Perfecting technology of winter concreting of cast-in-situ columns

The article deals with an analysis of the existing systems of the heating method of reinforced concrete structures. It is demonstrated that, concreting of rectangular columns, the area of angles is characterized by a lower concrete quality than in other areas, which causes extensive damage in indicated zones. To remove the existing limitations, the formwork design for concreting of cast-in-situ columns is offered in the article. It was established that during the removal of column formwork one can often observe palled angles with reinforcement uncovering. Corners are the most vulnerable parts under impact forces or static loads during the exploitation. Repair and restoration of the exterior view and protective properties of concrete in column corners often require using materials or repair methods, which increase the cost of construction. The reasons of concrete lower quality are in the incompact joints of formwork elements and the chilled temperature of concrete hardening. Furthermore, the reason is in low temperature in columns corners. It is the consequence of the deficiency of existing heating systems ignores the irregularity of heating proper emission of the heat and increased heat loss in the corners of the columns.