Methods of heating the concrete during the winter
Lay concrete in place is necessary as soon as possible and without interruption.Good concrete hardening depends on the chemical reaction of cement with water.A major role in this play are heat and water! As a consequence, in the winter time at low temperatures is necessary to insulate the formwork.After the completion of concreting insulated panels and mats and the upper, exposed surface of concrete.In Russia today are designed and put into practice methods of winter concreting.The most effective of these three methods are:
By way of thermos:/ / Beton2006.ru / list / Rastvor-i-beton / Beton-BSG-M.html "> concrete hardens under BGS";coat ";& Ndash;a layer of insulating material (slag, dust, etc. kamyshita.).These materials are very poor conductors of heat.Because of what the concrete mix is \u200b\u200balmost loses heat, which it won in the manufacture of.Hardening cement gives off heat as well.In many cases, the amount of heat is sufficient to cool down during acquired the necessary strength.This strength allows raspalublivat, design, no longer afraid of freezing.In this case, after thawing, the concrete will not collapse.This method is the simplest and most cost-effective.To implement it, no special hardware.However, this method is applicable only when the concreting of massive structures.This is due to the fact that the thin-walled structures very quickly cooled.
If in a timely manner can not be achieved thermos required strength of concrete, then it is recommended to use artificial heating of concrete with steam or electric shock.The essence of electric heating is that the fresh concrete is introduced metallic electrodes through which electric current is passed.Electrical resistance of a freshly prepared concrete, laid in the formwork, increases as the hardening of concrete.The electric current flowing through the concrete, it will cause heating and hardening:the greater the resistance, the higher the voltage.However, the temperature of the concrete should not exceed 60 degrees.In the manufacture of reinforced concrete structures as electrodes can be used fixtures.
The third way is the following paroprogreva.In the mold on the inside cut out specific channels and through the vapor is passed.If possible, can do double casing and enter the steam in the gap between its walls.In some cases, the pairs pass through pipes that are stacked inside. Heat:/ / Beton2006.ru / "> concrete up to 50 & ndash;80 C.Due to high temperatures, which are created when paroprogreve concrete, and under favorable conditions of moisture-curing concrete is considerably accelerated.For example, after two days you can get such strength that reaches the concrete after hardening of the seven daily under normal conditions.However, paroprogrev require large additional costs.This is its biggest drawback.