Different Perspective on the Concrete Issues in Haiti

I posted that before I got the email to register.

I do not really mean to spray water on your idea. It certainly has some merit.

What would happen if a structure of such construction were to burn?

It would be a disaster, toxic fumes, bad stuff everywhere.

But, and this but is imporant, everywhere this concept is needed at this point in time already has a tradition of plastering inside and outside of walls.

There are as many different versions of plasters as there are cultures. They all work, some better than others.

The fire hazard is a reality. It is also a reality in strawbale construction, conventional wood construction, and just about any other kind of housing construction you can come up with.

Hi Harvey,

Looks like a great idea. Would you cover the plastic blocks with something after they are installed?

The reason I ask, is that I can imagine two potential problems.

1) Many plastics will decompose in sunlight, becoming weak and brittle. This would affect the outer surface only, but over time could loosen the compaction of the blocks within the wire and compromise the entire structure.

2) With the outer surface of the blocks exposed to the elements, I could see a real risk of water collecting within the blocks and providing a breeding ground for insects, fungus, bacteria, etc.

I like the earth bag idea. Another thing I think would be a good idea, although it wouldn't help in the near term, would be for them to start propagating and massively planting bamboo, which grows fast, and always makes a good building material.

Plaster.

One of the interesting things about this concept is where it is needed there is already a tradition of plaster. Plastic blocks replace ugly stuff they've been using for years and have traditionally covered with plaster some kind of plaster.

http://recycledplasticblockhouses.com/recycled-plastic-block-wall-drawing/

I hadn't seen your previous reply when I posted. My brother lives in a hay bail house and loves it. Like you said, plaster/stucco inside and out.

Here's a proper link for the sitehttp://recycledplasticblockhouses.com/

We could have that discussion about concrete, but it isn't relevant to your situation

apples & oranges there Harvey

I'm not sure you can make foundations from plastic blocks

this is concept reminds me of CEB [compressed earth block]

have you contacted any colleges or universities about testing?

you could use post tensioning

there are going to be seismic issues to deal with... send me a PM if you want, a few more details might help a bit... I have a couple of pdfs I'll send to anyone who is interested in CEB

Here are some CEB Things

Quick Facts

Soil Composition

Press Design

Thanks for correcting the link.

As you can see the engineered drawing shows a concrete footer/foundation. The walls are covered with a plaster inside and out. The rebar is installed outside the blocks which is an accepted method. It also adds strength to the structure.

Now think for a minute about the pressure that's removed from the concrete process if portland cement isn't needed for making CMU's. Consider the cement not being needed to make mortar for joints. One of the biggest pressures on concrete construction is the cost of the cement. That cost is a factor in poor concrete because there is an incentive to thin out the mix.

It is relevant, it's about about making better concrete by subsituting another product whenever possible to pull the pressure off of concrete materials.

CEB's are great. They just cost more if there's plenty of trash plastic around to use in recycled plastic blocks. They are also more labor intensive than recycled plastic blocks. The don't provide the R values of recycled plastic blocks. It also takes more CEB's to do a wall than it does recycled plastic blocks. It takes four 4" X 8" CEB's to cover one square foot of wall, one recycled plastic block.

what happens when you throw scrap plastic in a cardboard bailer?

You get bales of plastic. They do it all the time at the recycling centers. Approximately fifteen hundred pound bales, last time I checked if the #1, #2, or #3 resin plastics bale was worth $420.00 per ton to the recycler. Those bales are processed by a company that cleans, shreds, and then sells the plastics as material for making new plastics, fifty to sixty cents per pound right now.

The idea is to sort out the desirable plastics that are worth more for recycling than they could ever be worth in a wall. That is used as income to offset the cost of the block making operation.

then it's not a big leap to make a proper hydraulic press automated bailer. the dimensional consistency will have to be pretty good

proper dies for interlocking blocks...

built in loops for attaching the stucco wire

what kind of mortar?

you still need a foundation, which will be made from concrete & rebar

so what kind of calculations are you looking for?

We are addressing this issue because the concrete building materials failed, how would a network of wires (interconnecting every block) hold up in earthquakes? I would suspect that the wires at the base of the wall would fail due to the increased strain based on the height of the wall. How would we go about validating this network?

I wouild suggest you consider the difference between how a chainlink fence survives an earthquake versus a CMU wall.

Keep in mind the blocks weight between seven and ten pounds, compare that to the same sized concrete block of between twenty five and sixty pounds. Eight foot wall would have a hundred pounds or less of wall weight on a recycled plastic bottom course block versus five to six hundred pounds on a concrete bottom course block.

Keep in mind how this came about. I was challenged by a Kenyan architect to come up with a building product that could be made with all the plastic trash that is everywhere. That was about ten weeks ago. We have a prototype machine that is manual that works. The blocks are strong, a ten pound block only depressed three quarters of an inch when I placed thirty four hundred pounds of truck on it.

Check out the videos

http://recycledplasticblockhouses.com/bob-put-the-original-videos-up-on-youtube-today/

That i understand (mostly), i like the idea because it is making best use of "garbage," which is readily available when traditional resources are either scarce or of unreliable quality.

But a failure at the base will result in a chain reaction of failures up the wall. Perhaps, could other traditional western construction elements be integrated into the structure. As you mentioned the chainlink, periodic rigid members joined to the footing.

What they do in earthquake prone Cyprus is create a heavily re-enforced concrete framework. Then they fill in between the posts with tile, bricks, stone, straw re-enforced sun baked bricks or whatever. And of course they plaster over the bricks. Those bricks could be burnt tiles (traditional), cinva rammed bricks, or trash bales, or even bottles (to let in light in lieu of expensive and insecure windows)

I watched them setup the forms, and wire the re-bar in one week, and pour a subdivision in one day. Then it took another two years to infill all the gaps and holes, but that was hand work done mostly by either the home owner or by the community.

If you have lots and lots of people, then hand ramming would work. But its hot and sweaty work. But it just uses dirt. They DO have dirt in Haiti don't they? Oh sure, you can mix it with 1 in 20 parts cement if you have it, but thats not absolutely necessary.

Foundations are going to be your major problem. Walls as you can see, are easy.

Just a thought. Why not shred the plastic. This shredded plastic can then be used to infill sheeting like blown insulation. It seems to me it would be quicker and less labour intensive than blocks.

or

If a mold(s) was available to the installers or at a plant in Haiti they could receive bailed plastic trash (if it is valuable to offshore collectors, it may be hard to get for Haitians without someone paying the price). The bailed trash then could support some employment in Haiti to process the plastic into shredded insulation, or could actually be used to build hollow hardened plastic blocks that could be filled with the shredded or confettied plastic. A system similar to Bloklok in a prior post could be used. A fireproofed coating may still be required. I think this would work out for the Haitians; particularly, if the blocks are built in Haiti. Otherwise, I suspect the Haitians would think we are dumping garbage on them and may be faced with another outrage like the cholera problem. If they are actually making the blocks and tooled properly, I suspect they will show new pride. Now we need to build a facility to centralize the receiving, shredding, and re-forming into building blocks. Once the housing demand in Haiti is met, they would have a plant capable of making a product for international demand. They ought to welcome any enterprise that can help them in the longer run.

I think your idea of compressing plastic is admirable. It does present some issues with wire corrosion and cosmetic appearance. These can likely be overcome in a more sophisticated society but may be problematic in Haiti.

The block isn't designed to compete with conventional construction be it stick, SIP, etc.

Every fault you mention applies to all sustainable building systems. Earth bag has to be covered with a plaster to maintain the integrity of the bags. Strawbale has to be protected from the weather be cause moisture causes rot. Old tire construciton isn't something that will be accepted in hokeyville because of aesthetics.

The trash is already there in Haiti. It is a problem. Clean and ground into flakes numbers 1, 2, and 3 plastics go for forty to seventy cents per pound right now on the international market. But that price is like quoting retail steel dollars to the rebar the Haitians are salvaging out of the ruins. They are probably getting a penny a pound for the rebar at the recycler. Bulk plastic will probably get them about the same per pound and is a lot more difficult to collect.

As for the bulk plastic being shipped to Haiti. Two months ago when I was at the recycler picking up raw material to make the blocks the same stuff, 3 through 7, was going for $150.00 a ton for the recycler. It would cost at least four times that amount to get it to Haiti. (still a bargain when you think an average house will require about three thousand pounds of plastic trash made into blocks).

Why not just use wood framed buildings covered in stucco. Haiti is not all that far from the US to ship 2x8s and such (probably not any farther from the lumber industry than Las Vegas, and if you have ever seen all the rough framed buildings just standing out in that desert after construction was shut down). Wood framed building perform exceptionally well in seismic zones. Obviously for buildings over 2 stories other approachs would be needed, but most homes and apartments are 2 stories or less.

RCE-

The problem with wood-framed houses in the tropics is humidity and termites. Wood would last less than a year, unless one uses something a bit more durable than standard building lumber in the US.

So they don't build wood framed houses in South Florida? (not siding, but framing)

I might pose the question what do they do differently in the Dominican Republic, since it is closer than San Francisco was to the loma prieta quake center and lies along the same fault system unlike SF. You know they felt it in the Dominican Republic. Do they regulating building practices better there? Better engineering design? Better restrictions on where and how people can build?

Maybe the problem really isn't a materials issue as much a issue of regulation and enforcement.

There is work on having a building code in Haiti

Yes they have a working government in DR & code enforcement of some sort

we are trying to craft technical solutions to political problems in Haiti

& on some level any thing is better than standing in muck with a tarp for a house

we should consider this project on it's own merit(s)

Of course an issue becomes though, if someone throws a tarp up to protect themselves from the weather, versus you build/design them a structure to reside in that fails. If the tarp structure they threw up thems selves fails who is responsible. If the residence you built for them fails who is responsible, especially if it is an experimental and untried technology.

What happens when the wires holding the blocks together rusts? Will the blocks expand? If they expand is it in more than one dimension? Will the wall made of it collapse?
Will the blocks be used as support for structures above them?

I think you really need to know the answer to these questions.

Hi Guest,

I am saturated with all kinds of resistances from people like Haiti. They are poor, they don't have any money, any capable organization, and knowledgeable people to get out of their difficulties.

At the other side, we send money, we send people to help them, and do good things to local people. And finally, we discover that nothing get done after one year of effort.

1. If they don't like Portland Cement (We pay for it!) don't give them.

2. They want something their way, let them do it. They cannot make anything with nothing, isn't it? We have to do it our way, the good way!

3. What was done before? Be honest, it was misery and they want to return to that status.

We have to accept the fact that we invented practically everything in the world working for better or worst by us and they have to accept our proposal to rebuild their ravaged country.

It's the same everywhere. We try to help but they don't want, and still they are jealous about us and want to copy our standard of life.

Actually, we cannot talk with the chief of the country because they don't have a president or someone competent to talk with us, Gil.

What you are proposing is very similar to a product called Covintec, which is growing in popularity here in Panama, and which apparently has also been used extensively in Costa Rica. It is essentially styrofoam panels sandwiched between two grids of lightweight reinforcing wire mesh (two inch mesh, fairly light wire, although I don't know the exact gage), in 4 x 8 foot panels. Usually, a concrete frame is built, and the panels installed between the concrete columns, and stucco applied over the wire mesh, inside and outside. The styrofoam panels are approximately 2 inches thick. Conduit, water lines, etc. are inserted into the wall prior to plastering by burning channels in the styrofoam as required. Plaster is often applied by portable shotcrete-type concrete pumps. Cheap, easy, quick. Both Costa Rica and Panama have occasional earthquakes (although not generally of the magnitude enjoyed by Haiti, Chile, Japan or California), with no apparent damage to these structures. Although there are certain climatic regions in Panama and Costa Rica where R value may be of significance, in most of the tropics this is of very little concern- structures are usually built with significant roof overhangs to shade the exterior walls, resulting in minimal heat absorption. Most poor folk are not going to be enjoying air conditioning. Ventilation is most important...

Have you given any thought to different form factor for your blocks? Blocks may be cheaper than panels from the fabrication standpoint. I do not believe one should build multi-story dwellings in a community where building codes are poorly enforced, if they exist at all. Most of the people in need of housing in Haiti are used to living in owner-constructed single family shacks built from scrapped building materials scrounged from building or demolition sites. Your plastic blocks potentially represent a step up in availability of materials, and an improvement in cost.

Unfortunately, much of the mismanagement of the relief efforts in Haiti are in the relief agencies, not the Haitian community itself. Very little of the relief money has actually reached Haiti, and Haiti has been flooded with vultures more interested in making a profit at others' expense than actually accomplishing something worthwhile. If you want to see your idea approved in Haiti, you need to start greasing palms at the UN and FEMA....

GA, good post with good ideas and thought. Covintec does sound like a better and quicker idea with a proven track record. How do these buildings fare in hurricane season?

Another problem in Haiti, (besides the poor leadership, lack of regulation, lack of skilled population, etc) is simply cleaning up the aftermath of the past earthquake. Guest has at least bought the problems in Haiti back to the forefront.

We don't have hurricanes in Panama and Costa Rica- but they do in Mexico, where this stuff is manufactured. I have no information about hurricane effects...

I don't see the commonalities in your link beyond plastered walls.

Here's the biggest difference and I think you touched on it quite nicely, thank you.

The only thing that needs to be imported into Haiti that isn't already there to build this kind of structrure is the concept and maybe some training.

The plans and photos are online and available for free. There should be welding shops capable of making the machines. There should also be local sources for the wire, samething with the rebar.

Consider the funds used to build a shelter, local dollars multiplying the way local commerce does local dollar multiplying. Haitian helping Haitians use the cheapest materials at hand to build shelters, permanent shelters.

The plastics can be expected to survive for three hundred to thousands of years in the landscape. It has to be more inside a plastered wall. Galvanized twelve gauge wire is another thing though. I've read six years in the elements to hundreds of years inside of walls.

One of the problems is some people assume poverty suggests ignorance. In America we have living proof that isn't true. It wasn't the poor that caused the housing crisis or the Wall Street Meltdown.

Haitians are a clever people. I have no doubt that if the warm up to my idea they will show us a thing or two about how to do the most with the least and make it attractive doing it.

Now a few obvious engineering concerns about pressed plastic blocks (not chemically or thermally bonded. What is the stress strain relationship for these blocks as this would limit how high and how much load capacity as a bearing structure. I would suspect that they are not as strong as concrete and much more strain would develop. Also the strain would translate more directly into lateral strains unless properly confined, thus causing substantial deformation and possibly substantial creep. How are they confined to maintain their proper shape against deformation? Also, what is the homogeneity of the stress strain relationship? differential strain across a bearing support column structure of any type is very bad. It would lead to bulging or bending walls under load that would then collapse as they loading became asymetric. How do you bond the blocks together to avoid lateral movement, would friction alone be sufficient? Proper CMU has reinforcement longitudinally and vertically to resist movement. Wouldn't it be better just to precast structures and ship them. then you have a relatively control performance structural component that just has to be properly assembled. Then you could use something like thermally bonded plastic bricks, or even solid plstic structures

The blocks are compressed longitudally so the lateral pressures are minimal because we're not dealing with a liquids would be my guess.

One of the answers I was hoping to find someone to help me find an answer to was the amount of pressure I'm applying with the ACME threaded rod. It's a one inch rod with four tpi. I only need a little extra leverage, old man itis showing up at 62, for the last couple of inches with a nine to ten pound block. My guess would be somewhere between 100 and 150 foot pounds of torque at this point. Guesstimate based upon old working on car days.

I haven't used a torque wrench because of two variables I'm dealing with right now. The first one is the weight is a constant, one pound into the mold, one pound out. But the foot pounds to compress varies with the weight. The second variable involves the weight versus strength. If you look at the videos you can see that I don't have a lab with equipment to measure that kind of stuff.

My initial concern was that the concept was viable. I have no doubts now after messing around with the blocks I've made.

That's why I came here to where the engineers are.

I need help to figure out the number of pounds a block needs to weigh to support an eight foot high wall. I know a ten pound block can support thirty four hundred pounds with only 3/4" compression. But if a six pound block will support a wall then we get ten instead of six blocks out of sixty pounds of trash plastic. That's what engineering will give you that guesstimating can't.

Another question I have is about shapes. I have to wonder if a trapezoid or parallelogram shape would be stronger laterally than a rectangular one? I think someone smarter than me might see an advantage because there's more contact area. The downside of that of course would be ends etc. I've already figured out how to make inserts into the press that would accomodate the different shapes if they offer advantages.

I've read that Haiti doesn't have much clay in their soils. That makes the CEB's a little less attractive I know. But it also offers an advantage for the recycled plastic block. Without substantial amounts of clay in the soil you don't get so much of the heave or shift between wet and dry periods. That suggests foundations needs are less than you would require in a soil with an abundance of clay. It also makes an idea I had for the floor of the recycled glass block more attractive.

What I had in mind was laying down of the bottom course of blocks. These blocks would have rebar driven into the ground at doorways, corners, and at specified locations in the walls. Short pieces of rebar could also be driven into the ground between the blocks and tied to the blocks with wire ties. Then rebar and wire could be criss crossed across the floor of the structure. They would be wire tied at each intersection. Dirt would be brought in and tamped down to make a dirt floor.

This wouldn't be applicable in a lot of places like hillsides etc. Most of us have seen dirt floored buildings that have survived many years without this much support. If the difference between having permanent housing and staying in temporary shelters is the cost of a properly engineered concrete floor it might be worth considering those most affected having a say about it.

One of the other things I've wanted to find someone much smarter than myself to figure out is the R values of the plastic block. We know that steel framing cuts the R value of insulation by half. CMU's and CEB's offer poor R value unless you go thick enough to get the flywheel effect. The lighter the weight is of a plastic block the more open space is in the block That open space is divided into chambers by the process of making the block. I think that suggests a recycled plastic block would have a very good R value with plastered walls.

I appreciate your patience and eye/ear. One of the things that I have learned to live with is I'm not as socially adept as most folks. In fact when I saw the movie on HBO "Temple Grandin" I finally realized it was okay being different. If you've seen the movie and you noticed she could be rude without meaning to be mean, well, that's me most of the time. I get hung up on ideas the rest of the world falls out of sight.

GA and good sites.

I still not convinced a plastic trash block would even be accepted in Haiti. Years ago I remember a company trying to sell older technology to the Chinese and they rejected it resoundingly even though it was low cost. The Chinese were only interested in state of the art technology.

I think if Haitians are to move forward in the long run, we should provide a stable form of housing. Covintec as recommended in post 24 seems superior to trash blocks. It can still used recycled plastic, is low enough technology that can be handled by low educated labour forces, it can be multi storied to take up less footprint in a country with limited space, looks somewhat earthquake proofed in that large chunks of unstable concrete will not fall on your head, and it is proven off the table technology. Right now clean-up of the existing mess needs to be sped up.

No offense take Yusef. I have many friends who are engineers. Lord bless them LOL.

I don't expect an engineer to sign off on anything. But there are some engineers that like a challenge and are interested in more in making a difference than making a point. Those are the ones I'm looking for.

One of the interesting commonalities of your links is the plastic is processed before being used. Those ideas had potential before the demand for plastic for recycling. Now there is a demand for processed plastic for raw material for new plastic the concepts of using it because it was free is no longer viable.

Look up Byfusion. Peter is a genius. But do a little mental math and I believe you will agree with me that they missed the moment.

Sadly if I wait on the engineers and conventional wisdom to validate my concept I will too have missed the moment.

I have a history with engineers. http://www.millerwelds.com/resources/communities/mboard/showthread.php?20118-Curving-a-Piece-of-Pipe-for-a-Corral-Project/page4&highlight=double+helix

In there you will find out the difference between theory and practice.

http://www.millerwelds.com/resources/communities/mboard/attachment.php?attachmentid=20639&d=1262454530

A couple of things I observed as I quickly perused the statement to address. 1. Foundation design in non-cohesive soils can be more substantial in seismic zones than in cohesive soils, i.e. liquifaction. 2. you do not drive structural reinforcement directly into soil without special corrosion protection, you will need to consider somethin other than just driving rebar into the ground (especially in weahtered soils that can be corrosive). 3. It doesn't matter if it is solid or liquid whenever you apply a load to any material you get some compressive strain in the direction of the load, and a compensatory negative of that strain in the lateral directions, the material has a certain amount of resistance to that transferred strain. So far I haven't seen any test results to indicate anything about the strength and stress-strain characteristic of this proposed material. Bear in mind the limitations to things like brick as a structural building material come from the strength of brick, eventually stack enough bricks on top and the underlying bricks will fail, and the walls then fall down. If an experimental material fails in a impoverished country being rebuilt after disaster (or even louisiana) that is just made from garbage from another country, how do you think that would play out in the news in say tens years when some failures begin to occur.

Tell me though...have you ever considered the Cinva Ram? At the risk of sounding negative, I have always found that trying to solve two issues with one amazing trick to result in failure to solve both issues. For instance, garbage blocks...what holds them together? rusty wire mesh? What happens when the mesh rusts out? Do you get piles of garbage? Waste that should have been shredded and pelletized, and now it washes out into the bay to become dangerous food for the birds and fishes?

A cinva ram uses dirt. You get a better brick with a little cement, but gazillions of successful blocks have been made without the portland cement. If you have a problem getting the cement then cinva rams are, like, perfect!

Also, there was a time when blocks were made from sun dried clayey mud with chopped straw inside. But of course, you DO have to protect such walls from the driving rain. Absolutely stunning for use in interior walls though.

People always have "issues" with rammed earth. I don't know why. You can ram with zero cement to as much as 10 percent cement. (concrete is about 30 percent). The result is always a good looking, long lasting building.

There has been a long tradition of using "garbage" in rammed earth. Dennis Weaver built his house with hand rammed tires. The previous link shows how few tools you really need to do this. I found this to be a really good use for old tires. Or you can use machines.

I urge you to check out all these links and see what can be done without coming up with new and unproven technologies. In my native Prince Edward Island, we have been known to make houses out of old bottles.

The Cinva Ram was an idea I had suggested many months ago, back in the "Container Housing" thread, and that is what Garthh's "CEB" ("Compressed Earth Block") suggestion refers to. The Cinva Ram actually originated in Colombia, South America, back in the 1950's, and the idea is quite popular in Africa. I know that there have been adobe structures that have lasted for centuries with proper care, but, due to the compaction, it would seem that CEB would be more durable. CEB and rammed earth give very similar results, but rammed earth requires a lot of forming, which requires materials that may not be readily available.

This does not address the seismic issue that was the reason in part for proposing the recycled plastic in preference to concrete. Earth blocks are compressive strength materials which will have a similar failure mode as concrete block, just substantially weaker conhesive strength per pound of material than concrete. And as we all know, we discount tensile strength for concrete materials in design as it is considered to weak. also, there is some consideration for binding materials in the tropical islands there, as the soils tend to be highly weathered and aged, clay minerals are not as common as they are in other environments.

Yeah, whatever. The question gets asked a lot. And answered a lot.

Seems that earthern buildings don't fall down in earthquakes. Well, not as much as say, stone buildings. Well, they do, when they are made really cheaply. Malawi for instance, had some bad results. They don't like cheap walls. They want "some" cement in the mix.

earthquake resistance of rammed earth

Code...NZ......Code California.....Fred Webster's thesis on seismic resistance.IS

IS 13828:1993 earth building code India with reference to earthquakes.

Problem of building rammed earth buildings in eathquake zones has been solved. Problem of creating shelter has not been solved.

Blocks from trash will be impossible to determine engineering data from block to block, and IF concrete block or rammed block structures collapse due to seismic activity, so will trash block structures.

Excellent lnks...

Hi Warner,

You are absolutely right: "Excellent Inks..." Yes, all these are words on the screens and nothing is realized in Haiti.

My questions: Who decides "what to do" for the people of Haiti? Who decides about the "how to do" when the "what to do" is accepted?

Now, with the arrival of Duvalier, who will be the next presedent (80% chance of success), we should talk and negociate with him about the future of Haiti.

Good negociation, Gil.

So reinforced concrete columns and grade beams to reinforce the structure. Yes that would address exactly what i was discussing above. Of course you still need higher strength structural concrete and reinforcing steel or tensioning cables.

Yes. Perhaps an engineer should look into that.

In case anyone didn't catch it, Harvey was inspired to post by a thread I had started here

Any suggestions would be appreciated