The Serial Innovator
RAILWAYS & METRO RAIL

The Serial Innovator

In this series of interviews with prominent civil engineers, Janaki Krishnamoorthi meets Dr Narayan Nayak, Principal Advisor, Gammon India Ltd and Managing Director, Gammon Realty Ltd.

It was sheer passion for knowledge that propelled a young boy to walk 12 km to school every day. And, Dr Narayan Nayak, Principal Advisor, Gammon India and Managing Director, Gammon Realty Ltd, went on to become the first civil engineer from his village Baggon in Karnataka. Born in a milieu where education was not a priority and business acumen clearly scored over education, he firmly stood his ground. He went on to do his MTech from IIT-Bombay and went much beyond and obtained a doctorate in civil engineering from the University of Wisconsin, USA. Remarkable indeed!

Beginning his career with teaching at his alma mater, Veermata Jijabai Technological Institute (VJTI), Mumbai, Dr Nayak secured a teaching assistantship while doing his PhD at the University of Wisconsin and subsequently worked at the University of Panama. Shortly after returning to India he moved from academia to industry.

"Initially, I was keen on teaching, but I was soon disillusioned by the Indian education system. We are not allowed to go beyond the syllabus, and there was little room to teach anything new or innovative," laments Dr Nayak. Academia's loss was industry's gain. In his industrial career spanning four decades, he introduced several innovative techniques in construction, particularly in the geotechnical field, like the development and execution of cement bentonite slurry walls, high pressure jet grouting, rammed stone columns, well resting on pile foundation, etc. He also instituted diverse methods to achieve high performance and sustainable concrete, which are chronicled in the book Handbook on Advanced Concrete Technology, co-authored and co-edited by him. His other popular book Foundation Design Manual talks about foundation techniques, design and practices.

Not surprising then, many of his projects, ranging from flyovers, bridges, metros to dams, marine and industrial structures have some innovative element in them. His notable projects include the JJ Flyover in Mumbai, Thane Creek Bridge, Kolkata Metro, Kaiga Atomic Power Plant in Karnataka, 24 Konkan Railway bridges, the Godavari Bridge, multipurpose berths at Visakhapatnam Port Trust, etc.

Innovation, quality, speed, safety and sustainability are his professional mantras. "Innovations automatically increase durability and reduce costs and execution time. Earlier, concrete structures had a life span of 40 to 50 years; but today, with new materials and innovative techniques, we can increase that to 100 years," he avers.

He, however, concedes that there is considerable resistance from the government, developers and even civil engineers to new techniques and materials. "Moreover, archaic building codes often compel us to adopt outdated or incorrect practices. There is an urgent need to revise these codes," he asserts. But, he is in no way disheartened, adding, "On the contrary, it makes me more determined." Today, at the age of 76, Dr Nayak, who is more resolute than ever, shares his views and experiences with CW on issues related to engineering and construction.

Sustainable strategies

Sustainable construction aims at preserving the environment. Hence, judicious use of cement and steel is a must today as their production is severely polluting our environment. The government, however, is planning to increase cement production from the existing 230 mtpa to 500 mtpa by 2020. As such, cement units together are emitting 0.65 million tonne of carbon dioxide daily into the atmosphere. Why make it worse when we can produce more concrete without increasing cement production? Several other cementitious materials like flyash, GGBS (ground granulated blast-furnace slag), can not only replace cement but also produce more durable, economical and greener concrete. We can replace 70 per cent of cement with GGBS and 35 per cent with flyash as per Indian codes. Yet, there are not many takers. Many developed countries encourage the use of such substitute materials, and it is mandatory in certain countries. But, in India unfortunately, there is a strong cement lobby.

Significant shifts

The construction industry has witnessed several significant changes in the last few years. There is substantial quality improvement in structures and super structures. Projects are executed faster. For instance, the Zuari Road Bridge (Goa), which in the 80s, took us more than 10 years to complete, can be constructed in two years today.

Self-compacting concrete is the greatest technical advancement with its flowing and filling ability, self-compacting without segregation, ie, maintaining homogeneity, etc. It is more durable, with better surface finish, reduces cost, equipment and manpower usage and allows for proper compaction even in congested areas.

Perfect piling

In pile foundation, several issues that can affect the quality of piling are often neglected. Some of them are:

Faulty use of binding wire: While using the binding wire (generally mild steel) on the reinforcement cage, one should ensure that the loose ends project inwards and not outwards. Secondly, only the essential length of wire should be used, otherwise the long, unbound wires with less concrete cover or projecting beyond the concrete cover may start corroding at an early stage.
Poor quality concrete cover block : The grade of concrete, water-cement ratio, cement type and content, etc, of these concrete cover blocks should be the same as that of pile concrete. Further, these blocks should be properly compacted and cured in a tank for a minimum of seven days. Often, concrete blocks are cast without giving due attention to the above facts, and compaction or vibrations of concrete in cover blocks is practically neglected. This results in cover blocks that are full of voids, with lower strength concrete, higher water-cement ratio, etc.

Poorly designed concrete mix: The general procedure is to use M20 grade concrete. BIS allows (in IS 2911 Part III under Reamed Piles) even M15 concrete. Since piles are increasingly used in an aggressive/corrosive subsurface environment, one should use at least M30 or higher grade concrete. Further, with BIS specifying a minimum 350 kg of cement per cubic metre of concrete in cast-in-situ piles, it is possible to achieve M35 or M40 grade of concrete with this cement content.

For cast-in-situ piling, we need high slump concrete in the order of 150-180 mm. The general tendency is to use more water as even BIS permits a water-cement ratio of more than 0.5. However, for durable pile concrete, the water-cement ratio should prefer-ably be less than 0.4. Hence, it is advisable to use plasticisers to achieve the desired workability with a low water-cement ratio.

Improper chipping of pile above cut-off: In in-situ pile concreting, the concrete above the cut-off level is chipped off, often after the concrete has attained considerable strength, resulting in numerous fine cracks in good concrete below the cut-off level.

I have developed a technique that ensures dense concrete without micro-cracks. As soon as the concreting is completed, the excess concrete, still with high slump of the order of 75 to 100 m, is bailed out using a smaller diameter bailer or by other means, practically up to the cut-off level. Then, the concrete is rammed using a rammer with spikes to ensure dense concrete at the top. This eliminates the possibility of air voids in the concrete.

Track record: Narayan Venkatesh Nayak

Education
1959: BE (Civil) from VJTI Mumbai
1963: MTech from IIT-Bombay
1970: PhD from University of Wisconsin, USA

Academic:
1963-1967: Lecturer, VJTI, Mumbai
1967-1970: Teaching Assistant and PhD student, University of Wisconsin, USA
1970-1972:  Professor, University of Panama

Industry:
1972-1979: *Principal Engineer, Tata Consulting Engineers, Mumbai
1980-1995: *Director-Projects, Afcons Ltd
1996-2004: *Deputy Managing Director, Gammon India  
2010 till date: *Principal Advisor, Gammon India
2010 till date : Managing Director, Gammon Realty
2010 till date: Chairman-Advisor, Geocon International Pvt Ltd
Authored Foundation Design Manual and co-authored and co-edited Hand Book on Advanced Concrete Technology (6th edition)

* Last position held

Recognitions

• First annual lecturer from the construction industry to be selected by the Indian Geotechnical Society (1994)
• First recipient from the construction industry to receive the Kueckelmann Award from the Indian Geotechnical Society (1994-95)
• Kanara Ratna Award from Kanara College Society (2011)

Challenging projects

Project: Zuari Bridge, Konkan Railway, Goa
Project Period: 1996-1999
Client: Konkan Railway Corporation Ltd
Contractor: Afcons Ltd
Salient features: The longest bridge in Goa stretching across 1,319 m with central span equal to 2 x 123.2 m. In navigation channels where the span is 120 m, steel trusses were used. Other spans are equal to pre-stressed box girders or I-girders on pile foundations or open foundations.
Innovation: In some navigational channels, the strata was poor, and hence, a new method of foundation was used. "In such channel portions, where wells were required to be founded, sinking by pneumatic method 30 m below water level – a novel technique of resting the well on the pile foundation – was adopted, enabling wells to be sunk to 20 m below the water level. This technology was introduced and implemented successfully for the first time in the world," reveals Dr Nayak.
Challenges: Completing the project within the timeframe was a challenge in itself. Launching the concrete girder in position was another difficult task, but their earlier experience in Thane Creek Bridge came in handy. The most difficult one, of course, was the well on-pile foundation. "It was a major challenge, since we were executing it for the first time. But, everything went off smoothly due to meticulous planning and execution," avers Dr Nayak.

Project: Multipurpose berths at Visakhapatnam Port   
Client: Visakhapatnam Port Trust (VSPL)   
Contractor: Gammon India
Period: 2000-2004
Background: Gammon India was entrusted with the task of developing two multipurpose berths on BOT (build, operate and transfer) basis. Both the berths along with the terminal were to be an integrated system with state-of-the-art technologies.  
Innovation: Replacing 70 per cent of cement by GGBS was a major innovation. Ground improvement by band drains, rarely undertaken, was another interesting aspect.  
Challenges: Convincing the client to permit the use of GGBS was a major challenge, more so since the project specifications did not permit its use. "GGBS was easily available in Vizag, and since its usage would produce durable green concrete, I suggested substituting 70 per cent of the cement with GGBS. Since the officers at the lower level were not ready for it, I took it up with SR Rao, then the Chairman of VSPL. He asked me to make a presentation to his technical staff, after which, the Chief Engineer of VSPL confirmed that it was better quality concrete but pointed out that the project specifications did not permit it. But Rao, known for his bold decisions, took the responsibility and asked us to go ahead once I assured him that it will not increase the cost in any way," recalls Dr Nayak.

To share your engineering experiences with us, write in at feedback@ASAPPmedia.com

In this series of interviews with prominent civil engineers, Janaki Krishnamoorthi meets Dr Narayan Nayak, Principal Advisor, Gammon India Ltd and Managing Director, Gammon Realty Ltd.It was sheer passion for knowledge that propelled a young boy to walk 12 km to school every day. And, Dr Narayan Nayak, Principal Advisor, Gammon India and Managing Director, Gammon Realty Ltd, went on to become the first civil engineer from his village Baggon in Karnataka. Born in a milieu where education was not a priority and business acumen clearly scored over education, he firmly stood his ground. He went on to do his MTech from IIT-Bombay and went much beyond and obtained a doctorate in civil engineering from the University of Wisconsin, USA. Remarkable indeed!Beginning his career with teaching at his alma mater, Veermata Jijabai Technological Institute (VJTI), Mumbai, Dr Nayak secured a teaching assistantship while doing his PhD at the University of Wisconsin and subsequently worked at the University of Panama. Shortly after returning to India he moved from academia to industry.Initially, I was keen on teaching, but I was soon disillusioned by the Indian education system. We are not allowed to go beyond the syllabus, and there was little room to teach anything new or innovative, laments Dr Nayak. Academia's loss was industry's gain. In his industrial career spanning four decades, he introduced several innovative techniques in construction, particularly in the geotechnical field, like the development and execution of cement bentonite slurry walls, high pressure jet grouting, rammed stone columns, well resting on pile foundation, etc. He also instituted diverse methods to achieve high performance and sustainable concrete, which are chronicled in the book Handbook on Advanced Concrete Technology, co-authored and co-edited by him. His other popular book Foundation Design Manual talks about foundation techniques, design and practices.Not surprising then, many of his projects, ranging from flyovers, bridges, metros to dams, marine and industrial structures have some innovative element in them. His notable projects include the JJ Flyover in Mumbai, Thane Creek Bridge, Kolkata Metro, Kaiga Atomic Power Plant in Karnataka, 24 Konkan Railway bridges, the Godavari Bridge, multipurpose berths at Visakhapatnam Port Trust, etc.Innovation, quality, speed, safety and sustainability are his professional mantras. Innovations automatically increase durability and reduce costs and execution time. Earlier, concrete structures had a life span of 40 to 50 years; but today, with new materials and innovative techniques, we can increase that to 100 years, he avers.He, however, concedes that there is considerable resistance from the government, developers and even civil engineers to new techniques and materials. Moreover, archaic building codes often compel us to adopt outdated or incorrect practices. There is an urgent need to revise these codes, he asserts. But, he is in no way disheartened, adding, On the contrary, it makes me more determined. Today, at the age of 76, Dr Nayak, who is more resolute than ever, shares his views and experiences with CW on issues related to engineering and construction.Sustainable strategiesSustainable construction aims at preserving the environment. Hence, judicious use of cement and steel is a must today as their production is severely polluting our environment. The government, however, is planning to increase cement production from the existing 230 mtpa to 500 mtpa by 2020. As such, cement units together are emitting 0.65 million tonne of carbon dioxide daily into the atmosphere. Why make it worse when we can produce more concrete without increasing cement production? Several other cementitious materials like flyash, GGBS (ground granulated blast-furnace slag), can not only replace cement but also produce more durable, economical and greener concrete. We can replace 70 per cent of cement with GGBS and 35 per cent with flyash as per Indian codes. Yet, there are not many takers. Many developed countries encourage the use of such substitute materials, and it is mandatory in certain countries. But, in India unfortunately, there is a strong cement lobby.Significant shiftsThe construction industry has witnessed several significant changes in the last few years. There is substantial quality improvement in structures and super structures. Projects are executed faster. For instance, the Zuari Road Bridge (Goa), which in the 80s, took us more than 10 years to complete, can be constructed in two years today.Self-compacting concrete is the greatest technical advancement with its flowing and filling ability, self-compacting without segregation, ie, maintaining homogeneity, etc. It is more durable, with better surface finish, reduces cost, equipment and manpower usage and allows for proper compaction even in congested areas.Perfect pilingIn pile foundation, several issues that can affect the quality of piling are often neglected. Some of them are:Faulty use of binding wire: While using the binding wire (generally mild steel) on the reinforcement cage, one should ensure that the loose ends project inwards and not outwards. Secondly, only the essential length of wire should be used, otherwise the long, unbound wires with less concrete cover or projecting beyond the concrete cover may start corroding at an early stage.Poor quality concrete cover block : The grade of concrete, water-cement ratio, cement type and content, etc, of these concrete cover blocks should be the same as that of pile concrete. Further, these blocks should be properly compacted and cured in a tank for a minimum of seven days. Often, concrete blocks are cast without giving due attention to the above facts, and compaction or vibrations of concrete in cover blocks is practically neglected. This results in cover blocks that are full of voids, with lower strength concrete, higher water-cement ratio, etc.Poorly designed concrete mix: The general procedure is to use M20 grade concrete. BIS allows (in IS 2911 Part III under Reamed Piles) even M15 concrete. Since piles are increasingly used in an aggressive/corrosive subsurface environment, one should use at least M30 or higher grade concrete. Further, with BIS specifying a minimum 350 kg of cement per cubic metre of concrete in cast-in-situ piles, it is possible to achieve M35 or M40 grade of concrete with this cement content.For cast-in-situ piling, we need high slump concrete in the order of 150-180 mm. The general tendency is to use more water as even BIS permits a water-cement ratio of more than 0.5. However, for durable pile concrete, the water-cement ratio should prefer-ably be less than 0.4. Hence, it is advisable to use plasticisers to achieve the desired workability with a low water-cement ratio.Improper chipping of pile above cut-off: In in-situ pile concreting, the concrete above the cut-off level is chipped off, often after the concrete has attained considerable strength, resulting in numerous fine cracks in good concrete below the cut-off level.I have developed a technique that ensures dense concrete without micro-cracks. As soon as the concreting is completed, the excess concrete, still with high slump of the order of 75 to 100 m, is bailed out using a smaller diameter bailer or by other means, practically up to the cut-off level. Then, the concrete is rammed using a rammer with spikes to ensure dense concrete at the top. This eliminates the possibility of air voids in the concrete.Track record: Narayan Venkatesh NayakEducation1959: BE (Civil) from VJTI Mumbai 1963: MTech from IIT-Bombay1970: PhD from University of Wisconsin, USAAcademic: 1963-1967: Lecturer, VJTI, Mumbai1967-1970: Teaching Assistant and PhD student, University of Wisconsin, USA1970-1972:  Professor, University of PanamaIndustry: 1972-1979: *Principal Engineer, Tata Consulting Engineers, Mumbai1980-1995: *Director-Projects, Afcons Ltd1996-2004: *Deputy Managing Director, Gammon India  2010 till date: *Principal Advisor, Gammon India 2010 till date : Managing Director, Gammon Realty 2010 till date: Chairman-Advisor, Geocon International Pvt LtdAuthored Foundation Design Manual and co-authored and co-edited Hand Book on Advanced Concrete Technology (6th edition)* Last position heldRecognitions• First annual lecturer from the construction industry to be selected by the Indian Geotechnical Society (1994)• First recipient from the construction industry to receive the Kueckelmann Award from the Indian Geotechnical Society (1994-95) • Kanara Ratna Award from Kanara College Society (2011)Challenging projectsProject: Zuari Bridge, Konkan Railway, GoaProject Period: 1996-1999Client: Konkan Railway Corporation LtdContractor: Afcons LtdSalient features: The longest bridge in Goa stretching across 1,319 m with central span equal to 2 x 123.2 m. In navigation channels where the span is 120 m, steel trusses were used. Other spans are equal to pre-stressed box girders or I-girders on pile foundations or open foundations.Innovation: In some navigational channels, the strata was poor, and hence, a new method of foundation was used. In such channel portions, where wells were required to be founded, sinking by pneumatic method 30 m below water level – a novel technique of resting the well on the pile foundation – was adopted, enabling wells to be sunk to 20 m below the water level. This technology was introduced and implemented successfully for the first time in the world, reveals Dr Nayak. Challenges: Completing the project within the timeframe was a challenge in itself. Launching the concrete girder in position was another difficult task, but their earlier experience in Thane Creek Bridge came in handy. The most difficult one, of course, was the well on-pile foundation. It was a major challenge, since we were executing it for the first time. But, everything went off smoothly due to meticulous planning and execution, avers Dr Nayak.Project: Multipurpose berths at Visakhapatnam Port   Client: Visakhapatnam Port Trust (VSPL)   Contractor: Gammon India Period: 2000-2004Background: Gammon India was entrusted with the task of developing two multipurpose berths on BOT (build, operate and transfer) basis. Both the berths along with the terminal were to be an integrated system with state-of-the-art technologies.  Innovation: Replacing 70 per cent of cement by GGBS was a major innovation. Ground improvement by band drains, rarely undertaken, was another interesting aspect.  Challenges: Convincing the client to permit the use of GGBS was a major challenge, more so since the project specifications did not permit its use. GGBS was easily available in Vizag, and since its usage would produce durable green concrete, I suggested substituting 70 per cent of the cement with GGBS. Since the officers at the lower level were not ready for it, I took it up with SR Rao, then the Chairman of VSPL. He asked me to make a presentation to his technical staff, after which, the Chief Engineer of VSPL confirmed that it was better quality concrete but pointed out that the project specifications did not permit it. But Rao, known for his bold decisions, took the responsibility and asked us to go ahead once I assured him that it will not increase the cost in any way, recalls Dr Nayak.To share your engineering experiences with us, write in at feedback@ASAPPmedia.com

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