Ferrocement Educational Forum
Welcome, Guest. Please login or register.
October 17, 2017, 04:29:46 PM

Login with username, password and session length
Search:     Advanced search
Check out the HELP ME I'M STUCK board for tips and help with forum options
2840 Posts in 449 Topics by 583 Members
Latest Member: componentfreak
* Home Help Search Calendar ArchivesFEN Home Login Register
Ferrocement Educational Forum  |  Ferrocement Discussions  |  Projects  |  Topic: Floating solar array in India « previous next »
Pages: [1] Print
Author Topic: Floating solar array in India  (Read 2692 times)
upston
Full Member
***
Posts: 97


« on: September 03, 2016, 10:27:39 AM »

Hi All,

I have been working on fitting out our Fibersteel 55 ft sail boat for the last three years so have been lax on the forum. That said I want to thank Paul for helping me with the lead on the boat and his ongoing encouragement on the project. I am getting close to the finish line and will do a full post on the Wild Goose soon. Special thanks as well to Colin King who worked on building the Goose in 1973 and has answered endless questions ,as we say in OZ "good on ya Col"

So back in January Paul gets me in Contact with an Indian fellow who has won a bid to build a 500 KW floating solar array in a hydro electric dam in south east India, Karella to be precise. The principal, Ronny, contacted me and after some coaxing I agreed to travel to the project site and " get them to the next level" on the LFC system. Martin Irons and Colin had set them up with a system to build floating hotel rooms at a resort back in the 90s so they had a baseline to build on but the new project was an order of magnitude bigger and more complicated than anything tackled so far.

The scope of the work is largest floating LFC project I am aware of since the Brits built the floating harbor at Normandy for the D day landing. The Mulberry as it was code named allowed the allies to unload all the equipment in deep water in a fraction of the time vs a direct beach approach requiring specialized vessels and all the obvious complications.

This floating array consists of 18 platforms rafted together and anchored in the man made lake. Two types of platforms make up the array, the first three coined Mother platforms are large flat topped barges upon which the "typical" 15 floats will be built and floated off as completed. These MP's are huge, 60 ft wide by 90 ft long and 7 ft tall. Each has five water tight compartments so they can be flooded and submerged to float off the typical float built on top. The 15 typical floats are a little smaller at 70 ft x 45 with four moon pools in each.

Martin had devised a brilliant but radical floating mold upon which to build the mother mold for the floating hotel rooms and the same process was to be used for the much larger MP's for the solar project. Ply sheets are laid over a waterproof membrane with a wood perimeter beam of 2x12's. Some minor framing connected this all together under the ply so that the top side was flat ready to pour the bottom slab of the MP. The base would be poured in two lifts and a complex pattern of 2x2" mesh and small rod reinforced the whole thing as lath is not available locally. This process was closer to traditional FC than LFC but Martin and Colin were working with what the had.

My first day on site was the eave of the first base pour on the first MP and I was eager to inspect the progress. The mold was located at the S/W end of the lake and was exposed to the full force of the afternoon breeze which kicked up small but constant waves that hit the mold. This caused the entire surface of the mold to ripple as the wave energy moved under the mold. It was extremely disconcerting and I became increasingly skeptical that a slab could be poured then set and float on this wiggle mess. Adding to the drama two workmen had the exclusive duty of bailing water from the edge beam as water washed over the tiny free board on the windward side, CRIKEY.

The day of the first base pour was initially calm and wave free and I got on site to find about 15% of the mold was covered and 20 to 30 workers hard at it. One diesel rotary mixer was used and the mix was carried to the mold using a traditional pan carried on the head. I was shocked to see the first pan emptied in a giant soupy splat with the consistence of heavy paint or soup. Water content was WAY WAY high in the .7 range. It was then patted into shape with a small pointing trowel and smoothed over a little with a wood float.

I had am animated discussion with the senior fella and explained again the principles of the FC mix and the critical mature of water content to the permeability of the finished work. I was assured the water content was as they have always done and would be fine. I pressed the matter several times until finally screaming like a mad man that the WC must be addressed. I went to the mixer for the next batch and added the water to about .5 range and when dumped from the mixer the head pan fellas looked at it like it was going to bite them. The mix was carried to the mold and the finishers just poked it a couple of times and then down tools walked away. Work stoppage

In the US the chain of command on site is simple, project manager- superintendent - labor foreman -  journeyman - laborious. All instructions are complied with or your toast. Not so in India, endless debate on all matters by all parties and almost never a firm resolution of anything, so after 20 minuets work re commenced but only after a good bucket of water was added to the mix. On the 6Th batch and after demonstrating how to deal with and place a proper stiff mix we went to lunch, lunch will happen in India regardless of the crisis or schedule and upon our return the mix was back to soup. LOTS MORE SCREAMING

On the afternoon of the next day the wind kicked up a little and the now curing 2 inch thick "slab" was rippling just as it had when just plywood, millions of cracks, millions. Small cracks , big cracks. All from the direction of the waves, not even kinda waterproof and not FC let alone LFC. I was assured the second slab with a proper mix would cure all the wiggling. Lots of small rod and endless wire tying for the next 5 days , all a complete waste of time, and then another sloppy pour, still rippling , still cracking, still denial. STILL SCREAMING

The side walls of Frankenstein monster are pre cast 2x2 M FC panels and to my horror they are all being erected on the windward corner and buy the time I show up 8 have been placed, the corner of the float  is deflecting six inches down into the lake so the free board is now ZERO. I make a frantic call to our leader Ronny and after much grumpy conversation with the foreman it is agreed to place the balance panels evenly around the perimeter going forward and that a man would be on hand 24h to pump out the deflecting corner.

The man goes home at 6 am the next morning the platform sinks to the bottom of the lake at 7.15 AM just over an hour later!

Chapter 2 of what I did on my summer vacation coming soon. i will try and post some pictures of all this as well.

Brad

Logged
Paul Sarnstrom
Global Moderator
Sr. Member
*****
Posts: 386



WWW
« Reply #1 on: September 12, 2016, 12:54:08 PM »

Hello Brad,

Well, it sounds like you had quite the adventure! I'm sure it was also challenging to live in India for that amount of time.

That is a huge FC project and I am impressed that a project of this scope is being done largely with hand labor. It just goes to show what can be done with relatively simple tools and techniques.

"Martin had devised a brilliant but radical floating mold upon which to build the mother mold for the floating hotel rooms and the same process was to be used for the much larger MP's for the solar project. Ply sheets are laid over a waterproof membrane with a wood perimeter beam of 2x12's. Some minor framing connected this all together under the ply so that the top side was flat ready to pour the bottom slab of the MP. The base would be poured in two lifts and a complex pattern of 2x2" mesh and small rod reinforced the whole thing as lath is not available locally. This process was closer to traditional FC than LFC but Martin and Colin were working with what they had."

So, the reinforcement consisted of 2"x2" mesh and small reinforcing rod. Is the 2" mesh comparable to a 'hardware cloth' type of mesh? Do you know what gauge wire the mesh is? What is the diameter of the reinforcing rod. I'm guess 6mm, roughly equivalent to our 1/4" rod. was the rod smooth or did it have some indents, ribs or other texturing to better pullout strength? Regarding number of layers of mesh - You stated this was poured in two lifts. How many layers of mesh and bars in each layer. I realize some of this may be proprietary information and I'm not sure what precisely you can state however any detailed information is most welcome.

I find the inability or refusal of the workers to carry out simple and straightforward instructions regarding the water/cement ratio to be ridiculous. I have heard of this with concrete projects in India and engineers bemoaning the fact that too much water was consistently added so the mix was easier for the worker to pour from a wheelbarrow. It must have been especially frustrating for you attempting to manage this project.

Wow man, I can't wait for the next part of the story and maybe some photos. Thanks so much for sharing this with the FC Forum.

Paul
Logged

Paul Sarnstrom
philb
Sr. Member
****
Posts: 214


« Reply #2 on: October 03, 2016, 06:14:07 PM »

I have seen the same runny mud used on the Indian temple in Oklahoma City. All kinds of elaborate statues were crumbling and cracking even with an elastomeric coating. They seem to love runny mud mixed with hands used instead of measuring cups and scales. I have the idea they may be mixing more water to accommodate heat drying out the mix before it can set up.
« Last Edit: October 03, 2016, 06:35:52 PM by philb » Logged
upston
Full Member
***
Posts: 97


« Reply #3 on: October 05, 2016, 07:10:29 PM »


Hi All,

Thanks to Paul and Phil for the comments. The mesh is 2x2 welded wire and was delivered rolls for MP2 and then in flat sheets 2x5 meters. Not sure the G. The base of the platforms had four layers the side walls had three the internal bulkheads had two.

So when we left our story MP1 had sunk into the lake and the work forman and DESIGNER of this mess was hiding in his shanty hut asking how this could happen. How could it not. I watched the interview of the fellow who went home at 6am from his pump duty and he was totally without guilt or shame and it was very clear he was off duty and was just following instructions. he was the only local worker and ended up the most willing and able chap on the site.

So three months of work was at the bottom of the lake and the rains would start mid June just 10 weeks away. A rice field was identified several miles around the lake road that offered us a large flat area of dry land that would be flooded shortly after the monsoon set in so they relocated and work on the first of three new MP was begun. These MP would be poured on the field and then the flood waters would float them off , at least that was the idea. The land was fine graded by hand and a very bad compaction job ensued. I was concerned that only the top inch or two was compacted and lots more screaming was necessary to have the need for decent compaction sink in. They used the Jeep , back and forth a billion times and after a day or so it was firm under foot, kinda sorta.

A large plastic billboard cover was used as the slab liner and a perimeter form was pinned into the soil the same height as the finished slab, approx. 2 inches which allowed the four layers of mesh to be tight together per good FC practise. Two of the four perimeter wire sections were upturned four inches so the vertical walls could have a mechanical, reinforcement connection to the slab as well as the concrete joint itself. All four layers of WW ware embedded in mix in offset layers working off one side keeping a wet edge as each 2 meter row was laid. Two mixers were used and the work progressed well enough that even with a 10 am start and the customary lunch we were done just before dusk. The floating MP took two full days two layers of WW each day and a total thickness of approx. 4 inches was achieved so the new MP used 50% of the cement and sand with the same reinforcing as MP1

The mix was entrained by workers wearing rubber boots stomping the mostly proper mix into the wire, four men in a line stepping up and down. Many workers were tried till I found four that would stomp as needed. Most would stand on one foot and poke about with the other to zero effect but after several crew changes we had our boys. The big hold up during the pour was the finishers and the mesh laying. The mixing had to be haulted several times waiting for the trowels to catch up. Wire would not be properly covered and extra mix was added and finished only to be re exposed. This problem was resolved by placing rocks in strategic locations and eventually systematically as they proceded down the rows.

Re: wetting / curing the slab commenced the same day about 2 pm and continued for several days on and off, this was inconsistent at best and some small surface cracking was evident but nothing like the floating platform which would not have been water tight at all. MP 2 slab was an order of magnitude improvement as far as mix degsin and speed was concerned but there was still plenty of room for improvement.

Next job was slab for MP3 and setting sidewalls on MP2, and finding something to eat that would stay in for more than a few minutes.

Brad

« Last Edit: October 06, 2016, 08:29:44 AM by Paul Sarnstrom » Logged
Paul Sarnstrom
Global Moderator
Sr. Member
*****
Posts: 386



WWW
« Reply #4 on: October 06, 2016, 08:42:53 AM »

Hi Brad,

Wow! Thanks for the second installment of your FC adventures in India. Using rocks or any other readily available weights to hold mesh reinforcement sections down is very useful in building horizontal, FC slabs. As you are aware even meshes that are supplied in flat sheets have minor bends and bumps in them that prevent the layers from being in close contact.

I first encountered this when Martin Iorns was teaching a class on Laminated Ferrocement and seemingly flat sheets of expanded metal lath had occasional small bends or kinks that tended to pop up here and there. Martin said to improvise and grab whatever weights were available to hold the mesh flat while curing. Using a small piece of plastic sheet between the weight and mortar allows easy removal of the weight after the initial set has taken place. We used concrete blocks, bricks, rocks and 2"x4"s, whatever was handy to weigh down the high spots. Simple and effective.

Thanks again Brad and I look forward to the next part of your FC adventure.

Paul
Logged

Paul Sarnstrom
crasch
Full Member
***
Posts: 23


« Reply #5 on: February 21, 2017, 02:56:01 PM »

Thanks for posting this story, Upston!  Would love to hear more about it.  How did it turn out? 
Logged
crasch
Full Member
***
Posts: 23


« Reply #6 on: February 21, 2017, 03:05:45 PM »

Anyone know how I can get in touch with Upston?  I'm a volunteer with The Seasteading Institute, assisting with the The Floating Island Project:

https://www.seasteading.org/floating-city-project/

I want to reach him to inquire about hiring him to help with a sub-project related to the FIP.  However, the forum software gives me an error when I click on his name to message him directly.    Thanks in advance for any assistance!





Logged
upston
Full Member
***
Posts: 97


« Reply #7 on: February 22, 2017, 11:15:54 AM »

Hi Crasch

My e mail is bradfordsimms@gmail.com, I have been a big fan of the Seasteader project and would love to help.

I will do a final post on the India project soon but bottom line " It floated"

Brad
Logged
crasch
Full Member
***
Posts: 23


« Reply #8 on: February 22, 2017, 09:25:25 PM »

Thank you, Brad!  Writing you privately.
Logged
upston
Full Member
***
Posts: 97


« Reply #9 on: February 28, 2017, 08:37:36 AM »

Hi All'

This is the third and last installment on the floating solar project. I recently received a photo of the build site after the flood. All three mother platforms are now floating as intended in the dam basin. Given the very sloppy construction  , bad sand,  wet mix , lack of constant curing and total lack of supervision by the upper management it's a minor miracle it went so well. It is a great example of the forgiveness of the FC/ LFC construction method.

I came bask to the US after six weeks , it seemed a very long time living through it but looking back now several months some of the horrors have faded from memory. I was unable to fully impart good construction practises but some improvements were achieved. I was never paid the bulk of the promised fee for my time despite repeated assurances. The CEO of the company is a charming fellow but lacked the strength to lead his team to produce a quality product.

I am not sure if the 17 platforms were ever built to complete the project, certainly they were not within the contract period of November 20016. In spite of the difficulties and lack of payment I am proud of what was accomplished  and while I wont be going back I am glad I took the trip.

Brad
Logged
Pages: [1] Print 
Ferrocement Educational Forum  |  Ferrocement Discussions  |  Projects  |  Topic: Floating solar array in India « previous next »
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.13 | SMF © 2006-2008, Simple Machines LLC Valid XHTML 1.0! Valid CSS!