Civil Engineering: Past, Present, and Future; Dr. N. Subramanian

Civil Engineering: Past, Present, and Future; Dr. N. Subramanian

Abstract:

In the past 50 years of my life I have witnessed several changes in Civil Engineering. Civil Engineering is a vast field encompassing several sub fields such as Structural Engineering, Material Science, Soil mechanics and foundation engineering, Hydraulic engineering,  Environmental engineering, Traffic and transportation engineering, Earthquake engineering,  Construction engineering, Urban Engineering, Forensic engineering, and  Coastal engineering. It is impossible to review the developments in all these fields in such a short communication. As I am a structural engineer, I have tried to review the developments in structural engineering, which I witnessed along my life journey.

WHAT WE SAW ALREADY

About 50 years ago, when I joined Thiagarajar College of Engineering in 1967, for doing Engineering, there were only seven engineering colleges in Tamilnadu. I belonged to the integrated course, in which the exams were conducted at the end of the year and the course was of 5 years duration. (we studied up to 11th standard in school and then studied Pre University Course (PUC) in a private Arts college, before joining the Engineering College-now that system is changed to 10 plus 2 years of schooling, and then joining Engineering college). From 1972 onwards the semester system was introduced and subsequently the course was shortened to four years, after removing some important courses like Engineering drawing, and some other practical periods like surveying. We studied general subjects till the second year and chose the branch only from the third year. There was a Project work in the fifth year, and I did the work of designing a new Bus Terminus in Madurai, and a few years later the Terminus was built-but not sure whether our designs were used!

When we studied there were no computers and we used slide rules to do the calculations in the examinations (see Fig. 1). Some failed or scored less marks due to the mistakes they committed in operating the slide rules, as fixing of decimal point is difficult using these aids.

Fig. 1 The Slide Rule.

When we finished college, even before the exam results came, all were given job in Tamilnadu Water Supply and Drainage Board; many of my class mates retired as Chief Engineer/Superintending Engineers from Government Departments. Working stress method was taught and used in practice. Hand calculations were the norm.

I joined the College of Engineering, Guindy (CEG)-one of the oldest in India and established in 1794- for my Masters degree in Structural Engineering in 1972. Again the course was of 2 years duration, with the last semester consisting of Thesis work (now it is only 1.5 years duration).  At that time CEG had a second generation computer (IBM 1620) and the input was through computer cards, the programs have to be punched in cards using a card punching machine-Which can be seen now only in museums (see Fig. 2 and 3). We used it as a part of the Numerical methods in engineering Course work. At that time we used the FORTRAN language for programming the computer.

In 1974, I joined Indian institute of Technology, Madras for my Ph.D. work. At that time there was a centralized computer center with IBM 370 Computer (third generation). It also had card input. For jobs involving larger storage area, we had to stand in the queue at the start of the day and give the card deck to the operator (we were not allowed to go inside and work with the computer), who will feed and give the output in the afternoon-if there were errors, the necessary cards have to be repunched and given to the operator the next day only! Sometimes, due to the error in the card reader, some cards will be misplaced or damaged, and it will take a number of days to rearrange the card deck. As my thesis involved three dimensional analyses and hence, I used maximum core space and time of the system, which resulted in myself going very early in the morning to give my card deck for processing!

Fig. 3 Card Punching Machines
Fig 2. Punching positions in card

 

 

 

 

 

 

 

After finishing my Ph.D, I worked as a Post-Doctoral Fellow in IITM, in the Civil Engineering Department, and for a few months in the newly formed Ocean Engineering Department. Based on my international publications, I was invited by the prestigious Alexander von Humboldt Foundation to work in the then West Germany, as a research Fellow. After learning the German Language in the famous Goethe Institute in the city of Freiburg, for 4 months I moved to the Technical University of Berlin (At that time the infamous Berlin wall was there) to do research on Cold formed Steel Sections. During that time a number of steel sections were tested in the universities of Europe as the German Steel Code was under revision (In addition, starting in 1975, the European Commission, with the help of a steering committee, was developing the  Eurocodes (for fifteen years), which led to the first generation of European codes in the 1980. By 2002, ten sections of Eurocodes had been developed and published.

In 1982, I started my own consulting firm. Ours may be the first in India to have an in-house computer. It was an UPTRON S-800 system, which we bought for Rs. 5 lakhs and sold for a mere Rs. 5000 after a few years. I wrote FORTRAN and BASIC programs for the analysis and design of Structures and elements like beams, columns, slabs, foundations, etc. IBM PCs were introduced and used only around 1984. At that time the hardware was expensive and no one cared to pay money for software. Standard software like STAAD, SAP etc., appeared much later.  Soon, the drawing boards in consulting offices were replaced by computers using the AutoCad software.

WHAT IS HAPPENING NOW

After successfully running the consultancy organization for 26 years, I closed it in 2008. I am now retired and living in USA from 2004. The following observed by me are the happening in the past 8 to 10 years.

The design codes, which were in Working Stress Method format, have been changed to Limit States Method format, due to the extensive experimental and theoretical investigations conducted world over on the behavior concrete and steel structures.   

Almost all design firms are now equipped with powerful computer systems with general purpose finite-element computer software. Most of the firms analyze structures as three-dimensional systems. A number of general purpose software capable of doing non-linear analysis, dynamic analysis and even buckling analysis are being used. Special software that convert the output of these packages into detailed drawings are also available. In addition for routine design calculations, spread sheets are widely used.

Realizing the capability of such hardware and software systems, Architects are now designing and conceiving daring structures, which were not considered in the last decade. Unprecedented research has happened in the past few years all over the world on different aspects of Civil Engineering. The development of high strength and high performance materials have resulted in the construction of several astonishing structures, such as the 1,828 m tall Burj Khalifa, Dubai, completed in 2010(Tallest building in the world) and the 1,991 m span Akashi Kaikyō Bridge, Japan, completed in 1998 (World’s longest suspension bridge or unsupported span on a bridge).

Fig 4. Burj Khalifa, Dubai
Fig. 5 Akashi Kaikyō Bridge, Japan

 

 

 

 

 

 

 

Although, several outstanding structures have been built all over the world, the developing countries in particular, witnessed failures of structures, which were mainly due to human errors in design, during construction, and maintenance. Some failures are also due to over reliance of computer results and forgetting to check the basic behavior of structures.

Failures of bridges resulted in the development of structural health monitoring (SHM) systems, which are now used for the surveillance, evaluation and assessment of the condition of existing long-span bridges. Several important bridges are now equipped with these SHM systems. Examples include:  the Akashi Kaikyo Bridge,  the Great Belt East Bridge (1624 m, a suspension bridge in Denmark), the Normandie Bridge (856 m, a cable-stayed bridge in France), and  the I-35W Saint Anthony Falls Bridge(the original I-35W Mississippi River bridge collapsed in 2007)

Building information modeling (BIM), which has been used only in large buildings, is now developing into a building information science involving systematic theories, concepts, methods, technologies, applications and management for the digitization, visualization, quantitative analysis, and decision-making of whole project life cycles in the architecture, engineering and construction (AEC) industry.

One of the major advancements during the years is the development of Smart phones. They revolutionized the computer industry and the mode of communication itself. Several ‘Apps’ are now available in Smart phones which can aid the Civil Engineer. They include:  Civil Calculator, Civil Sutra, Civil Quantity Estimator, EpicFEM, Reinforced Concrete AutoCAD 360, and Civil Engineering Dictionary.

The society at large has recognized the importance of Sustainability, as there is only limited quantity of resources and they have to be preserved, so that future generations can enjoy their stay in this remarkable planet of ours, without any difficulty. Already several resources are in short-supply. For example, in many parts of India there is a scarcity of River sand, which is not only used in concrete but also in several other applications. Manufactured sand, which is nothing but crushed sand from rocks, crushed using Vertical shaft impact (VSI) crushers. Codes such as IS 383 also permit its use. Another big problem is the pollution of air, water and land by the emissions, and waste products from several industries. Waste products such as fly ash, ground granulated blast furnace slag (GGBS), silica fume, rice husk ash (RHA), high reactivity metakaolin (HRM), etc. are being used in concrete, which also improve its properties. Self compacting concrete (SCC), which does not require vibration but can fill all portions of concrete members with even congested reinforcement, will be used in all places due to its advantages.

There was a mushrooming growth of private Engineering colleges and even private Universities in India, which does not match with the jobs generated in the field for such engineers. Currently there are 10,396 Engineering colleges in India (Maharashtra-1564, Tamil Nadu 1339, Uttar Pradesh-1165, Andhra Pradesh-825, and Karnataka-756). Though the number of students coming out of these institutions are in large numbers, their standard is poor.  In order to rectify this situation and improve the standards of engineering practice, AICTE has introduced mandatory internship for students from the session 2017- 18. In addition, organizations such as the Engineering Council of India have initiated the Registration of Professional Engineers; in future the competence of those registering will be evaluated through written examination or interview. It is hoped that there will be continuing education programs, to make the senior engineers to be in touch with current developments.

FUTURE DEVELOPMENTS

It is not possible to predict the future. However, based on the ongoing research in some of the fields, I just want to list a few things that may become reality in future (already some of them have been realized in some pioneering projects.

Buildings which generate their own energy: In current building designs, buildings are oriented in such a way that the effects of wind are minimized. But in future, wind will not only be treated as an obstacle to overcome, but as a source of energy to be harnessed. Several skyscrapers have been constructed recently, which have integrated large wind turbines into their design (see Fig. 6).  Even small buildings will be equipped with solar or wind powered systems, which will make them self-sufficient in energy.

Fig. 6 (a) Bahrain World Trade Center 
Fig. 6 (b)Pearl River Tower, Guangzhou, China

 

 

 

 

 

 

 

Solar roads: China and France have developed solar roads. The recently opened 1-km long two-lane solar road in Jinan, south of Beijing in China, can generate up to 1 million KWH of power annually-enough to power 800 Chinese homes!

Super tall structures: The Skyscraper Center of CTBUH is has listed several super tall buildings, which are under construction, including the Jeddah tower, in Jeddah which will reach a height of 1000 m, when it is scheduled to open in 2021 (http://www.skyscrapercenter.com/buildings).

Fig.7 Rotating towers

Rotating towers: The Italian architect David Fisher, has conceived the idea of the 80-storey Rotating Tower, which is now underway in Dubai, UAE. Many more such rotating towers will be built, which will result in continuously changing views for the building occupants (Fig.7).

Use of Drones: According to a 2016 McKinsey report, unmanned aerial vehicles (UAVs), commonly referred to as drones, will dramatically improve the accuracy and speed at which construction projects are completed in the near future.

Fig. 8 Use of drones in Construction projects

 

Self healing Structures: Huge amounts are being spent on repairs and rehabilitation of structures, which are affected by corrosion reinforcement. In future, composites will be used which encapsulate healing agents and liberate upon fracture and heal the cracks. Bacteria embedded concrete are also being tried, which will act as healing agents and repair the cracks. Self curing of concrete may also be used widely.

New Materials: Several new materials including nano-materials, such as Graphene are being investigated – due to their unique combination of superb properties; they may be applied in a wide spectrum of applications ranging from civil engineering, electronics to optics, and sensors.

Innovative use of waste materials: Dr R Vasudevan, a chemistry professor and Dean at the Thiagarajar College of Engineering in Madurai, through trial and error, came up with the invention of plastic tar roads made with a discarded, low-grade polymer. These roads have already shown promise for long life without pot holes, and Dr Vasudevan was recently awarded the Padma Shree by the Indian Government.

It is also hoped that Civil Engineers will get their due recognition, when the Parliament passes the Engineer’s bill.

1 Comment

  1. Very informative

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