Dear Prof Ankur Bhogayata,
As you have highlighted, manufactured sand (crushed sand) is almost universally used, in Mumbai, besides "Fly Ash" and other chemical admixtures, in making of concrete, even up to M-50, by RMC Plants in Mumbai (India),. This so called manufactured sand, at times is seen with high contents of quarry dust, from crushing of stones for conversion into coarse aggregate. This material, at times is seen to contain a large percentage of "Fines," which are likely to interfere with formation of "gel", around cement particles, to bond & bind, the various ingredients to make concrete.
Besides this, as far as environment issues are concerned, this crushed sand, is primarily made from quarrying of rocks, which again are of natural formation. Are we not disturbing the ecology, in extracting the natural rock, by Open-cast Quarry, or Hill Slopes? Secondly, banning of dredging of natural sand from river beds, in long time, the beds of river will start rising, and with the yearly monsoon flow of natural rain water (which actually results in formation of granular natural sand), the river bed will tend to be shallow, and in the process, in ling run, flood the river-banks, and in far future, even result in change of its course.
A balance needs to be struck, so that we do not face a situation of "Devil OR Demon."
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SATISH DHUPELIA , PROPRIETOR
Consulting Structural ENGINEER
STRUCT-ARCH
MUMBAI, INDIA
+919820028705
SatishSatishSatish
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Original Message:
Sent: 11-15-2017 02:04
From: Ankur Bhogayata
Subject: green concrete
The word " Sustainability" carries a lot of varying meanings when used for the construction materials. Being specific to the concrete as a material, the intentions should be to reduce the carbon footprints of the production as well as during and after usage of the material. Concrete being a composite requires more than <g class="gr_ gr_324 gr-alert gr_gramm gr_inline_cards gr_run_anim Grammar multiReplace" id="324" data-gr-id="324">a single parameters</g> to be checked in this regard for being a sustainable material.
Now, with the emerging concepts of usage of industrial and <g class="gr_ gr_432 gr-alert gr_spell gr_inline_cards gr_run_anim ContextualSpelling ins-del multiReplace" id="432" data-gr-id="432">domasticwastes</g> in concrete has shown potential. second, usage of byproducts- <g class="gr_ gr_527 gr-alert gr_spell gr_inline_cards gr_run_anim ContextualSpelling ins-del multiReplace" id="527" data-gr-id="527">ingradients</g> such as artificial <g class="gr_ gr_612 gr-alert gr_gramm gr_inline_cards gr_run_anim Style replaceWithoutSep" id="612" data-gr-id="612">sand,fly</g> ash, or similar items are being utilized to reduce the energy needs by the concrete in terms of cement consumption in the mix. <g class="gr_ gr_911 gr-alert gr_gramm gr_inline_cards gr_run_anim Grammar multiReplace" id="911" data-gr-id="911">Third</g> is the usage of <g class="gr_ gr_868 gr-alert gr_gramm gr_inline_cards gr_run_anim Grammar multiReplace" id="868" data-gr-id="868">a hazardous wastes</g> in concrete makes it environment-friendly. extensive <g class="gr_ gr_931 gr-alert gr_spell gr_inline_cards gr_run_anim ContextualSpelling ins-del multiReplace" id="931" data-gr-id="931">reserach</g> work is going on for such emerging ideas and can be found on web resources and journals. All the best and keep your concern to the topic. . .
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Ankur Bhogayata Aff.M.ASCE
Associate Professor
Rajkot
Original Message:
Sent: 11-14-2017 05:36
From: Shaswat Das
Subject: green concrete
what is the newest technology used for environmentally sustainable concrete production ?
thank you
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Shaswat Das S.M.ASCE
Govt. College of Engineering , Keonjhar , Odisha
Keonjhar OR
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