07/10/2024
Celebrating Teachers' Day: Insights from WOli the Builder and Big Kay .
Questions and Answers Between WOli the Builder and Big Kay. Episode 107.
Big Kay:WOli, thank God I am able to see you again. I know how difficult it is to get you. Happy Teachers' Day to you, sir.
WOli: Thank you very much, Big Kay. A lot of people don’t even remember I am also a teacher in my own way.
Big Kay: With the many issues and abuse we're having with concrete, as most use materials in our building construction process, what are your thoughts on this?
WOli: As of now, concrete remains a high percentage of the materials we use in building different types of houses in Nigeria, and up till now, we don't have any alternatives. We're still depending on it unless we conduct more research to find materials to replace concrete.
My advice is that we should really improve our concrete since it's our major material, and we should have a lot of awareness programs for young people to understand concrete work better.
Big Kay: What precautions should you take when you're about to cast concrete on your site?
WOli: Thank you for the question. My answer will be three-fold:
1. Before you start your concrete work and after.
2. Get your materials.
3. Determine what to do.
Before you even think of starting your concrete, please understand the mix ratio. Ensure you have experience with mix ratios and how you can tweak the mix to achieve your desired results.
You should have experience with cube tests and how various materials affect your test results.
If you've not done anything about mix tests of concrete, please check online or consult concrete journals; many of students in higher institutions have engaged in that training.
The second stage is for you to know the types of materials you're using. Please, when you're working outside Lagos and Ogun, you may not get good sharp sand. So, you must know how to manipulate everything together to get the best results.
1. If you are not getting very good sharp sand, consider using stone dust. A good grade of coarse aggregate and the sand. The idea is for you to lower the quantity of sand and replace it with stone dust .
Note that only stone dust cannot provide the required strength because some particles are lacking in stone dust, so you need sharp sand and should think about adding a admixture to achieve the desired results.
If it’s a very large project, you’ll need to go for a trial -mix. Conduct cube tests of different mix ratios to know the specific results.
Lastly, during the casting, pay attention to the workers, especially when you're not using a ready-made mix, and you're using a mixer on-site.
1. You need someone to monitor the quantities of aggregates, sand, and the water-cement ratio.
Against many beliefs, having too much water will not make your concrete stronger. Too much water will lower the strength of your concrete; you should have an adequate concrete-cement-water ratio.
2. When placing the concrete, you must be mindful of its workability.
The height of pouring must be less than 1 meter to avoid segregation.
During placement, supervise the vibration process.
Concrete must be vibrated to a certain standard. If you use a good concrete mix ratio and it’s not well vibrated, you won’t achieve the required strength. Vibration is crucial to eliminate voids in the concrete, ensuring a solid final product.
After casting, you should emphasize curing.
Many people don't pay attention to curing. Curing is very important. Concrete without curing will not attain the same strength as properly cured concrete.
Big Kay: I know you just completed a concrete project, as you posted on your status. Is there anything you want us to learn from that concrete work regarding attention to detail?
WOli: You be monitoring spirit 😂😂Yes, there’s a lot to learn. I’m familiar with the area in Osun state , so I know there’s no way to get very good sharp sand there.
What I did was use two types of granite: three-quarter down and three-quarter up, then I got stone dust, and I tried as much as possible to obtain drainage sharp sand.
Although the drainage sharp sand isn't as pure as what we normally have in Lagos and Ogun , it’s better than what’s brought from the local farm ground .
I also bought admixture because I don’t compromise on the strength of my concrete. While managing the casting, I engaged the operator regarding the mix ratio we were using, explaining that water should not be excessive. We conducted trial tests, and with experience, I agreed on the percentage of water to use and how to incorporate the admixture.
I brought my electric poker vi****or; for most of them, it was their first time seeing a poker machine. I explained that I would be vibrating my floor to avoid issues. We vibrated the columns, beams, and floor, achieving very solid concrete.
Additionally, many people don’t realize there’s a calculation to determine the materials you need. There's a strategy with supplies. We needed about 50 m³, around 50 tons of granite, but I intentionally bought 60 tons. Don’t buy exact amounts to avoid delays in your work.
So I bought two 30-ton loads which gave me extra 10 tons, ensuring I had enough materials on-site along with stone dust.
Big Kay: Can you share the trick you normally use?
WOli: You always ask for more 🤣
What I typically do is divide my work into three or four sections also my materials and compare my materials on-site as work progresses.
After finishing one part, and nearing halfway through the materials, I know something might be wrong and pay attention to the work on site.
Please don’t ask why I can’t just buy more than enough; some projects pay in stages, and there’s a limit to how far you can go with the available funds to reach the next milestone.
If you don’t understand that aspect, please don’t comment, just learn. After finishing the second section, if I estimate we’ll need about 5 tons of granite, I make arrangements to secure that amount.
For large projects, regularly check the materials on-site against the progress of the work to ensure you can complete the project.
Big Kay: Thank you very much, WOli, the great teacher.
WOli: You’re welcome, Big Kay.
Maybe another day, we can discuss some slang used in concrete work, like 2 for 5, in -Out level, first level, etc.
Big Kay: We can’t wait to have you again, WOli the Great.
WOli: Okay! I inform many people to join the December holiday training on the 11th for just 50k. There’s so much to learn during the training period.
Big Kay: Definitely, many people will participate in the training.
WOli: That’s a good one.
