Self-leveling cement winter construction considerations
In the north, the temperature in the north is low, can the cement self-leveling be constructed, and in what range can the temperature be constructed? These have seriously affected the construction of cement self-leveling. When cement self-leveling construction, it is generally necessary to carry out the construction according to the instructions on the site with proper mixing of clean water. When the construction temperature reaches the freezing point, the water required for the self-leveling construction of the cement will freeze, and naturally it is impossible to continue the self-leveling of the cement. If the construction temperature does not reach the freezing point, but is below 0 degrees and 5 degrees? The same can not be constructed! This situation and freezing point are two concepts. The former is impossible to construct, the latter is impossible to construct, because at such temperature, although the water does not freeze, the cement self-leveling cannot fully react with water in the normal time range. Its due performance, so if forced construction will naturally leave many sequelae.
The biggest natural obstacle to cement self-leveling winter construction is the temperature problem. Generally speaking, many people are concerned about the indoor temperature. In fact, it is more important to pay attention to the surface temperature. Then there is a floor with warm ground, high temperature, can you construct cement self-leveling? When the local table temperature is very high, the cement is not recommended for self-leveling. The principle is still a hydration reaction problem. The low temperature is the hydration reaction is too slow, the high temperature is the water volatilization too fast, the self-leveling and water in the cement has not been timely Before the reaction is completed, the water first evaporates, causing insufficient water, which also causes many quality problems. Generally speaking, the self-leveling of cement in winter emphasizes the temperature, so the construction in the outdoor is suspended. In fact, most of the self-leveling of cement is still used indoors, but indoor construction cannot be killed by a stick, not all the ground. The project is impossible to construct, but needs to be more active in creating some conditions for ground construction. Too high or too low temperature is a big obstacle to cement self-leveling.
Into the winter cement self-leveling construction requires surface temperature above 5 °C, room temperature is also 5~35 °C, in addition to adhering to the normal construction process, there are some matters to be paid special attention:
1. The interface agent should be painted more fully. The acrylic emulsion (the main component of the interface agent) will have a longer curing time at low temperature, and it needs to be self-leveling after a long time after painting.
2, self-leveling should be placed 2 days in advance to the site or warehouse above 5 °C, so as not to use too low temperature.
3, construction water should be as much as 10 ° C or more, so that the hydration reaction is faster, strict control of the use of cold water below 5 ° C construction. The construction water was taken out one day before the construction and placed at a room temperature of about 20 °C.
4. The self-leveling process should be adjusted according to the water temperature. The water temperature is lower than 10 °C, the stirring time is extended appropriately, and the self-leveling is allowed to stand in the barrel. The lower the water temperature, the longer the standing time is, generally about 10 °C. The clean water should be allowed to stand for 5 minutes and stirred again for normal construction.
5. When the site is geothermal, in the self-leveling construction, a part should be properly closed or closed so that the surface temperature is not higher than 35 °C.
6. During the construction process, the doors and windows are closed in time to avoid the wind.
7. If the site is central air-conditioning, the air-conditioning exhaust should be avoided to blow the ground straight to make the surface lose water too fast, resulting in ashing.
8. In the winter material transportation, anti-freeze interface agent should be used, but the anti-freeze interface agent can only be used under one freeze-thaw cycle, and the second freezing will break the emulsion.
Generally, the master with rich installation experience can determine whether it is necessary to do self-leveling. In order to cause unnecessary ground loss in the later stage, the self-leveling ground must be done, so that we do not have to worry about paving in the later use. The above materials will show bulging and rupture.