The greenhouse method is to build a

The greenhouse method is to build a shed around the concrete structure with thermal insulation materials, and install heat sources such as heat fans and steam pipes in the shed to keep the temperature in the shed above 15℃~20℃. This method is only suitable for a small range of concrete, for large and medium-sized concrete maintenance cost is high, generally not used; Four is electric heating pad method: is to use a special cotton pad, cotton pad added resistance wire, the pad is similar to electric heating blanket covered in the surface of concrete, according to the temperature, into 50V~110V power supply, to maintain the temperature of concrete, promote the rapid solidification of concrete, strengthening; Five is electrothermal pole method: it is to use steel reinforcement or thin iron sheet as the electrode to insert into the concrete or embedded in the concrete in advance, through 50V~100V voltage, direct heating of the concrete, make it reach the frost strength as soon as possible. Due to the large power consumption, mass concrete is less used.