Double-leg reinforced concrete columns of one-storey frame buildings for seismic countries

characteristics, a technique of prototypes and results of pilot studies of the bearing ability and a deformationof knots of reinforced concrete double-legcolumns of one-storeyedframe industrial buildings are provided inarticle at action of low-cyclic sign-variable loadings of type of seismic. Knots were tested sign-variable cyclesquantity not less than 30, at coefficient of asymmetry of a cycle, ρs=-1. The size of loading of a cycle was accepted by equal settlement seismic. Valuesof the skilled ultimate loads experienced knots, both single unilateral, and low-cyclic sign-variable by loadings exceeded values of settlement seismic loads of 50-87%. At the sametime, decreasein the bearing ability of the knotstested by low-cyclic sign-variable loading of average and high levels in comparison with the bearing ability of the reference samples tested by single loading reached 20%.Materials with recommendationsabout tests of knots were used when developing a standard series of columns for applicationin seismic countries to 9 points