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New Basement Products.
New products that could be used in basement construction already available in the USA, but not in the UK yet.
I would like to blow my own trumpet first. Over the years I have been quite influential.
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I was the first to add an upstand to my retaining walls that extended to above outside ground level and prevented a horizontal ingress of water over the retaining wall. This is quite common now.
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BS8102 was re-written and re-issued on March 31st 2022. The new Standard is exactly what I have been arguing for on this web site for years. The new Standard requires continuous waterproofing to 150mm above outside ground level. This seems to be a change due to my example.
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Supervision of water resistant reinforced concrete works is highly recommended in the new Standard. I have been saying for years that supervision is the most essential element for success.
I made another trip to Las Vegas to visit the World of Concrete Show during January 2023.
There was even some gambling at the show. A large stand rewarded you with tokens if you spoke to anyone manning the stand. You used the tokens in a one-armed-bandit slot machine to win pens, hats, T shirts and so on. I won the jackpot. A cement mixer.
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They do things a lot differently in the US and Canada.
They use far more cement than we do. For instance, why build a roundabout when you can build miles of concrete road overhead?
Another major difference is local authorities can have their own building codes. Many areas only require a shallow trench for one line of thin starter bars.
But, otherwise, there is no wall steel.
I was telling a structural engineer at the show how much wall steel I require to prevent cracking. He fully understood but he said USA and Canada clients won't pay for it.
He went on to say that where a local building code allows as little steel as shown in this sketch, it also requires that the backfill must be free-draining shingle in geotextile filter membrane. But he says many contractors, including in areas of clay, just put back what they dug out.
He believes that where clay sat by the side of the excavation for the summer, where it dried and shrank before it was put back, it would be re-wetted later (probably when the snow thaws), expand, heave and push and crack the retaining wall.
But he said basements are quickly dry lined with studwork so that the occupant never realises their basement is in the early stages of collapse till long after the contractor couldn't be found to put anything right.
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Just because they now use something in the USA, it might not be good.
But my selection are products that might be useful.
One. Fibreglass concrete reinforcement.
I first used threaded rods of Fibre Reinforced Plastic, (fibre glass to you and me) in 2012. I use them to replace the steel threaded rods in a plastic tube that are commonly used in UK wall formwork because the holes are a source of leaks. My rods are cut off and remain so that cause of leaks is avoided.
Years ago, I discussed with a few UK engineers using them as rebar, but without a UK code they wouldn't entertain them.
However, over the past two years the USA has adopted new codes for FRP concrete reinforcement and half a dozen suppliers at the show were promoting their range.
One of the US FRP suppliers had a favourite story.
He loaded a trailer with FRP rebar and booked a truck to hitch it up and deliver it.
The driver arrived and drove off again saying it was many times overweight for the road.
But his FRP is, he said, less than 25% the weight of steel and actually the trailer was several tonnes under the maximum weight allowed.
This is the photo he showed me on his phone.
This supplier was telling me that they are more efficient making the glass strands and the resin themselves in the USA. I believe he told me that the energy required is only 15% the energy required to make steel reinforcement.
And another. It was late on the third and last day.
Another exhibitor's literature.
I mentioned to one that his rods were smooth, almost like a laquer. He said what they did to make them smooth was their secret and lacquer would cost too much.
My rods can leave little splinters in your hands when you pick a load up. but one at a time they are OK. Wear gloves when you pick a load up.
By some coincidence, at LAS airport the next day, a man was wearing a World Of Concrete Show top. I struck up a conversation and his firm fixes steel. I asked if he had seen the FRP. He said they had used it. His men might carry 30 bars instead of 6 which saves time but on someone's shoulder they bounce about and rub against each other and the surface roughens up. He said after carrying long FRP bars all day a man's shoulder is raw from the abrasiveness caused by the surface getting rougher as they walk along.
Two. A. Make Granite.
These people were explaining that you mix the sack and the bottle, these proportions will be correct, then you add and mix in aggregate.
You will create what they kept describing as something very granite-like.
Your aggregate might be crushed recycled glass, limestone, crushed concrete and brick,
Absolutely no water or cement is involved and the result would be strong and waterproof, they were sure.
As a group and with partners they are experimenting and researching to learn more. They seem to say that this material is best suited to 3D printing on their website. Geopolymer International website.
At the bottom of their homepage they have a warning not to mix up what they are doing with any company that makes a concrete from GGBS and alkali (sodium hydroxide).
On the stand, I mentioned the D B Group (that includes Pudlo and Cemfree) who told me years ago they planned to buy all the GGBS in India. The people I was talking to were aghast. They said GGBS and alkali is very dangerous. Not just while it is setting but for a long time. They spoke about painting any concrete before it might be safe. I note that on the DB Group website they promote laying bricks and the bricklayer is very well wrapped up, which is rare for a bricklayer. they are the first to wear shorts and take their shirt off.
Two. B. Building products from plastic waste.
From the Terratico web site.
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Imagine over 1 million Statues of Liberty. Now imagine they are all built from plastic waste. That's how much of plastic waste we produce on the planet yearly. And the number is still growing. We didn't want to turn the world into a big plastic monument. That's why we started Terratico.
100 thousand tons of plastic waste can disappear every year
Terratico means change. We have turned plastic waste into a highly aesthetic building material. And "We change the world" is no longer just a phrase. Join us and help increase that number!
Terraticotm uses crushed plastic waste instead of gravel in concrete or crushed marble in terrazzo.
"
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Three. Recycled, disposable plastic roof deck superstructure.
The panels stand on plastic tubes. You pour the concrete up to 300mm thick. You, apparently, send the plastic tubes off to be recycled into something else. The panels can stay in place.
disposable formwork.
I will look into using boards made of recycled plastic waste instead of timber in my formwork, when I get the opportunity.
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For a fixed fee of £199 I will answer all your questions by email. More details here.
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