised by the architecture and engineering infrastructure.

On further study, the characteristics of each civilisation were uncovered.

Sometimes there were surprises: the Incas had no written language, nor had they

developed the wheel, yet the fact that they had achieved a state of civilisation was

beyond question on the basis of their engineering prowess alone.

Figure 1.1 Ruins of the Inca Settlement at Machu Picchu, constructed in the mid-15

Century CE

Archaeological evidence indicates that mechanical, mining and chemical

engineering works were also undertaken in the distant past, when humans started to

live together in settlements. Around 9800 BCE, gypsum plaster was produced in

Engineering and Society 7

Mesopotamia by heating gypsum in wood-fired kilns. This material is also known

as “plaster of Paris” because there was a large deposit of gypsum in Montmartre in

Paris, France. In the time between 8000 and 7000 BCE, people inhabiting what

is now modern day Turkey mined copper ore. They beat it into beads, hooks and

metal sheets. Somewhat earlier, the people of Mesopotamia had formed copper

plates into small tubes as a form of jewellery (Mithen, 2003).

Later in ancient Rome, multi-storey apartment buildings up to six stories high

were constructed in the cheap parts of town to house the ordinary people, the

plebeians. As the building work was often shoddy, special building ordinances were

created to try to improve the quality of construction.

Water was supplied to the city of Rome (though not to individual apartment

buildings) by aqueducts. These traversed the plains, and, where necessary, linked up

with tunnels that were dug through the hills. Of the 11 aqueducts for the city of

Rome, one was over 100 km in length. In the city, water was reticulated by means

of pipes made of clay and lead. Although engineering has been attributed with

improving the health of populations by the provision of clean potable (drinkable)

water, it has been speculated that the use of lead water pipes may have been

responsible for lead poisoning among the population of Rome before its fall in the

5th Century CE.

Spectacular multi-level stone Roman aqueducts still survive in various places

in Europe, such as Segovia in Spain, and Nîmes in France (Figure 1.2).

Figure 1.2 The Roman Pont du Gard, part of the Nîmes aqueduct crossing the Gardon river in

Engineering in the ancient world was based on experience and empirical rules.

According to Straub (1952) “Despite the remarkable scientific standard, especially

of the Greeks in the spheres of mechanics and statics, there was hardly any

connection between theory and practice, and hardly any attempt to apply the

scientific knowledge to practical purposes, in the sense of modern engineering.”

Engineering was practised as a craft, with reliance on common sense and time-

honoured experience rather than on the application of scientific principles.

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