Unit -1

Introduction to Course and Overview

Q1) What is civil engineering?

A1)

Civil engineering is a professional engineering discipline that deals with the design, construction and maintenance of the physical and naturally built environment including public works such as roads, bridges, canals, dams, airports, sewerage systems, pipelines, structural components of buildings and railways.

Civil engineering is traditionally broken into a number of sub-disciplines. It is considered the second oldest engineering discipline after military engineering and it is defined to distinguish non military engineering from military engineering. Civil engineering takes place in the public sector from municipal through to national governments, and in the private sector from individual homeowners through to international companies.

 Civil Engineering involves planning, designing, constructing, maintaining and supervising infrastructures which include facilities essential to modern life like highways, bridges and tunnels, schools, hospitals, airports and other buildings, sewage systems and water treatment facilities.

Q2) What were the attributes of pre industrial society?

A2)

The attributes of pre industrial society were

Q3) How did the industrial revolution change society and economies?

 A3)

The Industrial Revolution increased the overall amount of wealth and distributed it more widely than had been the case in earlier centuries, helping to enlarge the middle class. However, the replacement of the domestic system of industrial production, in which independent crafts-persons worked in or near their homes, with the factory system and mass production consigned large numbers of people, including women and children, to long hours of tedious and often dangerous work at subsistence wages. Their miserable conditions gave rise to the trade union movement in the mid-19th century.

The Industrial Revolution transformed economies that had been based on agriculture and handicrafts into economies based on large-scale industry, mechanized manufacturing, and the factory system. New machines, new power sources, and new ways of organizing work made existing industries more productive and efficient. New industries also arose, including, in the late 19th century, the automobile industry.

Q4) What were some important inventions of the industrial revolution?

 A4)

1. Spinning and weaving

The creation of the following ingenious machines made possible the mass production of high-quality cotton and woollen thread and yarn and helped transform Great Britain into the world’s leading manufacturer of textiles in the second half of the 18th century.

The spinning jenny: About 1764 James Hargreaves, a poor uneducated spinner and weaver living in Lancashire, England, conceived a new kind of spinning machine that would draw thread from eight spindles simultaneously instead of just one, as in the traditional spinning wheel. He obtained a patent for the spinning jenny in 1770.

The water frame: So called because it was powered by a waterwheel, the water frame, patented in 1769 by Richard Arkwright, was the first fully automatic and continuously operating spinning machine. It produced stronger and greater quantities of thread than the spinning jenny did.

The spinning mule: About 1779 Samuel Crompton invented the spinning mule, which he designed by combining features of the spinning jenny and the water frame. His machine was capable of producing fine as well as coarse yarn and made it possible for a single operator to work more than 1,000 spindles simultaneously.

2. The steam engine

Steamboats and steamships:  The first commercially successful paddle steamer, the North River Steamboat, designed by American engineer Robert Fulton, travelled up the Hudson River from New York City to Albany, New York, in 1807 at a speed of about 5 miles (8 km) per hour.

3. Harnessing electricity

In the early 19th century, scientists in Europe and the United States explored the relationship between electricity and magnetism, and their research soon led to practical applications of electromagnetic phenomena.

Electric generators and electric motors:  The first phenomenon eventually became the basis of the electric motor, which converts electrical energy into mechanical energy, while the second eventually became the basis of the electric generator, or dynamo, which converts mechanical energy into electrical energy.

Electric railways and tramways: The first electric railway, intended for use in urban mass transit, was demonstrated by German engineer Werner von Siemens in Berlin in 1879. By the early 20th century, electric railways were operating within and between several major cities in Europe and the United States. The first electrified section of London’s subway system, called the London Underground, began operation in 1890.

The incandescent lamp: In 1878–79 Joseph Wilson Swan in England and later Thomas Alva Edison in the United States independently invented a practical electric incandescent lamp, which produces continuous light by heating a filament with an electric current in a vacuum (or near vacuum).

4. The telegraph and the telephone

Two inventions of the 19th century, the electric telegraph and the electric telephone, made reliable instantaneous communication over great distances possible for the first time their effects on commerce, diplomacy, military operations, journalism, and myriad aspects of everyday life were nearly immediate and proved to be long-lasting.

5. The internal-combustion engine and the automobile

Among the most-consequential inventions of the late Industrial Revolution were the internal-combustion engine and, along with it, the gasoline-powered automobile. The automobile, which replaced the horse and carriage in Europe and the United States, offered greater freedom of travel for ordinary people, facilitated commercial links between urban and rural areas, influenced urban planning and the growth of large cities, and contributed to severe air-pollution problems in urban areas.

Q5) What was the second industrial revolution?

 A5)

Despite considerable overlapping with the “old,” there was mounting evidence for a “new” Industrial Revolution in the late 19th and 20th centuries. In terms of basic materials, modern industry began to exploit many natural and synthetic resources not hitherto utilized: lighter metals, new alloys, and synthetic products such as plastics, as well as new energy sources. Combined with these were developments in machines, tools, and computers that gave rise to the automatic factory. Although some segments of industry were almost completely mechanized in the early to mid-19th century, automatic operation, as distinct from the assembly line, first achieved major significance in the second half of the 20th century

Ownership of the means of production also underwent changes. The oligarchical ownership of the means of production that characterized the Industrial Revolution in the early to mid-19th century gave way to a wider distribution of ownership through purchase of common stocks by individuals and by institutions such as insurance companies. In the first half of the 20th century, many countries of Europe socialized basic sectors of their economies. There was also during that period a change in political theories: instead of the laissez-faire ideas that dominated the economic and social thought of the classical Industrial Revolution, governments generally moved into the social and economic realm to meet the needs of their more complex industrial societies. That trend was reversed in the United States and the United Kingdom beginning in the 1980s.

Q6) What are the major civil engineering innovations?

A6)

New materials and energy, design approaches, as well as advances in digital technology and big data, are creating a wave of innovation within the construction industry. Here are ten of the most exciting developments

1. Self-healing concrete

Cement is one of the most widely used materials in construction, but also one of the largest contributors to harmful carbon emissions, said to be responsible for around 7 per cent of annual global emissions. Cracking is a major problem in construction, usually caused by exposure to water and chemicals. Researchers at Bath University are looking to develop a self-healing concrete, using a mix containing bacteria within microcapsules, which will aid building innovation by germinating when water enters a crack in the concrete to produce limestone, plugging the crack before water and oxygen has a chance to corrode the steel reinforcement.

2. Thermal bridging

Efficient insulation material is becoming increasingly important throughout the construction industry. Heat transmission through walls tends to be passed directly through the building envelope, be it masonry, block or stud frame, to the internal fascia such as drywall. This process is known as “thermal bridging”. Aerogel, a technology developed by Nasa for cryogenic insulation, is considered one of the most effective thermal insulation materials and US spin-off Thermablok has adapted it using a proprietary aerogel in a fibreglass matrix.  This can be used to insulate studs, which can reportedly increase overall wall R-value (an industry measure of thermal resistance) by more than 40 per cent.

3. Photovoltaic glaze

One of the most exciting new technologies used in civil engineering is building integrated photovoltaic (BIPV) glazing, which can help buildings generate their own electricity, by turning the whole building envelope into a solar panel. Companies such as Polysolar provide transparent photovoltaic glass as a structural building material, forming windows, façades and roofs. Polysolar’s technology is efficient at producing energy even on north-facing, vertical walls and its high performance at raised temperatures means it can be double glazed or insulated directly. As well as saving on energy bills and earning feed-in tariff revenues, its cost is only marginal over traditional glass, since construction and framework costs remain, while cladding and shading system costs are replaced.

4. Kinetic Footfall

One of the latest civil engineering technologies under development is kinetic energy. Pavegen provides a technology that enables flooring to harness the energy of footsteps. It can be used indoors or outdoors in high traffic areas, and generates electricity from pedestrian footfall using an electromagnetic induction process and flywheel energy storage. The technology is best suited to transport hubs where a large flow of people will pass over it. The largest deployment the company has done so far is in a football pitch in Rio de Janeiro to help power the floodlights around the pitch. It also currently has a temporary installation outside London’s Canary Wharf station powering street lights.

5. Kinetic Roads

Italian startup Underground Power is exploring the potential of kinetic energy in roadways. It has developed a technology called Lybra, a tyre-like rubber paving that converts the kinetic energy produced by moving vehicles into electrical energy. Developed in co-operation with the Polytechnic University of Milan, Lybra operates on the principle that a braking car dissipates kinetic energy. The cutting-edge technology is able to collect and convert this energy into electricity before passing it on to the electricity grid. In addition to improving road safety, the device upgrades and promotes sustainability of road traffic.

6. Predictive Software

The structural integrity of any building is only as good as its individual parts. The way those parts fit together, along with the choice of materials and its specific site, all contribute to how the building will perform under normal, or extreme, conditions. Civil engineers need to integrate a vast number of pieces into building designs, while complying with increasingly demanding safety and government regulations. Predictive software can help ensure even the most innovative structures in civil engineering are safe and efficient, by simulating how they will behave. An example of this was work on the structural integrity of the arch rotation brackets at Wembley Stadium, undertaken by Bennett Associates, using YS software, which simulated the stresses on the brackets that hold and move the distinctive arches above the stadium.

7. 3D Modelling

Planning and building innovation has been driven by the growth of smart cities. CyberCity3D (CC3D) is a geospatial-modelling innovator specialising in the production of smart 3D building models. It creates smart digital 3D buildings to help the architectural, engineering and construction sector visualise and communicate design and data with CC3D proprietary software. The models integrate with 3D geographic information system platforms, such as Autodesk and ESRI, and can stream 3D urban building data to Cesium’s open architecture virtual 3D globe. It provides data for urban, energy, sustainability and design planning, and works in conjunction with many smart city SaaS platforms such as Cityzenith.

8. Modular Construction

Modular construction is one of the most popular developments in civil engineering where a building is constructed off-site using the same materials and designed to the same standards as conventional on-site construction. This innovative building technique limits environmental disruption, delivering components as and when needed, and turning construction into a logistics exercise. It also has strong sustainability benefits, from fewer vehicle movements to less waste. With up to 70 per cent of a building produced as components, it allows a move towards “just in time” manufacturing and delivery. In use in the United States and UK, Chinese developer Broad Sustainable Building recently completed a 57-storey skyscraper in 19 working days using this method.

9. Cloud Collaboration

Another new technology used in civil engineering is a cloud collaboration tool called base-stone. Base-stone is a system allowing the remote sharing of data on a construction site in real time. It is predominantly a review tool for civil engineers and architects which digitalises the drawing review process on construction projects, and allows for better collaboration. The cloud-based collaboration tool is focused on the installation of everything from steel beams to light fittings. The system is used to add “snags”, issues that happen during construction, on to pdfs, then users can mark or add notes through base-stone. Trials have revealed possible cost-savings of around 60 per cent compared with traditional paper-based review methods.

10. Asset mapping

Not all of the latest civil engineering developments are new construction materials or flashy technological tools. Asset mapping focuses on operational equipment, including heating and air conditioning, lighting and security systems. The process includes collecting data from serial numbers, firmware, engineering notes of when it was installed and by whom, and combines all the data in one place. This system can show engineers in real time where the equipment needs to be installed on a map and, once the assets are connected to the real-time system using the internet of things these can be monitored via the web, app, and other remote devices and systems. It helps customers build databases of asset performance, which can assist in proactive building maintenance, and also reduce building procurement and insurance costs.

Q7) What is the ecosystem and what are its types?

 A7)

The ecosystem is the community of living organisms in conjunction with non-living components of their environment, interacting as a system.

There are two types of ecosystem:

Terrestrial Ecosystems

Terrestrial ecosystems are exclusively land-based ecosystems. There are different types of terrestrial ecosystems distributed around various geological zones. They are as follows:

Forest Ecosystem

A forest ecosystem consists of several plants, animals and microorganisms that live in coordination with the abiotic factors of the environment. Forests help in maintaining the temperature of the earth and are the major carbon sink.

Grassland Ecosystem

In a grassland ecosystem, the vegetation is dominated by grasses and herbs. Temperate grasslands, savanna grasslands are some of the examples of grassland ecosystems.

Tundra Ecosystem

Tundra ecosystems are devoid of trees and are found in cold climates or where rainfall is scarce. These are covered with snow for most of the year. The ecosystem in the Arctic or mountain tops is tundra type.

Desert Ecosystem

Deserts are found throughout the world. These are regions with very little rainfall. The days are hot and the nights are cold.

Aquatic Ecosystem

Aquatic ecosystems are ecosystems present in a body of water. These can be further divided into two types, namely:

Freshwater Ecosystem

The freshwater ecosystem is an aquatic ecosystem that includes lakes, ponds, rivers, streams and wetlands. These have no salt content in contrast with the marine ecosystem.

Marine Ecosystem

The marine ecosystem includes seas and oceans. These have a more substantial salt content and greater biodiversity in comparison to the freshwater ecosystem.

Q8) What are the functions of ecosystem?

 A8)

The functions of the ecosystem are as follows:

1. It regulates the essential ecological processes, supports life systems and renders stability.

2. It is also responsible for the cycling of nutrients between biotic andabiotic components.

3. It maintains a balance among the various trophic levels in the ecosystem.

4. It cycles the minerals through the biosphere.

5. The abiotic components help in the synthesis of organic components that involves the exchange of energy.

Q9) What are the causes of global warming?

 A9)

Various human activities are responsible for global warming.

Deforestation

Plants are the main source of oxygen. They take in carbon dioxide and release oxygen thereby maintaining environmental balance. Forests are being depleted for many domestic and commercial purposes. This has led to an environmental imbalance, thereby giving rise to global warming.

Use of Vehicles

The use of vehicles, even for a very short distance results in various gaseous emission. Vehicles burn fossil fuels which emit a large amount of carbon dioxide and other toxins into the atmosphere resulting in a temperature increase.

Chlorofluorocarbon

With the excessive use of air conditioners and refrigerators, humans have been adding CFCs into the environment which affects the atmospheric ozone layer. The ozone layer protects the earth surface from the harmful ultraviolet rays emitted by the sun. The CFCs has led to ozone layer depletion making way for the ultraviolet rays, thereby increasing the temperature of the earth.

Industrial Development

With the advent of industrialization, the temperature of the earth has been increasing rapidly. The harmful emissions from the factories add to the increasing temperature of the earth.

In 2013, the Intergovernmental Panel for Climate Change reported that the increase in the global temperature between 1880 and 2012 has been 0.9 degrees Celsius. The increase is 1.1 degrees Celsius when compared to the pre-industrial mean temperature.

Agriculture

Various farming activities produce carbon dioxide and methane gas. These add to the greenhouse gases in the atmosphere and increase the temperature of the earth.

Overpopulation

Increase in population means more people breathing. This leads to an increase in the level of carbon dioxide, the primary gas causing global warming, in the atmosphere.

Q10) What are the major effects of global warming?

 A10)

Following are the major effects of global warming:

Rise in Temperature

Global warming has led to an incredible increase in earth’s temperature. Since 1880, the earth’s temperature has increased by ~1 degree. This has resulted in an increase in the melting of glaciers, which have led to an increase in the sea level. This could have devastating effects on coastal regions.

Threats to the Ecosystem

Global warming has affected the coral reefs that can lead to a loss of plant and animal lives. Increase in global temperatures has made the fragility of coral reefs even worse.

Climate Change

Global warming has led to a change in climatic conditions. There are droughts at some places and floods at some. This climatic imbalance is the result of global warming.

Spread of Diseases

Global warming leads to a change in the patterns of heat and humidity. This has led to the movement of mosquitoes that carry and spread diseases.

High Mortality Rates

Due to an increase in floods, tsunamis and other natural calamities, the average death toll usually increases. Also, such events can bring about the spread of diseases that can hamper human life.

Loss of Natural Habitat

A global shift in the climate leads to the loss of habitats of several plants and animals. In this case, the animals need to migrate from their natural habitat and many of them even become extinct. This is yet another major impact of global warming on biodiversity.