Heating concrete with electrodes (in winter): technology, connection diagram, calculation

Maintaining the proper temperature for concrete becomes essential when the weather gets cold, especially in the winter. Using heating electrodes is one efficient way to make sure your concrete sets correctly. By inserting electrodes into the concrete and passing an electric current through them, this method helps to maintain the proper temperature for curing by producing heat.

This article will walk you through the fundamentals of using electrodes to heat concrete, including the science involved, how to connect the electrodes, and how to determine how much heat is required. Knowing this procedure will help you handle concrete work more skillfully in cold weather, regardless of whether you’re a professional in construction or a do-it-yourself enthusiast.

We will simplify the essential procedures and factors to make using this approach easier for you. You’ll find comprehensive instructions to help you confidently use this technique to keep your concrete projects on schedule, even in the worst winter conditions. These instructions cover everything from setting up the connection diagram to carrying out the necessary calculations.

Using electrodes to heat concrete while working in cold weather is a useful way to make sure it cures properly. With this technique, heat is produced by introducing electrodes into the concrete and running an electrical current through them. It is possible to ensure that your concrete sets correctly even in freezing conditions by managing the process effectively and being aware of the technology, connection diagrams, and calculations involved.

Why is it needed

You must first comprehend the purpose of the technology before delving into its features.

Every concrete mixture has a tiny amount of liquid in it. Furthermore, when the temperature falls below zero, water quickly freezes and crystallizes, which can cause internal deformation processes in the material. Its strength characteristics and service life are consequently diminished.

The freezing of water during the hardening stage is the next risky factor. Uneven hardening results from the chemical reaction between the components being suspended at low temperatures. You can get rid of these problems and keep the material safe by heating the concrete with electrodes.

Advantages

Three experts are sufficient to complete the concrete heating process. This is regarded as a significant benefit since it removes the need to summon an entire team of employees. The process is also very effective in preserving the structural integrity and encouraging consistent component hardening.

1. No difficulties with self-assembly and high speed of work.
2. Increasing the strength properties of concrete and increasing its service life.

Usually, one electrode is sufficient to perform heating.

Disadvantages

Nevertheless, this method has drawbacks in addition to its benefits.

1. High costs of electrical energy. For normal operation of the electrode, about 50 A is required, as well as the presence of step-down transformers. In addition to these parts, you will have to purchase additional equipment, which is accompanied by financial costs.
2. High cost. The next disadvantage that discourages builders from using electrodes for heating concrete is their high cost. All elements are suitable for one-time use only, so after installation they remain in the screed forever. You can"t take them out of there.

But the material’s increased strength and longer service life more than make up for the aforementioned drawbacks.

Heating modes for concrete electrodes

Selecting heating options for concrete during the winter

1. Dimensions and geometric design features.
2. Concrete grade.
3. Construction operating conditions.

Whatever the approach, it is imperative to keep an eye on the temperature readings and begin work at +5 °C. Over time, raise the temperature by 8 to 15 °C every hour. It is acceptable to use +55–+75 °C. It is essential to take regular temperature readings in order to prevent variations.

The laboratory analysis of compressive strength is taken into consideration when choosing the duration of isothermal holding. The precise details vary depending on the kind of cement, the temperature at which it is heated, and the material’s anticipated strength.

The rate at which concrete can cool is between 5 and 10 °C per hour. The volume and purpose of the structure must be considered here, just as they are during the heating of the concrete stage.

Types of electrolytes for heating concrete in winter

Different kinds of electrodes are used to heat concrete electrically.

These are 20–50 mm wide metal strips. positioned on the solution’s surface and given power from various stages. Ideal for horizontal structures such as floor slab arrangements.

Methods for installing electrodes in a structure

The electrodes are submerged in the poured mixture in intervals of 60–100 cm as part of the heating technology. The structure’s geometrical features and the local weather determine the precise distance.

In order to prevent detrimental effects on the substance, it is crucial

1. The minimum distance between working parts is 200-400 mm.
2. The distance between the electrode and the frame rods is 50-150 mm.
3. Distance to technological seam – from 100 mm.
4. Distance to formwork from the outermost row – from 30 mm.

An ebonite insulating tube can be used to cover the electrodes if the structure of the object being heated makes compliance with these specifications impossible. Once the filling is finished, the area needs to be covered with plastic film, roofing felt, or another heat-insulating material. Concrete heated by electricity will heat less effectively if there is inadequate insulation.

Types of electrodes used

Three different kinds of electrodes are used to heat concrete. Their operating principles and design features are different, and they are made for different environments. As a result, rod models are made using reinforced components that have an 8–12 mm diameter.

They are linked following an initial computation of the best course of action. The final segment is attached up to 3 centimeters away from the formwork. This will enable full heating of the wall or column’s edges.

Plate models work on a slightly different principle. For the purpose of creating a strong electric field and the best temperature indicators possible during heating, they must be fixed in various locations throughout the formwork.

When heating columns, the string variety is more popular.

Electrode connection diagram

Their type and working principle have a direct bearing on the electrode connection diagram. Phase 1 must be connected to the first electrode and phase 2 to the opposite electrode if plates are chosen. We refer to this technique as parallel. Connecting the first and last electrode in a row is what is meant by rod elements.

Regarding step-down transformers, there are situations when using them is not necessary. However, it is preferable to take care of the existence of such a unit in order to prevent the solution from drying out too much.

An effective way to keep ideal curing conditions during the winter is to heat concrete using electrodes. This process ensures that the concrete sets properly even in below-freezing temperatures by creating heat inside the material through the use of electrical current. This method improves the overall strength and durability of the concrete while also hastening the curing process.

This method’s technology is simple: electrodes are inserted into the concrete mixture and an electrical current is then passed through them. By directly generating heat within the concrete, this process effectively combats the winter’s chill. It’s a dependable method that many construction projects use to stay on schedule.

It is imperative to take into account the accurate connection diagram and power requirements computation when preparing to employ this method. An appropriate configuration guarantees effective heating and averts possible problems, like uneven curing or overheating. When used properly, heating concrete with electrodes can be a very efficient way to solve problems that arise during winter construction.

Video on the topic

electrodes . heating concrete . winter. tmo . electrician .

heating concrete

Heating concrete with electrodes

How to heat concrete with ELECTRODES/operating principle of electrodes/winter heating of concrete