1, thermal insulation method, that is, the use of thermal insulation effect of the cover to maintain the concrete mold temperature and the temperature generated by the heat of hydration of the cement over a period of time does not decrease or slowly decrease.
2, when the outdoor average daily temperature for five consecutive days stable below 5 ° C construction process is called winter construction. Winter temperatures drop, many areas below 0 ° C (i.e., negative temperature), soil, concrete, mortar and other moisture contained in the freezing of building materials are prone to brittle cracks, to the construction of the building has brought many difficulties.
3, in the low temperature for a longer period of time, soil particles finer, recharge water is more abundant areas, the soil during the freezing period, due to the film around the soil particles of water and capillary water, the soil moisture constantly to the freezing line accumulation, the formation of ice, the volume increases, so that the void between the soil particles can not be accommodated and upward bulge, resulting in freezing and expansion, and its expansion force can be as large as 0.5 ~ 1.0 MPa.
Winter construction measures, winter construction generally refers to five consecutive days when the average daily temperature is less than five degrees into the winter construction; the northern part of the Northeast generally have five to six months of winter construction period, roughly in mid-October to mid-April.
According to the "Building Construction Manual" in the meteorological data, Harbin winter construction period for 10.18 - 4.14, Mudanjiang for 10.16 - 4.13, Qiqihar, Jiamusi, etc. and they are similar to the Yichun to be longer; as for the winter shutdown also depends on the specifics of the project, there are generally three months or so, if the indoor project words on the shorter, one or two months.
Expanded Information:
Combined with the characteristics of the winter construction, carefully analyze the region's winter construction accident prone to type, cause, identify and find all kinds of major accidents hidden danger and safety production management in the weak links, the region's major accidents and dangerous sources of real to the heart of the numbers and Focused supervision. Strengthen the supervision and inspection of the hierarchy of the higher level to the lower level, strengthen the supervision and inspection of the implementation of safety responsibilities, and pay close attention to the implementation of the measures and implementation.
According to the climate change, the work of different types of work should be flexibly arranged, and outdoor work should be stopped immediately when encountering severe weather such as gale, rain, snow, etc., and water and snow should be removed from the construction site in a timely manner, so that normal construction can be carried out only after effective anti-freezing and anti-skidding measures have been taken. Supervisory units should be strictly controlled to eliminate the hidden danger of falling accidents.
Baidu Encyclopedia - Winter Construction Measures