Q&A for How to Reinforce Concrete

You need to have plans and details prepared by an engineer for the proper thickness and height of the wall, the type of reinforcement, and the foundation. The wall needs to be formed, reinforced, and scored according to the details and instructions of the plans that were approved by the engineer. After that, there will be drainage and backfill that also needs to be done according to what the engineer comes out with. Honestly, this is a process that I wouldn't recommend for a beginner.

A patio needs to be sloped for rainwater to flow downhill away from the home. It is possible to pour new concrete over the top of an existing concrete slab, but you should drastically rough up to top surface first so that it is like jagged rocks to secure the slab and prevent it from moving around, especially during freezing winters. Thin layers are susceptible to cracking. If your old slab prevents you from pouring at least 2 inches, then you should break up enough existing concrete to allow for that minimal thickness to be poured. No need for gravel for the thin pours: stick to sand and high PSI concrete (4000-5000 PSI). Add lignosulphonate or 0.5% molasses to increase the curing time.

Mix 1 part cement, 3 parts sand, 3 parts gravel, and 2 parts small broken glass. The glass stops the rats from digging into the slab.

A 1 :3:5 ratio of cement - sand - gravel is suggested with 311 of water per 5O kg sack of cement and size of gravel should be small.

Well-graded aggregate, because it has less voids. Interlocking of the particles occurs, which promotes strength.

You will want a 5000 PSI mix. Aggregate (should not be more than 1/5 the thickness of the slab and no more than 3/4 of the thickness of the spacing.

Yes; gravel acts as a coarse aggregate, and it makes the concrete denser. However, sand contributes more to the strength of the cement.

There are lots of reasons that concrete cracks. It could be that the concrete mix wasn't strong enough for the application. Concrete that dries too fast or is poured during cold weather also tends to crack more easily.

The strength of concrete is essentially dependent on the ratio of the cement to water used in the concrete mix. The aggregates you use requires sufficient water to get a workable mix. The better the grading of the aggregates, the less water will be required. To get a concrete strength of +- 40MPa, you need to add twice the amount of cement (by weight) compared to the amount of water. 1.5 x cement will yield a strength +- 20MPa. The more the cement content, the more surface cracks you will get. A superplastisizer reduces the amount of water and cement required leading to less surface cracking.

If you add fiber to the concrete, it is less likely to have any cracks big enough to notice. It doesn't finish smooth (hairy instead), but is stronger.

This depends mainly on what type of application you're using the concrete in. There are some mixtures that prevent corrosion, some that trap air bubbles in the concrete, etc. Check Method 1 to see some of the most common chemical mixtures used to make concrete stronger.

There are many variables such as the weight and length of the gate and the strength of the soil. Each significantly changes the answer, so do your research or ask an expert.

A ratio of one part cement to two parts sand and three parts aggregate with the least of amount of water needed to get it workable should be fine.

You can't make concrete 100% watertight, but you can increase its watertightness by decreasing the amount of water you use in the mixture. However, be advised that using too little water in the mix can make your concrete less durable, so it's all about finding the right level of durability and watertightness for your purposes.

Yes, but this depends on the thickness of the pour you intend to use (i.e., how thick your concrete will be). Pea gravel often contains stones that are a tad large in diameter (say, 1/4 inch). The maximum diameter of any stone in a concrete mix should never be more than 1/3 of your concrete pour. So, for example, if you're using pea gravel in your concrete, your pour will have to be at least 3/4 inch thick.

It depends on the particular application that you're using the concrete for. However, the best way to make strong concrete is to change the water-to-sand ratio or put certain additives in your mixture to make it more durable. See Method 1 above for more information on how to do this.

Liquid dish soap will make your cement stronger by creating tiny air bubbles on the interior that help prevent cracking. It basically operates as an air-entrainment additive. Use three cups of detergent for a 47-pound bag of cement.

The first way to do this is simply by looking at the sand. The sand should be relatively fine and should not have any visible impurities (like shell and shingles). Then, get your hands wet and rub the sand with them. Good clean sand shouldn't stick to your hand. If the sand sticks to your hand and leaves a sort of gray color, that means it contains clay. Finally, you can check for organic impurities by putting some of the sand in a glass of salt water, stirring it, then letting it settle. If the water turns brown, it contains organic impurities.

Probably a type of sand that's conveniently called "concrete sand" (also sometimes called "utility sand" or "manufactured sand"). This is the most commonly used sand for the majority of concrete applications. However, if you care more about how nice your concrete looks, you may be better off using mason sand or white sand, which are finer types of sand and thus give a more polished appearance to your concrete.

Acryl 60 is a great product that increases the adhesion and cohesion properties of concrete.

You can, but note that this isn't the most common technique for strengthening concrete. You can add granular, fiber, or mesh plastic to concrete to make it stronger without adding too much weight to it.

Polypropylene fibers will make concrete more crack-resistant in most circumstances (e.g., if you're making a sidewalk). If you're looking to prevent cracks in a more industrial application, your best bet will be to use steel fibers.