Wire for heating concrete: a detailed description

Concreting in winter, as a rule, is not performed, since the solution cannot grab at sub-zero temperatures. But there are cases when the construction needs to be completed in the shortest possible time and it is not possible to transfer work to the spring. Then the application of the heating wire can help, the features of which we will consider in this article.

General provisions

Why it is impossible to pour concrete in sub-zero temperatures? It's simple. In its composition is water, which, as you know, crystallizes and expands in the cold.

In such a state, it literally “plows up” the structure of the solution, violating its integrity, and prevents the fixation of the cement stone. After thawing, you get a loose substance, a little like what you expected.

To ensure a positive temperature of the mixture, the concrete is heated by wire.

The process itself is as follows:

• Before pouring the concrete solution, the electrical cable of certain parameters is fixed to the reinforcement and formwork elements and connected to one or two transformers, depending on the size of the structure.

• After concreting, it is supplied with electric current, which heats the cord to +80 degrees.
• Cement with high thermal conductivity, quickly spreads heat throughout the array, thereby creating favorable conditions for maximum strength. After this, any deformation can be carried out only by cutting the reinforced concrete with diamond circles.

The price of such an event is, of course, considerable, but the result is worth it.

Tip: It is also recommended that in the process of heating to lay on top of the design insulation materials. So you will achieve the best results and can save on energy consumption.

Technical details

Необходимый шнур для проведения обогрева монолитных конструкций из бетона и железобетона в зимнее время обладает определёнными параметрами (читайте также статью «Технология прогрева бетона: особенности строительства в зимний период»).

Structure

Warming wire for concrete has a simple structure:

1. A steel conductor consisting of a single wire, capable of conducting electrical current and has a round shape. Its diameter can be from 1.2 mm to 3 mm.
2. Insulation layer, usually made of polyvinyl chloride or polyethylene.

Performance specifications

• It has high resistance to temperature changes. It does not lose its qualities and is able to work properly in the range from -60 degrees Celsius to +50, which in the case of our climate always means.

Tip: laying is not recommended when the frost is below -15⁰C. This is due to the fact that during the bend, frozen insulation can be damaged.

• Polyethylene or PVC coating provides high water-repellent properties, can withstand the effects of a twenty percent salt solution and thirty percent alkali.
• Laying the cable, you probably have to fold and bend it. If you overdo it, the metal wire may break off inside the insulating sheath. To avoid this, the magnitude of the bend radius should not be less than twenty-five millimeters.

• The instruction also assumes that the minimum distance between the wire elements is at least fifteen millimeters. Overheating can lead to a breakdown of the insulation coating, followed by a short circuit. Sufficient indentation will save you from worrying about this.

• During operation, the cable must operate in a repeated or short-term or long-term mode.
• Power connection must be implemented with “cold” ends and remove the soldering points outside the warm-up area.

Tip: soldering is recommended using a braid made of copper wire. This method is most rational for the operation in question.

• The operational period in compliance with all rules of operation is sixteen years or more.

Electrical indicators

1. The resistance of the product in question depends on the thickness of its cross section, decreasing with its increase:

• 1.2 mm - 0.15 Om;
• 1.4 mm - 0.1 Om;
• 2 mm - 0.025 Om;
• 3 mm - 0.005 Om.

1. Voltage supplied AC is allowed up to 380 V.
2. Nutrition in this case is considered the most appropriate about 65 V.
3. The amount of heat produced depends on the availability of reinforcement in the structure:

• Reinforced concrete massif - 30-35 watts per meter.
• Plain concrete without metal inserts - 35-40 watts per meter.

1. The required heating cycle is usually three days.

Conclusion

Бетон на морозе не способен схватиться должным образом. Это происходит из-за кристаллизации находящейся в нём воды. Для того чтобы сделать данный процесс всё же возможным, используется специальный прогревающий кабель, который монтируется внутрь железобетонной конструкции (см.также статью «Марка бетона для фундамента: критерии выбора и основные показатели качества»).

With the characteristics of such a product you have read above.

The video in this article will provide your attention to the study of additional materials that are directly related to the topic under consideration.

Concrete at any time of year, but approach this case correctly.