Dear Er. Kulkarni,
The Newsletter (Volume 1, No.3) contained several good and informative articles. Your paper on ”Water requirements of the Concrete Industry in India” was marvellous! Congratulations! I took some extracts from these articles and posted them on LinkedIn.
Dr. N. Subramanian,
Gaithersburg, Maryland, USA
Dear Sir,
I have gone through LCCF’s Volume 1, 2nd No. issue.
The article presents a brief account of this retrofitting exercise by CII-GBC. I like the concept of material efficient design – not only from structural point of view, but also from the architectural consideration. To implement such design, we must also have better engineering practices on site.
Some of my more thoughts…..
- I always wonder why all structures to be designed for say a service life of 100 years?
- Why builders spend on so much of time and money in finishing the flats and later 50 to 60 % of residents break most of it in name of interior work!!
- We are today witnessing a large no of redevelopment projects. Old buildings – even those in good conditions – are being demolished for constructing high rise buildings! It is like double dhamaka! All that debris is filled or dumped at unauthorised places!!
Hemant Joshi,
Pune
Dear Sir,
Hearty congratulations for the Volume 1, No.2 of LCCF Newsletter. I have read with interest the thought-provoking Edit and the development of Nano concrete aggregates.
However, I have need one clarification on the special feature ‘Advancing Net Zero Energy Buildings in India’ contributed by S Karthikeyan and Shivraj Dhaka. The article describes retrofitting measures of CIII-GBC headquarter building into a net-zero operational energy building and further states that more than 25 such net-zero operational energy building projects are being presently undertaken. Unfortunately, article is silent about the cost economics of the retrofitting exercise. Also, it does not mention the period required for recovering the investment made for retrofitting.
I request the authors to kindly throw light on the above aspects.
J.M.
Mumbai
Dear Sir,
Thanks for sharing the feedback. Specifically we did not want to talk about the cost economics in this article, because we believed that the attention would completely get diverted to costing instead of the technical feasibility of the whole concept.
Typically, the energy efficiency measures for reducing the energy consumption is very attractive. The building projects implement the energy efficiency measures only if the payback period is less than 2 to 3 years. All the projects implemented in our building also had the similar payback period of less than 3 years. We invested about Rs 75 lakhs for improving energy efficiency including replacement of the old inefficient chiller of capacity about 50 TR and other measures related to lighting systems, pumps etc.
The investment for renewable energy generation will have longer payback period depending upon the generation potential and the tariff regime in their state etc. In our case the payback period is about 7 years and we invested about Rs 125 Lakhs for installing renewable energy generation capacity of about 135 KWp. Still it is attractive considering the life cycle cost.
Hope this meets his requirement.
S Karthikeyan
Principal Counsellor, CII-Godrej Green Business Center, Hyderabad
Dear Er. Kulkarni,
I have gone through the copy of the LCCF Newsletter (Vol.1, No.1). Congratulations for the efforts! I am sharing some of my views on the subject.
- LCCF will be concerned with the life-cycle costs of structures.
- Is it possible to design our structures in such a way that instead of demolishing a sound structure we could use it for a different category of occupancy? (Office building to parking or light warehousing etc.,)
- Concrete has a high thermal resistivity. But we continue to design only simply supported bridges with expansion joints. World over, the costs of repairing/rehabilitating these bridges have been spiralling. The trend is to go for monolithic construction, without bearings. We have been designing such structures for over 40 years. Such structures are elegant and durable. They also perform much better during seismic events.
- Masonry structures have a long life. And yet many bridges were declared unsafe in Mumbai due to an unfortunate collapse of part of a concrete deck slab of a steel bridge that is comparatively younger than many steel bridges in Mumbai. Without exception, all these bridges could have been retrofitted. But our authorities are not interested.
- In some sense, our civil engineering fraternity has abdicated its responsibilities.
- Some new materials/technologies are emerging – Ultra-High Performance Fibre Reinforced Concrete (UHPFC). These are comparatively lighter. We can have larger spans leading to fewer foundations. Because of negligible creep and shrinkage, these can be combined with cast-in-place monolithic piers (HPC). UHPFRC consumes a substantial amount of copper fibres which will add to the CF. One has to evaluate such structures by assessing the life-cycle cost. A four-lane bridge with two spans of 55 m has been recently completed, load tested, and commissioned in Latur in Maharashtra. This was a joint effort of DURA (Malaysia), SDPL (Pune), SPACPL, and HSS (Malaysia).
Dr Vasudev V Nori
Chairman, Shirish Patel & Associates, Mumbai
Dear Sir,
I have gone broadly gone through the contents of the LCCF website. Congratulations on your valuable initiative. The undersigned will be keenly interested in participating in your activities.
Kindly enrol me as your member.
Best wishes,
V.N.H.
Dear Sir,
I have found LCCF website quite informative. However, you have not given due importance to the topic of material recycling – mainly the use of construction and demolition waste.
I stay in a metropolitan city. Currently, a lot of re-development work of old buildings is in progress. A number of buildings from our locality are getting demolished to make room for high-rise towers. Many of these buildings appear to be in good condition from the point of structural safety. Yet, they are getting demolished as the redevelopment is possibly rewarding to both the occupants and builder!
Further, as I understand, the demolished material is just getting dumped on the outskirts of the city without getting processed!
Why can’t we recycle the demolition waste in a scientific way to extract useful materials from it?
I suggest that LCCF should concentrate on this issue.
Thanks,
A.B.S.
Dear Sir,
Hearty congratulations on publication of LCCF website.
I am a student of civil engineering. We are located in drought-prone area and experience severe shortage of water, mainly during summer.
LCCF website does not include useful
information of water recycling. Can we use recycled grey water for construction – mainly for curing of concrete?
The website should provide approrpiate guidance of how to conserve water and whether we can use of grey water for construction.
Best regards,
B. D.
Dear Sir,
Heartiest congratulations for the inaugural issue of “LCCF Newsletter”. It aptly highlights current scenario, action required and news. However, you may kindly throw more light on what the civil engineering fraternity doing globally with respect to the reduction in carbon footprints. Also please share link for two virtual sessions done by you recently.
I am giving below some of my stray thoughts on the topic of carbon footprints reduction:
Materials - LCCF should highlight how different materials can be used which have lower embodied carbon such as Hemp, Recycled material, Earth, Bamboo, Cement , natural paints instead of VOC, use of insulation and improved window design, and more……
Design - Use of ferrocement , Precast, Modular, 3D , Use of arches needs to be promoted….. wherever applicable
Construction: Refurbishment and retrofitting of existing structures, monitoring and timely repair of infrastructure such as bridges, use of new technologies, application of IGBC Guidelines to reduce operational carbon footprints , inclusion of life cycle in overall costing from end of process case, due consideration to the ‘end of product phase’ for each application before the design gets finalized ……
Besides this, we need to develop:
Industries which specialize in collection and recycling of demolition waste
Institutes that provide guidance on LCA, and focus on using design, material and process with minimal carbon foot print
Codes and specifications to include best practices
Software such as STAAD/REVIT to include LCA of materials to know cost
Repository of EPD of materials as applicable to local conditions prevailing in India.
Thanks and Regards,
Ms Tanuja Singh
General Manager, Doosan Power System India Pvt Ltd